Merge branch 'perf-core-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip

Pull perf update from Thomas Gleixner:
 "The perf crowd presents:

  Kernel updates:

   - Removal of jprobes

   - Cleanup and consolidatation the handling of kprobes

   - Cleanup and consolidation of hardware breakpoints

   - The usual pile of fixes and updates to PMUs and event descriptors

  Tooling updates:

   - Updates and improvements all over the place. Nothing outstanding,
     just the (good) boring incremental grump work"

* 'perf-core-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip: (103 commits)
  perf trace: Do not require --no-syscalls to suppress strace like output
  perf bpf: Include uapi/linux/bpf.h from the 'perf trace' script's bpf.h
  perf tools: Allow overriding MAX_NR_CPUS at compile time
  perf bpf: Show better message when failing to load an object
  perf list: Unify metric group description format with PMU event description
  perf vendor events arm64: Update ThunderX2 implementation defined pmu core events
  perf cs-etm: Generate branch sample for CS_ETM_TRACE_ON packet
  perf cs-etm: Generate branch sample when receiving a CS_ETM_TRACE_ON packet
  perf cs-etm: Support dummy address value for CS_ETM_TRACE_ON packet
  perf cs-etm: Fix start tracing packet handling
  perf build: Fix installation directory for eBPF
  perf c2c report: Fix crash for empty browser
  perf tests: Fix indexing when invoking subtests
  perf trace: Beautify the AF_INET & AF_INET6 'socket' syscall 'protocol' args
  perf trace beauty: Add beautifiers for 'socket''s 'protocol' arg
  perf trace beauty: Do not print NULL strarray entries
  perf beauty: Add a generator for IPPROTO_ socket's protocol constants
  tools include uapi: Grab a copy of linux/in.h
  perf tests: Fix complex event name parsing
  perf evlist: Fix error out while applying initial delay and LBR
  ...

Documentation/kprobes.txt

@@ -80,6 +80,26 @@ After the instruction is single-stepped, Kprobes executes the
 "post_handler," if any, that is associated with the kprobe.
 Execution then continues with the instruction following the probepoint.
 
+Changing Execution Path
+-----------------------
+
+Since kprobes can probe into a running kernel code, it can change the
+register set, including instruction pointer. This operation requires
+maximum care, such as keeping the stack frame, recovering the execution
+path etc. Since it operates on a running kernel and needs deep knowledge
+of computer architecture and concurrent computing, you can easily shoot
+your foot.
+
+If you change the instruction pointer (and set up other related
+registers) in pre_handler, you must return !0 so that kprobes stops
+single stepping and just returns to the given address.
+This also means post_handler should not be called anymore.
+
+Note that this operation may be harder on some architectures which use
+TOC (Table of Contents) for function call, since you have to setup a new
+TOC for your function in your module, and recover the old one after
+returning from it.
+
 Return Probes
 -------------
 
@@ -262,7 +282,7 @@ is optimized, that modification is ignored.  Thus, if you want to
 tweak the kernel's execution path, you need to suppress optimization,
 using one of the following techniques:
 
-- Specify an empty function for the kprobe's post_handler or break_handler.
+- Specify an empty function for the kprobe's post_handler.
 
 or
 
@@ -474,7 +494,7 @@ error occurs during registration, all probes in the array, up to
 the bad probe, are safely unregistered before the register_*probes
 function returns.
 
-- kps/rps/jps: an array of pointers to ``*probe`` data structures
+- kps/rps: an array of pointers to ``*probe`` data structures
 - num: the number of the array entries.
 
 .. note::
@@ -566,12 +586,11 @@ the same handler) may run concurrently on different CPUs.
 Kprobes does not use mutexes or allocate memory except during
 registration and unregistration.
 
-Probe handlers are run with preemption disabled.  Depending on the
-architecture and optimization state, handlers may also run with
-interrupts disabled (e.g., kretprobe handlers and optimized kprobe
-handlers run without interrupt disabled on x86/x86-64).  In any case,
-your handler should not yield the CPU (e.g., by attempting to acquire
-a semaphore).
+Probe handlers are run with preemption disabled or interrupt disabled,
+which depends on the architecture and optimization state.  (e.g.,
+kretprobe handlers and optimized kprobe handlers run without interrupt
+disabled on x86/x86-64).  In any case, your handler should not yield
+the CPU (e.g., by attempting to acquire a semaphore, or waiting I/O).
 
 Since a return probe is implemented by replacing the return
 address with the trampoline's address, stack backtraces and calls

arch/arc/include/asm/kprobes.h

@@ -45,8 +45,6 @@ struct prev_kprobe {
 
 struct kprobe_ctlblk {
 	unsigned int kprobe_status;
-	struct pt_regs jprobe_saved_regs;
-	char jprobes_stack[MAX_STACK_SIZE];
 	struct prev_kprobe prev_kprobe;
 };
 

arch/arc/kernel/kprobes.c

@@ -225,24 +225,18 @@ int __kprobes arc_kprobe_handler(unsigned long addr, struct pt_regs *regs)
 
 		/* If we have no pre-handler or it returned 0, we continue with
 		 * normal processing. If we have a pre-handler and it returned
-		 * non-zero - which is expected from setjmp_pre_handler for
-		 * jprobe, we return without single stepping and leave that to
-		 * the break-handler which is invoked by a kprobe from
-		 * jprobe_return
+		 * non-zero - which means user handler setup registers to exit
+		 * to another instruction, we must skip the single stepping.
 		 */
 		if (!p->pre_handler || !p->pre_handler(p, regs)) {
 			setup_singlestep(p, regs);
 			kcb->kprobe_status = KPROBE_HIT_SS;
+		} else {
+			reset_current_kprobe();
+			preempt_enable_no_resched();
 		}
 
 		return 1;
-	} else if (kprobe_running()) {
-		p = __this_cpu_read(current_kprobe);
-		if (p->break_handler && p->break_handler(p, regs)) {
-			setup_singlestep(p, regs);
-			kcb->kprobe_status = KPROBE_HIT_SS;
-			return 1;
-		}
 	}
 
 	/* no_kprobe: */
@@ -386,38 +380,6 @@ int __kprobes kprobe_exceptions_notify(struct notifier_block *self,
 	return ret;
 }
 
-int __kprobes setjmp_pre_handler(struct kprobe *p, struct pt_regs *regs)
-{
-	struct jprobe *jp = container_of(p, struct jprobe, kp);
-	struct kprobe_ctlblk *kcb = get_kprobe_ctlblk();
-	unsigned long sp_addr = regs->sp;
-
-	kcb->jprobe_saved_regs = *regs;
-	memcpy(kcb->jprobes_stack, (void *)sp_addr, MIN_STACK_SIZE(sp_addr));
-	regs->ret = (unsigned long)(jp->entry);
-
-	return 1;
-}
-
-void __kprobes jprobe_return(void)
-{
-	__asm__ __volatile__("unimp_s");
-	return;
-}
-
-int __kprobes longjmp_break_handler(struct kprobe *p, struct pt_regs *regs)
-{
-	struct kprobe_ctlblk *kcb = get_kprobe_ctlblk();
-	unsigned long sp_addr;
-
-	*regs = kcb->jprobe_saved_regs;
-	sp_addr = regs->sp;
-	memcpy((void *)sp_addr, kcb->jprobes_stack, MIN_STACK_SIZE(sp_addr));
-	preempt_enable_no_resched();
-
-	return 1;
-}
-
 static void __used kretprobe_trampoline_holder(void)
 {
 	__asm__ __volatile__(".global kretprobe_trampoline\n"
@@ -483,9 +445,7 @@ static int __kprobes trampoline_probe_handler(struct kprobe *p,
 	kretprobe_assert(ri, orig_ret_address, trampoline_address);
 	regs->ret = orig_ret_address;
 
-	reset_current_kprobe();
 	kretprobe_hash_unlock(current, &flags);
-	preempt_enable_no_resched();
 
 	hlist_for_each_entry_safe(ri, tmp, &empty_rp, hlist) {
 		hlist_del(&ri->hlist);

arch/arm/include/asm/hw_breakpoint.h

@@ -111,14 +111,17 @@ static inline void decode_ctrl_reg(u32 reg,
 	asm volatile("mcr p14, 0, %0, " #N "," #M ", " #OP2 : : "r" (VAL));\
 } while (0)
 
+struct perf_event_attr;
 struct notifier_block;
 struct perf_event;
 struct pmu;
 
 extern int arch_bp_generic_fields(struct arch_hw_breakpoint_ctrl ctrl,
 				  int *gen_len, int *gen_type);
-extern int arch_check_bp_in_kernelspace(struct perf_event *bp);
-extern int arch_validate_hwbkpt_settings(struct perf_event *bp);
+extern int arch_check_bp_in_kernelspace(struct arch_hw_breakpoint *hw);
+extern int hw_breakpoint_arch_parse(struct perf_event *bp,
+				    const struct perf_event_attr *attr,
+				    struct arch_hw_breakpoint *hw);
 extern int hw_breakpoint_exceptions_notify(struct notifier_block *unused,
 					   unsigned long val, void *data);
 

arch/arm/include/asm/kprobes.h

@@ -44,8 +44,6 @@ struct prev_kprobe {
 struct kprobe_ctlblk {
 	unsigned int kprobe_status;
 	struct prev_kprobe prev_kprobe;
-	struct pt_regs jprobe_saved_regs;
-	char jprobes_stack[MAX_STACK_SIZE];
 };
 
 void arch_remove_kprobe(struct kprobe *);

arch/arm/include/asm/probes.h

@@ -51,7 +51,6 @@ struct arch_probes_insn {
  * We assume one instruction can consume at most 64 bytes stack, which is
  * 'push {r0-r15}'. Instructions consume more or unknown stack space like
  * 'str r0, [sp, #-80]' and 'str r0, [sp, r1]' should be prohibit to probe.
- * Both kprobe and jprobe use this macro.
  */
 #define MAX_STACK_SIZE			64
 

arch/arm/kernel/hw_breakpoint.c

@@ -456,14 +456,13 @@ static int get_hbp_len(u8 hbp_len)
 /*
  * Check whether bp virtual address is in kernel space.
  */
-int arch_check_bp_in_kernelspace(struct perf_event *bp)
+int arch_check_bp_in_kernelspace(struct arch_hw_breakpoint *hw)
 {
 	unsigned int len;
 	unsigned long va;
-	struct arch_hw_breakpoint *info = counter_arch_bp(bp);
 
-	va = info->address;
-	len = get_hbp_len(info->ctrl.len);
+	va = hw->address;
+	len = get_hbp_len(hw->ctrl.len);
 
 	return (va >= TASK_SIZE) && ((va + len - 1) >= TASK_SIZE);
 }
@@ -518,42 +517,42 @@ int arch_bp_generic_fields(struct arch_hw_breakpoint_ctrl ctrl,
 /*
  * Construct an arch_hw_breakpoint from a perf_event.
  */
-static int arch_build_bp_info(struct perf_event *bp)
+static int arch_build_bp_info(struct perf_event *bp,
+			      const struct perf_event_attr *attr,
+			      struct arch_hw_breakpoint *hw)
 {
-	struct arch_hw_breakpoint *info = counter_arch_bp(bp);
-
 	/* Type */
-	switch (bp->attr.bp_type) {
+	switch (attr->bp_type) {
 	case HW_BREAKPOINT_X:
-		info->ctrl.type = ARM_BREAKPOINT_EXECUTE;
+		hw->ctrl.type = ARM_BREAKPOINT_EXECUTE;
 		break;
 	case HW_BREAKPOINT_R:
-		info->ctrl.type = ARM_BREAKPOINT_LOAD;
+		hw->ctrl.type = ARM_BREAKPOINT_LOAD;
 		break;
 	case HW_BREAKPOINT_W:
-		info->ctrl.type = ARM_BREAKPOINT_STORE;
+		hw->ctrl.type = ARM_BREAKPOINT_STORE;
 		break;
 	case HW_BREAKPOINT_RW:
-		info->ctrl.type = ARM_BREAKPOINT_LOAD | ARM_BREAKPOINT_STORE;
+		hw->ctrl.type = ARM_BREAKPOINT_LOAD | ARM_BREAKPOINT_STORE;
 		break;
 	default:
 		return -EINVAL;
 	}
 
 	/* Len */
-	switch (bp->attr.bp_len) {
+	switch (attr->bp_len) {
 	case HW_BREAKPOINT_LEN_1:
-		info->ctrl.len = ARM_BREAKPOINT_LEN_1;
+		hw->ctrl.len = ARM_BREAKPOINT_LEN_1;
 		break;
 	case HW_BREAKPOINT_LEN_2:
-		info->ctrl.len = ARM_BREAKPOINT_LEN_2;
+		hw->ctrl.len = ARM_BREAKPOINT_LEN_2;
 		break;
 	case HW_BREAKPOINT_LEN_4:
-		info->ctrl.len = ARM_BREAKPOINT_LEN_4;
+		hw->ctrl.len = ARM_BREAKPOINT_LEN_4;
 		break;
 	case HW_BREAKPOINT_LEN_8:
-		info->ctrl.len = ARM_BREAKPOINT_LEN_8;
-		if ((info->ctrl.type != ARM_BREAKPOINT_EXECUTE)
+		hw->ctrl.len = ARM_BREAKPOINT_LEN_8;
+		if ((hw->ctrl.type != ARM_BREAKPOINT_EXECUTE)
 			&& max_watchpoint_len >= 8)
 			break;
 	default:
@@ -566,24 +565,24 @@ static int arch_build_bp_info(struct perf_event *bp)
 	 * by the hardware and must be aligned to the appropriate number of
 	 * bytes.
 	 */
-	if (info->ctrl.type == ARM_BREAKPOINT_EXECUTE &&
-	    info->ctrl.len != ARM_BREAKPOINT_LEN_2 &&
-	    info->ctrl.len != ARM_BREAKPOINT_LEN_4)
+	if (hw->ctrl.type == ARM_BREAKPOINT_EXECUTE &&
+	    hw->ctrl.len != ARM_BREAKPOINT_LEN_2 &&
+	    hw->ctrl.len != ARM_BREAKPOINT_LEN_4)
 		return -EINVAL;
 
 	/* Address */
-	info->address = bp->attr.bp_addr;
+	hw->address = attr->bp_addr;
 
 	/* Privilege */
-	info->ctrl.privilege = ARM_BREAKPOINT_USER;
-	if (arch_check_bp_in_kernelspace(bp))
-		info->ctrl.privilege |= ARM_BREAKPOINT_PRIV;
+	hw->ctrl.privilege = ARM_BREAKPOINT_USER;
+	if (arch_check_bp_in_kernelspace(hw))
+		hw->ctrl.privilege |= ARM_BREAKPOINT_PRIV;
 
 	/* Enabled? */
-	info->ctrl.enabled = !bp->attr.disabled;
+	hw->ctrl.enabled = !attr->disabled;
 
 	/* Mismatch */
-	info->ctrl.mismatch = 0;
+	hw->ctrl.mismatch = 0;
 
 	return 0;
 }
@@ -591,9 +590,10 @@ static int arch_build_bp_info(struct perf_event *bp)
 /*
  * Validate the arch-specific HW Breakpoint register settings.
  */
-int arch_validate_hwbkpt_settings(struct perf_event *bp)
+int hw_breakpoint_arch_parse(struct perf_event *bp,
+			     const struct perf_event_attr *attr,
+			     struct arch_hw_breakpoint *hw)
 {
-	struct arch_hw_breakpoint *info = counter_arch_bp(bp);
 	int ret = 0;
 	u32 offset, alignment_mask = 0x3;
 
@@ -602,14 +602,14 @@ int arch_validate_hwbkpt_settings(struct perf_event *bp)
 		return -ENODEV;
 
 	/* Build the arch_hw_breakpoint. */
-	ret = arch_build_bp_info(bp);
+	ret = arch_build_bp_info(bp, attr, hw);
 	if (ret)
 		goto out;
 
 	/* Check address alignment. */
-	if (info->ctrl.len == ARM_BREAKPOINT_LEN_8)
+	if (hw->ctrl.len == ARM_BREAKPOINT_LEN_8)
 		alignment_mask = 0x7;
-	offset = info->address & alignment_mask;
+	offset = hw->address & alignment_mask;
 	switch (offset) {
 	case 0:
 		/* Aligned */
@@ -617,19 +617,19 @@ int arch_validate_hwbkpt_settings(struct perf_event *bp)
 	case 1:
 	case 2:
 		/* Allow halfword watchpoints and breakpoints. */
-		if (info->ctrl.len == ARM_BREAKPOINT_LEN_2)
+		if (hw->ctrl.len == ARM_BREAKPOINT_LEN_2)
 			break;
 	case 3:
 		/* Allow single byte watchpoint. */
-		if (info->ctrl.len == ARM_BREAKPOINT_LEN_1)
+		if (hw->ctrl.len == ARM_BREAKPOINT_LEN_1)
 			break;
 	default:
 		ret = -EINVAL;
 		goto out;
 	}
 
-	info->address &= ~alignment_mask;
-	info->ctrl.len <<= offset;
+	hw->address &= ~alignment_mask;
+	hw->ctrl.len <<= offset;
 
 	if (is_default_overflow_handler(bp)) {
 		/*
@@ -640,7 +640,7 @@ int arch_validate_hwbkpt_settings(struct perf_event *bp)
 			return -EINVAL;
 
 		/* We don't allow mismatch breakpoints in kernel space. */
-		if (arch_check_bp_in_kernelspace(bp))
+		if (arch_check_bp_in_kernelspace(hw))
 			return -EPERM;
 
 		/*
@@ -655,8 +655,8 @@ int arch_validate_hwbkpt_settings(struct perf_event *bp)
 		 * reports them.
 		 */
 		if (!debug_exception_updates_fsr() &&
-		    (info->ctrl.type == ARM_BREAKPOINT_LOAD ||
-		     info->ctrl.type == ARM_BREAKPOINT_STORE))
+		    (hw->ctrl.type == ARM_BREAKPOINT_LOAD ||
+		     hw->ctrl.type == ARM_BREAKPOINT_STORE))
 			return -EINVAL;
 	}
 

arch/arm/probes/kprobes/core.c

@@ -47,9 +47,6 @@
 			   (unsigned long)(addr) +	\
 			   (size))
 
-/* Used as a marker in ARM_pc to note when we're in a jprobe. */
-#define JPROBE_MAGIC_ADDR		0xffffffff
-
 DEFINE_PER_CPU(struct kprobe *, current_kprobe) = NULL;
 DEFINE_PER_CPU(struct kprobe_ctlblk, kprobe_ctlblk);
 
@@ -289,8 +286,8 @@ void __kprobes kprobe_handler(struct pt_regs *regs)
 				break;
 			case KPROBE_REENTER:
 				/* A nested probe was hit in FIQ, it is a BUG */
-				pr_warn("Unrecoverable kprobe detected at %p.\n",
-					p->addr);
+				pr_warn("Unrecoverable kprobe detected.\n");
+				dump_kprobe(p);
 				/* fall through */
 			default:
 				/* impossible cases */
@@ -303,10 +300,10 @@ void __kprobes kprobe_handler(struct pt_regs *regs)
 
 			/*
 			 * If we have no pre-handler or it returned 0, we
-			 * continue with normal processing.  If we have a
-			 * pre-handler and it returned non-zero, it prepped
-			 * for calling the break_handler below on re-entry,
-			 * so get out doing nothing more here.
+			 * continue with normal processing. If we have a
+			 * pre-handler and it returned non-zero, it will
+			 * modify the execution path and no need to single
+			 * stepping. Let's just reset current kprobe and exit.
 			 */
 			if (!p->pre_handler || !p->pre_handler(p, regs)) {
 				kcb->kprobe_status = KPROBE_HIT_SS;
@@ -315,20 +312,9 @@ void __kprobes kprobe_handler(struct pt_regs *regs)
 					kcb->kprobe_status = KPROBE_HIT_SSDONE;
 					p->post_handler(p, regs, 0);
 				}
-				reset_current_kprobe();
-			}
-		}
-	} else if (cur) {
-		/* We probably hit a jprobe.  Call its break handler. */
-		if (cur->break_handler && cur->break_handler(cur, regs)) {
-			kcb->kprobe_status = KPROBE_HIT_SS;
-			singlestep(cur, regs, kcb);
-			if (cur->post_handler) {
-				kcb->kprobe_status = KPROBE_HIT_SSDONE;
-				cur->post_handler(cur, regs, 0);
 			}
+			reset_current_kprobe();
 		}
-		reset_current_kprobe();
 	} else {
 		/*
 		 * The probe was removed and a race is in progress.
@@ -521,117 +507,6 @@ void __kprobes arch_prepare_kretprobe(struct kretprobe_instance *ri,
 	regs->ARM_lr = (unsigned long)&kretprobe_trampoline;
 }
 
-int __kprobes setjmp_pre_handler(struct kprobe *p, struct pt_regs *regs)
-{
-	struct jprobe *jp = container_of(p, struct jprobe, kp);
-	struct kprobe_ctlblk *kcb = get_kprobe_ctlblk();
-	long sp_addr = regs->ARM_sp;
-	long cpsr;
-
-	kcb->jprobe_saved_regs = *regs;
-	memcpy(kcb->jprobes_stack, (void *)sp_addr, MIN_STACK_SIZE(sp_addr));
-	regs->ARM_pc = (long)jp->entry;
-
-	cpsr = regs->ARM_cpsr | PSR_I_BIT;
-#ifdef CONFIG_THUMB2_KERNEL
-	/* Set correct Thumb state in cpsr */
-	if (regs->ARM_pc & 1)
-		cpsr |= PSR_T_BIT;
-	else
-		cpsr &= ~PSR_T_BIT;
-#endif
-	regs->ARM_cpsr = cpsr;
-
-	preempt_disable();
-	return 1;
-}
-
-void __kprobes jprobe_return(void)
-{
-	struct kprobe_ctlblk *kcb = get_kprobe_ctlblk();
-
-	__asm__ __volatile__ (
-		/*
-		 * Setup an empty pt_regs. Fill SP and PC fields as
-		 * they're needed by longjmp_break_handler.
-		 *
-		 * We allocate some slack between the original SP and start of
-		 * our fabricated regs. To be precise we want to have worst case
-		 * covered which is STMFD with all 16 regs so we allocate 2 *
-		 * sizeof(struct_pt_regs)).
-		 *
-		 * This is to prevent any simulated instruction from writing
-		 * over the regs when they are accessing the stack.
-		 */
-#ifdef CONFIG_THUMB2_KERNEL
-		"sub    r0, %0, %1		\n\t"
-		"mov    sp, r0			\n\t"
-#else
-		"sub    sp, %0, %1		\n\t"
-#endif
-		"ldr    r0, ="__stringify(JPROBE_MAGIC_ADDR)"\n\t"
-		"str    %0, [sp, %2]		\n\t"
-		"str    r0, [sp, %3]		\n\t"
-		"mov    r0, sp			\n\t"
-		"bl     kprobe_handler		\n\t"
-
-		/*
-		 * Return to the context saved by setjmp_pre_handler
-		 * and restored by longjmp_break_handler.
-		 */
-#ifdef CONFIG_THUMB2_KERNEL
-		"ldr	lr, [sp, %2]		\n\t" /* lr = saved sp */
-		"ldrd	r0, r1, [sp, %5]	\n\t" /* r0,r1 = saved lr,pc */
-		"ldr	r2, [sp, %4]		\n\t" /* r2 = saved psr */
-		"stmdb	lr!, {r0, r1, r2}	\n\t" /* push saved lr and */
-						      /* rfe context */
-		"ldmia	sp, {r0 - r12}		\n\t"
-		"mov	sp, lr			\n\t"
-		"ldr	lr, [sp], #4		\n\t"
-		"rfeia	sp!			\n\t"
-#else
-		"ldr	r0, [sp, %4]		\n\t"
-		"msr	cpsr_cxsf, r0		\n\t"
-		"ldmia	sp, {r0 - pc}		\n\t"
-#endif
-		:
-		: "r" (kcb->jprobe_saved_regs.ARM_sp),
-		  "I" (sizeof(struct pt_regs) * 2),
-		  "J" (offsetof(struct pt_regs, ARM_sp)),
-		  "J" (offsetof(struct pt_regs, ARM_pc)),
-		  "J" (offsetof(struct pt_regs, ARM_cpsr)),
-		  "J" (offsetof(struct pt_regs, ARM_lr))
-		: "memory", "cc");
-}
-
-int __kprobes longjmp_break_handler(struct kprobe *p, struct pt_regs *regs)
-{
-	struct kprobe_ctlblk *kcb = get_kprobe_ctlblk();
-	long stack_addr = kcb->jprobe_saved_regs.ARM_sp;
-	long orig_sp = regs->ARM_sp;
-	struct jprobe *jp = container_of(p, struct jprobe, kp);
-
-	if (regs->ARM_pc == JPROBE_MAGIC_ADDR) {
-		if (orig_sp != stack_addr) {
-			struct pt_regs *saved_regs =
-				(struct pt_regs *)kcb->jprobe_saved_regs.ARM_sp;
-			printk("current sp %lx does not match saved sp %lx\n",
-			       orig_sp, stack_addr);
-			printk("Saved registers for jprobe %p\n", jp);
-			show_regs(saved_regs);
-			printk("Current registers\n");
-			show_regs(regs);
-			BUG();
-		}
-		*regs = kcb->jprobe_saved_regs;
-		memcpy((void *)stack_addr, kcb->jprobes_stack,
-		       MIN_STACK_SIZE(stack_addr));
-		preempt_enable_no_resched();
-		return 1;
-	}
-	return 0;
-}
-
 int __kprobes arch_trampoline_kprobe(struct kprobe *p)
 {
 	return 0;

arch/arm/probes/kprobes/test-core.c

@@ -1461,7 +1461,6 @@ static bool check_test_results(void)
 	print_registers(&result_regs);
 
 	if (mem) {
-		pr_err("current_stack=%p\n", current_stack);
 		pr_err("expected_memory:\n");
 		print_memory(expected_memory, mem_size);
 		pr_err("result_memory:\n");

arch/arm64/include/asm/hw_breakpoint.h

@@ -119,13 +119,16 @@ static inline void decode_ctrl_reg(u32 reg,
 
 struct task_struct;
 struct notifier_block;
+struct perf_event_attr;
 struct perf_event;
 struct pmu;
 
 extern int arch_bp_generic_fields(struct arch_hw_breakpoint_ctrl ctrl,
 				  int *gen_len, int *gen_type, int *offset);
-extern int arch_check_bp_in_kernelspace(struct perf_event *bp);
-extern int arch_validate_hwbkpt_settings(struct perf_event *bp);
+extern int arch_check_bp_in_kernelspace(struct arch_hw_breakpoint *hw);
+extern int hw_breakpoint_arch_parse(struct perf_event *bp,
+				    const struct perf_event_attr *attr,
+				    struct arch_hw_breakpoint *hw);
 extern int hw_breakpoint_exceptions_notify(struct notifier_block *unused,
 					   unsigned long val, void *data);
 

arch/arm64/include/asm/kprobes.h

@@ -48,7 +48,6 @@ struct kprobe_ctlblk {
 	unsigned long saved_irqflag;
 	struct prev_kprobe prev_kprobe;
 	struct kprobe_step_ctx ss_ctx;
-	struct pt_regs jprobe_saved_regs;
 };
 
 void arch_remove_kprobe(struct kprobe *);

arch/arm64/kernel/hw_breakpoint.c

@@ -343,14 +343,13 @@ static int get_hbp_len(u8 hbp_len)
 /*
  * Check whether bp virtual address is in kernel space.
  */
-int arch_check_bp_in_kernelspace(struct perf_event *bp)
+int arch_check_bp_in_kernelspace(struct arch_hw_breakpoint *hw)
 {
 	unsigned int len;
 	unsigned long va;
-	struct arch_hw_breakpoint *info = counter_arch_bp(bp);
 
-	va = info->address;
-	len = get_hbp_len(info->ctrl.len);
+	va = hw->address;
+	len = get_hbp_len(hw->ctrl.len);
 
 	return (va >= TASK_SIZE) && ((va + len - 1) >= TASK_SIZE);
 }
@@ -421,53 +420,53 @@ int arch_bp_generic_fields(struct arch_hw_breakpoint_ctrl ctrl,
 /*
  * Construct an arch_hw_breakpoint from a perf_event.
  */
-static int arch_build_bp_info(struct perf_event *bp)
+static int arch_build_bp_info(struct perf_event *bp,
+			      const struct perf_event_attr *attr,
+			      struct arch_hw_breakpoint *hw)
 {
-	struct arch_hw_breakpoint *info = counter_arch_bp(bp);
-
 	/* Type */
-	switch (bp->attr.bp_type) {
+	switch (attr->bp_type) {
 	case HW_BREAKPOINT_X:
-		info->ctrl.type = ARM_BREAKPOINT_EXECUTE;
+		hw->ctrl.type = ARM_BREAKPOINT_EXECUTE;
 		break;
 	case HW_BREAKPOINT_R:
-		info->ctrl.type = ARM_BREAKPOINT_LOAD;
+		hw->ctrl.type = ARM_BREAKPOINT_LOAD;
 		break;
 	case HW_BREAKPOINT_W:
-		info->ctrl.type = ARM_BREAKPOINT_STORE;
+		hw->ctrl.type = ARM_BREAKPOINT_STORE;
 		break;
 	case HW_BREAKPOINT_RW:
-		info->ctrl.type = ARM_BREAKPOINT_LOAD | ARM_BREAKPOINT_STORE;
+		hw->ctrl.type = ARM_BREAKPOINT_LOAD | ARM_BREAKPOINT_STORE;
 		break;
 	default:
 		return -EINVAL;
 	}
 
 	/* Len */
-	switch (bp->attr.bp_len) {
+	switch (attr->bp_len) {
 	case HW_BREAKPOINT_LEN_1:
-		info->ctrl.len = ARM_BREAKPOINT_LEN_1;
+		hw->ctrl.len = ARM_BREAKPOINT_LEN_1;
 		break;
 	case HW_BREAKPOINT_LEN_2:
-		info->ctrl.len = ARM_BREAKPOINT_LEN_2;
+		hw->ctrl.len = ARM_BREAKPOINT_LEN_2;
 		break;
 	case HW_BREAKPOINT_LEN_3:
-		info->ctrl.len = ARM_BREAKPOINT_LEN_3;
+		hw->ctrl.len = ARM_BREAKPOINT_LEN_3;
 		break;
 	case HW_BREAKPOINT_LEN_4:
-		info->ctrl.len = ARM_BREAKPOINT_LEN_4;
+		hw->ctrl.len = ARM_BREAKPOINT_LEN_4;
 		break;
 	case HW_BREAKPOINT_LEN_5:
-		info->ctrl.len = ARM_BREAKPOINT_LEN_5;
+		hw->ctrl.len = ARM_BREAKPOINT_LEN_5;
 		break;
 	case HW_BREAKPOINT_LEN_6:
-		info->ctrl.len = ARM_BREAKPOINT_LEN_6;
+		hw->ctrl.len = ARM_BREAKPOINT_LEN_6;
 		break;
 	case HW_BREAKPOINT_LEN_7:
-		info->ctrl.len = ARM_BREAKPOINT_LEN_7;
+		hw->ctrl.len = ARM_BREAKPOINT_LEN_7;
 		break;
 	case HW_BREAKPOINT_LEN_8:
-		info->ctrl.len = ARM_BREAKPOINT_LEN_8;
+		hw->ctrl.len = ARM_BREAKPOINT_LEN_8;
 		break;
 	default:
 		return -EINVAL;
@@ -478,37 +477,37 @@ static int arch_build_bp_info(struct perf_event *bp)
 	 * AArch32 also requires breakpoints of length 2 for Thumb.
 	 * Watchpoints can be of length 1, 2, 4 or 8 bytes.
 	 */
-	if (info->ctrl.type == ARM_BREAKPOINT_EXECUTE) {
+	if (hw->ctrl.type == ARM_BREAKPOINT_EXECUTE) {
 		if (is_compat_bp(bp)) {
-			if (info->ctrl.len != ARM_BREAKPOINT_LEN_2 &&
-			    info->ctrl.len != ARM_BREAKPOINT_LEN_4)
+			if (hw->ctrl.len != ARM_BREAKPOINT_LEN_2 &&
+			    hw->ctrl.len != ARM_BREAKPOINT_LEN_4)
 				return -EINVAL;
-		} else if (info->ctrl.len != ARM_BREAKPOINT_LEN_4) {
+		} else if (hw->ctrl.len != ARM_BREAKPOINT_LEN_4) {
 			/*
 			 * FIXME: Some tools (I'm looking at you perf) assume
 			 *	  that breakpoints should be sizeof(long). This
 			 *	  is nonsense. For now, we fix up the parameter
 			 *	  but we should probably return -EINVAL instead.
 			 */
-			info->ctrl.len = ARM_BREAKPOINT_LEN_4;
+			hw->ctrl.len = ARM_BREAKPOINT_LEN_4;
 		}
 	}
 
 	/* Address */
-	info->address = bp->attr.bp_addr;
+	hw->address = attr->bp_addr;
 
 	/*
 	 * Privilege
 	 * Note that we disallow combined EL0/EL1 breakpoints because
 	 * that would complicate the stepping code.
 	 */
-	if (arch_check_bp_in_kernelspace(bp))
-		info->ctrl.privilege = AARCH64_BREAKPOINT_EL1;
+	if (arch_check_bp_in_kernelspace(hw))
+		hw->ctrl.privilege = AARCH64_BREAKPOINT_EL1;
 	else
-		info->ctrl.privilege = AARCH64_BREAKPOINT_EL0;
+		hw->ctrl.privilege = AARCH64_BREAKPOINT_EL0;
 
 	/* Enabled? */
-	info->ctrl.enabled = !bp->attr.disabled;
+	hw->ctrl.enabled = !attr->disabled;
 
 	return 0;
 }
@@ -516,14 +515,15 @@ static int arch_build_bp_info(struct perf_event *bp)
 /*
  * Validate the arch-specific HW Breakpoint register settings.
  */
-int arch_validate_hwbkpt_settings(struct perf_event *bp)
+int hw_breakpoint_arch_parse(struct perf_event *bp,
+			     const struct perf_event_attr *attr,
+			     struct arch_hw_breakpoint *hw)
 {
-	struct arch_hw_breakpoint *info = counter_arch_bp(bp);
 	int ret;
 	u64 alignment_mask, offset;
 
 	/* Build the arch_hw_breakpoint. */
-	ret = arch_build_bp_info(bp);
+	ret = arch_build_bp_info(bp, attr, hw);
 	if (ret)
 		return ret;
 
@@ -537,42 +537,42 @@ int arch_validate_hwbkpt_settings(struct perf_event *bp)
 	 * that here.
 	 */
 	if (is_compat_bp(bp)) {
-		if (info->ctrl.len == ARM_BREAKPOINT_LEN_8)
+		if (hw->ctrl.len == ARM_BREAKPOINT_LEN_8)
 			alignment_mask = 0x7;
 		else
 			alignment_mask = 0x3;
-		offset = info->address & alignment_mask;
+		offset = hw->address & alignment_mask;
 		switch (offset) {
 		case 0:
 			/* Aligned */
 			break;
 		case 1:
 			/* Allow single byte watchpoint. */
-			if (info->ctrl.len == ARM_BREAKPOINT_LEN_1)
+			if (hw->ctrl.len == ARM_BREAKPOINT_LEN_1)
 				break;
 		case 2:
 			/* Allow halfword watchpoints and breakpoints. */
-			if (info->ctrl.len == ARM_BREAKPOINT_LEN_2)
+			if (hw->ctrl.len == ARM_BREAKPOINT_LEN_2)
 				break;
 		default:
 			return -EINVAL;
 		}
 	} else {
-		if (info->ctrl.type == ARM_BREAKPOINT_EXECUTE)
+		if (hw->ctrl.type == ARM_BREAKPOINT_EXECUTE)
 			alignment_mask = 0x3;
 		else
 			alignment_mask = 0x7;
-		offset = info->address & alignment_mask;
+		offset = hw->address & alignment_mask;
 	}
 
-	info->address &= ~alignment_mask;
-	info->ctrl.len <<= offset;
+	hw->address &= ~alignment_mask;
+	hw->ctrl.len <<= offset;
 
 	/*
 	 * Disallow per-task kernel breakpoints since these would
 	 * complicate the stepping code.
 	 */
-	if (info->ctrl.privilege == AARCH64_BREAKPOINT_EL1 && bp->hw.target)
+	if (hw->ctrl.privilege == AARCH64_BREAKPOINT_EL1 && bp->hw.target)
 		return -EINVAL;
 
 	return 0;

arch/arm64/kernel/probes/kprobes.c

@@ -275,7 +275,7 @@ static int __kprobes reenter_kprobe(struct kprobe *p,
 		break;
 	case KPROBE_HIT_SS:
 	case KPROBE_REENTER:
-		pr_warn("Unrecoverable kprobe detected at %p.\n", p->addr);
+		pr_warn("Unrecoverable kprobe detected.\n");
 		dump_kprobe(p);
 		BUG();
 		break;
@@ -395,9 +395,9 @@ static void __kprobes kprobe_handler(struct pt_regs *regs)
 			/*
 			 * If we have no pre-handler or it returned 0, we
 			 * continue with normal processing.  If we have a
-			 * pre-handler and it returned non-zero, it prepped
-			 * for calling the break_handler below on re-entry,
-			 * so get out doing nothing more here.
+			 * pre-handler and it returned non-zero, it will
+			 * modify the execution path and no need to single
+			 * stepping. Let's just reset current kprobe and exit.
 			 *
 			 * pre_handler can hit a breakpoint and can step thru
 			 * before return, keep PSTATE D-flag enabled until
@@ -405,16 +405,8 @@ static void __kprobes kprobe_handler(struct pt_regs *regs)
 			 */
 			if (!p->pre_handler || !p->pre_handler(p, regs)) {
 				setup_singlestep(p, regs, kcb, 0);
-				return;
-			}
-		}
-	} else if ((le32_to_cpu(*(kprobe_opcode_t *) addr) ==
-	    BRK64_OPCODE_KPROBES) && cur_kprobe) {
-		/* We probably hit a jprobe.  Call its break handler. */
-		if (cur_kprobe->break_handler  &&
-		     cur_kprobe->break_handler(cur_kprobe, regs)) {
-			setup_singlestep(cur_kprobe, regs, kcb, 0);
-			return;
+			} else
+				reset_current_kprobe();
 		}
 	}
 	/*
@@ -465,74 +457,6 @@ kprobe_breakpoint_handler(struct pt_regs *regs, unsigned int esr)
 	return DBG_HOOK_HANDLED;
 }
 
-int __kprobes setjmp_pre_handler(struct kprobe *p, struct pt_regs *regs)
-{
-	struct jprobe *jp = container_of(p, struct jprobe, kp);
-	struct kprobe_ctlblk *kcb = get_kprobe_ctlblk();
-
-	kcb->jprobe_saved_regs = *regs;
-	/*
-	 * Since we can't be sure where in the stack frame "stacked"
-	 * pass-by-value arguments are stored we just don't try to
-	 * duplicate any of the stack. Do not use jprobes on functions that
-	 * use more than 64 bytes (after padding each to an 8 byte boundary)
-	 * of arguments, or pass individual arguments larger than 16 bytes.
-	 */
-
-	instruction_pointer_set(regs, (unsigned long) jp->entry);
-	preempt_disable();
-	pause_graph_tracing();
-	return 1;
-}
-
-void __kprobes jprobe_return(void)
-{
-	struct kprobe_ctlblk *kcb = get_kprobe_ctlblk();
-
-	/*
-	 * Jprobe handler return by entering break exception,
-	 * encoded same as kprobe, but with following conditions
-	 * -a special PC to identify it from the other kprobes.
-	 * -restore stack addr to original saved pt_regs
-	 */
-	asm volatile("				mov sp, %0	\n"
-		     "jprobe_return_break:	brk %1		\n"
-		     :
-		     : "r" (kcb->jprobe_saved_regs.sp),
-		       "I" (BRK64_ESR_KPROBES)
-		     : "memory");
-
-	unreachable();
-}
-
-int __kprobes longjmp_break_handler(struct kprobe *p, struct pt_regs *regs)
-{
-	struct kprobe_ctlblk *kcb = get_kprobe_ctlblk();
-	long stack_addr = kcb->jprobe_saved_regs.sp;
-	long orig_sp = kernel_stack_pointer(regs);
-	struct jprobe *jp = container_of(p, struct jprobe, kp);
-	extern const char jprobe_return_break[];
-
-	if (instruction_pointer(regs) != (u64) jprobe_return_break)
-		return 0;
-
-	if (orig_sp != stack_addr) {
-		struct pt_regs *saved_regs =
-		    (struct pt_regs *)kcb->jprobe_saved_regs.sp;
-		pr_err("current sp %lx does not match saved sp %lx\n",
-		       orig_sp, stack_addr);
-		pr_err("Saved registers for jprobe %p\n", jp);
-		__show_regs(saved_regs);
-		pr_err("Current registers\n");
-		__show_regs(regs);
-		BUG();
-	}
-	unpause_graph_tracing();
-	*regs = kcb->jprobe_saved_regs;
-	preempt_enable_no_resched();
-	return 1;
-}
-
 bool arch_within_kprobe_blacklist(unsigned long addr)
 {
 	if ((addr >= (unsigned long)__kprobes_text_start &&

arch/ia64/include/asm/kprobes.h

@@ -82,8 +82,6 @@ struct prev_kprobe {
 #define ARCH_PREV_KPROBE_SZ 2
 struct kprobe_ctlblk {
 	unsigned long kprobe_status;
-	struct pt_regs jprobe_saved_regs;
-	unsigned long jprobes_saved_stacked_regs[MAX_PARAM_RSE_SIZE];
 	unsigned long *bsp;
 	unsigned long cfm;
 	atomic_t prev_kprobe_index;

arch/ia64/include/uapi/asm/break.h

@@ -14,7 +14,6 @@
  */
 #define __IA64_BREAK_KDB		0x80100
 #define __IA64_BREAK_KPROBE		0x81000 /* .. 0x81fff */
-#define __IA64_BREAK_JPROBE		0x82000
 
 /*
  * OS-specific break numbers:

arch/ia64/kernel/Makefile

@@ -25,7 +25,7 @@ obj-$(CONFIG_NUMA)		+= numa.o
 obj-$(CONFIG_PERFMON)		+= perfmon_default_smpl.o
 obj-$(CONFIG_IA64_CYCLONE)	+= cyclone.o
 obj-$(CONFIG_IA64_MCA_RECOVERY)	+= mca_recovery.o
-obj-$(CONFIG_KPROBES)		+= kprobes.o jprobes.o
+obj-$(CONFIG_KPROBES)		+= kprobes.o
 obj-$(CONFIG_DYNAMIC_FTRACE)	+= ftrace.o
 obj-$(CONFIG_KEXEC)		+= machine_kexec.o relocate_kernel.o crash.o
 obj-$(CONFIG_CRASH_DUMP)	+= crash_dump.o

arch/ia64/kernel/jprobes.S

-/*
- * Jprobe specific operations
- *
- * This program is free software; you can redistribute it and/or modify
- * it under the terms of the GNU General Public License as published by
- * the Free Software Foundation; either version 2 of the License, or
- * (at your option) any later version.
- *
- * This program is distributed in the hope that it will be useful,
- * but WITHOUT ANY WARRANTY; without even the implied warranty of
- * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
- * GNU General Public License for more details.
- *
- * You should have received a copy of the GNU General Public License
- * along with this program; if not, write to the Free Software
- * Foundation, Inc., 59 Temple Place - Suite 330, Boston, MA 02111-1307, USA.
- *
- * Copyright (C) Intel Corporation, 2005
- *
- * 2005-May     Rusty Lynch <rusty.lynch@intel.com> and Anil S Keshavamurthy
- *              <anil.s.keshavamurthy@intel.com> initial implementation
- *
- * Jprobes (a.k.a. "jump probes" which is built on-top of kprobes) allow a
- * probe to be inserted into the beginning of a function call.  The fundamental
- * difference between a jprobe and a kprobe is the jprobe handler is executed
- * in the same context as the target function, while the kprobe handlers
- * are executed in interrupt context.
- *
- * For jprobes we initially gain control by placing a break point in the
- * first instruction of the targeted function.  When we catch that specific
- * break, we:
- *        * set the return address to our jprobe_inst_return() function
- *        * jump to the jprobe handler function
- *
- * Since we fixed up the return address, the jprobe handler will return to our
- * jprobe_inst_return() function, giving us control again.  At this point we
- * are back in the parents frame marker, so we do yet another call to our
- * jprobe_break() function to fix up the frame marker as it would normally
- * exist in the target function.
- *
- * Our jprobe_return function then transfers control back to kprobes.c by
- * executing a break instruction using one of our reserved numbers.  When we
- * catch that break in kprobes.c, we continue like we do for a normal kprobe
- * by single stepping the emulated instruction, and then returning execution
- * to the correct location.
- */
-#include <asm/asmmacro.h>
-#include <asm/break.h>
-
-	/*
-	 * void jprobe_break(void)
-	 */
-	.section .kprobes.text, "ax"
-ENTRY(jprobe_break)
-	break.m __IA64_BREAK_JPROBE
-END(jprobe_break)
-
-	/*
-	 * void jprobe_inst_return(void)
-	 */
-GLOBAL_ENTRY(jprobe_inst_return)
-	br.call.sptk.many b0=jprobe_break
-END(jprobe_inst_return)
-
-GLOBAL_ENTRY(invalidate_stacked_regs)
-	movl r16=invalidate_restore_cfm
-	;;
-	mov b6=r16
-	;;
-	br.ret.sptk.many b6
-	;;
-invalidate_restore_cfm:
-	mov r16=ar.rsc
-	;;
-	mov ar.rsc=r0
-	;;
-	loadrs
-	;;
-	mov ar.rsc=r16
-	;;
-	br.cond.sptk.many rp
-END(invalidate_stacked_regs)
-
-GLOBAL_ENTRY(flush_register_stack)
-	// flush dirty regs to backing store (must be first in insn group)
-	flushrs
-	;;
-	br.ret.sptk.many rp
-END(flush_register_stack)
-

arch/ia64/kernel/kprobes.c

@@ -35,8 +35,6 @@
 #include <asm/sections.h>
 #include <asm/exception.h>
 
-extern void jprobe_inst_return(void);
-
 DEFINE_PER_CPU(struct kprobe *, current_kprobe) = NULL;
 DEFINE_PER_CPU(struct kprobe_ctlblk, kprobe_ctlblk);
 
@@ -480,12 +478,9 @@ int __kprobes trampoline_probe_handler(struct kprobe *p, struct pt_regs *regs)
 			 */
 			break;
 	}
-
 	kretprobe_assert(ri, orig_ret_address, trampoline_address);
 
-	reset_current_kprobe();
 	kretprobe_hash_unlock(current, &flags);
-	preempt_enable_no_resched();
 
 	hlist_for_each_entry_safe(ri, tmp, &empty_rp, hlist) {
 		hlist_del(&ri->hlist);
@@ -819,14 +814,6 @@ static int __kprobes pre_kprobes_handler(struct die_args *args)
 			prepare_ss(p, regs);
 			kcb->kprobe_status = KPROBE_REENTER;
 			return 1;
-		} else if (args->err == __IA64_BREAK_JPROBE) {
-			/*
-			 * jprobe instrumented function just completed
-			 */
-			p = __this_cpu_read(current_kprobe);
-			if (p->break_handler && p->break_handler(p, regs)) {
-				goto ss_probe;
-			}
 		} else if (!is_ia64_break_inst(regs)) {
 			/* The breakpoint instruction was removed by
 			 * another cpu right after we hit, no further
@@ -861,15 +848,12 @@ static int __kprobes pre_kprobes_handler(struct die_args *args)
 	set_current_kprobe(p, kcb);
 	kcb->kprobe_status = KPROBE_HIT_ACTIVE;
 
-	if (p->pre_handler && p->pre_handler(p, regs))
-		/*
-		 * Our pre-handler is specifically requesting that we just
-		 * do a return.  This is used for both the jprobe pre-handler
-		 * and the kretprobe trampoline
-		 */
+	if (p->pre_handler && p->pre_handler(p, regs)) {
+		reset_current_kprobe();
+		preempt_enable_no_resched();
 		return 1;
+	}
 
-ss_probe:
 #if !defined(CONFIG_PREEMPT)
 	if (p->ainsn.inst_flag == INST_FLAG_BOOSTABLE && !p->post_handler) {
 		/* Boost up -- we can execute copied instructions directly */
@@ -992,7 +976,6 @@ int __kprobes kprobe_exceptions_notify(struct notifier_block *self,
 	case DIE_BREAK:
 		/* err is break number from ia64_bad_break() */
 		if ((args->err >> 12) == (__IA64_BREAK_KPROBE >> 12)
-			|| args->err == __IA64_BREAK_JPROBE
 			|| args->err == 0)
 			if (pre_kprobes_handler(args))
 				ret = NOTIFY_STOP;
@@ -1040,74 +1023,6 @@ unsigned long arch_deref_entry_point(void *entry)
 	return ((struct fnptr *)entry)->ip;
 }
 
-int __kprobes setjmp_pre_handler(struct kprobe *p, struct pt_regs *regs)
-{
-	struct jprobe *jp = container_of(p, struct jprobe, kp);
-	unsigned long addr = arch_deref_entry_point(jp->entry);
-	struct kprobe_ctlblk *kcb = get_kprobe_ctlblk();
-	struct param_bsp_cfm pa;
-	int bytes;
-
-	/*
-	 * Callee owns the argument space and could overwrite it, eg
-	 * tail call optimization. So to be absolutely safe
-	 * we save the argument space before transferring the control
-	 * to instrumented jprobe function which runs in
-	 * the process context
-	 */
-	pa.ip = regs->cr_iip;
-	unw_init_running(ia64_get_bsp_cfm, &pa);
-	bytes = (char *)ia64_rse_skip_regs(pa.bsp, pa.cfm & 0x3f)
-				- (char *)pa.bsp;
-	memcpy( kcb->jprobes_saved_stacked_regs,
-		pa.bsp,
-		bytes );
-	kcb->bsp = pa.bsp;
-	kcb->cfm = pa.cfm;
-
-	/* save architectural state */
-	kcb->jprobe_saved_regs = *regs;
-
-	/* after rfi, execute the jprobe instrumented function */
-	regs->cr_iip = addr & ~0xFULL;
-	ia64_psr(regs)->ri = addr & 0xf;
-	regs->r1 = ((struct fnptr *)(jp->entry))->gp;
-
-	/*
-	 * fix the return address to our jprobe_inst_return() function
-	 * in the jprobes.S file
-	 */
-	regs->b0 = ((struct fnptr *)(jprobe_inst_return))->ip;
-
-	return 1;
-}
-
-/* ia64 does not need this */
-void __kprobes jprobe_return(void)
-{
-}
-
-int __kprobes longjmp_break_handler(struct kprobe *p, struct pt_regs *regs)
-{
-	struct kprobe_ctlblk *kcb = get_kprobe_ctlblk();
-	int bytes;
-
-	/* restoring architectural state */
-	*regs = kcb->jprobe_saved_regs;
-
-	/* restoring the original argument space */
-	flush_register_stack();
-	bytes = (char *)ia64_rse_skip_regs(kcb->bsp, kcb->cfm & 0x3f)
-				- (char *)kcb->bsp;
-	memcpy( kcb->bsp,
-		kcb->jprobes_saved_stacked_regs,
-		bytes );
-	invalidate_stacked_regs();
-
-	preempt_enable_no_resched();
-	return 1;
-}
-
 static struct kprobe trampoline_p = {
 	.pre_handler = trampoline_probe_handler
 };

arch/mips/include/asm/kprobes.h

@@ -68,16 +68,6 @@ struct prev_kprobe {
 	unsigned long saved_epc;
 };
 
-#define MAX_JPROBES_STACK_SIZE 128
-#define MAX_JPROBES_STACK_ADDR \
-	(((unsigned long)current_thread_info()) + THREAD_SIZE - 32 - sizeof(struct pt_regs))
-
-#define MIN_JPROBES_STACK_SIZE(ADDR)					\
-	((((ADDR) + MAX_JPROBES_STACK_SIZE) > MAX_JPROBES_STACK_ADDR)	\
-		? MAX_JPROBES_STACK_ADDR - (ADDR)			\
-		: MAX_JPROBES_STACK_SIZE)
-
-
 #define SKIP_DELAYSLOT 0x0001
 
 /* per-cpu kprobe control block */
@@ -86,12 +76,9 @@ struct kprobe_ctlblk {
 	unsigned long kprobe_old_SR;
 	unsigned long kprobe_saved_SR;
 	unsigned long kprobe_saved_epc;
-	unsigned long jprobe_saved_sp;
-	struct pt_regs jprobe_saved_regs;
 	/* Per-thread fields, used while emulating branches */
 	unsigned long flags;
 	unsigned long target_epc;
-	u8 jprobes_stack[MAX_JPROBES_STACK_SIZE];
 	struct prev_kprobe prev_kprobe;
 };
 

arch/mips/kernel/kprobes.c

@@ -326,19 +326,13 @@ static int __kprobes kprobe_handler(struct pt_regs *regs)
 				preempt_enable_no_resched();
 			}
 			return 1;
-		} else {
-			if (addr->word != breakpoint_insn.word) {
-				/*
-				 * The breakpoint instruction was removed by
-				 * another cpu right after we hit, no further
-				 * handling of this interrupt is appropriate
-				 */
-				ret = 1;
-				goto no_kprobe;
-			}
-			p = __this_cpu_read(current_kprobe);
-			if (p->break_handler && p->break_handler(p, regs))
-				goto ss_probe;
+		} else if (addr->word != breakpoint_insn.word) {
+			/*
+			 * The breakpoint instruction was removed by
+			 * another cpu right after we hit, no further
+			 * handling of this interrupt is appropriate
+			 */
+			ret = 1;
 		}
 		goto no_kprobe;
 	}
@@ -364,10 +358,11 @@ static int __kprobes kprobe_handler(struct pt_regs *regs)
 
 	if (p->pre_handler && p->pre_handler(p, regs)) {
 		/* handler has already set things up, so skip ss setup */
+		reset_current_kprobe();
+		preempt_enable_no_resched();
 		return 1;
 	}
 
-ss_probe:
 	prepare_singlestep(p, regs, kcb);
 	if (kcb->flags & SKIP_DELAYSLOT) {
 		kcb->kprobe_status = KPROBE_HIT_SSDONE;
@@ -468,51 +463,6 @@ int __kprobes kprobe_exceptions_notify(struct notifier_block *self,
 	return ret;
 }
 
-int __kprobes setjmp_pre_handler(struct kprobe *p, struct pt_regs *regs)
-{
-	struct jprobe *jp = container_of(p, struct jprobe, kp);
-	struct kprobe_ctlblk *kcb = get_kprobe_ctlblk();
-
-	kcb->jprobe_saved_regs = *regs;
-	kcb->jprobe_saved_sp = regs->regs[29];
-
-	memcpy(kcb->jprobes_stack, (void *)kcb->jprobe_saved_sp,
-	       MIN_JPROBES_STACK_SIZE(kcb->jprobe_saved_sp));
-
-	regs->cp0_epc = (unsigned long)(jp->entry);
-
-	return 1;
-}
-
-/* Defined in the inline asm below. */
-void jprobe_return_end(void);
-
-void __kprobes jprobe_return(void)
-{
-	/* Assembler quirk necessitates this '0,code' business.	 */
-	asm volatile(
-		"break 0,%0\n\t"
-		".globl jprobe_return_end\n"
-		"jprobe_return_end:\n"
-		: : "n" (BRK_KPROBE_BP) : "memory");
-}
-
-int __kprobes longjmp_break_handler(struct kprobe *p, struct pt_regs *regs)
-{
-	struct kprobe_ctlblk *kcb = get_kprobe_ctlblk();
-
-	if (regs->cp0_epc >= (unsigned long)jprobe_return &&
-	    regs->cp0_epc <= (unsigned long)jprobe_return_end) {
-		*regs = kcb->jprobe_saved_regs;
-		memcpy((void *)kcb->jprobe_saved_sp, kcb->jprobes_stack,
-		       MIN_JPROBES_STACK_SIZE(kcb->jprobe_saved_sp));
-		preempt_enable_no_resched();
-
-		return 1;
-	}
-	return 0;
-}
-
 /*
  * Function return probe trampoline:
  *	- init_kprobes() establishes a probepoint here
@@ -595,9 +545,7 @@ static int __kprobes trampoline_probe_handler(struct kprobe *p,
 	kretprobe_assert(ri, orig_ret_address, trampoline_address);
 	instruction_pointer(regs) = orig_ret_address;
 
-	reset_current_kprobe();
 	kretprobe_hash_unlock(current, &flags);
-	preempt_enable_no_resched();
 
 	hlist_for_each_entry_safe(ri, tmp, &empty_rp, hlist) {
 		hlist_del(&ri->hlist);

arch/powerpc/include/asm/hw_breakpoint.h

@@ -52,6 +52,7 @@ struct arch_hw_breakpoint {
 #include <asm/reg.h>
 #include <asm/debug.h>
 
+struct perf_event_attr;
 struct perf_event;
 struct pmu;
 struct perf_sample_data;
@@ -60,8 +61,10 @@ struct perf_sample_data;
 
 extern int hw_breakpoint_slots(int type);
 extern int arch_bp_generic_fields(int type, int *gen_bp_type);
-extern int arch_check_bp_in_kernelspace(struct perf_event *bp);
-extern int arch_validate_hwbkpt_settings(struct perf_event *bp);
+extern int arch_check_bp_in_kernelspace(struct arch_hw_breakpoint *hw);
+extern int hw_breakpoint_arch_parse(struct perf_event *bp,
+				    const struct perf_event_attr *attr,
+				    struct arch_hw_breakpoint *hw);
 extern int hw_breakpoint_exceptions_notify(struct notifier_block *unused,
 						unsigned long val, void *data);
 int arch_install_hw_breakpoint(struct perf_event *bp);

arch/powerpc/include/asm/kprobes.h

@@ -88,7 +88,6 @@ struct prev_kprobe {
 struct kprobe_ctlblk {
 	unsigned long kprobe_status;
 	unsigned long kprobe_saved_msr;
-	struct pt_regs jprobe_saved_regs;
 	struct prev_kprobe prev_kprobe;
 };
 
@@ -103,17 +102,6 @@ extern int kprobe_exceptions_notify(struct notifier_block *self,
 extern int kprobe_fault_handler(struct pt_regs *regs, int trapnr);
 extern int kprobe_handler(struct pt_regs *regs);
 extern int kprobe_post_handler(struct pt_regs *regs);
-#ifdef CONFIG_KPROBES_ON_FTRACE
-extern int __is_active_jprobe(unsigned long addr);
-extern int skip_singlestep(struct kprobe *p, struct pt_regs *regs,
-			   struct kprobe_ctlblk *kcb);
-#else
-static inline int skip_singlestep(struct kprobe *p, struct pt_regs *regs,
-				  struct kprobe_ctlblk *kcb)
-{
-	return 0;
-}
-#endif
 #else
 static inline int kprobe_handler(struct pt_regs *regs) { return 0; }
 static inline int kprobe_post_handler(struct pt_regs *regs) { return 0; }

arch/powerpc/kernel/hw_breakpoint.c

@@ -119,11 +119,9 @@ void arch_unregister_hw_breakpoint(struct perf_event *bp)
 /*
  * Check for virtual address in kernel space.
  */
-int arch_check_bp_in_kernelspace(struct perf_event *bp)
+int arch_check_bp_in_kernelspace(struct arch_hw_breakpoint *hw)
 {
-	struct arch_hw_breakpoint *info = counter_arch_bp(bp);
-
-	return is_kernel_addr(info->address);
+	return is_kernel_addr(hw->address);
 }
 
 int arch_bp_generic_fields(int type, int *gen_bp_type)
@@ -141,30 +139,31 @@ int arch_bp_generic_fields(int type, int *gen_bp_type)
 /*
  * Validate the arch-specific HW Breakpoint register settings
  */
-int arch_validate_hwbkpt_settings(struct perf_event *bp)
+int hw_breakpoint_arch_parse(struct perf_event *bp,
+			     const struct perf_event_attr *attr,
+			     struct arch_hw_breakpoint *hw)
 {
 	int ret = -EINVAL, length_max;
-	struct arch_hw_breakpoint *info = counter_arch_bp(bp);
 
 	if (!bp)
 		return ret;
 
-	info->type = HW_BRK_TYPE_TRANSLATE;
-	if (bp->attr.bp_type & HW_BREAKPOINT_R)
-		info->type |= HW_BRK_TYPE_READ;
-	if (bp->attr.bp_type & HW_BREAKPOINT_W)
-		info->type |= HW_BRK_TYPE_WRITE;
-	if (info->type == HW_BRK_TYPE_TRANSLATE)
+	hw->type = HW_BRK_TYPE_TRANSLATE;
+	if (attr->bp_type & HW_BREAKPOINT_R)
+		hw->type |= HW_BRK_TYPE_READ;
+	if (attr->bp_type & HW_BREAKPOINT_W)
+		hw->type |= HW_BRK_TYPE_WRITE;
+	if (hw->type == HW_BRK_TYPE_TRANSLATE)
 		/* must set alteast read or write */
 		return ret;
-	if (!(bp->attr.exclude_user))
-		info->type |= HW_BRK_TYPE_USER;
-	if (!(bp->attr.exclude_kernel))
-		info->type |= HW_BRK_TYPE_KERNEL;
-	if (!(bp->attr.exclude_hv))
-		info->type |= HW_BRK_TYPE_HYP;
-	info->address = bp->attr.bp_addr;
-	info->len = bp->attr.bp_len;
+	if (!attr->exclude_user)
+		hw->type |= HW_BRK_TYPE_USER;
+	if (!attr->exclude_kernel)
+		hw->type |= HW_BRK_TYPE_KERNEL;
+	if (!attr->exclude_hv)
+		hw->type |= HW_BRK_TYPE_HYP;
+	hw->address = attr->bp_addr;
+	hw->len = attr->bp_len;
 
 	/*
 	 * Since breakpoint length can be a maximum of HW_BREAKPOINT_LEN(8)
@@ -178,12 +177,12 @@ int arch_validate_hwbkpt_settings(struct perf_event *bp)
 	if (cpu_has_feature(CPU_FTR_DAWR)) {
 		length_max = 512 ; /* 64 doublewords */
 		/* DAWR region can't cross 512 boundary */
-		if ((bp->attr.bp_addr >> 9) !=
-		    ((bp->attr.bp_addr + bp->attr.bp_len - 1) >> 9))
+		if ((attr->bp_addr >> 9) !=
+		    ((attr->bp_addr + attr->bp_len - 1) >> 9))
 			return -EINVAL;
 	}
-	if (info->len >
-	    (length_max - (info->address & HW_BREAKPOINT_ALIGN)))
+	if (hw->len >
+	    (length_max - (hw->address & HW_BREAKPOINT_ALIGN)))
 		return -EINVAL;
 	return 0;
 }

arch/powerpc/kernel/kprobes-ftrace.c

@@ -25,50 +25,6 @@
 #include <linux/preempt.h>
 #include <linux/ftrace.h>
 
-/*
- * This is called from ftrace code after invoking registered handlers to
- * disambiguate regs->nip changes done by jprobes and livepatch. We check if
- * there is an active jprobe at the provided address (mcount location).
- */
-int __is_active_jprobe(unsigned long addr)
-{
-	if (!preemptible()) {
-		struct kprobe *p = raw_cpu_read(current_kprobe);
-		return (p && (unsigned long)p->addr == addr) ? 1 : 0;
-	}
-
-	return 0;
-}
-
-static nokprobe_inline
-int __skip_singlestep(struct kprobe *p, struct pt_regs *regs,
-		      struct kprobe_ctlblk *kcb, unsigned long orig_nip)
-{
-	/*
-	 * Emulate singlestep (and also recover regs->nip)
-	 * as if there is a nop
-	 */
-	regs->nip = (unsigned long)p->addr + MCOUNT_INSN_SIZE;
-	if (unlikely(p->post_handler)) {
-		kcb->kprobe_status = KPROBE_HIT_SSDONE;
-		p->post_handler(p, regs, 0);
-	}
-	__this_cpu_write(current_kprobe, NULL);
-	if (orig_nip)
-		regs->nip = orig_nip;
-	return 1;
-}
-
-int skip_singlestep(struct kprobe *p, struct pt_regs *regs,
-		    struct kprobe_ctlblk *kcb)
-{
-	if (kprobe_ftrace(p))
-		return __skip_singlestep(p, regs, kcb, 0);
-	else
-		return 0;
-}
-NOKPROBE_SYMBOL(skip_singlestep);
-
 /* Ftrace callback handler for kprobes */
 void kprobe_ftrace_handler(unsigned long nip, unsigned long parent_nip,
 			   struct ftrace_ops *ops, struct pt_regs *regs)
@@ -76,18 +32,14 @@ void kprobe_ftrace_handler(unsigned long nip, unsigned long parent_nip,
 	struct kprobe *p;
 	struct kprobe_ctlblk *kcb;
 
-	preempt_disable();
-
 	p = get_kprobe((kprobe_opcode_t *)nip);
 	if (unlikely(!p) || kprobe_disabled(p))
-		goto end;
+		return;
 
 	kcb = get_kprobe_ctlblk();
 	if (kprobe_running()) {
 		kprobes_inc_nmissed_count(p);
 	} else {
-		unsigned long orig_nip = regs->nip;
-
 		/*
 		 * On powerpc, NIP is *before* this instruction for the
 		 * pre handler
@@ -96,19 +48,23 @@ void kprobe_ftrace_handler(unsigned long nip, unsigned long parent_nip,
 
 		__this_cpu_write(current_kprobe, p);
 		kcb->kprobe_status = KPROBE_HIT_ACTIVE;
-		if (!p->pre_handler || !p->pre_handler(p, regs))
-			__skip_singlestep(p, regs, kcb, orig_nip);
-		else {
+		if (!p->pre_handler || !p->pre_handler(p, regs)) {
 			/*
-			 * If pre_handler returns !0, it sets regs->nip and
-			 * resets current kprobe. In this case, we should not
-			 * re-enable preemption.
+			 * Emulate singlestep (and also recover regs->nip)
+			 * as if there is a nop
 			 */
-			return;
+			regs->nip += MCOUNT_INSN_SIZE;
+			if (unlikely(p->post_handler)) {
+				kcb->kprobe_status = KPROBE_HIT_SSDONE;
+				p->post_handler(p, regs, 0);
+			}
 		}
+		/*
+		 * If pre_handler returns !0, it changes regs->nip. We have to
+		 * skip emulating post_handler.
+		 */
+		__this_cpu_write(current_kprobe, NULL);
 	}
-end:
-	preempt_enable_no_resched();
 }
 NOKPROBE_SYMBOL(kprobe_ftrace_handler);
 

arch/powerpc/kernel/kprobes.c

@@ -317,25 +317,17 @@ int kprobe_handler(struct pt_regs *regs)
 			}
 			prepare_singlestep(p, regs);
 			return 1;
-		} else {
-			if (*addr != BREAKPOINT_INSTRUCTION) {
-				/* If trap variant, then it belongs not to us */
-				kprobe_opcode_t cur_insn = *addr;
-				if (is_trap(cur_insn))
-		       			goto no_kprobe;
-				/* The breakpoint instruction was removed by
-				 * another cpu right after we hit, no further
-				 * handling of this interrupt is appropriate
-				 */
-				ret = 1;
+		} else if (*addr != BREAKPOINT_INSTRUCTION) {
+			/* If trap variant, then it belongs not to us */
+			kprobe_opcode_t cur_insn = *addr;
+
+			if (is_trap(cur_insn))
 				goto no_kprobe;
-			}
-			p = __this_cpu_read(current_kprobe);
-			if (p->break_handler && p->break_handler(p, regs)) {
-				if (!skip_singlestep(p, regs, kcb))
-					goto ss_probe;
-				ret = 1;
-			}
+			/* The breakpoint instruction was removed by
+			 * another cpu right after we hit, no further
+			 * handling of this interrupt is appropriate
+			 */
+			ret = 1;
 		}
 		goto no_kprobe;
 	}
@@ -350,7 +342,7 @@ int kprobe_handler(struct pt_regs *regs)
 			 */
 			kprobe_opcode_t cur_insn = *addr;
 			if (is_trap(cur_insn))
-		       		goto no_kprobe;
+				goto no_kprobe;
 			/*
 			 * The breakpoint instruction was removed right
 			 * after we hit it.  Another cpu has removed
@@ -366,11 +358,13 @@ int kprobe_handler(struct pt_regs *regs)
 
 	kcb->kprobe_status = KPROBE_HIT_ACTIVE;
 	set_current_kprobe(p, regs, kcb);
-	if (p->pre_handler && p->pre_handler(p, regs))
-		/* handler has already set things up, so skip ss setup */
+	if (p->pre_handler && p->pre_handler(p, regs)) {
+		/* handler changed execution path, so skip ss setup */
+		reset_current_kprobe();
+		preempt_enable_no_resched();
 		return 1;
+	}
 
-ss_probe:
 	if (p->ainsn.boostable >= 0) {
 		ret = try_to_emulate(p, regs);
 
@@ -611,60 +605,6 @@ unsigned long arch_deref_entry_point(void *entry)
 }
 NOKPROBE_SYMBOL(arch_deref_entry_point);
 
-int setjmp_pre_handler(struct kprobe *p, struct pt_regs *regs)
-{
-	struct jprobe *jp = container_of(p, struct jprobe, kp);
-	struct kprobe_ctlblk *kcb = get_kprobe_ctlblk();
-
-	memcpy(&kcb->jprobe_saved_regs, regs, sizeof(struct pt_regs));
-
-	/* setup return addr to the jprobe handler routine */
-	regs->nip = arch_deref_entry_point(jp->entry);
-#ifdef PPC64_ELF_ABI_v2
-	regs->gpr[12] = (unsigned long)jp->entry;
-#elif defined(PPC64_ELF_ABI_v1)
-	regs->gpr[2] = (unsigned long)(((func_descr_t *)jp->entry)->toc);
-#endif
-
-	/*
-	 * jprobes use jprobe_return() which skips the normal return
-	 * path of the function, and this messes up the accounting of the
-	 * function graph tracer.
-	 *
-	 * Pause function graph tracing while performing the jprobe function.
-	 */
-	pause_graph_tracing();
-
-	return 1;
-}
-NOKPROBE_SYMBOL(setjmp_pre_handler);
-
-void __used jprobe_return(void)
-{
-	asm volatile("jprobe_return_trap:\n"
-		     "trap\n"
-		     ::: "memory");
-}
-NOKPROBE_SYMBOL(jprobe_return);
-
-int longjmp_break_handler(struct kprobe *p, struct pt_regs *regs)
-{
-	struct kprobe_ctlblk *kcb = get_kprobe_ctlblk();
-
-	if (regs->nip != ppc_kallsyms_lookup_name("jprobe_return_trap")) {
-		pr_debug("longjmp_break_handler NIP (0x%lx) does not match jprobe_return_trap (0x%lx)\n",
-				regs->nip, ppc_kallsyms_lookup_name("jprobe_return_trap"));
-		return 0;
-	}
-
-	memcpy(regs, &kcb->jprobe_saved_regs, sizeof(struct pt_regs));
-	/* It's OK to start function graph tracing again */
-	unpause_graph_tracing();
-	preempt_enable_no_resched();
-	return 1;
-}
-NOKPROBE_SYMBOL(longjmp_break_handler);
-
 static struct kprobe trampoline_p = {
 	.addr = (kprobe_opcode_t *) &kretprobe_trampoline,
 	.pre_handler = trampoline_probe_handler

arch/powerpc/kernel/trace/ftrace_64_mprofile.S

@@ -104,39 +104,13 @@ ftrace_regs_call:
 	bl	ftrace_stub
 	nop
 
-	/* Load the possibly modified NIP */
-	ld	r15, _NIP(r1)
-
+	/* Load ctr with the possibly modified NIP */
+	ld	r3, _NIP(r1)
+	mtctr	r3
 #ifdef CONFIG_LIVEPATCH
-	cmpd	r14, r15	/* has NIP been altered? */
+	cmpd	r14, r3		/* has NIP been altered? */
 #endif
 
-#if defined(CONFIG_LIVEPATCH) && defined(CONFIG_KPROBES_ON_FTRACE)
-	/* NIP has not been altered, skip over further checks */
-	beq	1f
-
-	/* Check if there is an active jprobe on us */
-	subi	r3, r14, 4
-	bl	__is_active_jprobe
-	nop
-
-	/*
-	 * If r3 == 1, then this is a kprobe/jprobe.
-	 * else, this is livepatched function.
-	 *
-	 * The conditional branch for livepatch_handler below will use the
-	 * result of this comparison. For kprobe/jprobe, we just need to branch to
-	 * the new NIP, not call livepatch_handler. The branch below is bne, so we
-	 * want CR0[EQ] to be true if this is a kprobe/jprobe. Which means we want
-	 * CR0[EQ] = (r3 == 1).
-	 */
-	cmpdi	r3, 1
-1:
-#endif
-
-	/* Load CTR with the possibly modified NIP */
-	mtctr	r15
-
 	/* Restore gprs */
 	REST_GPR(0,r1)
 	REST_10GPRS(2,r1)
@@ -154,10 +128,7 @@ ftrace_regs_call:
 	addi r1, r1, SWITCH_FRAME_SIZE
 
 #ifdef CONFIG_LIVEPATCH
-        /*
-	 * Based on the cmpd or cmpdi above, if the NIP was altered and we're
-	 * not on a kprobe/jprobe, then handle livepatch.
-	 */
+        /* Based on the cmpd above, if the NIP was altered handle livepatch */
 	bne-	livepatch_handler
 #endif
 

arch/powerpc/perf/core-book3s.c

@@ -1469,7 +1469,7 @@ static int collect_events(struct perf_event *group, int max_count,
 }
 
 /*
- * Add a event to the PMU.
+ * Add an event to the PMU.
  * If all events are not already frozen, then we disable and
  * re-enable the PMU in order to get hw_perf_enable to do the
  * actual work of reconfiguring the PMU.
@@ -1548,7 +1548,7 @@ static int power_pmu_add(struct perf_event *event, int ef_flags)
 }
 
 /*
- * Remove a event from the PMU.
+ * Remove an event from the PMU.
  */
 static void power_pmu_del(struct perf_event *event, int ef_flags)
 {
@@ -1742,7 +1742,7 @@ static int power_pmu_commit_txn(struct pmu *pmu)
 /*
  * Return 1 if we might be able to put event on a limited PMC,
  * or 0 if not.
- * A event can only go on a limited PMC if it counts something
+ * An event can only go on a limited PMC if it counts something
  * that a limited PMC can count, doesn't require interrupts, and
  * doesn't exclude any processor mode.
  */

arch/s390/include/asm/kprobes.h

@@ -68,8 +68,6 @@ struct kprobe_ctlblk {
 	unsigned long kprobe_saved_imask;
 	unsigned long kprobe_saved_ctl[3];
 	struct prev_kprobe prev_kprobe;
-	struct pt_regs jprobe_saved_regs;
-	kprobe_opcode_t jprobes_stack[MAX_STACK_SIZE];
 };
 
 void arch_remove_kprobe(struct kprobe *p);

arch/s390/kernel/kprobes.c

@@ -321,38 +321,20 @@ static int kprobe_handler(struct pt_regs *regs)
 			 * If we have no pre-handler or it returned 0, we
 			 * continue with single stepping. If we have a
 			 * pre-handler and it returned non-zero, it prepped
-			 * for calling the break_handler below on re-entry
-			 * for jprobe processing, so get out doing nothing
-			 * more here.
+			 * for changing execution path, so get out doing
+			 * nothing more here.
 			 */
 			push_kprobe(kcb, p);
 			kcb->kprobe_status = KPROBE_HIT_ACTIVE;
-			if (p->pre_handler && p->pre_handler(p, regs))
+			if (p->pre_handler && p->pre_handler(p, regs)) {
+				pop_kprobe(kcb);
+				preempt_enable_no_resched();
 				return 1;
+			}
 			kcb->kprobe_status = KPROBE_HIT_SS;
 		}
 		enable_singlestep(kcb, regs, (unsigned long) p->ainsn.insn);
 		return 1;
-	} else if (kprobe_running()) {
-		p = __this_cpu_read(current_kprobe);
-		if (p->break_handler && p->break_handler(p, regs)) {
-			/*
-			 * Continuation after the jprobe completed and
-			 * caused the jprobe_return trap. The jprobe
-			 * break_handler "returns" to the original
-			 * function that still has the kprobe breakpoint
-			 * installed. We continue with single stepping.
-			 */
-			kcb->kprobe_status = KPROBE_HIT_SS;
-			enable_singlestep(kcb, regs,
-					  (unsigned long) p->ainsn.insn);
-			return 1;
-		} /* else:
-		   * No kprobe at this address and the current kprobe
-		   * has no break handler (no jprobe!). The kernel just
-		   * exploded, let the standard trap handler pick up the
-		   * pieces.
-		   */
 	} /* else:
 	   * No kprobe at this address and no active kprobe. The trap has
 	   * not been caused by a kprobe breakpoint. The race of breakpoint
@@ -452,9 +434,7 @@ static int trampoline_probe_handler(struct kprobe *p, struct pt_regs *regs)
 
 	regs->psw.addr = orig_ret_address;
 
-	pop_kprobe(get_kprobe_ctlblk());
 	kretprobe_hash_unlock(current, &flags);
-	preempt_enable_no_resched();
 
 	hlist_for_each_entry_safe(ri, tmp, &empty_rp, hlist) {
 		hlist_del(&ri->hlist);
@@ -661,60 +641,6 @@ int kprobe_exceptions_notify(struct notifier_block *self,
 }
 NOKPROBE_SYMBOL(kprobe_exceptions_notify);
 
-int setjmp_pre_handler(struct kprobe *p, struct pt_regs *regs)
-{
-	struct jprobe *jp = container_of(p, struct jprobe, kp);
-	struct kprobe_ctlblk *kcb = get_kprobe_ctlblk();
-	unsigned long stack;
-
-	memcpy(&kcb->jprobe_saved_regs, regs, sizeof(struct pt_regs));
-
-	/* setup return addr to the jprobe handler routine */
-	regs->psw.addr = (unsigned long) jp->entry;
-	regs->psw.mask &= ~(PSW_MASK_IO | PSW_MASK_EXT);
-
-	/* r15 is the stack pointer */
-	stack = (unsigned long) regs->gprs[15];
-
-	memcpy(kcb->jprobes_stack, (void *) stack, MIN_STACK_SIZE(stack));
-
-	/*
-	 * jprobes use jprobe_return() which skips the normal return
-	 * path of the function, and this messes up the accounting of the
-	 * function graph tracer to get messed up.
-	 *
-	 * Pause function graph tracing while performing the jprobe function.
-	 */
-	pause_graph_tracing();
-	return 1;
-}
-NOKPROBE_SYMBOL(setjmp_pre_handler);
-
-void jprobe_return(void)
-{
-	asm volatile(".word 0x0002");
-}
-NOKPROBE_SYMBOL(jprobe_return);
-
-int longjmp_break_handler(struct kprobe *p, struct pt_regs *regs)
-{
-	struct kprobe_ctlblk *kcb = get_kprobe_ctlblk();
-	unsigned long stack;
-
-	/* It's OK to start function graph tracing again */
-	unpause_graph_tracing();
-
-	stack = (unsigned long) kcb->jprobe_saved_regs.gprs[15];
-
-	/* Put the regs back */
-	memcpy(regs, &kcb->jprobe_saved_regs, sizeof(struct pt_regs));
-	/* put the stack back */
-	memcpy((void *) stack, kcb->jprobes_stack, MIN_STACK_SIZE(stack));
-	preempt_enable_no_resched();
-	return 1;
-}
-NOKPROBE_SYMBOL(longjmp_break_handler);
-
 static struct kprobe trampoline = {
 	.addr = (kprobe_opcode_t *) &kretprobe_trampoline,
 	.pre_handler = trampoline_probe_handler

arch/sh/include/asm/hw_breakpoint.h

@@ -10,7 +10,6 @@
 #include <linux/types.h>
 
 struct arch_hw_breakpoint {
-	char		*name; /* Contains name of the symbol to set bkpt */
 	unsigned long	address;
 	u16		len;
 	u16		type;
@@ -41,6 +40,7 @@ struct sh_ubc {
 	struct clk	*clk;	/* optional interface clock / MSTP bit */
 };
 
+struct perf_event_attr;
 struct perf_event;
 struct task_struct;
 struct pmu;
@@ -54,8 +54,10 @@ static inline int hw_breakpoint_slots(int type)
 }
 
 /* arch/sh/kernel/hw_breakpoint.c */
-extern int arch_check_bp_in_kernelspace(struct perf_event *bp);
-extern int arch_validate_hwbkpt_settings(struct perf_event *bp);
+extern int arch_check_bp_in_kernelspace(struct arch_hw_breakpoint *hw);
+extern int hw_breakpoint_arch_parse(struct perf_event *bp,
+				    const struct perf_event_attr *attr,
+				    struct arch_hw_breakpoint *hw);
 extern int hw_breakpoint_exceptions_notify(struct notifier_block *unused,
 					   unsigned long val, void *data);
 

arch/sh/include/asm/kprobes.h

@@ -27,7 +27,6 @@ struct kprobe;
 
 void arch_remove_kprobe(struct kprobe *);
 void kretprobe_trampoline(void);
-void jprobe_return_end(void);
 
 /* Architecture specific copy of original instruction*/
 struct arch_specific_insn {
@@ -43,9 +42,6 @@ struct prev_kprobe {
 /* per-cpu kprobe control block */
 struct kprobe_ctlblk {
 	unsigned long kprobe_status;
-	unsigned long jprobe_saved_r15;
-	struct pt_regs jprobe_saved_regs;
-	kprobe_opcode_t jprobes_stack[MAX_STACK_SIZE];
 	struct prev_kprobe prev_kprobe;
 };
 

arch/sh/kernel/hw_breakpoint.c

@@ -124,14 +124,13 @@ static int get_hbp_len(u16 hbp_len)
 /*
  * Check for virtual address in kernel space.
  */
-int arch_check_bp_in_kernelspace(struct perf_event *bp)
+int arch_check_bp_in_kernelspace(struct arch_hw_breakpoint *hw)
 {
 	unsigned int len;
 	unsigned long va;
-	struct arch_hw_breakpoint *info = counter_arch_bp(bp);
 
-	va = info->address;
-	len = get_hbp_len(info->len);
+	va = hw->address;
+	len = get_hbp_len(hw->len);
 
 	return (va >= TASK_SIZE) && ((va + len - 1) >= TASK_SIZE);
 }
@@ -174,40 +173,40 @@ int arch_bp_generic_fields(int sh_len, int sh_type,
 	return 0;
 }
 
-static int arch_build_bp_info(struct perf_event *bp)
+static int arch_build_bp_info(struct perf_event *bp,
+			      const struct perf_event_attr *attr,
+			      struct arch_hw_breakpoint *hw)
 {
-	struct arch_hw_breakpoint *info = counter_arch_bp(bp);
-
-	info->address = bp->attr.bp_addr;
+	hw->address = attr->bp_addr;
 
 	/* Len */
-	switch (bp->attr.bp_len) {
+	switch (attr->bp_len) {
 	case HW_BREAKPOINT_LEN_1:
-		info->len = SH_BREAKPOINT_LEN_1;
+		hw->len = SH_BREAKPOINT_LEN_1;
 		break;
 	case HW_BREAKPOINT_LEN_2:
-		info->len = SH_BREAKPOINT_LEN_2;
+		hw->len = SH_BREAKPOINT_LEN_2;
 		break;
 	case HW_BREAKPOINT_LEN_4:
-		info->len = SH_BREAKPOINT_LEN_4;
+		hw->len = SH_BREAKPOINT_LEN_4;
 		break;
 	case HW_BREAKPOINT_LEN_8:
-		info->len = SH_BREAKPOINT_LEN_8;
+		hw->len = SH_BREAKPOINT_LEN_8;
 		break;
 	default:
 		return -EINVAL;
 	}
 
 	/* Type */
-	switch (bp->attr.bp_type) {
+	switch (attr->bp_type) {
 	case HW_BREAKPOINT_R:
-		info->type = SH_BREAKPOINT_READ;
+		hw->type = SH_BREAKPOINT_READ;
 		break;
 	case HW_BREAKPOINT_W:
-		info->type = SH_BREAKPOINT_WRITE;
+		hw->type = SH_BREAKPOINT_WRITE;
 		break;
 	case HW_BREAKPOINT_W | HW_BREAKPOINT_R:
-		info->type = SH_BREAKPOINT_RW;
+		hw->type = SH_BREAKPOINT_RW;
 		break;
 	default:
 		return -EINVAL;
@@ -219,19 +218,20 @@ static int arch_build_bp_info(struct perf_event *bp)
 /*
  * Validate the arch-specific HW Breakpoint register settings
  */
-int arch_validate_hwbkpt_settings(struct perf_event *bp)
+int hw_breakpoint_arch_parse(struct perf_event *bp,
+			     const struct perf_event_attr *attr,
+			     struct arch_hw_breakpoint *hw)
 {
-	struct arch_hw_breakpoint *info = counter_arch_bp(bp);
 	unsigned int align;
 	int ret;
 
-	ret = arch_build_bp_info(bp);
+	ret = arch_build_bp_info(bp, attr, hw);
 	if (ret)
 		return ret;
 
 	ret = -EINVAL;
 
-	switch (info->len) {
+	switch (hw->len) {
 	case SH_BREAKPOINT_LEN_1:
 		align = 0;
 		break;
@@ -248,18 +248,11 @@ int arch_validate_hwbkpt_settings(struct perf_event *bp)
 		return ret;
 	}
 
-	/*
-	 * For kernel-addresses, either the address or symbol name can be
-	 * specified.
-	 */
-	if (info->name)
-		info->address = (unsigned long)kallsyms_lookup_name(info->name);
-
 	/*
 	 * Check that the low-order bits of the address are appropriate
 	 * for the alignment implied by len.
 	 */
-	if (info->address & align)
+	if (hw->address & align)
 		return -EINVAL;
 
 	return 0;
@@ -346,7 +339,7 @@ static int __kprobes hw_breakpoint_handler(struct die_args *args)
 		perf_bp_event(bp, args->regs);
 
 		/* Deliver the signal to userspace */
-		if (!arch_check_bp_in_kernelspace(bp)) {
+		if (!arch_check_bp_in_kernelspace(&bp->hw.info)) {
 			force_sig_fault(SIGTRAP, TRAP_HWBKPT,
 					(void __user *)NULL, current);
 		}

arch/sh/kernel/kprobes.c

@@ -248,11 +248,6 @@ static int __kprobes kprobe_handler(struct pt_regs *regs)
 			prepare_singlestep(p, regs);
 			kcb->kprobe_status = KPROBE_REENTER;
 			return 1;
-		} else {
-			p = __this_cpu_read(current_kprobe);
-			if (p->break_handler && p->break_handler(p, regs)) {
-				goto ss_probe;
-			}
 		}
 		goto no_kprobe;
 	}
@@ -277,11 +272,13 @@ static int __kprobes kprobe_handler(struct pt_regs *regs)
 	set_current_kprobe(p, regs, kcb);
 	kcb->kprobe_status = KPROBE_HIT_ACTIVE;
 
-	if (p->pre_handler && p->pre_handler(p, regs))
+	if (p->pre_handler && p->pre_handler(p, regs)) {
 		/* handler has already set things up, so skip ss setup */
+		reset_current_kprobe();
+		preempt_enable_no_resched();
 		return 1;
+	}
 
-ss_probe:
 	prepare_singlestep(p, regs);
 	kcb->kprobe_status = KPROBE_HIT_SS;
 	return 1;
@@ -358,8 +355,6 @@ int __kprobes trampoline_probe_handler(struct kprobe *p, struct pt_regs *regs)
 	regs->pc = orig_ret_address;
 	kretprobe_hash_unlock(current, &flags);
 
-	preempt_enable_no_resched();
-
 	hlist_for_each_entry_safe(ri, tmp, &empty_rp, hlist) {
 		hlist_del(&ri->hlist);
 		kfree(ri);
@@ -508,14 +503,8 @@ int __kprobes kprobe_exceptions_notify(struct notifier_block *self,
 				if (post_kprobe_handler(args->regs))
 					ret = NOTIFY_STOP;
 			} else {
-				if (kprobe_handler(args->regs)) {
+				if (kprobe_handler(args->regs))
 					ret = NOTIFY_STOP;
-				} else {
-					p = __this_cpu_read(current_kprobe);
-					if (p->break_handler &&
-					    p->break_handler(p, args->regs))
-						ret = NOTIFY_STOP;
-				}
 			}
 		}
 	}
@@ -523,57 +512,6 @@ int __kprobes kprobe_exceptions_notify(struct notifier_block *self,
 	return ret;
 }
 
-int __kprobes setjmp_pre_handler(struct kprobe *p, struct pt_regs *regs)
-{
-	struct jprobe *jp = container_of(p, struct jprobe, kp);
-	unsigned long addr;
-	struct kprobe_ctlblk *kcb = get_kprobe_ctlblk();
-
-	kcb->jprobe_saved_regs = *regs;
-	kcb->jprobe_saved_r15 = regs->regs[15];
-	addr = kcb->jprobe_saved_r15;
-
-	/*
-	 * TBD: As Linus pointed out, gcc assumes that the callee
-	 * owns the argument space and could overwrite it, e.g.
-	 * tailcall optimization. So, to be absolutely safe
-	 * we also save and restore enough stack bytes to cover
-	 * the argument area.
-	 */
-	memcpy(kcb->jprobes_stack, (kprobe_opcode_t *) addr,
-	       MIN_STACK_SIZE(addr));
-
-	regs->pc = (unsigned long)(jp->entry);
-
-	return 1;
-}
-
-void __kprobes jprobe_return(void)
-{
-	asm volatile ("trapa #0x3a\n\t" "jprobe_return_end:\n\t" "nop\n\t");
-}
-
-int __kprobes longjmp_break_handler(struct kprobe *p, struct pt_regs *regs)
-{
-	struct kprobe_ctlblk *kcb = get_kprobe_ctlblk();
-	unsigned long stack_addr = kcb->jprobe_saved_r15;
-	u8 *addr = (u8 *)regs->pc;
-
-	if ((addr >= (u8 *)jprobe_return) &&
-	    (addr <= (u8 *)jprobe_return_end)) {
-		*regs = kcb->jprobe_saved_regs;
-
-		memcpy((kprobe_opcode_t *)stack_addr, kcb->jprobes_stack,
-		       MIN_STACK_SIZE(stack_addr));
-
-		kcb->kprobe_status = KPROBE_HIT_SS;
-		preempt_enable_no_resched();
-		return 1;
-	}
-
-	return 0;
-}
-
 static struct kprobe trampoline_p = {
 	.addr = (kprobe_opcode_t *)&kretprobe_trampoline,
 	.pre_handler = trampoline_probe_handler

arch/sparc/include/asm/kprobes.h

@@ -44,7 +44,6 @@ struct kprobe_ctlblk {
 	unsigned long kprobe_status;
 	unsigned long kprobe_orig_tnpc;
 	unsigned long kprobe_orig_tstate_pil;
-	struct pt_regs jprobe_saved_regs;
 	struct prev_kprobe prev_kprobe;
 };
 

arch/sparc/kernel/kprobes.c

@@ -147,18 +147,12 @@ static int __kprobes kprobe_handler(struct pt_regs *regs)
 			kcb->kprobe_status = KPROBE_REENTER;
 			prepare_singlestep(p, regs, kcb);
 			return 1;
-		} else {
-			if (*(u32 *)addr != BREAKPOINT_INSTRUCTION) {
+		} else if (*(u32 *)addr != BREAKPOINT_INSTRUCTION) {
 			/* The breakpoint instruction was removed by
 			 * another cpu right after we hit, no further
 			 * handling of this interrupt is appropriate
 			 */
-				ret = 1;
-				goto no_kprobe;
-			}
-			p = __this_cpu_read(current_kprobe);
-			if (p->break_handler && p->break_handler(p, regs))
-				goto ss_probe;
+			ret = 1;
 		}
 		goto no_kprobe;
 	}
@@ -181,10 +175,12 @@ static int __kprobes kprobe_handler(struct pt_regs *regs)
 
 	set_current_kprobe(p, regs, kcb);
 	kcb->kprobe_status = KPROBE_HIT_ACTIVE;
-	if (p->pre_handler && p->pre_handler(p, regs))
+	if (p->pre_handler && p->pre_handler(p, regs)) {
+		reset_current_kprobe();
+		preempt_enable_no_resched();
 		return 1;
+	}
 
-ss_probe:
 	prepare_singlestep(p, regs, kcb);
 	kcb->kprobe_status = KPROBE_HIT_SS;
 	return 1;
@@ -441,53 +437,6 @@ asmlinkage void __kprobes kprobe_trap(unsigned long trap_level,
 	exception_exit(prev_state);
 }
 
-/* Jprobes support.  */
-int __kprobes setjmp_pre_handler(struct kprobe *p, struct pt_regs *regs)
-{
-	struct jprobe *jp = container_of(p, struct jprobe, kp);
-	struct kprobe_ctlblk *kcb = get_kprobe_ctlblk();
-
-	memcpy(&(kcb->jprobe_saved_regs), regs, sizeof(*regs));
-
-	regs->tpc  = (unsigned long) jp->entry;
-	regs->tnpc = ((unsigned long) jp->entry) + 0x4UL;
-	regs->tstate |= TSTATE_PIL;
-
-	return 1;
-}
-
-void __kprobes jprobe_return(void)
-{
-	struct kprobe_ctlblk *kcb = get_kprobe_ctlblk();
-	register unsigned long orig_fp asm("g1");
-
-	orig_fp = kcb->jprobe_saved_regs.u_regs[UREG_FP];
-	__asm__ __volatile__("\n"
-"1:	cmp		%%sp, %0\n\t"
-	"blu,a,pt	%%xcc, 1b\n\t"
-	" restore\n\t"
-	".globl		jprobe_return_trap_instruction\n"
-"jprobe_return_trap_instruction:\n\t"
-	"ta		0x70"
-	: /* no outputs */
-	: "r" (orig_fp));
-}
-
-extern void jprobe_return_trap_instruction(void);
-
-int __kprobes longjmp_break_handler(struct kprobe *p, struct pt_regs *regs)
-{
-	u32 *addr = (u32 *) regs->tpc;
-	struct kprobe_ctlblk *kcb = get_kprobe_ctlblk();
-
-	if (addr == (u32 *) jprobe_return_trap_instruction) {
-		memcpy(regs, &(kcb->jprobe_saved_regs), sizeof(*regs));
-		preempt_enable_no_resched();
-		return 1;
-	}
-	return 0;
-}
-
 /* The value stored in the return address register is actually 2
  * instructions before where the callee will return to.
  * Sequences usually look something like this
@@ -562,9 +511,7 @@ static int __kprobes trampoline_probe_handler(struct kprobe *p,
 	regs->tpc = orig_ret_address;
 	regs->tnpc = orig_ret_address + 4;
 
-	reset_current_kprobe();
 	kretprobe_hash_unlock(current, &flags);
-	preempt_enable_no_resched();
 
 	hlist_for_each_entry_safe(ri, tmp, &empty_rp, hlist) {
 		hlist_del(&ri->hlist);

arch/x86/events/intel/core.c

@@ -2041,15 +2041,15 @@ static void intel_pmu_disable_event(struct perf_event *event)
 	cpuc->intel_ctrl_host_mask &= ~(1ull << hwc->idx);
 	cpuc->intel_cp_status &= ~(1ull << hwc->idx);
 
+	if (unlikely(event->attr.precise_ip))
+		intel_pmu_pebs_disable(event);
+
 	if (unlikely(hwc->config_base == MSR_ARCH_PERFMON_FIXED_CTR_CTRL)) {
 		intel_pmu_disable_fixed(hwc);
 		return;
 	}
 
 	x86_pmu_disable_event(event);
-
-	if (unlikely(event->attr.precise_ip))
-		intel_pmu_pebs_disable(event);
 }
 
 static void intel_pmu_del_event(struct perf_event *event)
@@ -2068,17 +2068,19 @@ static void intel_pmu_read_event(struct perf_event *event)
 		x86_perf_event_update(event);
 }
 
-static void intel_pmu_enable_fixed(struct hw_perf_event *hwc)
+static void intel_pmu_enable_fixed(struct perf_event *event)
 {
+	struct hw_perf_event *hwc = &event->hw;
 	int idx = hwc->idx - INTEL_PMC_IDX_FIXED;
-	u64 ctrl_val, bits, mask;
+	u64 ctrl_val, mask, bits = 0;
 
 	/*
-	 * Enable IRQ generation (0x8),
+	 * Enable IRQ generation (0x8), if not PEBS,
 	 * and enable ring-3 counting (0x2) and ring-0 counting (0x1)
 	 * if requested:
 	 */
-	bits = 0x8ULL;
+	if (!event->attr.precise_ip)
+		bits |= 0x8;
 	if (hwc->config & ARCH_PERFMON_EVENTSEL_USR)
 		bits |= 0x2;
 	if (hwc->config & ARCH_PERFMON_EVENTSEL_OS)
@@ -2120,14 +2122,14 @@ static void intel_pmu_enable_event(struct perf_event *event)
 	if (unlikely(event_is_checkpointed(event)))
 		cpuc->intel_cp_status |= (1ull << hwc->idx);
 
+	if (unlikely(event->attr.precise_ip))
+		intel_pmu_pebs_enable(event);
+
 	if (unlikely(hwc->config_base == MSR_ARCH_PERFMON_FIXED_CTR_CTRL)) {
-		intel_pmu_enable_fixed(hwc);
+		intel_pmu_enable_fixed(event);
 		return;
 	}
 
-	if (unlikely(event->attr.precise_ip))
-		intel_pmu_pebs_enable(event);
-
 	__x86_pmu_enable_event(hwc, ARCH_PERFMON_EVENTSEL_ENABLE);
 }
 
@@ -2280,7 +2282,10 @@ static int intel_pmu_handle_irq(struct pt_regs *regs)
 	 * counters from the GLOBAL_STATUS mask and we always process PEBS
 	 * events via drain_pebs().
 	 */
-	status &= ~(cpuc->pebs_enabled & PEBS_COUNTER_MASK);
+	if (x86_pmu.flags & PMU_FL_PEBS_ALL)
+		status &= ~cpuc->pebs_enabled;
+	else
+		status &= ~(cpuc->pebs_enabled & PEBS_COUNTER_MASK);
 
 	/*
 	 * PEBS overflow sets bit 62 in the global status register
@@ -4072,7 +4077,6 @@ __init int intel_pmu_init(void)
 		intel_pmu_lbr_init_skl();
 
 		x86_pmu.event_constraints = intel_slm_event_constraints;
-		x86_pmu.pebs_constraints = intel_glp_pebs_event_constraints;
 		x86_pmu.extra_regs = intel_glm_extra_regs;
 		/*
 		 * It's recommended to use CPU_CLK_UNHALTED.CORE_P + NPEBS
@@ -4082,6 +4086,7 @@ __init int intel_pmu_init(void)
 		x86_pmu.pebs_prec_dist = true;
 		x86_pmu.lbr_pt_coexist = true;
 		x86_pmu.flags |= PMU_FL_HAS_RSP_1;
+		x86_pmu.flags |= PMU_FL_PEBS_ALL;
 		x86_pmu.get_event_constraints = glp_get_event_constraints;
 		x86_pmu.cpu_events = glm_events_attrs;
 		/* Goldmont Plus has 4-wide pipeline */

arch/x86/events/intel/ds.c

@@ -713,12 +713,6 @@ struct event_constraint intel_glm_pebs_event_constraints[] = {
 	EVENT_CONSTRAINT_END
 };
 
-struct event_constraint intel_glp_pebs_event_constraints[] = {
-	/* Allow all events as PEBS with no flags */
-	INTEL_ALL_EVENT_CONSTRAINT(0, 0xf),
-	EVENT_CONSTRAINT_END
-};
-
 struct event_constraint intel_nehalem_pebs_event_constraints[] = {
 	INTEL_PLD_CONSTRAINT(0x100b, 0xf),      /* MEM_INST_RETIRED.* */
 	INTEL_FLAGS_EVENT_CONSTRAINT(0x0f, 0xf),    /* MEM_UNCORE_RETIRED.* */
@@ -871,6 +865,13 @@ struct event_constraint *intel_pebs_constraints(struct perf_event *event)
 		}
 	}
 
+	/*
+	 * Extended PEBS support
+	 * Makes the PEBS code search the normal constraints.
+	 */
+	if (x86_pmu.flags & PMU_FL_PEBS_ALL)
+		return NULL;
+
 	return &emptyconstraint;
 }
 
@@ -896,10 +897,16 @@ static inline void pebs_update_threshold(struct cpu_hw_events *cpuc)
 {
 	struct debug_store *ds = cpuc->ds;
 	u64 threshold;
+	int reserved;
+
+	if (x86_pmu.flags & PMU_FL_PEBS_ALL)
+		reserved = x86_pmu.max_pebs_events + x86_pmu.num_counters_fixed;
+	else
+		reserved = x86_pmu.max_pebs_events;
 
 	if (cpuc->n_pebs == cpuc->n_large_pebs) {
 		threshold = ds->pebs_absolute_maximum -
-			x86_pmu.max_pebs_events * x86_pmu.pebs_record_size;
+			reserved * x86_pmu.pebs_record_size;
 	} else {
 		threshold = ds->pebs_buffer_base + x86_pmu.pebs_record_size;
 	}
@@ -963,7 +970,11 @@ void intel_pmu_pebs_enable(struct perf_event *event)
 	 * This must be done in pmu::start(), because PERF_EVENT_IOC_PERIOD.
 	 */
 	if (hwc->flags & PERF_X86_EVENT_AUTO_RELOAD) {
-		ds->pebs_event_reset[hwc->idx] =
+		unsigned int idx = hwc->idx;
+
+		if (idx >= INTEL_PMC_IDX_FIXED)
+			idx = MAX_PEBS_EVENTS + (idx - INTEL_PMC_IDX_FIXED);
+		ds->pebs_event_reset[idx] =
 			(u64)(-hwc->sample_period) & x86_pmu.cntval_mask;
 	} else {
 		ds->pebs_event_reset[hwc->idx] = 0;
@@ -1481,9 +1492,10 @@ static void intel_pmu_drain_pebs_nhm(struct pt_regs *iregs)
 	struct debug_store *ds = cpuc->ds;
 	struct perf_event *event;
 	void *base, *at, *top;
-	short counts[MAX_PEBS_EVENTS] = {};
-	short error[MAX_PEBS_EVENTS] = {};
-	int bit, i;
+	short counts[INTEL_PMC_IDX_FIXED + MAX_FIXED_PEBS_EVENTS] = {};
+	short error[INTEL_PMC_IDX_FIXED + MAX_FIXED_PEBS_EVENTS] = {};
+	int bit, i, size;
+	u64 mask;
 
 	if (!x86_pmu.pebs_active)
 		return;
@@ -1493,6 +1505,13 @@ static void intel_pmu_drain_pebs_nhm(struct pt_regs *iregs)
 
 	ds->pebs_index = ds->pebs_buffer_base;
 
+	mask = (1ULL << x86_pmu.max_pebs_events) - 1;
+	size = x86_pmu.max_pebs_events;
+	if (x86_pmu.flags & PMU_FL_PEBS_ALL) {
+		mask |= ((1ULL << x86_pmu.num_counters_fixed) - 1) << INTEL_PMC_IDX_FIXED;
+		size = INTEL_PMC_IDX_FIXED + x86_pmu.num_counters_fixed;
+	}
+
 	if (unlikely(base >= top)) {
 		/*
 		 * The drain_pebs() could be called twice in a short period
@@ -1502,7 +1521,7 @@ static void intel_pmu_drain_pebs_nhm(struct pt_regs *iregs)
 		 * update the event->count for this case.
 		 */
 		for_each_set_bit(bit, (unsigned long *)&cpuc->pebs_enabled,
-				 x86_pmu.max_pebs_events) {
+				 size) {
 			event = cpuc->events[bit];
 			if (event->hw.flags & PERF_X86_EVENT_AUTO_RELOAD)
 				intel_pmu_save_and_restart_reload(event, 0);
@@ -1515,12 +1534,12 @@ static void intel_pmu_drain_pebs_nhm(struct pt_regs *iregs)
 		u64 pebs_status;
 
 		pebs_status = p->status & cpuc->pebs_enabled;
-		pebs_status &= (1ULL << x86_pmu.max_pebs_events) - 1;
+		pebs_status &= mask;
 
 		/* PEBS v3 has more accurate status bits */
 		if (x86_pmu.intel_cap.pebs_format >= 3) {
 			for_each_set_bit(bit, (unsigned long *)&pebs_status,
-					 x86_pmu.max_pebs_events)
+					 size)
 				counts[bit]++;
 
 			continue;
@@ -1568,7 +1587,7 @@ static void intel_pmu_drain_pebs_nhm(struct pt_regs *iregs)
 		counts[bit]++;
 	}
 
-	for (bit = 0; bit < x86_pmu.max_pebs_events; bit++) {
+	for (bit = 0; bit < size; bit++) {
 		if ((counts[bit] == 0) && (error[bit] == 0))
 			continue;
 

arch/x86/events/intel/lbr.c

@@ -216,6 +216,8 @@ static void intel_pmu_lbr_reset_64(void)
 
 void intel_pmu_lbr_reset(void)
 {
+	struct cpu_hw_events *cpuc = this_cpu_ptr(&cpu_hw_events);
+
 	if (!x86_pmu.lbr_nr)
 		return;
 
@@ -223,6 +225,9 @@ void intel_pmu_lbr_reset(void)
 		intel_pmu_lbr_reset_32();
 	else
 		intel_pmu_lbr_reset_64();
+
+	cpuc->last_task_ctx = NULL;
+	cpuc->last_log_id = 0;
 }
 
 /*
@@ -334,6 +339,7 @@ static inline u64 rdlbr_to(unsigned int idx)
 
 static void __intel_pmu_lbr_restore(struct x86_perf_task_context *task_ctx)
 {
+	struct cpu_hw_events *cpuc = this_cpu_ptr(&cpu_hw_events);
 	int i;
 	unsigned lbr_idx, mask;
 	u64 tos;
@@ -344,9 +350,21 @@ static void __intel_pmu_lbr_restore(struct x86_perf_task_context *task_ctx)
 		return;
 	}
 
-	mask = x86_pmu.lbr_nr - 1;
 	tos = task_ctx->tos;
-	for (i = 0; i < tos; i++) {
+	/*
+	 * Does not restore the LBR registers, if
+	 * - No one else touched them, and
+	 * - Did not enter C6
+	 */
+	if ((task_ctx == cpuc->last_task_ctx) &&
+	    (task_ctx->log_id == cpuc->last_log_id) &&
+	    rdlbr_from(tos)) {
+		task_ctx->lbr_stack_state = LBR_NONE;
+		return;
+	}
+
+	mask = x86_pmu.lbr_nr - 1;
+	for (i = 0; i < task_ctx->valid_lbrs; i++) {
 		lbr_idx = (tos - i) & mask;
 		wrlbr_from(lbr_idx, task_ctx->lbr_from[i]);
 		wrlbr_to  (lbr_idx, task_ctx->lbr_to[i]);
@@ -354,14 +372,24 @@ static void __intel_pmu_lbr_restore(struct x86_perf_task_context *task_ctx)
 		if (x86_pmu.intel_cap.lbr_format == LBR_FORMAT_INFO)
 			wrmsrl(MSR_LBR_INFO_0 + lbr_idx, task_ctx->lbr_info[i]);
 	}
+
+	for (; i < x86_pmu.lbr_nr; i++) {
+		lbr_idx = (tos - i) & mask;
+		wrlbr_from(lbr_idx, 0);
+		wrlbr_to(lbr_idx, 0);
+		if (x86_pmu.intel_cap.lbr_format == LBR_FORMAT_INFO)
+			wrmsrl(MSR_LBR_INFO_0 + lbr_idx, 0);
+	}
+
 	wrmsrl(x86_pmu.lbr_tos, tos);
 	task_ctx->lbr_stack_state = LBR_NONE;
 }
 
 static void __intel_pmu_lbr_save(struct x86_perf_task_context *task_ctx)
 {
+	struct cpu_hw_events *cpuc = this_cpu_ptr(&cpu_hw_events);
 	unsigned lbr_idx, mask;
-	u64 tos;
+	u64 tos, from;
 	int i;
 
 	if (task_ctx->lbr_callstack_users == 0) {
@@ -371,15 +399,22 @@ static void __intel_pmu_lbr_save(struct x86_perf_task_context *task_ctx)
 
 	mask = x86_pmu.lbr_nr - 1;
 	tos = intel_pmu_lbr_tos();
-	for (i = 0; i < tos; i++) {
+	for (i = 0; i < x86_pmu.lbr_nr; i++) {
 		lbr_idx = (tos - i) & mask;
-		task_ctx->lbr_from[i] = rdlbr_from(lbr_idx);
+		from = rdlbr_from(lbr_idx);
+		if (!from)
+			break;
+		task_ctx->lbr_from[i] = from;
 		task_ctx->lbr_to[i]   = rdlbr_to(lbr_idx);
 		if (x86_pmu.intel_cap.lbr_format == LBR_FORMAT_INFO)
 			rdmsrl(MSR_LBR_INFO_0 + lbr_idx, task_ctx->lbr_info[i]);
 	}
+	task_ctx->valid_lbrs = i;
 	task_ctx->tos = tos;
 	task_ctx->lbr_stack_state = LBR_VALID;
+
+	cpuc->last_task_ctx = task_ctx;
+	cpuc->last_log_id = ++task_ctx->log_id;
 }
 
 void intel_pmu_lbr_sched_task(struct perf_event_context *ctx, bool sched_in)
@@ -531,7 +566,7 @@ static void intel_pmu_lbr_read_32(struct cpu_hw_events *cpuc)
  */
 static void intel_pmu_lbr_read_64(struct cpu_hw_events *cpuc)
 {
-	bool need_info = false;
+	bool need_info = false, call_stack = false;
 	unsigned long mask = x86_pmu.lbr_nr - 1;
 	int lbr_format = x86_pmu.intel_cap.lbr_format;
 	u64 tos = intel_pmu_lbr_tos();
@@ -542,7 +577,7 @@ static void intel_pmu_lbr_read_64(struct cpu_hw_events *cpuc)
 	if (cpuc->lbr_sel) {
 		need_info = !(cpuc->lbr_sel->config & LBR_NO_INFO);
 		if (cpuc->lbr_sel->config & LBR_CALL_STACK)
-			num = tos;
+			call_stack = true;
 	}
 
 	for (i = 0; i < num; i++) {
@@ -555,6 +590,13 @@ static void intel_pmu_lbr_read_64(struct cpu_hw_events *cpuc)
 		from = rdlbr_from(lbr_idx);
 		to   = rdlbr_to(lbr_idx);
 
+		/*
+		 * Read LBR call stack entries
+		 * until invalid entry (0s) is detected.
+		 */
+		if (call_stack && !from)
+			break;
+
 		if (lbr_format == LBR_FORMAT_INFO && need_info) {
 			u64 info;
 

arch/x86/events/perf_event.h

@@ -163,6 +163,7 @@ struct intel_excl_cntrs {
 	unsigned	core_id;	/* per-core: core id */
 };
 
+struct x86_perf_task_context;
 #define MAX_LBR_ENTRIES		32
 
 enum {
@@ -214,6 +215,8 @@ struct cpu_hw_events {
 	struct perf_branch_entry	lbr_entries[MAX_LBR_ENTRIES];
 	struct er_account		*lbr_sel;
 	u64				br_sel;
+	struct x86_perf_task_context	*last_task_ctx;
+	int				last_log_id;
 
 	/*
 	 * Intel host/guest exclude bits
@@ -648,8 +651,10 @@ struct x86_perf_task_context {
 	u64 lbr_to[MAX_LBR_ENTRIES];
 	u64 lbr_info[MAX_LBR_ENTRIES];
 	int tos;
+	int valid_lbrs;
 	int lbr_callstack_users;
 	int lbr_stack_state;
+	int log_id;
 };
 
 #define x86_add_quirk(func_)						\
@@ -668,6 +673,7 @@ do {									\
 #define PMU_FL_HAS_RSP_1	0x2 /* has 2 equivalent offcore_rsp regs   */
 #define PMU_FL_EXCL_CNTRS	0x4 /* has exclusive counter requirements  */
 #define PMU_FL_EXCL_ENABLED	0x8 /* exclusive counter active */
+#define PMU_FL_PEBS_ALL		0x10 /* all events are valid PEBS events */
 
 #define EVENT_VAR(_id)  event_attr_##_id
 #define EVENT_PTR(_id) &event_attr_##_id.attr.attr

arch/x86/include/asm/hw_breakpoint.h

@@ -49,11 +49,14 @@ static inline int hw_breakpoint_slots(int type)
 	return HBP_NUM;
 }
 
+struct perf_event_attr;
 struct perf_event;
 struct pmu;
 
-extern int arch_check_bp_in_kernelspace(struct perf_event *bp);
-extern int arch_validate_hwbkpt_settings(struct perf_event *bp);
+extern int arch_check_bp_in_kernelspace(struct arch_hw_breakpoint *hw);
+extern int hw_breakpoint_arch_parse(struct perf_event *bp,
+				    const struct perf_event_attr *attr,
+				    struct arch_hw_breakpoint *hw);
 extern int hw_breakpoint_exceptions_notify(struct notifier_block *unused,
 					   unsigned long val, void *data);
 

arch/x86/include/asm/intel_ds.h

@@ -8,6 +8,7 @@
 
 /* The maximal number of PEBS events: */
 #define MAX_PEBS_EVENTS		8
+#define MAX_FIXED_PEBS_EVENTS	3
 
 /*
  * A debug store configuration.
@@ -23,7 +24,7 @@ struct debug_store {
 	u64	pebs_index;
 	u64	pebs_absolute_maximum;
 	u64	pebs_interrupt_threshold;
-	u64	pebs_event_reset[MAX_PEBS_EVENTS];
+	u64	pebs_event_reset[MAX_PEBS_EVENTS + MAX_FIXED_PEBS_EVENTS];
 } __aligned(PAGE_SIZE);
 
 DECLARE_PER_CPU_PAGE_ALIGNED(struct debug_store, cpu_debug_store);

arch/x86/include/asm/kprobes.h

@@ -78,7 +78,7 @@ struct arch_specific_insn {
 	 * boostable = true: This instruction has been boosted: we have
 	 * added a relative jump after the instruction copy in insn,
 	 * so no single-step and fixup are needed (unless there's
-	 * a post_handler or break_handler).
+	 * a post_handler).
 	 */
 	bool boostable;
 	bool if_modifier;
@@ -111,9 +111,6 @@ struct kprobe_ctlblk {
 	unsigned long kprobe_status;
 	unsigned long kprobe_old_flags;
 	unsigned long kprobe_saved_flags;
-	unsigned long *jprobe_saved_sp;
-	struct pt_regs jprobe_saved_regs;
-	kprobe_opcode_t jprobes_stack[MAX_STACK_SIZE];
 	struct prev_kprobe prev_kprobe;
 };
 

arch/x86/kernel/hw_breakpoint.c

@@ -169,28 +169,29 @@ void arch_uninstall_hw_breakpoint(struct perf_event *bp)
 		set_dr_addr_mask(0, i);
 }
 
-/*
- * Check for virtual address in kernel space.
- */
-int arch_check_bp_in_kernelspace(struct perf_event *bp)
+static int arch_bp_generic_len(int x86_len)
 {
-	unsigned int len;
-	unsigned long va;
-	struct arch_hw_breakpoint *info = counter_arch_bp(bp);
-
-	va = info->address;
-	len = bp->attr.bp_len;
-
-	/*
-	 * We don't need to worry about va + len - 1 overflowing:
-	 * we already require that va is aligned to a multiple of len.
-	 */
-	return (va >= TASK_SIZE_MAX) || ((va + len - 1) >= TASK_SIZE_MAX);
+	switch (x86_len) {
+	case X86_BREAKPOINT_LEN_1:
+		return HW_BREAKPOINT_LEN_1;
+	case X86_BREAKPOINT_LEN_2:
+		return HW_BREAKPOINT_LEN_2;
+	case X86_BREAKPOINT_LEN_4:
+		return HW_BREAKPOINT_LEN_4;
+#ifdef CONFIG_X86_64
+	case X86_BREAKPOINT_LEN_8:
+		return HW_BREAKPOINT_LEN_8;
+#endif
+	default:
+		return -EINVAL;
+	}
 }
 
 int arch_bp_generic_fields(int x86_len, int x86_type,
 			   int *gen_len, int *gen_type)
 {
+	int len;
+
 	/* Type */
 	switch (x86_type) {
 	case X86_BREAKPOINT_EXECUTE:
@@ -211,42 +212,47 @@ int arch_bp_generic_fields(int x86_len, int x86_type,
 	}
 
 	/* Len */
-	switch (x86_len) {
-	case X86_BREAKPOINT_LEN_1:
-		*gen_len = HW_BREAKPOINT_LEN_1;
-		break;
-	case X86_BREAKPOINT_LEN_2:
-		*gen_len = HW_BREAKPOINT_LEN_2;
-		break;
-	case X86_BREAKPOINT_LEN_4:
-		*gen_len = HW_BREAKPOINT_LEN_4;
-		break;
-#ifdef CONFIG_X86_64
-	case X86_BREAKPOINT_LEN_8:
-		*gen_len = HW_BREAKPOINT_LEN_8;
-		break;
-#endif
-	default:
+	len = arch_bp_generic_len(x86_len);
+	if (len < 0)
 		return -EINVAL;
-	}
+	*gen_len = len;
 
 	return 0;
 }
 
-
-static int arch_build_bp_info(struct perf_event *bp)
+/*
+ * Check for virtual address in kernel space.
+ */
+int arch_check_bp_in_kernelspace(struct arch_hw_breakpoint *hw)
 {
-	struct arch_hw_breakpoint *info = counter_arch_bp(bp);
+	unsigned long va;
+	int len;
 
-	info->address = bp->attr.bp_addr;
+	va = hw->address;
+	len = arch_bp_generic_len(hw->len);
+	WARN_ON_ONCE(len < 0);
+
+	/*
+	 * We don't need to worry about va + len - 1 overflowing:
+	 * we already require that va is aligned to a multiple of len.
+	 */
+	return (va >= TASK_SIZE_MAX) || ((va + len - 1) >= TASK_SIZE_MAX);
+}
+
+static int arch_build_bp_info(struct perf_event *bp,
+			      const struct perf_event_attr *attr,
+			      struct arch_hw_breakpoint *hw)
+{
+	hw->address = attr->bp_addr;
+	hw->mask = 0;
 
 	/* Type */
-	switch (bp->attr.bp_type) {
+	switch (attr->bp_type) {
 	case HW_BREAKPOINT_W:
-		info->type = X86_BREAKPOINT_WRITE;
+		hw->type = X86_BREAKPOINT_WRITE;
 		break;
 	case HW_BREAKPOINT_W | HW_BREAKPOINT_R:
-		info->type = X86_BREAKPOINT_RW;
+		hw->type = X86_BREAKPOINT_RW;
 		break;
 	case HW_BREAKPOINT_X:
 		/*
@@ -254,23 +260,23 @@ static int arch_build_bp_info(struct perf_event *bp)
 		 * acceptable for kprobes.  On non-kprobes kernels, we don't
 		 * allow kernel breakpoints at all.
 		 */
-		if (bp->attr.bp_addr >= TASK_SIZE_MAX) {
+		if (attr->bp_addr >= TASK_SIZE_MAX) {
 #ifdef CONFIG_KPROBES
-			if (within_kprobe_blacklist(bp->attr.bp_addr))
+			if (within_kprobe_blacklist(attr->bp_addr))
 				return -EINVAL;
 #else
 			return -EINVAL;
 #endif
 		}
 
-		info->type = X86_BREAKPOINT_EXECUTE;
+		hw->type = X86_BREAKPOINT_EXECUTE;
 		/*
 		 * x86 inst breakpoints need to have a specific undefined len.
 		 * But we still need to check userspace is not trying to setup
 		 * an unsupported length, to get a range breakpoint for example.
 		 */
-		if (bp->attr.bp_len == sizeof(long)) {
-			info->len = X86_BREAKPOINT_LEN_X;
+		if (attr->bp_len == sizeof(long)) {
+			hw->len = X86_BREAKPOINT_LEN_X;
 			return 0;
 		}
 	default:
@@ -278,28 +284,26 @@ static int arch_build_bp_info(struct perf_event *bp)
 	}
 
 	/* Len */
-	info->mask = 0;
-
-	switch (bp->attr.bp_len) {
+	switch (attr->bp_len) {
 	case HW_BREAKPOINT_LEN_1:
-		info->len = X86_BREAKPOINT_LEN_1;
+		hw->len = X86_BREAKPOINT_LEN_1;
 		break;
 	case HW_BREAKPOINT_LEN_2:
-		info->len = X86_BREAKPOINT_LEN_2;
+		hw->len = X86_BREAKPOINT_LEN_2;
 		break;
 	case HW_BREAKPOINT_LEN_4:
-		info->len = X86_BREAKPOINT_LEN_4;
+		hw->len = X86_BREAKPOINT_LEN_4;
 		break;
 #ifdef CONFIG_X86_64
 	case HW_BREAKPOINT_LEN_8:
-		info->len = X86_BREAKPOINT_LEN_8;
+		hw->len = X86_BREAKPOINT_LEN_8;
 		break;
 #endif
 	default:
 		/* AMD range breakpoint */
-		if (!is_power_of_2(bp->attr.bp_len))
+		if (!is_power_of_2(attr->bp_len))
 			return -EINVAL;
-		if (bp->attr.bp_addr & (bp->attr.bp_len - 1))
+		if (attr->bp_addr & (attr->bp_len - 1))
 			return -EINVAL;
 
 		if (!boot_cpu_has(X86_FEATURE_BPEXT))
@@ -312,8 +316,8 @@ static int arch_build_bp_info(struct perf_event *bp)
 		 * breakpoints, then we'll have to check for kprobe-blacklisted
 		 * addresses anywhere in the range.
 		 */
-		info->mask = bp->attr.bp_len - 1;
-		info->len = X86_BREAKPOINT_LEN_1;
+		hw->mask = attr->bp_len - 1;
+		hw->len = X86_BREAKPOINT_LEN_1;
 	}
 
 	return 0;
@@ -322,22 +326,23 @@ static int arch_build_bp_info(struct perf_event *bp)
 /*
  * Validate the arch-specific HW Breakpoint register settings
  */
-int arch_validate_hwbkpt_settings(struct perf_event *bp)
+int hw_breakpoint_arch_parse(struct perf_event *bp,
+			     const struct perf_event_attr *attr,
+			     struct arch_hw_breakpoint *hw)
 {
-	struct arch_hw_breakpoint *info = counter_arch_bp(bp);
 	unsigned int align;
 	int ret;
 
 
-	ret = arch_build_bp_info(bp);
+	ret = arch_build_bp_info(bp, attr, hw);
 	if (ret)
 		return ret;
 
-	switch (info->len) {
+	switch (hw->len) {
 	case X86_BREAKPOINT_LEN_1:
 		align = 0;
-		if (info->mask)
-			align = info->mask;
+		if (hw->mask)
+			align = hw->mask;
 		break;
 	case X86_BREAKPOINT_LEN_2:
 		align = 1;
@@ -358,7 +363,7 @@ int arch_validate_hwbkpt_settings(struct perf_event *bp)
 	 * Check that the low-order bits of the address are appropriate
 	 * for the alignment implied by len.
 	 */
-	if (info->address & align)
+	if (hw->address & align)
 		return -EINVAL;
 
 	return 0;

arch/x86/kernel/kprobes/common.h

@@ -105,14 +105,4 @@ static inline unsigned long __recover_optprobed_insn(kprobe_opcode_t *buf, unsig
 }
 #endif
 
-#ifdef CONFIG_KPROBES_ON_FTRACE
-extern int skip_singlestep(struct kprobe *p, struct pt_regs *regs,
-			   struct kprobe_ctlblk *kcb);
-#else
-static inline int skip_singlestep(struct kprobe *p, struct pt_regs *regs,
-				  struct kprobe_ctlblk *kcb)
-{
-	return 0;
-}
-#endif
 #endif

arch/x86/kernel/kprobes/core.c

@@ -66,8 +66,6 @@
 
 #include "common.h"
 
-void jprobe_return_end(void);
-
 DEFINE_PER_CPU(struct kprobe *, current_kprobe) = NULL;
 DEFINE_PER_CPU(struct kprobe_ctlblk, kprobe_ctlblk);
 
@@ -395,8 +393,6 @@ int __copy_instruction(u8 *dest, u8 *src, u8 *real, struct insn *insn)
 			  - (u8 *) real;
 		if ((s64) (s32) newdisp != newdisp) {
 			pr_err("Kprobes error: new displacement does not fit into s32 (%llx)\n", newdisp);
-			pr_err("\tSrc: %p, Dest: %p, old disp: %x\n",
-				src, real, insn->displacement.value);
 			return 0;
 		}
 		disp = (u8 *) dest + insn_offset_displacement(insn);
@@ -596,7 +592,6 @@ static void setup_singlestep(struct kprobe *p, struct pt_regs *regs,
 		 * stepping.
 		 */
 		regs->ip = (unsigned long)p->ainsn.insn;
-		preempt_enable_no_resched();
 		return;
 	}
 #endif
@@ -640,8 +635,7 @@ static int reenter_kprobe(struct kprobe *p, struct pt_regs *regs,
 		 * Raise a BUG or we'll continue in an endless reentering loop
 		 * and eventually a stack overflow.
 		 */
-		printk(KERN_WARNING "Unrecoverable kprobe detected at %p.\n",
-		       p->addr);
+		pr_err("Unrecoverable kprobe detected.\n");
 		dump_kprobe(p);
 		BUG();
 	default:
@@ -669,12 +663,10 @@ int kprobe_int3_handler(struct pt_regs *regs)
 
 	addr = (kprobe_opcode_t *)(regs->ip - sizeof(kprobe_opcode_t));
 	/*
-	 * We don't want to be preempted for the entire
-	 * duration of kprobe processing. We conditionally
-	 * re-enable preemption at the end of this function,
-	 * and also in reenter_kprobe() and setup_singlestep().
+	 * We don't want to be preempted for the entire duration of kprobe
+	 * processing. Since int3 and debug trap disables irqs and we clear
+	 * IF while singlestepping, it must be no preemptible.
 	 */
-	preempt_disable();
 
 	kcb = get_kprobe_ctlblk();
 	p = get_kprobe(addr);
@@ -690,13 +682,14 @@ int kprobe_int3_handler(struct pt_regs *regs)
 			/*
 			 * If we have no pre-handler or it returned 0, we
 			 * continue with normal processing.  If we have a
-			 * pre-handler and it returned non-zero, it prepped
-			 * for calling the break_handler below on re-entry
-			 * for jprobe processing, so get out doing nothing
-			 * more here.
+			 * pre-handler and it returned non-zero, that means
+			 * user handler setup registers to exit to another
+			 * instruction, we must skip the single stepping.
 			 */
 			if (!p->pre_handler || !p->pre_handler(p, regs))
 				setup_singlestep(p, regs, kcb, 0);
+			else
+				reset_current_kprobe();
 			return 1;
 		}
 	} else if (*addr != BREAKPOINT_INSTRUCTION) {
@@ -710,18 +703,9 @@ int kprobe_int3_handler(struct pt_regs *regs)
 		 * the original instruction.
 		 */
 		regs->ip = (unsigned long)addr;
-		preempt_enable_no_resched();
 		return 1;
-	} else if (kprobe_running()) {
-		p = __this_cpu_read(current_kprobe);
-		if (p->break_handler && p->break_handler(p, regs)) {
-			if (!skip_singlestep(p, regs, kcb))
-				setup_singlestep(p, regs, kcb, 0);
-			return 1;
-		}
 	} /* else: not a kprobe fault; let the kernel handle it */
 
-	preempt_enable_no_resched();
 	return 0;
 }
 NOKPROBE_SYMBOL(kprobe_int3_handler);
@@ -972,8 +956,6 @@ int kprobe_debug_handler(struct pt_regs *regs)
 	}
 	reset_current_kprobe();
 out:
-	preempt_enable_no_resched();
-
 	/*
 	 * if somebody else is singlestepping across a probe point, flags
 	 * will have TF set, in which case, continue the remaining processing
@@ -1020,7 +1002,6 @@ int kprobe_fault_handler(struct pt_regs *regs, int trapnr)
 			restore_previous_kprobe(kcb);
 		else
 			reset_current_kprobe();
-		preempt_enable_no_resched();
 	} else if (kcb->kprobe_status == KPROBE_HIT_ACTIVE ||
 		   kcb->kprobe_status == KPROBE_HIT_SSDONE) {
 		/*
@@ -1083,93 +1064,6 @@ int kprobe_exceptions_notify(struct notifier_block *self, unsigned long val,
 }
 NOKPROBE_SYMBOL(kprobe_exceptions_notify);
 
-int setjmp_pre_handler(struct kprobe *p, struct pt_regs *regs)
-{
-	struct jprobe *jp = container_of(p, struct jprobe, kp);
-	unsigned long addr;
-	struct kprobe_ctlblk *kcb = get_kprobe_ctlblk();
-
-	kcb->jprobe_saved_regs = *regs;
-	kcb->jprobe_saved_sp = stack_addr(regs);
-	addr = (unsigned long)(kcb->jprobe_saved_sp);
-
-	/*
-	 * As Linus pointed out, gcc assumes that the callee
-	 * owns the argument space and could overwrite it, e.g.
-	 * tailcall optimization. So, to be absolutely safe
-	 * we also save and restore enough stack bytes to cover
-	 * the argument area.
-	 * Use __memcpy() to avoid KASAN stack out-of-bounds reports as we copy
-	 * raw stack chunk with redzones:
-	 */
-	__memcpy(kcb->jprobes_stack, (kprobe_opcode_t *)addr, MIN_STACK_SIZE(addr));
-	regs->ip = (unsigned long)(jp->entry);
-
-	/*
-	 * jprobes use jprobe_return() which skips the normal return
-	 * path of the function, and this messes up the accounting of the
-	 * function graph tracer to get messed up.
-	 *
-	 * Pause function graph tracing while performing the jprobe function.
-	 */
-	pause_graph_tracing();
-	return 1;
-}
-NOKPROBE_SYMBOL(setjmp_pre_handler);
-
-void jprobe_return(void)
-{
-	struct kprobe_ctlblk *kcb = get_kprobe_ctlblk();
-
-	/* Unpoison stack redzones in the frames we are going to jump over. */
-	kasan_unpoison_stack_above_sp_to(kcb->jprobe_saved_sp);
-
-	asm volatile (
-#ifdef CONFIG_X86_64
-			"       xchg   %%rbx,%%rsp	\n"
-#else
-			"       xchgl   %%ebx,%%esp	\n"
-#endif
-			"       int3			\n"
-			"       .globl jprobe_return_end\n"
-			"       jprobe_return_end:	\n"
-			"       nop			\n"::"b"
-			(kcb->jprobe_saved_sp):"memory");
-}
-NOKPROBE_SYMBOL(jprobe_return);
-NOKPROBE_SYMBOL(jprobe_return_end);
-
-int longjmp_break_handler(struct kprobe *p, struct pt_regs *regs)
-{
-	struct kprobe_ctlblk *kcb = get_kprobe_ctlblk();
-	u8 *addr = (u8 *) (regs->ip - 1);
-	struct jprobe *jp = container_of(p, struct jprobe, kp);
-	void *saved_sp = kcb->jprobe_saved_sp;
-
-	if ((addr > (u8 *) jprobe_return) &&
-	    (addr < (u8 *) jprobe_return_end)) {
-		if (stack_addr(regs) != saved_sp) {
-			struct pt_regs *saved_regs = &kcb->jprobe_saved_regs;
-			printk(KERN_ERR
-			       "current sp %p does not match saved sp %p\n",
-			       stack_addr(regs), saved_sp);
-			printk(KERN_ERR "Saved registers for jprobe %p\n", jp);
-			show_regs(saved_regs);
-			printk(KERN_ERR "Current registers\n");
-			show_regs(regs);
-			BUG();
-		}
-		/* It's OK to start function graph tracing again */
-		unpause_graph_tracing();
-		*regs = kcb->jprobe_saved_regs;
-		__memcpy(saved_sp, kcb->jprobes_stack, MIN_STACK_SIZE(saved_sp));
-		preempt_enable_no_resched();
-		return 1;
-	}
-	return 0;
-}
-NOKPROBE_SYMBOL(longjmp_break_handler);
-
 bool arch_within_kprobe_blacklist(unsigned long addr)
 {
 	bool is_in_entry_trampoline_section = false;

arch/x86/kernel/kprobes/ftrace.c

@@ -25,36 +25,6 @@
 
 #include "common.h"
 
-static nokprobe_inline
-void __skip_singlestep(struct kprobe *p, struct pt_regs *regs,
-		      struct kprobe_ctlblk *kcb, unsigned long orig_ip)
-{
-	/*
-	 * Emulate singlestep (and also recover regs->ip)
-	 * as if there is a 5byte nop
-	 */
-	regs->ip = (unsigned long)p->addr + MCOUNT_INSN_SIZE;
-	if (unlikely(p->post_handler)) {
-		kcb->kprobe_status = KPROBE_HIT_SSDONE;
-		p->post_handler(p, regs, 0);
-	}
-	__this_cpu_write(current_kprobe, NULL);
-	if (orig_ip)
-		regs->ip = orig_ip;
-}
-
-int skip_singlestep(struct kprobe *p, struct pt_regs *regs,
-		    struct kprobe_ctlblk *kcb)
-{
-	if (kprobe_ftrace(p)) {
-		__skip_singlestep(p, regs, kcb, 0);
-		preempt_enable_no_resched();
-		return 1;
-	}
-	return 0;
-}
-NOKPROBE_SYMBOL(skip_singlestep);
-
 /* Ftrace callback handler for kprobes -- called under preepmt disabed */
 void kprobe_ftrace_handler(unsigned long ip, unsigned long parent_ip,
 			   struct ftrace_ops *ops, struct pt_regs *regs)
@@ -75,18 +45,25 @@ void kprobe_ftrace_handler(unsigned long ip, unsigned long parent_ip,
 		/* Kprobe handler expects regs->ip = ip + 1 as breakpoint hit */
 		regs->ip = ip + sizeof(kprobe_opcode_t);
 
-		/* To emulate trap based kprobes, preempt_disable here */
-		preempt_disable();
 		__this_cpu_write(current_kprobe, p);
 		kcb->kprobe_status = KPROBE_HIT_ACTIVE;
 		if (!p->pre_handler || !p->pre_handler(p, regs)) {
-			__skip_singlestep(p, regs, kcb, orig_ip);
-			preempt_enable_no_resched();
+			/*
+			 * Emulate singlestep (and also recover regs->ip)
+			 * as if there is a 5byte nop
+			 */
+			regs->ip = (unsigned long)p->addr + MCOUNT_INSN_SIZE;
+			if (unlikely(p->post_handler)) {
+				kcb->kprobe_status = KPROBE_HIT_SSDONE;
+				p->post_handler(p, regs, 0);
+			}
+			regs->ip = orig_ip;
 		}
 		/*
-		 * If pre_handler returns !0, it sets regs->ip and
-		 * resets current kprobe, and keep preempt count +1.
+		 * If pre_handler returns !0, it changes regs->ip. We have to
+		 * skip emulating post_handler.
 		 */
+		__this_cpu_write(current_kprobe, NULL);
 	}
 }
 NOKPROBE_SYMBOL(kprobe_ftrace_handler);

arch/x86/kernel/kprobes/opt.c

@@ -491,7 +491,6 @@ int setup_detour_execution(struct kprobe *p, struct pt_regs *regs, int reenter)
 		regs->ip = (unsigned long)op->optinsn.insn + TMPL_END_IDX;
 		if (!reenter)
 			reset_current_kprobe();
-		preempt_enable_no_resched();
 		return 1;
 	}
 	return 0;

arch/xtensa/include/asm/hw_breakpoint.h

@@ -30,13 +30,16 @@ struct arch_hw_breakpoint {
 	u16 type;
 };
 
+struct perf_event_attr;
 struct perf_event;
 struct pt_regs;
 struct task_struct;
 
 int hw_breakpoint_slots(int type);
-int arch_check_bp_in_kernelspace(struct perf_event *bp);
-int arch_validate_hwbkpt_settings(struct perf_event *bp);
+int arch_check_bp_in_kernelspace(struct arch_hw_breakpoint *hw);
+int hw_breakpoint_arch_parse(struct perf_event *bp,
+			     const struct perf_event_attr *attr,
+			     struct arch_hw_breakpoint *hw);
 int hw_breakpoint_exceptions_notify(struct notifier_block *unused,
 				    unsigned long val, void *data);
 

arch/xtensa/kernel/hw_breakpoint.c

@@ -33,14 +33,13 @@ int hw_breakpoint_slots(int type)
 	}
 }
 
-int arch_check_bp_in_kernelspace(struct perf_event *bp)
+int arch_check_bp_in_kernelspace(struct arch_hw_breakpoint *hw)
 {
 	unsigned int len;
 	unsigned long va;
-	struct arch_hw_breakpoint *info = counter_arch_bp(bp);
 
-	va = info->address;
-	len = bp->attr.bp_len;
+	va = hw->address;
+	len = hw->len;
 
 	return (va >= TASK_SIZE) && ((va + len - 1) >= TASK_SIZE);
 }
@@ -48,50 +47,41 @@ int arch_check_bp_in_kernelspace(struct perf_event *bp)
 /*
  * Construct an arch_hw_breakpoint from a perf_event.
  */
-static int arch_build_bp_info(struct perf_event *bp)
+int hw_breakpoint_arch_parse(struct perf_event *bp,
+			     const struct perf_event_attr *attr,
+			     struct arch_hw_breakpoint *hw)
 {
-	struct arch_hw_breakpoint *info = counter_arch_bp(bp);
-
 	/* Type */
-	switch (bp->attr.bp_type) {
+	switch (attr->bp_type) {
 	case HW_BREAKPOINT_X:
-		info->type = XTENSA_BREAKPOINT_EXECUTE;
+		hw->type = XTENSA_BREAKPOINT_EXECUTE;
 		break;
 	case HW_BREAKPOINT_R:
-		info->type = XTENSA_BREAKPOINT_LOAD;
+		hw->type = XTENSA_BREAKPOINT_LOAD;
 		break;
 	case HW_BREAKPOINT_W:
-		info->type = XTENSA_BREAKPOINT_STORE;
+		hw->type = XTENSA_BREAKPOINT_STORE;
 		break;
 	case HW_BREAKPOINT_RW:
-		info->type = XTENSA_BREAKPOINT_LOAD | XTENSA_BREAKPOINT_STORE;
+		hw->type = XTENSA_BREAKPOINT_LOAD | XTENSA_BREAKPOINT_STORE;
 		break;
 	default:
 		return -EINVAL;
 	}
 
 	/* Len */
-	info->len = bp->attr.bp_len;
-	if (info->len < 1 || info->len > 64 || !is_power_of_2(info->len))
+	hw->len = attr->bp_len;
+	if (hw->len < 1 || hw->len > 64 || !is_power_of_2(hw->len))
 		return -EINVAL;
 
 	/* Address */
-	info->address = bp->attr.bp_addr;
-	if (info->address & (info->len - 1))
+	hw->address = attr->bp_addr;
+	if (hw->address & (hw->len - 1))
 		return -EINVAL;
 
 	return 0;
 }
 
-int arch_validate_hwbkpt_settings(struct perf_event *bp)
-{
-	int ret;
-
-	/* Build the arch_hw_breakpoint. */
-	ret = arch_build_bp_info(bp);
-	return ret;
-}
-
 int hw_breakpoint_exceptions_notify(struct notifier_block *unused,
 				    unsigned long val, void *data)
 {

include/linux/kprobes.h

@@ -63,7 +63,6 @@ struct pt_regs;
 struct kretprobe;
 struct kretprobe_instance;
 typedef int (*kprobe_pre_handler_t) (struct kprobe *, struct pt_regs *);
-typedef int (*kprobe_break_handler_t) (struct kprobe *, struct pt_regs *);
 typedef void (*kprobe_post_handler_t) (struct kprobe *, struct pt_regs *,
 				       unsigned long flags);
 typedef int (*kprobe_fault_handler_t) (struct kprobe *, struct pt_regs *,
@@ -101,12 +100,6 @@ struct kprobe {
 	 */
 	kprobe_fault_handler_t fault_handler;
 
-	/*
-	 * ... called if breakpoint trap occurs in probe handler.
-	 * Return 1 if it handled break, otherwise kernel will see it.
-	 */
-	kprobe_break_handler_t break_handler;
-
 	/* Saved opcode (which has been replaced with breakpoint) */
 	kprobe_opcode_t opcode;
 
@@ -154,24 +147,6 @@ static inline int kprobe_ftrace(struct kprobe *p)
 	return p->flags & KPROBE_FLAG_FTRACE;
 }
 
-/*
- * Special probe type that uses setjmp-longjmp type tricks to resume
- * execution at a specified entry with a matching prototype corresponding
- * to the probed function - a trick to enable arguments to become
- * accessible seamlessly by probe handling logic.
- * Note:
- * Because of the way compilers allocate stack space for local variables
- * etc upfront, regardless of sub-scopes within a function, this mirroring
- * principle currently works only for probes placed on function entry points.
- */
-struct jprobe {
-	struct kprobe kp;
-	void *entry;	/* probe handling code to jump to */
-};
-
-/* For backward compatibility with old code using JPROBE_ENTRY() */
-#define JPROBE_ENTRY(handler)	(handler)
-
 /*
  * Function-return probe -
  * Note:
@@ -389,9 +364,6 @@ int register_kprobe(struct kprobe *p);
 void unregister_kprobe(struct kprobe *p);
 int register_kprobes(struct kprobe **kps, int num);
 void unregister_kprobes(struct kprobe **kps, int num);
-int setjmp_pre_handler(struct kprobe *, struct pt_regs *);
-int longjmp_break_handler(struct kprobe *, struct pt_regs *);
-void jprobe_return(void);
 unsigned long arch_deref_entry_point(void *);
 
 int register_kretprobe(struct kretprobe *rp);
@@ -439,9 +411,6 @@ static inline void unregister_kprobe(struct kprobe *p)
 static inline void unregister_kprobes(struct kprobe **kps, int num)
 {
 }
-static inline void jprobe_return(void)
-{
-}
 static inline int register_kretprobe(struct kretprobe *rp)
 {
 	return -ENOSYS;
@@ -468,20 +437,6 @@ static inline int enable_kprobe(struct kprobe *kp)
 	return -ENOSYS;
 }
 #endif /* CONFIG_KPROBES */
-static inline int register_jprobe(struct jprobe *p)
-{
-	return -ENOSYS;
-}
-static inline int register_jprobes(struct jprobe **jps, int num)
-{
-	return -ENOSYS;
-}
-static inline void unregister_jprobe(struct jprobe *p)
-{
-}
-static inline void unregister_jprobes(struct jprobe **jps, int num)
-{
-}
 static inline int disable_kretprobe(struct kretprobe *rp)
 {
 	return disable_kprobe(&rp->kp);
@@ -490,14 +445,6 @@ static inline int enable_kretprobe(struct kretprobe *rp)
 {
 	return enable_kprobe(&rp->kp);
 }
-static inline int disable_jprobe(struct jprobe *jp)
-{
-	return -ENOSYS;
-}
-static inline int enable_jprobe(struct jprobe *jp)
-{
-	return -ENOSYS;
-}
 
 #ifndef CONFIG_KPROBES
 static inline bool is_kprobe_insn_slot(unsigned long addr)

include/linux/perf_event.h

@@ -490,7 +490,7 @@ struct perf_addr_filters_head {
 };
 
 /**
- * enum perf_event_state - the states of a event
+ * enum perf_event_state - the states of an event:
  */
 enum perf_event_state {
 	PERF_EVENT_STATE_DEAD		= -4,

kernel/events/core.c

@@ -1656,7 +1656,7 @@ perf_event_groups_next(struct perf_event *event)
 				typeof(*event), group_node))
 
 /*
- * Add a event from the lists for its context.
+ * Add an event from the lists for its context.
  * Must be called with ctx->mutex and ctx->lock held.
  */
 static void
@@ -1844,7 +1844,7 @@ static void perf_group_attach(struct perf_event *event)
 }
 
 /*
- * Remove a event from the lists for its context.
+ * Remove an event from the lists for its context.
  * Must be called with ctx->mutex and ctx->lock held.
  */
 static void
@@ -2148,7 +2148,7 @@ static void __perf_event_disable(struct perf_event *event,
 }
 
 /*
- * Disable a event.
+ * Disable an event.
  *
  * If event->ctx is a cloned context, callers must make sure that
  * every task struct that event->ctx->task could possibly point to
@@ -2677,7 +2677,7 @@ static void __perf_event_enable(struct perf_event *event,
 }
 
 /*
- * Enable a event.
+ * Enable an event.
  *
  * If event->ctx is a cloned context, callers must make sure that
  * every task struct that event->ctx->task could possibly point to
@@ -2755,7 +2755,7 @@ static int __perf_event_stop(void *info)
 	 * events will refuse to restart because of rb::aux_mmap_count==0,
 	 * see comments in perf_aux_output_begin().
 	 *
-	 * Since this is happening on a event-local CPU, no trace is lost
+	 * Since this is happening on an event-local CPU, no trace is lost
 	 * while restarting.
 	 */
 	if (sd->restart)
@@ -4827,7 +4827,7 @@ __perf_read(struct perf_event *event, char __user *buf, size_t count)
 	int ret;
 
 	/*
-	 * Return end-of-file for a read on a event that is in
+	 * Return end-of-file for a read on an event that is in
 	 * error state (i.e. because it was pinned but it couldn't be
 	 * scheduled on to the CPU at some point).
 	 */
@@ -5273,11 +5273,11 @@ void perf_event_update_userpage(struct perf_event *event)
 }
 EXPORT_SYMBOL_GPL(perf_event_update_userpage);
 
-static int perf_mmap_fault(struct vm_fault *vmf)
+static vm_fault_t perf_mmap_fault(struct vm_fault *vmf)
 {
 	struct perf_event *event = vmf->vma->vm_file->private_data;
 	struct ring_buffer *rb;
-	int ret = VM_FAULT_SIGBUS;
+	vm_fault_t ret = VM_FAULT_SIGBUS;
 
 	if (vmf->flags & FAULT_FLAG_MKWRITE) {
 		if (vmf->pgoff == 0)
@@ -9904,7 +9904,7 @@ static void account_event(struct perf_event *event)
 }
 
 /*
- * Allocate and initialize a event structure
+ * Allocate and initialize an event structure
  */
 static struct perf_event *
 perf_event_alloc(struct perf_event_attr *attr, int cpu,
@@ -11235,7 +11235,7 @@ const struct perf_event_attr *perf_event_attrs(struct perf_event *event)
 }
 
 /*
- * Inherit a event from parent task to child task.
+ * Inherit an event from parent task to child task.
  *
  * Returns:
  *  - valid pointer on success

kernel/events/hw_breakpoint.c

@@ -345,13 +345,13 @@ void release_bp_slot(struct perf_event *bp)
 	mutex_unlock(&nr_bp_mutex);
 }
 
-static int __modify_bp_slot(struct perf_event *bp, u64 old_type)
+static int __modify_bp_slot(struct perf_event *bp, u64 old_type, u64 new_type)
 {
 	int err;
 
 	__release_bp_slot(bp, old_type);
 
-	err = __reserve_bp_slot(bp, bp->attr.bp_type);
+	err = __reserve_bp_slot(bp, new_type);
 	if (err) {
 		/*
 		 * Reserve the old_type slot back in case
@@ -367,12 +367,12 @@ static int __modify_bp_slot(struct perf_event *bp, u64 old_type)
 	return err;
 }
 
-static int modify_bp_slot(struct perf_event *bp, u64 old_type)
+static int modify_bp_slot(struct perf_event *bp, u64 old_type, u64 new_type)
 {
 	int ret;
 
 	mutex_lock(&nr_bp_mutex);
-	ret = __modify_bp_slot(bp, old_type);
+	ret = __modify_bp_slot(bp, old_type, new_type);
 	mutex_unlock(&nr_bp_mutex);
 	return ret;
 }
@@ -400,16 +400,18 @@ int dbg_release_bp_slot(struct perf_event *bp)
 	return 0;
 }
 
-static int validate_hw_breakpoint(struct perf_event *bp)
+static int hw_breakpoint_parse(struct perf_event *bp,
+			       const struct perf_event_attr *attr,
+			       struct arch_hw_breakpoint *hw)
 {
-	int ret;
+	int err;
 
-	ret = arch_validate_hwbkpt_settings(bp);
-	if (ret)
-		return ret;
+	err = hw_breakpoint_arch_parse(bp, attr, hw);
+	if (err)
+		return err;
 
-	if (arch_check_bp_in_kernelspace(bp)) {
-		if (bp->attr.exclude_kernel)
+	if (arch_check_bp_in_kernelspace(hw)) {
+		if (attr->exclude_kernel)
 			return -EINVAL;
 		/*
 		 * Don't let unprivileged users set a breakpoint in the trap
@@ -424,19 +426,22 @@ static int validate_hw_breakpoint(struct perf_event *bp)
 
 int register_perf_hw_breakpoint(struct perf_event *bp)
 {
-	int ret;
-
-	ret = reserve_bp_slot(bp);
-	if (ret)
-		return ret;
+	struct arch_hw_breakpoint hw;
+	int err;
 
-	ret = validate_hw_breakpoint(bp);
+	err = reserve_bp_slot(bp);
+	if (err)
+		return err;
 
-	/* if arch_validate_hwbkpt_settings() fails then release bp slot */
-	if (ret)
+	err = hw_breakpoint_parse(bp, &bp->attr, &hw);
+	if (err) {
 		release_bp_slot(bp);
+		return err;
+	}
 
-	return ret;
+	bp->hw.info = hw;
+
+	return 0;
 }
 
 /**
@@ -456,35 +461,44 @@ register_user_hw_breakpoint(struct perf_event_attr *attr,
 }
 EXPORT_SYMBOL_GPL(register_user_hw_breakpoint);
 
+static void hw_breakpoint_copy_attr(struct perf_event_attr *to,
+				    struct perf_event_attr *from)
+{
+	to->bp_addr = from->bp_addr;
+	to->bp_type = from->bp_type;
+	to->bp_len  = from->bp_len;
+	to->disabled = from->disabled;
+}
+
 int
 modify_user_hw_breakpoint_check(struct perf_event *bp, struct perf_event_attr *attr,
 			        bool check)
 {
-	u64 old_addr = bp->attr.bp_addr;
-	u64 old_len  = bp->attr.bp_len;
-	int old_type = bp->attr.bp_type;
-	bool modify  = attr->bp_type != old_type;
-	int err = 0;
+	struct arch_hw_breakpoint hw;
+	int err;
 
-	bp->attr.bp_addr = attr->bp_addr;
-	bp->attr.bp_type = attr->bp_type;
-	bp->attr.bp_len  = attr->bp_len;
+	err = hw_breakpoint_parse(bp, attr, &hw);
+	if (err)
+		return err;
 
-	if (check && memcmp(&bp->attr, attr, sizeof(*attr)))
-		return -EINVAL;
+	if (check) {
+		struct perf_event_attr old_attr;
 
-	err = validate_hw_breakpoint(bp);
-	if (!err && modify)
-		err = modify_bp_slot(bp, old_type);
+		old_attr = bp->attr;
+		hw_breakpoint_copy_attr(&old_attr, attr);
+		if (memcmp(&old_attr, attr, sizeof(*attr)))
+			return -EINVAL;
+	}
 
-	if (err) {
-		bp->attr.bp_addr = old_addr;
-		bp->attr.bp_type = old_type;
-		bp->attr.bp_len  = old_len;
-		return err;
+	if (bp->attr.bp_type != attr->bp_type) {
+		err = modify_bp_slot(bp, bp->attr.bp_type, attr->bp_type);
+		if (err)
+			return err;
 	}
 
-	bp->attr.disabled = attr->disabled;
+	hw_breakpoint_copy_attr(&bp->attr, attr);
+	bp->hw.info = hw;
+
 	return 0;
 }
 

kernel/events/uprobes.c

@@ -918,7 +918,7 @@ int uprobe_register(struct inode *inode, loff_t offset, struct uprobe_consumer *
 EXPORT_SYMBOL_GPL(uprobe_register);
 
 /*
- * uprobe_apply - unregister a already registered probe.
+ * uprobe_apply - unregister an already registered probe.
  * @inode: the file in which the probe has to be removed.
  * @offset: offset from the start of the file.
  * @uc: consumer which wants to add more or remove some breakpoints
@@ -947,7 +947,7 @@ int uprobe_apply(struct inode *inode, loff_t offset,
 }
 
 /*
- * uprobe_unregister - unregister a already registered probe.
+ * uprobe_unregister - unregister an already registered probe.
  * @inode: the file in which the probe has to be removed.
  * @offset: offset from the start of the file.
  * @uc: identify which probe if multiple probes are colocated.
@@ -1403,7 +1403,7 @@ static struct return_instance *free_ret_instance(struct return_instance *ri)
 
 /*
  * Called with no locks held.
- * Called in context of a exiting or a exec-ing thread.
+ * Called in context of an exiting or an exec-ing thread.
  */
 void uprobe_free_utask(struct task_struct *t)
 {

kernel/fail_function.c

@@ -184,9 +184,6 @@ static int fei_kprobe_handler(struct kprobe *kp, struct pt_regs *regs)
 	if (should_fail(&fei_fault_attr, 1)) {
 		regs_set_return_value(regs, attr->retval);
 		override_function_with_return(regs);
-		/* Kprobe specific fixup */
-		reset_current_kprobe();
-		preempt_enable_no_resched();
 		return 1;
 	}
 

kernel/kprobes.c

@@ -627,8 +627,8 @@ static void optimize_kprobe(struct kprobe *p)
 	    (kprobe_disabled(p) || kprobes_all_disarmed))
 		return;
 
-	/* Both of break_handler and post_handler are not supported. */
-	if (p->break_handler || p->post_handler)
+	/* kprobes with post_handler can not be optimized */
+	if (p->post_handler)
 		return;
 
 	op = container_of(p, struct optimized_kprobe, kp);
@@ -710,9 +710,7 @@ static void reuse_unused_kprobe(struct kprobe *ap)
 	 * there is still a relative jump) and disabled.
 	 */
 	op = container_of(ap, struct optimized_kprobe, kp);
-	if (unlikely(list_empty(&op->list)))
-		printk(KERN_WARNING "Warning: found a stray unused "
-			"aggrprobe@%p\n", ap->addr);
+	WARN_ON_ONCE(list_empty(&op->list));
 	/* Enable the probe again */
 	ap->flags &= ~KPROBE_FLAG_DISABLED;
 	/* Optimize it again (remove from op->list) */
@@ -985,7 +983,8 @@ static int arm_kprobe_ftrace(struct kprobe *p)
 	ret = ftrace_set_filter_ip(&kprobe_ftrace_ops,
 				   (unsigned long)p->addr, 0, 0);
 	if (ret) {
-		pr_debug("Failed to arm kprobe-ftrace at %p (%d)\n", p->addr, ret);
+		pr_debug("Failed to arm kprobe-ftrace at %pS (%d)\n",
+			 p->addr, ret);
 		return ret;
 	}
 
@@ -1025,7 +1024,8 @@ static int disarm_kprobe_ftrace(struct kprobe *p)
 
 	ret = ftrace_set_filter_ip(&kprobe_ftrace_ops,
 			   (unsigned long)p->addr, 1, 0);
-	WARN(ret < 0, "Failed to disarm kprobe-ftrace at %p (%d)\n", p->addr, ret);
+	WARN_ONCE(ret < 0, "Failed to disarm kprobe-ftrace at %pS (%d)\n",
+		  p->addr, ret);
 	return ret;
 }
 #else	/* !CONFIG_KPROBES_ON_FTRACE */
@@ -1116,20 +1116,6 @@ static int aggr_fault_handler(struct kprobe *p, struct pt_regs *regs,
 }
 NOKPROBE_SYMBOL(aggr_fault_handler);
 
-static int aggr_break_handler(struct kprobe *p, struct pt_regs *regs)
-{
-	struct kprobe *cur = __this_cpu_read(kprobe_instance);
-	int ret = 0;
-
-	if (cur && cur->break_handler) {
-		if (cur->break_handler(cur, regs))
-			ret = 1;
-	}
-	reset_kprobe_instance();
-	return ret;
-}
-NOKPROBE_SYMBOL(aggr_break_handler);
-
 /* Walks the list and increments nmissed count for multiprobe case */
 void kprobes_inc_nmissed_count(struct kprobe *p)
 {
@@ -1270,24 +1256,15 @@ static void cleanup_rp_inst(struct kretprobe *rp)
 }
 NOKPROBE_SYMBOL(cleanup_rp_inst);
 
-/*
-* Add the new probe to ap->list. Fail if this is the
-* second jprobe at the address - two jprobes can't coexist
-*/
+/* Add the new probe to ap->list */
 static int add_new_kprobe(struct kprobe *ap, struct kprobe *p)
 {
 	BUG_ON(kprobe_gone(ap) || kprobe_gone(p));
 
-	if (p->break_handler || p->post_handler)
+	if (p->post_handler)
 		unoptimize_kprobe(ap, true);	/* Fall back to normal kprobe */
 
-	if (p->break_handler) {
-		if (ap->break_handler)
-			return -EEXIST;
-		list_add_tail_rcu(&p->list, &ap->list);
-		ap->break_handler = aggr_break_handler;
-	} else
-		list_add_rcu(&p->list, &ap->list);
+	list_add_rcu(&p->list, &ap->list);
 	if (p->post_handler && !ap->post_handler)
 		ap->post_handler = aggr_post_handler;
 
@@ -1310,8 +1287,6 @@ static void init_aggr_kprobe(struct kprobe *ap, struct kprobe *p)
 	/* We don't care the kprobe which has gone. */
 	if (p->post_handler && !kprobe_gone(p))
 		ap->post_handler = aggr_post_handler;
-	if (p->break_handler && !kprobe_gone(p))
-		ap->break_handler = aggr_break_handler;
 
 	INIT_LIST_HEAD(&ap->list);
 	INIT_HLIST_NODE(&ap->hlist);
@@ -1706,8 +1681,6 @@ static int __unregister_kprobe_top(struct kprobe *p)
 		goto disarmed;
 	else {
 		/* If disabling probe has special handlers, update aggrprobe */
-		if (p->break_handler && !kprobe_gone(p))
-			ap->break_handler = NULL;
 		if (p->post_handler && !kprobe_gone(p)) {
 			list_for_each_entry_rcu(list_p, &ap->list, list) {
 				if ((list_p != p) && (list_p->post_handler))
@@ -1812,77 +1785,6 @@ unsigned long __weak arch_deref_entry_point(void *entry)
 	return (unsigned long)entry;
 }
 
-#if 0
-int register_jprobes(struct jprobe **jps, int num)
-{
-	int ret = 0, i;
-
-	if (num <= 0)
-		return -EINVAL;
-
-	for (i = 0; i < num; i++) {
-		ret = register_jprobe(jps[i]);
-
-		if (ret < 0) {
-			if (i > 0)
-				unregister_jprobes(jps, i);
-			break;
-		}
-	}
-
-	return ret;
-}
-EXPORT_SYMBOL_GPL(register_jprobes);
-
-int register_jprobe(struct jprobe *jp)
-{
-	unsigned long addr, offset;
-	struct kprobe *kp = &jp->kp;
-
-	/*
-	 * Verify probepoint as well as the jprobe handler are
-	 * valid function entry points.
-	 */
-	addr = arch_deref_entry_point(jp->entry);
-
-	if (kallsyms_lookup_size_offset(addr, NULL, &offset) && offset == 0 &&
-	    kprobe_on_func_entry(kp->addr, kp->symbol_name, kp->offset)) {
-		kp->pre_handler = setjmp_pre_handler;
-		kp->break_handler = longjmp_break_handler;
-		return register_kprobe(kp);
-	}
-
-	return -EINVAL;
-}
-EXPORT_SYMBOL_GPL(register_jprobe);
-
-void unregister_jprobe(struct jprobe *jp)
-{
-	unregister_jprobes(&jp, 1);
-}
-EXPORT_SYMBOL_GPL(unregister_jprobe);
-
-void unregister_jprobes(struct jprobe **jps, int num)
-{
-	int i;
-
-	if (num <= 0)
-		return;
-	mutex_lock(&kprobe_mutex);
-	for (i = 0; i < num; i++)
-		if (__unregister_kprobe_top(&jps[i]->kp) < 0)
-			jps[i]->kp.addr = NULL;
-	mutex_unlock(&kprobe_mutex);
-
-	synchronize_sched();
-	for (i = 0; i < num; i++) {
-		if (jps[i]->kp.addr)
-			__unregister_kprobe_bottom(&jps[i]->kp);
-	}
-}
-EXPORT_SYMBOL_GPL(unregister_jprobes);
-#endif
-
 #ifdef CONFIG_KRETPROBES
 /*
  * This kprobe pre_handler is registered with every kretprobe. When probe
@@ -1982,7 +1884,6 @@ int register_kretprobe(struct kretprobe *rp)
 	rp->kp.pre_handler = pre_handler_kretprobe;
 	rp->kp.post_handler = NULL;
 	rp->kp.fault_handler = NULL;
-	rp->kp.break_handler = NULL;
 
 	/* Pre-allocate memory for max kretprobe instances */
 	if (rp->maxactive <= 0) {
@@ -2105,7 +2006,6 @@ static void kill_kprobe(struct kprobe *p)
 		list_for_each_entry_rcu(kp, &p->list, list)
 			kp->flags |= KPROBE_FLAG_GONE;
 		p->post_handler = NULL;
-		p->break_handler = NULL;
 		kill_optimized_kprobe(p);
 	}
 	/*
@@ -2169,11 +2069,12 @@ int enable_kprobe(struct kprobe *kp)
 }
 EXPORT_SYMBOL_GPL(enable_kprobe);
 
+/* Caller must NOT call this in usual path. This is only for critical case */
 void dump_kprobe(struct kprobe *kp)
 {
-	printk(KERN_WARNING "Dumping kprobe:\n");
-	printk(KERN_WARNING "Name: %s\nAddress: %p\nOffset: %x\n",
-	       kp->symbol_name, kp->addr, kp->offset);
+	pr_err("Dumping kprobe:\n");
+	pr_err("Name: %s\nOffset: %x\nAddress: %pS\n",
+	       kp->symbol_name, kp->offset, kp->addr);
 }
 NOKPROBE_SYMBOL(dump_kprobe);
 
@@ -2196,11 +2097,8 @@ static int __init populate_kprobe_blacklist(unsigned long *start,
 		entry = arch_deref_entry_point((void *)*iter);
 
 		if (!kernel_text_address(entry) ||
-		    !kallsyms_lookup_size_offset(entry, &size, &offset)) {
-			pr_err("Failed to find blacklist at %p\n",
-				(void *)entry);
+		    !kallsyms_lookup_size_offset(entry, &size, &offset))
 			continue;
-		}
 
 		ent = kmalloc(sizeof(*ent), GFP_KERNEL);
 		if (!ent)
@@ -2326,21 +2224,23 @@ static void report_probe(struct seq_file *pi, struct kprobe *p,
 		const char *sym, int offset, char *modname, struct kprobe *pp)
 {
 	char *kprobe_type;
+	void *addr = p->addr;
 
 	if (p->pre_handler == pre_handler_kretprobe)
 		kprobe_type = "r";
-	else if (p->pre_handler == setjmp_pre_handler)
-		kprobe_type = "j";
 	else
 		kprobe_type = "k";
 
+	if (!kallsyms_show_value())
+		addr = NULL;
+
 	if (sym)
-		seq_printf(pi, "%p  %s  %s+0x%x  %s ",
-			p->addr, kprobe_type, sym, offset,
+		seq_printf(pi, "%px  %s  %s+0x%x  %s ",
+			addr, kprobe_type, sym, offset,
 			(modname ? modname : " "));
-	else
-		seq_printf(pi, "%p  %s  %p ",
-			p->addr, kprobe_type, p->addr);
+	else	/* try to use %pS */
+		seq_printf(pi, "%px  %s  %pS ",
+			addr, kprobe_type, p->addr);
 
 	if (!pp)
 		pp = p;
@@ -2428,8 +2328,16 @@ static int kprobe_blacklist_seq_show(struct seq_file *m, void *v)
 	struct kprobe_blacklist_entry *ent =
 		list_entry(v, struct kprobe_blacklist_entry, list);
 
-	seq_printf(m, "0x%px-0x%px\t%ps\n", (void *)ent->start_addr,
-		   (void *)ent->end_addr, (void *)ent->start_addr);
+	/*
+	 * If /proc/kallsyms is not showing kernel address, we won't
+	 * show them here either.
+	 */
+	if (!kallsyms_show_value())
+		seq_printf(m, "0x%px-0x%px\t%ps\n", NULL, NULL,
+			   (void *)ent->start_addr);
+	else
+		seq_printf(m, "0x%px-0x%px\t%ps\n", (void *)ent->start_addr,
+			   (void *)ent->end_addr, (void *)ent->start_addr);
 	return 0;
 }
 
@@ -2611,7 +2519,7 @@ static int __init debugfs_kprobe_init(void)
 	if (!dir)
 		return -ENOMEM;
 
-	file = debugfs_create_file("list", 0444, dir, NULL,
+	file = debugfs_create_file("list", 0400, dir, NULL,
 				&debugfs_kprobes_operations);
 	if (!file)
 		goto error;
@@ -2621,7 +2529,7 @@ static int __init debugfs_kprobe_init(void)
 	if (!file)
 		goto error;
 
-	file = debugfs_create_file("blacklist", 0444, dir, NULL,
+	file = debugfs_create_file("blacklist", 0400, dir, NULL,
 				&debugfs_kprobe_blacklist_ops);
 	if (!file)
 		goto error;
@@ -2637,6 +2545,3 @@ late_initcall(debugfs_kprobe_init);
 #endif /* CONFIG_DEBUG_FS */
 
 module_init(init_kprobes);
-
-/* defined in arch/.../kernel/kprobes.c */
-EXPORT_SYMBOL_GPL(jprobe_return);

kernel/test_kprobes.c

@@ -162,90 +162,6 @@ static int test_kprobes(void)
 
 }
 
-#if 0
-static u32 jph_val;
-
-static u32 j_kprobe_target(u32 value)
-{
-	if (preemptible()) {
-		handler_errors++;
-		pr_err("jprobe-handler is preemptible\n");
-	}
-	if (value != rand1) {
-		handler_errors++;
-		pr_err("incorrect value in jprobe handler\n");
-	}
-
-	jph_val = rand1;
-	jprobe_return();
-	return 0;
-}
-
-static struct jprobe jp = {
-	.entry		= j_kprobe_target,
-	.kp.symbol_name = "kprobe_target"
-};
-
-static int test_jprobe(void)
-{
-	int ret;
-
-	ret = register_jprobe(&jp);
-	if (ret < 0) {
-		pr_err("register_jprobe returned %d\n", ret);
-		return ret;
-	}
-
-	ret = target(rand1);
-	unregister_jprobe(&jp);
-	if (jph_val == 0) {
-		pr_err("jprobe handler not called\n");
-		handler_errors++;
-	}
-
-	return 0;
-}
-
-static struct jprobe jp2 = {
-	.entry          = j_kprobe_target,
-	.kp.symbol_name = "kprobe_target2"
-};
-
-static int test_jprobes(void)
-{
-	int ret;
-	struct jprobe *jps[2] = {&jp, &jp2};
-
-	/* addr and flags should be cleard for reusing kprobe. */
-	jp.kp.addr = NULL;
-	jp.kp.flags = 0;
-	ret = register_jprobes(jps, 2);
-	if (ret < 0) {
-		pr_err("register_jprobes returned %d\n", ret);
-		return ret;
-	}
-
-	jph_val = 0;
-	ret = target(rand1);
-	if (jph_val == 0) {
-		pr_err("jprobe handler not called\n");
-		handler_errors++;
-	}
-
-	jph_val = 0;
-	ret = target2(rand1);
-	if (jph_val == 0) {
-		pr_err("jprobe handler2 not called\n");
-		handler_errors++;
-	}
-	unregister_jprobes(jps, 2);
-
-	return 0;
-}
-#else
-#define test_jprobe() (0)
-#define test_jprobes() (0)
-#endif
 #ifdef CONFIG_KRETPROBES
 static u32 krph_val;
 
@@ -383,16 +299,6 @@ int init_test_probes(void)
 	if (ret < 0)
 		errors++;
 
-	num_tests++;
-	ret = test_jprobe();
-	if (ret < 0)
-		errors++;
-
-	num_tests++;
-	ret = test_jprobes();
-	if (ret < 0)
-		errors++;
-
 #ifdef CONFIG_KRETPROBES
 	num_tests++;
 	ret = test_kretprobe();

kernel/trace/trace_kprobe.c

@@ -1228,16 +1228,11 @@ kprobe_perf_func(struct trace_kprobe *tk, struct pt_regs *regs)
 
 		/*
 		 * We need to check and see if we modified the pc of the
-		 * pt_regs, and if so clear the kprobe and return 1 so that we
-		 * don't do the single stepping.
-		 * The ftrace kprobe handler leaves it up to us to re-enable
-		 * preemption here before returning if we've modified the ip.
+		 * pt_regs, and if so return 1 so that we don't do the
+		 * single stepping.
 		 */
-		if (orig_ip != instruction_pointer(regs)) {
-			reset_current_kprobe();
-			preempt_enable_no_resched();
+		if (orig_ip != instruction_pointer(regs))
 			return 1;
-		}
 		if (!ret)
 			return 0;
 	}

lib/Kconfig.debug

@@ -1718,7 +1718,7 @@ config KPROBES_SANITY_TEST
 	default n
 	help
 	  This option provides for testing basic kprobes functionality on
-	  boot. A sample kprobe, jprobe and kretprobe are inserted and
+	  boot. Samples of kprobe and kretprobe are inserted and
 	  verified for functionality.
 
 	  Say N if you are unsure.

tools/arch/arm64/include/uapi/asm/unistd.h

+/* SPDX-License-Identifier: GPL-2.0 WITH Linux-syscall-note */
+/*
+ * Copyright (C) 2012 ARM Ltd.
+ *
+ * This program is free software; you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License version 2 as
+ * published by the Free Software Foundation.
+ *
+ * This program is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+ * GNU General Public License for more details.
+ *
+ * You should have received a copy of the GNU General Public License
+ * along with this program.  If not, see <http://www.gnu.org/licenses/>.
+ */
+
+#define __ARCH_WANT_RENAMEAT
+
+#include <asm-generic/unistd.h>

tools/perf/Documentation/perf-list.txt

@@ -18,6 +18,10 @@ various perf commands with the -e option.
 
 OPTIONS
 -------
+-d::
+--desc::
+Print extra event descriptions. (default)
+
 --no-desc::
 Don't print descriptions.
 
@@ -25,11 +29,13 @@ Don't print descriptions.
 --long-desc::
 Print longer event descriptions.
 
+--debug::
+Enable debugging output.
+
 --details::
 Print how named events are resolved internally into perf events, and also
 any extra expressions computed by perf stat.
 
-
 [[EVENT_MODIFIERS]]
 EVENT MODIFIERS
 ---------------
@@ -234,7 +240,7 @@ perf also supports group leader sampling using the :S specifier.
   perf record -e '{cycles,instructions}:S' ...
   perf report --group
 
-Normally all events in a event group sample, but with :S only
+Normally all events in an event group sample, but with :S only
 the first event (the leader) samples, and it only reads the values of the
 other events in the group.
 

tools/perf/Documentation/perf-record.txt

@@ -94,7 +94,7 @@ OPTIONS
 	  "perf report" to view group events together.
 
 --filter=<filter>::
-        Event filter. This option should follow a event selector (-e) which
+        Event filter. This option should follow an event selector (-e) which
 	selects either tracepoint event(s) or a hardware trace PMU
 	(e.g. Intel PT or CoreSight).
 
@@ -153,7 +153,7 @@ OPTIONS
 
 --exclude-perf::
 	Don't record events issued by perf itself. This option should follow
-	a event selector (-e) which selects tracepoint event(s). It adds a
+	an event selector (-e) which selects tracepoint event(s). It adds a
 	filter expression 'common_pid != $PERFPID' to filters. If other
 	'--filter' exists, the new filter expression will be combined with
 	them by '&&'.

tools/perf/Makefile.config

@@ -54,6 +54,8 @@ endif
 
 ifeq ($(SRCARCH),arm64)
   NO_PERF_REGS := 0
+  NO_SYSCALL_TABLE := 0
+  CFLAGS += -I$(OUTPUT)arch/arm64/include/generated
   LIBUNWIND_LIBS = -lunwind -lunwind-aarch64
 endif
 
@@ -905,8 +907,8 @@ bindir = $(abspath $(prefix)/$(bindir_relative))
 mandir = share/man
 infodir = share/info
 perfexecdir = libexec/perf-core
-perf_include_dir = lib/include/perf
-perf_examples_dir = lib/examples/perf
+perf_include_dir = lib/perf/include
+perf_examples_dir = lib/perf/examples
 sharedir = $(prefix)/share
 template_dir = share/perf-core/templates
 STRACE_GROUPS_DIR = share/perf-core/strace/groups

tools/perf/Makefile.perf

@@ -384,6 +384,8 @@ export INSTALL SHELL_PATH
 
 SHELL = $(SHELL_PATH)
 
+linux_uapi_dir := $(srctree)/tools/include/uapi/linux
+
 beauty_outdir := $(OUTPUT)trace/beauty/generated
 beauty_ioctl_outdir := $(beauty_outdir)/ioctl
 drm_ioctl_array := $(beauty_ioctl_outdir)/drm_ioctl_array.c
@@ -431,6 +433,12 @@ kvm_ioctl_tbl := $(srctree)/tools/perf/trace/beauty/kvm_ioctl.sh
 $(kvm_ioctl_array): $(kvm_hdr_dir)/kvm.h $(kvm_ioctl_tbl)
 	$(Q)$(SHELL) '$(kvm_ioctl_tbl)' $(kvm_hdr_dir) > $@
 
+socket_ipproto_array := $(beauty_outdir)/socket_ipproto_array.c
+socket_ipproto_tbl := $(srctree)/tools/perf/trace/beauty/socket_ipproto.sh
+
+$(socket_ipproto_array): $(linux_uapi_dir)/in.h $(socket_ipproto_tbl)
+	$(Q)$(SHELL) '$(socket_ipproto_tbl)' $(linux_uapi_dir) > $@
+
 vhost_virtio_ioctl_array := $(beauty_ioctl_outdir)/vhost_virtio_ioctl_array.c
 vhost_virtio_hdr_dir := $(srctree)/tools/include/uapi/linux
 vhost_virtio_ioctl_tbl := $(srctree)/tools/perf/trace/beauty/vhost_virtio_ioctl.sh
@@ -566,6 +574,7 @@ prepare: $(OUTPUT)PERF-VERSION-FILE $(OUTPUT)common-cmds.h archheaders $(drm_ioc
 	$(sndrv_ctl_ioctl_array) \
 	$(kcmp_type_array) \
 	$(kvm_ioctl_array) \
+	$(socket_ipproto_array) \
 	$(vhost_virtio_ioctl_array) \
 	$(madvise_behavior_array) \
 	$(perf_ioctl_array) \
@@ -860,6 +869,7 @@ clean:: $(LIBTRACEEVENT)-clean $(LIBAPI)-clean $(LIBBPF)-clean $(LIBSUBCMD)-clea
 		$(OUTPUT)$(sndrv_pcm_ioctl_array) \
 		$(OUTPUT)$(kvm_ioctl_array) \
 		$(OUTPUT)$(kcmp_type_array) \
+		$(OUTPUT)$(socket_ipproto_array) \
 		$(OUTPUT)$(vhost_virtio_ioctl_array) \
 		$(OUTPUT)$(perf_ioctl_array) \
 		$(OUTPUT)$(prctl_option_array) \

tools/perf/arch/arm64/Makefile

@@ -4,3 +4,24 @@ PERF_HAVE_DWARF_REGS := 1
 endif
 PERF_HAVE_JITDUMP := 1
 PERF_HAVE_ARCH_REGS_QUERY_REGISTER_OFFSET := 1
+
+#
+# Syscall table generation for perf
+#
+
+out    := $(OUTPUT)arch/arm64/include/generated/asm
+header := $(out)/syscalls.c
+sysdef := $(srctree)/tools/include/uapi/asm-generic/unistd.h
+sysprf := $(srctree)/tools/perf/arch/arm64/entry/syscalls/
+systbl := $(sysprf)/mksyscalltbl
+
+# Create output directory if not already present
+_dummy := $(shell [ -d '$(out)' ] || mkdir -p '$(out)')
+
+$(header): $(sysdef) $(systbl)
+	$(Q)$(SHELL) '$(systbl)' '$(CC)' '$(HOSTCC)' $(sysdef) > $@
+
+clean::
+	$(call QUIET_CLEAN, arm64) $(RM) $(header)
+
+archheaders: $(header)

tools/perf/arch/arm64/entry/syscalls/mksyscalltbl

+#!/bin/sh
+# SPDX-License-Identifier: GPL-2.0
+#
+# Generate system call table for perf. Derived from
+# powerpc script.
+#
+# Copyright IBM Corp. 2017
+# Author(s):  Hendrik Brueckner <brueckner@linux.vnet.ibm.com>
+# Changed by: Ravi Bangoria <ravi.bangoria@linux.vnet.ibm.com>
+# Changed by: Kim Phillips <kim.phillips@arm.com>
+
+gcc=$1
+hostcc=$2
+input=$3
+
+if ! test -r $input; then
+	echo "Could not read input file" >&2
+	exit 1
+fi
+
+create_table_from_c()
+{
+	local sc nr last_sc
+
+	create_table_exe=`mktemp /tmp/create-table-XXXXXX`
+
+	{
+
+	cat <<-_EoHEADER
+		#include <stdio.h>
+		#define __ARCH_WANT_RENAMEAT
+		#include "$input"
+		int main(int argc, char *argv[])
+		{
+	_EoHEADER
+
+	while read sc nr; do
+		printf "%s\n" "	printf(\"\\t[%d] = \\\"$sc\\\",\\n\", __NR_$sc);"
+		last_sc=$sc
+	done
+
+	printf "%s\n" "	printf(\"#define SYSCALLTBL_ARM64_MAX_ID %d\\n\", __NR_$last_sc);"
+	printf "}\n"
+
+	} | $hostcc -o $create_table_exe -x c -
+
+	$create_table_exe
+
+	rm -f $create_table_exe
+}
+
+create_table()
+{
+	echo "static const char *syscalltbl_arm64[] = {"
+	create_table_from_c
+	echo "};"
+}
+
+$gcc -E -dM -x c  $input	       \
+	|sed -ne 's/^#define __NR_//p' \
+	|sort -t' ' -k2 -nu	       \
+	|create_table

tools/perf/arch/powerpc/util/skip-callchain-idx.c

@@ -58,9 +58,13 @@ static int check_return_reg(int ra_regno, Dwarf_Frame *frame)
 	}
 
 	/*
-	 * Check if return address is on the stack.
+	 * Check if return address is on the stack. If return address
+	 * is in a register (typically R0), it is yet to be saved on
+	 * the stack.
 	 */
-	if (nops != 0 || ops != NULL)
+	if ((nops != 0 || ops != NULL) &&
+		!(nops == 1 && ops[0].atom == DW_OP_regx &&
+			ops[0].number2 == 0 && ops[0].offset == 0))
 		return 0;
 
 	/*
@@ -246,7 +250,7 @@ int arch_skip_callchain_idx(struct thread *thread, struct ip_callchain *chain)
 	if (!chain || chain->nr < 3)
 		return skip_slot;
 
-	ip = chain->ips[2];
+	ip = chain->ips[1];
 
 	thread__find_symbol(thread, PERF_RECORD_MISC_USER, ip, &al);
 

tools/perf/arch/s390/util/kvm-stat.c

@@ -102,7 +102,7 @@ const char * const kvm_skip_events[] = {
 
 int cpu_isa_init(struct perf_kvm_stat *kvm, const char *cpuid)
 {
-	if (strstr(cpuid, "IBM/S390")) {
+	if (strstr(cpuid, "IBM")) {
 		kvm->exit_reasons = sie_exit_reasons;
 		kvm->exit_reasons_isa = "SIE";
 	} else

tools/perf/builtin-c2c.c

@@ -2193,7 +2193,7 @@ static void print_cacheline(struct c2c_hists *c2c_hists,
 	fprintf(out, "%s\n", bf);
 	fprintf(out, "  -------------------------------------------------------------\n");
 
-	hists__fprintf(&c2c_hists->hists, false, 0, 0, 0, out, true);
+	hists__fprintf(&c2c_hists->hists, false, 0, 0, 0, out, false);
 }
 
 static void print_pareto(FILE *out)
@@ -2268,7 +2268,7 @@ static void perf_c2c__hists_fprintf(FILE *out, struct perf_session *session)
 	fprintf(out, "=================================================\n");
 	fprintf(out, "#\n");
 
-	hists__fprintf(&c2c.hists.hists, true, 0, 0, 0, stdout, false);
+	hists__fprintf(&c2c.hists.hists, true, 0, 0, 0, stdout, true);
 
 	fprintf(out, "\n");
 	fprintf(out, "=================================================\n");
@@ -2349,6 +2349,9 @@ static int perf_c2c__browse_cacheline(struct hist_entry *he)
 	" s             Toggle full length of symbol and source line columns \n"
 	" q             Return back to cacheline list \n";
 
+	if (!he)
+		return 0;
+
 	/* Display compact version first. */
 	c2c.symbol_full = false;
 

tools/perf/builtin-diff.c

@@ -696,7 +696,7 @@ static void hists__process(struct hists *hists)
 	hists__output_resort(hists, NULL);
 
 	hists__fprintf(hists, !quiet, 0, 0, 0, stdout,
-		       symbol_conf.use_callchain);
+		       !symbol_conf.use_callchain);
 }
 
 static void data__fprintf(void)

tools/perf/builtin-top.c

@@ -307,7 +307,7 @@ static void perf_top__print_sym_table(struct perf_top *top)
 	hists__output_recalc_col_len(hists, top->print_entries - printed);
 	putchar('\n');
 	hists__fprintf(hists, false, top->print_entries - printed, win_width,
-		       top->min_percent, stdout, symbol_conf.use_callchain);
+		       top->min_percent, stdout, !symbol_conf.use_callchain);
 }
 
 static void prompt_integer(int *target, const char *msg)