Merge branch 'x86-asm-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip

Pull x86 asm updates from Ingo Molnar:
 "The main changes in this cycle were:

   - vDSO and asm entry improvements (Andy Lutomirski)

   - Xen paravirt entry enhancements (Boris Ostrovsky)

   - asm entry labels enhancement (Borislav Petkov)

   - and other misc changes (Thomas Gleixner, me)"

* 'x86-asm-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip:
  x86/vsdo: Fix build on PARAVIRT_CLOCK=y, KVM_GUEST=n
  Revert "x86/kvm: On KVM re-enable (e.g. after suspend), update clocks"
  x86/entry/64_compat: Make labels local
  x86/platform/uv: Include clocksource.h for clocksource_touch_watchdog()
  x86/vdso: Enable vdso pvclock access on all vdso variants
  x86/vdso: Remove pvclock fixmap machinery
  x86/vdso: Get pvclock data from the vvar VMA instead of the fixmap
  x86, vdso, pvclock: Simplify and speed up the vdso pvclock reader
  x86/kvm: On KVM re-enable (e.g. after suspend), update clocks
  x86/entry/64: Bypass enter_from_user_mode on non-context-tracking boots
  x86/asm: Add asm macros for static keys/jump labels
  x86/asm: Error out if asm/jump_label.h is included inappropriately
  context_tracking: Switch to new static_branch API
  x86/entry, x86/paravirt: Remove the unused usergs_sysret32 PV op
  x86/paravirt: Remove the unused irq_enable_sysexit pv op
  x86/xen: Avoid fast syscall path for Xen PV guests

arch/x86/entry/calling.h

+#include <linux/jump_label.h>
+
 /*
 
  x86 function call convention, 64-bit:
@@ -232,3 +234,16 @@ For 32-bit we have the following conventions - kernel is built with
 
 #endif /* CONFIG_X86_64 */
 
+/*
+ * This does 'call enter_from_user_mode' unless we can avoid it based on
+ * kernel config or using the static jump infrastructure.
+ */
+.macro CALL_enter_from_user_mode
+#ifdef CONFIG_CONTEXT_TRACKING
+#ifdef HAVE_JUMP_LABEL
+	STATIC_JUMP_IF_FALSE .Lafter_call_\@, context_tracking_enabled, def=0
+#endif
+	call enter_from_user_mode
+.Lafter_call_\@:
+#endif
+.endm

arch/x86/entry/entry_32.S

@@ -329,7 +329,8 @@ sysenter_past_esp:
 	 * Return back to the vDSO, which will pop ecx and edx.
 	 * Don't bother with DS and ES (they already contain __USER_DS).
 	 */
-	ENABLE_INTERRUPTS_SYSEXIT
+	sti
+	sysexit
 
 .pushsection .fixup, "ax"
 2:	movl	$0, PT_FS(%esp)
@@ -552,11 +553,6 @@ ENTRY(native_iret)
 	iret
 	_ASM_EXTABLE(native_iret, iret_exc)
 END(native_iret)
-
-ENTRY(native_irq_enable_sysexit)
-	sti
-	sysexit
-END(native_irq_enable_sysexit)
 #endif
 
 ENTRY(overflow)

arch/x86/entry/entry_64.S

@@ -520,9 +520,7 @@ END(irq_entries_start)
 	 */
 	TRACE_IRQS_OFF
 
-#ifdef CONFIG_CONTEXT_TRACKING
-	call enter_from_user_mode
-#endif
+	CALL_enter_from_user_mode
 
 1:
 	/*
@@ -1066,9 +1064,7 @@ ENTRY(error_entry)
 	 * (which can take locks).
 	 */
 	TRACE_IRQS_OFF
-#ifdef CONFIG_CONTEXT_TRACKING
-	call enter_from_user_mode
-#endif
+	CALL_enter_from_user_mode
 	ret
 
 .Lerror_entry_done:

arch/x86/entry/entry_64_compat.S

@@ -18,13 +18,6 @@
 
 	.section .entry.text, "ax"
 
-#ifdef CONFIG_PARAVIRT
-ENTRY(native_usergs_sysret32)
-	swapgs
-	sysretl
-ENDPROC(native_usergs_sysret32)
-#endif
-
 /*
  * 32-bit SYSENTER instruction entry.
  *
@@ -103,15 +96,15 @@ ENTRY(entry_SYSENTER_compat)
 	 * This needs to happen before enabling interrupts so that
 	 * we don't get preempted with NT set.
 	 *
-	 * NB.: sysenter_fix_flags is a label with the code under it moved
+	 * NB.: .Lsysenter_fix_flags is a label with the code under it moved
 	 * out-of-line as an optimization: NT is unlikely to be set in the
 	 * majority of the cases and instead of polluting the I$ unnecessarily,
 	 * we're keeping that code behind a branch which will predict as
 	 * not-taken and therefore its instructions won't be fetched.
 	 */
 	testl	$X86_EFLAGS_NT, EFLAGS(%rsp)
-	jnz	sysenter_fix_flags
-sysenter_flags_fixed:
+	jnz	.Lsysenter_fix_flags
+.Lsysenter_flags_fixed:
 
 	/*
 	 * User mode is traced as though IRQs are on, and SYSENTER
@@ -126,10 +119,10 @@ sysenter_flags_fixed:
 		    "jmp .Lsyscall_32_done", X86_FEATURE_XENPV
 	jmp	sysret32_from_system_call
 
-sysenter_fix_flags:
+.Lsysenter_fix_flags:
 	pushq	$X86_EFLAGS_FIXED
 	popfq
-	jmp	sysenter_flags_fixed
+	jmp	.Lsysenter_flags_fixed
 ENDPROC(entry_SYSENTER_compat)
 
 /*
@@ -238,7 +231,8 @@ sysret32_from_system_call:
 	xorq	%r9, %r9
 	xorq	%r10, %r10
 	movq	RSP-ORIG_RAX(%rsp), %rsp
-        USERGS_SYSRET32
+	swapgs
+	sysretl
 END(entry_SYSCALL_compat)
 
 /*

arch/x86/entry/vdso/vclock_gettime.c

@@ -17,8 +17,10 @@
 #include <asm/vvar.h>
 #include <asm/unistd.h>
 #include <asm/msr.h>
+#include <asm/pvclock.h>
 #include <linux/math64.h>
 #include <linux/time.h>
+#include <linux/kernel.h>
 
 #define gtod (&VVAR(vsyscall_gtod_data))
 
@@ -36,12 +38,12 @@ static notrace cycle_t vread_hpet(void)
 }
 #endif
 
-#ifndef BUILD_VDSO32
+#ifdef CONFIG_PARAVIRT_CLOCK
+extern u8 pvclock_page
+	__attribute__((visibility("hidden")));
+#endif
 
-#include <linux/kernel.h>
-#include <asm/vsyscall.h>
-#include <asm/fixmap.h>
-#include <asm/pvclock.h>
+#ifndef BUILD_VDSO32
 
 notrace static long vdso_fallback_gettime(long clock, struct timespec *ts)
 {
@@ -60,75 +62,6 @@ notrace static long vdso_fallback_gtod(struct timeval *tv, struct timezone *tz)
 	return ret;
 }
 
-#ifdef CONFIG_PARAVIRT_CLOCK
-
-static notrace const struct pvclock_vsyscall_time_info *get_pvti(int cpu)
-{
-	const struct pvclock_vsyscall_time_info *pvti_base;
-	int idx = cpu / (PAGE_SIZE/PVTI_SIZE);
-	int offset = cpu % (PAGE_SIZE/PVTI_SIZE);
-
-	BUG_ON(PVCLOCK_FIXMAP_BEGIN + idx > PVCLOCK_FIXMAP_END);
-
-	pvti_base = (struct pvclock_vsyscall_time_info *)
-		    __fix_to_virt(PVCLOCK_FIXMAP_BEGIN+idx);
-
-	return &pvti_base[offset];
-}
-
-static notrace cycle_t vread_pvclock(int *mode)
-{
-	const struct pvclock_vsyscall_time_info *pvti;
-	cycle_t ret;
-	u64 last;
-	u32 version;
-	u8 flags;
-	unsigned cpu, cpu1;
-
-
-	/*
-	 * Note: hypervisor must guarantee that:
-	 * 1. cpu ID number maps 1:1 to per-CPU pvclock time info.
-	 * 2. that per-CPU pvclock time info is updated if the
-	 *    underlying CPU changes.
-	 * 3. that version is increased whenever underlying CPU
-	 *    changes.
-	 *
-	 */
-	do {
-		cpu = __getcpu() & VGETCPU_CPU_MASK;
-		/* TODO: We can put vcpu id into higher bits of pvti.version.
-		 * This will save a couple of cycles by getting rid of
-		 * __getcpu() calls (Gleb).
-		 */
-
-		pvti = get_pvti(cpu);
-
-		version = __pvclock_read_cycles(&pvti->pvti, &ret, &flags);
-
-		/*
-		 * Test we're still on the cpu as well as the version.
-		 * We could have been migrated just after the first
-		 * vgetcpu but before fetching the version, so we
-		 * wouldn't notice a version change.
-		 */
-		cpu1 = __getcpu() & VGETCPU_CPU_MASK;
-	} while (unlikely(cpu != cpu1 ||
-			  (pvti->pvti.version & 1) ||
-			  pvti->pvti.version != version));
-
-	if (unlikely(!(flags & PVCLOCK_TSC_STABLE_BIT)))
-		*mode = VCLOCK_NONE;
-
-	/* refer to tsc.c read_tsc() comment for rationale */
-	last = gtod->cycle_last;
-
-	if (likely(ret >= last))
-		return ret;
-
-	return last;
-}
-#endif
 
 #else
 
@@ -162,15 +95,77 @@ notrace static long vdso_fallback_gtod(struct timeval *tv, struct timezone *tz)
 	return ret;
 }
 
+#endif
+
 #ifdef CONFIG_PARAVIRT_CLOCK
+static notrace const struct pvclock_vsyscall_time_info *get_pvti0(void)
+{
+	return (const struct pvclock_vsyscall_time_info *)&pvclock_page;
+}
 
 static notrace cycle_t vread_pvclock(int *mode)
 {
+	const struct pvclock_vcpu_time_info *pvti = &get_pvti0()->pvti;
+	cycle_t ret;
+	u64 tsc, pvti_tsc;
+	u64 last, delta, pvti_system_time;
+	u32 version, pvti_tsc_to_system_mul, pvti_tsc_shift;
+
+	/*
+	 * Note: The kernel and hypervisor must guarantee that cpu ID
+	 * number maps 1:1 to per-CPU pvclock time info.
+	 *
+	 * Because the hypervisor is entirely unaware of guest userspace
+	 * preemption, it cannot guarantee that per-CPU pvclock time
+	 * info is updated if the underlying CPU changes or that that
+	 * version is increased whenever underlying CPU changes.
+	 *
+	 * On KVM, we are guaranteed that pvti updates for any vCPU are
+	 * atomic as seen by *all* vCPUs.  This is an even stronger
+	 * guarantee than we get with a normal seqlock.
+	 *
+	 * On Xen, we don't appear to have that guarantee, but Xen still
+	 * supplies a valid seqlock using the version field.
+
+	 * We only do pvclock vdso timing at all if
+	 * PVCLOCK_TSC_STABLE_BIT is set, and we interpret that bit to
+	 * mean that all vCPUs have matching pvti and that the TSC is
+	 * synced, so we can just look at vCPU 0's pvti.
+	 */
+
+	if (unlikely(!(pvti->flags & PVCLOCK_TSC_STABLE_BIT))) {
 		*mode = VCLOCK_NONE;
 		return 0;
-}
-#endif
+	}
+
+	do {
+		version = pvti->version;
+
+		smp_rmb();
+
+		tsc = rdtsc_ordered();
+		pvti_tsc_to_system_mul = pvti->tsc_to_system_mul;
+		pvti_tsc_shift = pvti->tsc_shift;
+		pvti_system_time = pvti->system_time;
+		pvti_tsc = pvti->tsc_timestamp;
 
+		/* Make sure that the version double-check is last. */
+		smp_rmb();
+	} while (unlikely((version & 1) || version != pvti->version));
+
+	delta = tsc - pvti_tsc;
+	ret = pvti_system_time +
+		pvclock_scale_delta(delta, pvti_tsc_to_system_mul,
+				    pvti_tsc_shift);
+
+	/* refer to vread_tsc() comment for rationale */
+	last = gtod->cycle_last;
+
+	if (likely(ret >= last))
+		return ret;
+
+	return last;
+}
 #endif
 
 notrace static cycle_t vread_tsc(void)

arch/x86/entry/vdso/vdso-layout.lds.S

@@ -25,7 +25,7 @@ SECTIONS
 	 * segment.
 	 */
 
-	vvar_start = . - 2 * PAGE_SIZE;
+	vvar_start = . - 3 * PAGE_SIZE;
 	vvar_page = vvar_start;
 
 	/* Place all vvars at the offsets in asm/vvar.h. */
@@ -36,6 +36,7 @@ SECTIONS
 #undef EMIT_VVAR
 
 	hpet_page = vvar_start + PAGE_SIZE;
+	pvclock_page = vvar_start + 2 * PAGE_SIZE;
 
 	. = SIZEOF_HEADERS;
 

arch/x86/entry/vdso/vdso2c.c

@@ -73,6 +73,7 @@ enum {
 	sym_vvar_start,
 	sym_vvar_page,
 	sym_hpet_page,
+	sym_pvclock_page,
 	sym_VDSO_FAKE_SECTION_TABLE_START,
 	sym_VDSO_FAKE_SECTION_TABLE_END,
 };
@@ -80,6 +81,7 @@ enum {
 const int special_pages[] = {
 	sym_vvar_page,
 	sym_hpet_page,
+	sym_pvclock_page,
 };
 
 struct vdso_sym {
@@ -91,6 +93,7 @@ struct vdso_sym required_syms[] = {
 	[sym_vvar_start] = {"vvar_start", true},
 	[sym_vvar_page] = {"vvar_page", true},
 	[sym_hpet_page] = {"hpet_page", true},
+	[sym_pvclock_page] = {"pvclock_page", true},
 	[sym_VDSO_FAKE_SECTION_TABLE_START] = {
 		"VDSO_FAKE_SECTION_TABLE_START", false
 	},

arch/x86/entry/vdso/vma.c

@@ -12,6 +12,7 @@
 #include <linux/random.h>
 #include <linux/elf.h>
 #include <linux/cpu.h>
+#include <asm/pvclock.h>
 #include <asm/vgtod.h>
 #include <asm/proto.h>
 #include <asm/vdso.h>
@@ -100,6 +101,7 @@ static int map_vdso(const struct vdso_image *image, bool calculate_addr)
 		.name = "[vvar]",
 		.pages = no_pages,
 	};
+	struct pvclock_vsyscall_time_info *pvti;
 
 	if (calculate_addr) {
 		addr = vdso_addr(current->mm->start_stack,
@@ -169,6 +171,18 @@ static int map_vdso(const struct vdso_image *image, bool calculate_addr)
 	}
 #endif
 
+	pvti = pvclock_pvti_cpu0_va();
+	if (pvti && image->sym_pvclock_page) {
+		ret = remap_pfn_range(vma,
+				      text_start + image->sym_pvclock_page,
+				      __pa(pvti) >> PAGE_SHIFT,
+				      PAGE_SIZE,
+				      PAGE_READONLY);
+
+		if (ret)
+			goto up_fail;
+	}
+
 up_fail:
 	if (ret)
 		current->mm->context.vdso = NULL;

arch/x86/include/asm/fixmap.h

@@ -19,7 +19,6 @@
 #include <asm/acpi.h>
 #include <asm/apicdef.h>
 #include <asm/page.h>
-#include <asm/pvclock.h>
 #ifdef CONFIG_X86_32
 #include <linux/threads.h>
 #include <asm/kmap_types.h>
@@ -72,10 +71,6 @@ enum fixed_addresses {
 #ifdef CONFIG_X86_VSYSCALL_EMULATION
 	VSYSCALL_PAGE = (FIXADDR_TOP - VSYSCALL_ADDR) >> PAGE_SHIFT,
 #endif
-#ifdef CONFIG_PARAVIRT_CLOCK
-	PVCLOCK_FIXMAP_BEGIN,
-	PVCLOCK_FIXMAP_END = PVCLOCK_FIXMAP_BEGIN+PVCLOCK_VSYSCALL_NR_PAGES-1,
-#endif
 #endif
 	FIX_DBGP_BASE,
 	FIX_EARLYCON_MEM_BASE,

arch/x86/include/asm/jump_label.h

 #ifndef _ASM_X86_JUMP_LABEL_H
 #define _ASM_X86_JUMP_LABEL_H
 
-#ifndef __ASSEMBLY__
-
-#include <linux/stringify.h>
-#include <linux/types.h>
-#include <asm/nops.h>
-#include <asm/asm.h>
+#ifndef HAVE_JUMP_LABEL
+/*
+ * For better or for worse, if jump labels (the gcc extension) are missing,
+ * then the entire static branch patching infrastructure is compiled out.
+ * If that happens, the code in here will malfunction.  Raise a compiler
+ * error instead.
+ *
+ * In theory, jump labels and the static branch patching infrastructure
+ * could be decoupled to fix this.
+ */
+#error asm/jump_label.h included on a non-jump-label kernel
+#endif
 
 #define JUMP_LABEL_NOP_SIZE 5
 
@@ -16,6 +22,14 @@
 # define STATIC_KEY_INIT_NOP GENERIC_NOP5_ATOMIC
 #endif
 
+#include <asm/asm.h>
+#include <asm/nops.h>
+
+#ifndef __ASSEMBLY__
+
+#include <linux/stringify.h>
+#include <linux/types.h>
+
 static __always_inline bool arch_static_branch(struct static_key *key, bool branch)
 {
 	asm_volatile_goto("1:"
@@ -59,5 +73,40 @@ struct jump_entry {
 	jump_label_t key;
 };
 
+#else	/* __ASSEMBLY__ */
+
+.macro STATIC_JUMP_IF_TRUE target, key, def
+.Lstatic_jump_\@:
+	.if \def
+	/* Equivalent to "jmp.d32 \target" */
+	.byte		0xe9
+	.long		\target - .Lstatic_jump_after_\@
+.Lstatic_jump_after_\@:
+	.else
+	.byte		STATIC_KEY_INIT_NOP
+	.endif
+	.pushsection __jump_table, "aw"
+	_ASM_ALIGN
+	_ASM_PTR	.Lstatic_jump_\@, \target, \key
+	.popsection
+.endm
+
+.macro STATIC_JUMP_IF_FALSE target, key, def
+.Lstatic_jump_\@:
+	.if \def
+	.byte		STATIC_KEY_INIT_NOP
+	.else
+	/* Equivalent to "jmp.d32 \target" */
+	.byte		0xe9
+	.long		\target - .Lstatic_jump_after_\@
+.Lstatic_jump_after_\@:
+	.endif
+	.pushsection __jump_table, "aw"
+	_ASM_ALIGN
+	_ASM_PTR	.Lstatic_jump_\@, \target, \key + 1
+	.popsection
+.endm
+
 #endif	/* __ASSEMBLY__ */
+
 #endif

arch/x86/include/asm/paravirt.h

@@ -928,23 +928,11 @@ extern void default_banner(void);
 		  call PARA_INDIRECT(pv_irq_ops+PV_IRQ_irq_enable);	\
 		  PV_RESTORE_REGS(clobbers | CLBR_CALLEE_SAVE);)
 
-#define USERGS_SYSRET32							\
-	PARA_SITE(PARA_PATCH(pv_cpu_ops, PV_CPU_usergs_sysret32),	\
-		  CLBR_NONE,						\
-		  jmp PARA_INDIRECT(pv_cpu_ops+PV_CPU_usergs_sysret32))
-
 #ifdef CONFIG_X86_32
 #define GET_CR0_INTO_EAX				\
 	push %ecx; push %edx;				\
 	call PARA_INDIRECT(pv_cpu_ops+PV_CPU_read_cr0);	\
 	pop %edx; pop %ecx
-
-#define ENABLE_INTERRUPTS_SYSEXIT					\
-	PARA_SITE(PARA_PATCH(pv_cpu_ops, PV_CPU_irq_enable_sysexit),	\
-		  CLBR_NONE,						\
-		  jmp PARA_INDIRECT(pv_cpu_ops+PV_CPU_irq_enable_sysexit))
-
-
 #else	/* !CONFIG_X86_32 */
 
 /*

arch/x86/include/asm/paravirt_types.h

@@ -162,15 +162,6 @@ struct pv_cpu_ops {
 
 	u64 (*read_pmc)(int counter);
 
-#ifdef CONFIG_X86_32
-	/*
-	 * Atomically enable interrupts and return to userspace.  This
-	 * is only used in 32-bit kernels.  64-bit kernels use
-	 * usergs_sysret32 instead.
-	 */
-	void (*irq_enable_sysexit)(void);
-#endif
-
 	/*
 	 * Switch to usermode gs and return to 64-bit usermode using
 	 * sysret.  Only used in 64-bit kernels to return to 64-bit
@@ -179,14 +170,6 @@ struct pv_cpu_ops {
 	 */
 	void (*usergs_sysret64)(void);
 
-	/*
-	 * Switch to usermode gs and return to 32-bit usermode using
-	 * sysret.  Used to return to 32-on-64 compat processes.
-	 * Other usermode register state, including %esp, must already
-	 * be restored.
-	 */
-	void (*usergs_sysret32)(void);
-
 	/* Normal iret.  Jump to this with the standard iret stack
 	   frame set up. */
 	void (*iret)(void);

arch/x86/include/asm/pvclock.h

@@ -4,6 +4,15 @@
 #include <linux/clocksource.h>
 #include <asm/pvclock-abi.h>
 
+#ifdef CONFIG_KVM_GUEST
+extern struct pvclock_vsyscall_time_info *pvclock_pvti_cpu0_va(void);
+#else
+static inline struct pvclock_vsyscall_time_info *pvclock_pvti_cpu0_va(void)
+{
+	return NULL;
+}
+#endif
+
 /* some helper functions for xen and kvm pv clock sources */
 cycle_t pvclock_clocksource_read(struct pvclock_vcpu_time_info *src);
 u8 pvclock_read_flags(struct pvclock_vcpu_time_info *src);
@@ -91,10 +100,5 @@ struct pvclock_vsyscall_time_info {
 } __attribute__((__aligned__(SMP_CACHE_BYTES)));
 
 #define PVTI_SIZE sizeof(struct pvclock_vsyscall_time_info)
-#define PVCLOCK_VSYSCALL_NR_PAGES (((NR_CPUS-1)/(PAGE_SIZE/PVTI_SIZE))+1)
-
-int __init pvclock_init_vsyscall(struct pvclock_vsyscall_time_info *i,
-				 int size);
-struct pvclock_vcpu_time_info *pvclock_get_vsyscall_time_info(int cpu);
 
 #endif /* _ASM_X86_PVCLOCK_H */

arch/x86/include/asm/vdso.h

@@ -22,6 +22,7 @@ struct vdso_image {
 
 	long sym_vvar_page;
 	long sym_hpet_page;
+	long sym_pvclock_page;
 	long sym_VDSO32_NOTE_MASK;
 	long sym___kernel_sigreturn;
 	long sym___kernel_rt_sigreturn;

arch/x86/kernel/asm-offsets.c

@@ -65,9 +65,6 @@ void common(void) {
 	OFFSET(PV_IRQ_irq_disable, pv_irq_ops, irq_disable);
 	OFFSET(PV_IRQ_irq_enable, pv_irq_ops, irq_enable);
 	OFFSET(PV_CPU_iret, pv_cpu_ops, iret);
-#ifdef CONFIG_X86_32
-	OFFSET(PV_CPU_irq_enable_sysexit, pv_cpu_ops, irq_enable_sysexit);
-#endif
 	OFFSET(PV_CPU_read_cr0, pv_cpu_ops, read_cr0);
 	OFFSET(PV_MMU_read_cr2, pv_mmu_ops, read_cr2);
 #endif

arch/x86/kernel/asm-offsets_64.c

@@ -23,7 +23,6 @@ int main(void)
 {
 #ifdef CONFIG_PARAVIRT
 	OFFSET(PV_IRQ_adjust_exception_frame, pv_irq_ops, adjust_exception_frame);
-	OFFSET(PV_CPU_usergs_sysret32, pv_cpu_ops, usergs_sysret32);
 	OFFSET(PV_CPU_usergs_sysret64, pv_cpu_ops, usergs_sysret64);
 	OFFSET(PV_CPU_swapgs, pv_cpu_ops, swapgs);
 	BLANK();

arch/x86/kernel/kvmclock.c

@@ -45,6 +45,11 @@ early_param("no-kvmclock", parse_no_kvmclock);
 static struct pvclock_vsyscall_time_info *hv_clock;
 static struct pvclock_wall_clock wall_clock;
 
+struct pvclock_vsyscall_time_info *pvclock_pvti_cpu0_va(void)
+{
+	return hv_clock;
+}
+
 /*
  * The wallclock is the time of day when we booted. Since then, some time may
  * have elapsed since the hypervisor wrote the data. So we try to account for
@@ -305,7 +310,6 @@ int __init kvm_setup_vsyscall_timeinfo(void)
 {
 #ifdef CONFIG_X86_64
 	int cpu;
-	int ret;
 	u8 flags;
 	struct pvclock_vcpu_time_info *vcpu_time;
 	unsigned int size;
@@ -325,11 +329,6 @@ int __init kvm_setup_vsyscall_timeinfo(void)
 		return 1;
 	}
 
-	if ((ret = pvclock_init_vsyscall(hv_clock, size))) {
-		put_cpu();
-		return ret;
-	}
-
 	put_cpu();
 
 	kvm_clock.archdata.vclock_mode = VCLOCK_PVCLOCK;

arch/x86/kernel/paravirt.c

@@ -162,10 +162,6 @@ unsigned paravirt_patch_default(u8 type, u16 clobbers, void *insnbuf,
 		ret = paravirt_patch_ident_64(insnbuf, len);
 
 	else if (type == PARAVIRT_PATCH(pv_cpu_ops.iret) ||
-#ifdef CONFIG_X86_32
-		 type == PARAVIRT_PATCH(pv_cpu_ops.irq_enable_sysexit) ||
-#endif
-		 type == PARAVIRT_PATCH(pv_cpu_ops.usergs_sysret32) ||
 		 type == PARAVIRT_PATCH(pv_cpu_ops.usergs_sysret64))
 		/* If operation requires a jmp, then jmp */
 		ret = paravirt_patch_jmp(insnbuf, opfunc, addr, len);
@@ -220,8 +216,6 @@ static u64 native_steal_clock(int cpu)
 
 /* These are in entry.S */
 extern void native_iret(void);
-extern void native_irq_enable_sysexit(void);
-extern void native_usergs_sysret32(void);
 extern void native_usergs_sysret64(void);
 
 static struct resource reserve_ioports = {
@@ -379,13 +373,7 @@ __visible struct pv_cpu_ops pv_cpu_ops = {
 
 	.load_sp0 = native_load_sp0,
 
-#if defined(CONFIG_X86_32)
-	.irq_enable_sysexit = native_irq_enable_sysexit,
-#endif
 #ifdef CONFIG_X86_64
-#ifdef CONFIG_IA32_EMULATION
-	.usergs_sysret32 = native_usergs_sysret32,
-#endif
 	.usergs_sysret64 = native_usergs_sysret64,
 #endif
 	.iret = native_iret,

arch/x86/kernel/paravirt_patch_32.c

@@ -5,7 +5,6 @@ DEF_NATIVE(pv_irq_ops, irq_enable, "sti");
 DEF_NATIVE(pv_irq_ops, restore_fl, "push %eax; popf");
 DEF_NATIVE(pv_irq_ops, save_fl, "pushf; pop %eax");
 DEF_NATIVE(pv_cpu_ops, iret, "iret");
-DEF_NATIVE(pv_cpu_ops, irq_enable_sysexit, "sti; sysexit");
 DEF_NATIVE(pv_mmu_ops, read_cr2, "mov %cr2, %eax");
 DEF_NATIVE(pv_mmu_ops, write_cr3, "mov %eax, %cr3");
 DEF_NATIVE(pv_mmu_ops, read_cr3, "mov %cr3, %eax");
@@ -46,7 +45,6 @@ unsigned native_patch(u8 type, u16 clobbers, void *ibuf,
 		PATCH_SITE(pv_irq_ops, restore_fl);
 		PATCH_SITE(pv_irq_ops, save_fl);
 		PATCH_SITE(pv_cpu_ops, iret);
-		PATCH_SITE(pv_cpu_ops, irq_enable_sysexit);
 		PATCH_SITE(pv_mmu_ops, read_cr2);
 		PATCH_SITE(pv_mmu_ops, read_cr3);
 		PATCH_SITE(pv_mmu_ops, write_cr3);

arch/x86/kernel/paravirt_patch_64.c

@@ -13,9 +13,7 @@ DEF_NATIVE(pv_mmu_ops, flush_tlb_single, "invlpg (%rdi)");
 DEF_NATIVE(pv_cpu_ops, clts, "clts");
 DEF_NATIVE(pv_cpu_ops, wbinvd, "wbinvd");
 
-DEF_NATIVE(pv_cpu_ops, irq_enable_sysexit, "swapgs; sti; sysexit");
 DEF_NATIVE(pv_cpu_ops, usergs_sysret64, "swapgs; sysretq");
-DEF_NATIVE(pv_cpu_ops, usergs_sysret32, "swapgs; sysretl");
 DEF_NATIVE(pv_cpu_ops, swapgs, "swapgs");
 
 DEF_NATIVE(, mov32, "mov %edi, %eax");
@@ -55,7 +53,6 @@ unsigned native_patch(u8 type, u16 clobbers, void *ibuf,
 		PATCH_SITE(pv_irq_ops, save_fl);
 		PATCH_SITE(pv_irq_ops, irq_enable);
 		PATCH_SITE(pv_irq_ops, irq_disable);
-		PATCH_SITE(pv_cpu_ops, usergs_sysret32);
 		PATCH_SITE(pv_cpu_ops, usergs_sysret64);
 		PATCH_SITE(pv_cpu_ops, swapgs);
 		PATCH_SITE(pv_mmu_ops, read_cr2);

arch/x86/kernel/pvclock.c

@@ -140,27 +140,3 @@ void pvclock_read_wallclock(struct pvclock_wall_clock *wall_clock,
 
 	set_normalized_timespec(ts, now.tv_sec, now.tv_nsec);
 }
-
-#ifdef CONFIG_X86_64
-/*
- * Initialize the generic pvclock vsyscall state.  This will allocate
- * a/some page(s) for the per-vcpu pvclock information, set up a
- * fixmap mapping for the page(s)
- */
-
-int __init pvclock_init_vsyscall(struct pvclock_vsyscall_time_info *i,
-				 int size)
-{
-	int idx;
-
-	WARN_ON (size != PVCLOCK_VSYSCALL_NR_PAGES*PAGE_SIZE);
-
-	for (idx = 0; idx <= (PVCLOCK_FIXMAP_END-PVCLOCK_FIXMAP_BEGIN); idx++) {
-		__set_fixmap(PVCLOCK_FIXMAP_BEGIN + idx,
-			     __pa(i) + (idx*PAGE_SIZE),
-			     PAGE_KERNEL_VVAR);
-	}
-
-	return 0;
-}
-#endif

arch/x86/platform/uv/uv_nmi.c

@@ -28,6 +28,7 @@
 #include <linux/nmi.h>
 #include <linux/sched.h>
 #include <linux/slab.h>
+#include <linux/clocksource.h>
 
 #include <asm/apic.h>
 #include <asm/current.h>

arch/x86/xen/enlighten.c

@@ -1229,10 +1229,7 @@ static const struct pv_cpu_ops xen_cpu_ops __initconst = {
 
 	.iret = xen_iret,
 #ifdef CONFIG_X86_64
-	.usergs_sysret32 = xen_sysret32,
 	.usergs_sysret64 = xen_sysret64,
-#else
-	.irq_enable_sysexit = xen_sysexit,
 #endif
 
 	.load_tr_desc = paravirt_nop,

arch/x86/xen/xen-asm_32.S

@@ -34,20 +34,6 @@ check_events:
 	pop %eax
 	ret
 
-/*
- * We can't use sysexit directly, because we're not running in ring0.
- * But we can easily fake it up using iret.  Assuming xen_sysexit is
- * jumped to with a standard stack frame, we can just strip it back to
- * a standard iret frame and use iret.
- */
-ENTRY(xen_sysexit)
-	movl PT_EAX(%esp), %eax			/* Shouldn't be necessary? */
-	orl $X86_EFLAGS_IF, PT_EFLAGS(%esp)
-	lea PT_EIP(%esp), %esp
-
-	jmp xen_iret
-ENDPROC(xen_sysexit)
-
 /*
  * This is run where a normal iret would be run, with the same stack setup:
  *	8: eflags

arch/x86/xen/xen-asm_64.S

@@ -68,25 +68,6 @@ ENTRY(xen_sysret64)
 ENDPATCH(xen_sysret64)
 RELOC(xen_sysret64, 1b+1)
 
-ENTRY(xen_sysret32)
-	/*
-	 * We're already on the usermode stack at this point, but
-	 * still with the kernel gs, so we can easily switch back
-	 */
-	movq %rsp, PER_CPU_VAR(rsp_scratch)
-	movq PER_CPU_VAR(cpu_current_top_of_stack), %rsp
-
-	pushq $__USER32_DS
-	pushq PER_CPU_VAR(rsp_scratch)
-	pushq %r11
-	pushq $__USER32_CS
-	pushq %rcx
-
-	pushq $0
-1:	jmp hypercall_iret
-ENDPATCH(xen_sysret32)
-RELOC(xen_sysret32, 1b+1)
-
 /*
  * Xen handles syscall callbacks much like ordinary exceptions, which
  * means we have:

arch/x86/xen/xen-ops.h

@@ -139,9 +139,6 @@ DECL_ASM(void, xen_restore_fl_direct, unsigned long);
 
 /* These are not functions, and cannot be called normally */
 __visible void xen_iret(void);
-#ifdef CONFIG_X86_32
-__visible void xen_sysexit(void);
-#endif
 __visible void xen_sysret32(void);
 __visible void xen_sysret64(void);
 __visible void xen_adjust_exception_frame(void);

include/linux/context_tracking_state.h

@@ -22,12 +22,12 @@ struct context_tracking {
 };
 
 #ifdef CONFIG_CONTEXT_TRACKING
-extern struct static_key context_tracking_enabled;
+extern struct static_key_false context_tracking_enabled;
 DECLARE_PER_CPU(struct context_tracking, context_tracking);
 
 static inline bool context_tracking_is_enabled(void)
 {
-	return static_key_false(&context_tracking_enabled);
+	return static_branch_unlikely(&context_tracking_enabled);
 }
 
 static inline bool context_tracking_cpu_is_enabled(void)

kernel/context_tracking.c

@@ -24,7 +24,7 @@
 #define CREATE_TRACE_POINTS
 #include <trace/events/context_tracking.h>
 
-struct static_key context_tracking_enabled = STATIC_KEY_INIT_FALSE;
+DEFINE_STATIC_KEY_FALSE(context_tracking_enabled);
 EXPORT_SYMBOL_GPL(context_tracking_enabled);
 
 DEFINE_PER_CPU(struct context_tracking, context_tracking);
@@ -191,7 +191,7 @@ void __init context_tracking_cpu_set(int cpu)
 
 	if (!per_cpu(context_tracking.active, cpu)) {
 		per_cpu(context_tracking.active, cpu) = true;
-		static_key_slow_inc(&context_tracking_enabled);
+		static_branch_inc(&context_tracking_enabled);
 	}
 
 	if (initialized)