!1021 [sync] PR-978: io_uring: fix the problem of running

Merge Pull Request from: @openeuler-sync-bot 
 

Origin pull request: 
https://gitee.com/openeuler/kernel/pulls/978 
 
PR sync from:  Li Lingfeng <lilingfeng3@huawei.com>
 https://mailweb.openeuler.org/hyperkitty/list/kernel@openeuler.org/thread/DP5GHDF7ULWL52W5DGYZWS6HBE5WJ52E/ 
patch1: arch: setup PF_IO_WORKER threads like PF_KTHREAD
  pre patch of patch4
patch2: arch: ensure parisc/powerpc handle PF_IO_WORKER in copy_thread()
  fix patch of patch1
patch3: kernel: don't call do_exit() for PF_IO_WORKER threads
  fix the segfault
patch4: x86/process: setup io_threads more like normal user space
threads
  allow io worker to exit

Jens Axboe (3):
  arch: setup PF_IO_WORKER threads like PF_KTHREAD
  arch: ensure parisc/powerpc handle PF_IO_WORKER in copy_thread()
  kernel: don't call do_exit() for PF_IO_WORKER threads

Stefan Metzmacher (1):
  x86/process: setup io_threads more like normal user space threads


-- 
2.31.1
 
 
Link:https://gitee.com/openeuler/kernel/pulls/1021 

Reviewed-by: Zucheng Zheng <zhengzucheng@huawei.com> 
Signed-off-by: Jialin Zhang <zhangjialin11@huawei.com> 

arch/alpha/kernel/process.c

@@ -249,7 +249,7 @@ int copy_thread(unsigned long clone_flags, unsigned long usp,
 	childti->pcb.ksp = (unsigned long) childstack;
 	childti->pcb.flags = 1;	/* set FEN, clear everything else */
 
-	if (unlikely(p->flags & PF_KTHREAD)) {
+	if (unlikely(p->flags & (PF_KTHREAD | PF_IO_WORKER))) {
 		/* kernel thread */
 		memset(childstack, 0,
 			sizeof(struct switch_stack) + sizeof(struct pt_regs));

arch/arc/kernel/process.c

@@ -191,7 +191,7 @@ int copy_thread(unsigned long clone_flags, unsigned long usp,
 	childksp[0] = 0;			/* fp */
 	childksp[1] = (unsigned long)ret_from_fork; /* blink */
 
-	if (unlikely(p->flags & PF_KTHREAD)) {
+	if (unlikely(p->flags & (PF_KTHREAD | PF_IO_WORKER))) {
 		memset(c_regs, 0, sizeof(struct pt_regs));
 
 		c_callee->r13 = kthread_arg;

arch/arm/kernel/process.c

@@ -243,7 +243,7 @@ int copy_thread(unsigned long clone_flags, unsigned long stack_start,
 	thread->cpu_domain = get_domain();
 #endif
 
-	if (likely(!(p->flags & PF_KTHREAD))) {
+	if (likely(!(p->flags & (PF_KTHREAD | PF_IO_WORKER)))) {
 		*childregs = *current_pt_regs();
 		childregs->ARM_r0 = 0;
 		if (stack_start)

arch/arm64/kernel/process.c

@@ -405,7 +405,7 @@ int copy_thread(unsigned long clone_flags, unsigned long stack_start,
 
 	ptrauth_thread_init_kernel(p);
 
-	if (likely(!(p->flags & PF_KTHREAD))) {
+	if (likely(!(p->flags & (PF_KTHREAD | PF_IO_WORKER)))) {
 		*childregs = *current_pt_regs();
 		childregs->regs[0] = 0;
 

arch/csky/kernel/process.c

@@ -49,7 +49,7 @@ int copy_thread(unsigned long clone_flags,
 	/* setup thread.sp for switch_to !!! */
 	p->thread.sp = (unsigned long)childstack;
 
-	if (unlikely(p->flags & PF_KTHREAD)) {
+	if (unlikely(p->flags & (PF_KTHREAD | PF_IO_WORKER))) {
 		memset(childregs, 0, sizeof(struct pt_regs));
 		childstack->r15 = (unsigned long) ret_from_kernel_thread;
 		childstack->r10 = kthread_arg;

arch/h8300/kernel/process.c

@@ -112,7 +112,7 @@ int copy_thread(unsigned long clone_flags, unsigned long usp,
 
 	childregs = (struct pt_regs *) (THREAD_SIZE + task_stack_page(p)) - 1;
 
-	if (unlikely(p->flags & PF_KTHREAD)) {
+	if (unlikely(p->flags & (PF_KTHREAD | PF_IO_WORKER))) {
 		memset(childregs, 0, sizeof(struct pt_regs));
 		childregs->retpc = (unsigned long) ret_from_kernel_thread;
 		childregs->er4 = topstk; /* arg */

arch/hexagon/kernel/process.c

@@ -73,7 +73,7 @@ int copy_thread(unsigned long clone_flags, unsigned long usp, unsigned long arg,
 						    sizeof(*ss));
 	ss->lr = (unsigned long)ret_from_fork;
 	p->thread.switch_sp = ss;
-	if (unlikely(p->flags & PF_KTHREAD)) {
+	if (unlikely(p->flags & (PF_KTHREAD | PF_IO_WORKER))) {
 		memset(childregs, 0, sizeof(struct pt_regs));
 		/* r24 <- fn, r25 <- arg */
 		ss->r24 = usp;

arch/ia64/kernel/process.c

@@ -337,7 +337,7 @@ copy_thread(unsigned long clone_flags, unsigned long user_stack_base,
 
 	ia64_drop_fpu(p);	/* don't pick up stale state from a CPU's fph */
 
-	if (unlikely(p->flags & PF_KTHREAD)) {
+	if (unlikely(p->flags & (PF_KTHREAD | PF_IO_WORKER))) {
 		if (unlikely(!user_stack_base)) {
 			/* fork_idle() called us */
 			return 0;

arch/m68k/kernel/process.c

@@ -157,7 +157,7 @@ int copy_thread(unsigned long clone_flags, unsigned long usp, unsigned long arg,
 	 */
 	p->thread.fs = get_fs().seg;
 
-	if (unlikely(p->flags & PF_KTHREAD)) {
+	if (unlikely(p->flags & (PF_KTHREAD | PF_IO_WORKER))) {
 		/* kernel thread */
 		memset(frame, 0, sizeof(struct fork_frame));
 		frame->regs.sr = PS_S;

arch/microblaze/kernel/process.c

@@ -59,7 +59,7 @@ int copy_thread(unsigned long clone_flags, unsigned long usp, unsigned long arg,
 	struct pt_regs *childregs = task_pt_regs(p);
 	struct thread_info *ti = task_thread_info(p);
 
-	if (unlikely(p->flags & PF_KTHREAD)) {
+	if (unlikely(p->flags & (PF_KTHREAD | PF_IO_WORKER))) {
 		/* if we're creating a new kernel thread then just zeroing all
 		 * the registers. That's OK for a brand new thread.*/
 		memset(childregs, 0, sizeof(struct pt_regs));

arch/mips/kernel/process.c

@@ -135,7 +135,7 @@ int copy_thread(unsigned long clone_flags, unsigned long usp,
 	/*  Put the stack after the struct pt_regs.  */
 	childksp = (unsigned long) childregs;
 	p->thread.cp0_status = (read_c0_status() & ~(ST0_CU2|ST0_CU1)) | ST0_KERNEL_CUMASK;
-	if (unlikely(p->flags & PF_KTHREAD)) {
+	if (unlikely(p->flags & (PF_KTHREAD | PF_IO_WORKER))) {
 		/* kernel thread */
 		unsigned long status = p->thread.cp0_status;
 		memset(childregs, 0, sizeof(struct pt_regs));

arch/nds32/kernel/process.c

@@ -156,7 +156,7 @@ int copy_thread(unsigned long clone_flags, unsigned long stack_start,
 
 	memset(&p->thread.cpu_context, 0, sizeof(struct cpu_context));
 
-	if (unlikely(p->flags & PF_KTHREAD)) {
+	if (unlikely(p->flags & (PF_KTHREAD | PF_IO_WORKER))) {
 		memset(childregs, 0, sizeof(struct pt_regs));
 		/* kernel thread fn */
 		p->thread.cpu_context.r6 = stack_start;

arch/nios2/kernel/process.c

@@ -109,7 +109,7 @@ int copy_thread(unsigned long clone_flags, unsigned long usp, unsigned long arg,
 	struct switch_stack *childstack =
 		((struct switch_stack *)childregs) - 1;
 
-	if (unlikely(p->flags & PF_KTHREAD)) {
+	if (unlikely(p->flags & (PF_KTHREAD | PF_IO_WORKER))) {
 		memset(childstack, 0,
 			sizeof(struct switch_stack) + sizeof(struct pt_regs));
 

arch/openrisc/kernel/process.c

@@ -167,7 +167,7 @@ copy_thread(unsigned long clone_flags, unsigned long usp, unsigned long arg,
 	sp -= sizeof(struct pt_regs);
 	kregs = (struct pt_regs *)sp;
 
-	if (unlikely(p->flags & PF_KTHREAD)) {
+	if (unlikely(p->flags & (PF_KTHREAD | PF_IO_WORKER))) {
 		memset(kregs, 0, sizeof(struct pt_regs));
 		kregs->gpr[20] = usp; /* fn, kernel thread */
 		kregs->gpr[22] = arg;

arch/parisc/kernel/process.c

@@ -200,7 +200,7 @@ copy_thread(unsigned long clone_flags, unsigned long usp,
 	extern void * const ret_from_kernel_thread;
 	extern void * const child_return;
 
-	if (unlikely(p->flags & PF_KTHREAD)) {
+	if (unlikely(p->flags & (PF_KTHREAD | PF_IO_WORKER))) {
 		/* kernel thread */
 		memset(cregs, 0, sizeof(struct pt_regs));
 		if (!usp) /* idle thread */

arch/powerpc/kernel/process.c

@@ -1684,7 +1684,7 @@ int copy_thread(unsigned long clone_flags, unsigned long usp,
 	/* Copy registers */
 	sp -= sizeof(struct pt_regs);
 	childregs = (struct pt_regs *) sp;
-	if (unlikely(p->flags & PF_KTHREAD)) {
+	if (unlikely(p->flags & (PF_KTHREAD | PF_IO_WORKER))) {
 		/* kernel thread */
 		memset(childregs, 0, sizeof(struct pt_regs));
 		childregs->gpr[1] = sp + sizeof(struct pt_regs);

arch/riscv/kernel/process.c

@@ -112,7 +112,7 @@ int copy_thread(unsigned long clone_flags, unsigned long usp, unsigned long arg,
 	struct pt_regs *childregs = task_pt_regs(p);
 
 	/* p->thread holds context to be restored by __switch_to() */
-	if (unlikely(p->flags & PF_KTHREAD)) {
+	if (unlikely(p->flags & (PF_KTHREAD | PF_IO_WORKER))) {
 		/* Kernel thread */
 		memset(childregs, 0, sizeof(struct pt_regs));
 		childregs->gp = gp_in_global;

arch/s390/kernel/process.c

@@ -127,7 +127,7 @@ int copy_thread(unsigned long clone_flags, unsigned long new_stackp,
 	frame->sf.gprs[9] = (unsigned long) frame;
 
 	/* Store access registers to kernel stack of new process. */
-	if (unlikely(p->flags & PF_KTHREAD)) {
+	if (unlikely(p->flags & (PF_KTHREAD | PF_IO_WORKER))) {
 		/* kernel thread */
 		memset(&frame->childregs, 0, sizeof(struct pt_regs));
 		frame->childregs.psw.mask = PSW_KERNEL_BITS | PSW_MASK_DAT |

arch/sh/kernel/process_32.c

@@ -114,7 +114,7 @@ int copy_thread(unsigned long clone_flags, unsigned long usp, unsigned long arg,
 
 	childregs = task_pt_regs(p);
 	p->thread.sp = (unsigned long) childregs;
-	if (unlikely(p->flags & PF_KTHREAD)) {
+	if (unlikely(p->flags & (PF_KTHREAD | PF_IO_WORKER))) {
 		memset(childregs, 0, sizeof(struct pt_regs));
 		p->thread.pc = (unsigned long) ret_from_kernel_thread;
 		childregs->regs[4] = arg;

arch/sparc/kernel/process_32.c

@@ -309,7 +309,7 @@ int copy_thread(unsigned long clone_flags, unsigned long sp, unsigned long arg,
 	ti->ksp = (unsigned long) new_stack;
 	p->thread.kregs = childregs;
 
-	if (unlikely(p->flags & PF_KTHREAD)) {
+	if (unlikely(p->flags & (PF_KTHREAD | PF_IO_WORKER))) {
 		extern int nwindows;
 		unsigned long psr;
 		memset(new_stack, 0, STACKFRAME_SZ + TRACEREG_SZ);

arch/sparc/kernel/process_64.c

@@ -599,7 +599,7 @@ int copy_thread(unsigned long clone_flags, unsigned long sp, unsigned long arg,
 				       sizeof(struct sparc_stackf));
 	t->fpsaved[0] = 0;
 
-	if (unlikely(p->flags & PF_KTHREAD)) {
+	if (unlikely(p->flags & (PF_KTHREAD | PF_IO_WORKER))) {
 		memset(child_trap_frame, 0, child_stack_sz);
 		__thread_flag_byte_ptr(t)[TI_FLAG_BYTE_CWP] = 
 			(current_pt_regs()->tstate + 1) & TSTATE_CWP;

arch/um/kernel/process.c

@@ -156,7 +156,7 @@ int copy_thread(unsigned long clone_flags, unsigned long sp,
 		unsigned long arg, struct task_struct * p, unsigned long tls)
 {
 	void (*handler)(void);
-	int kthread = current->flags & PF_KTHREAD;
+	int kthread = current->flags & (PF_KTHREAD | PF_IO_WORKER);
 	int ret = 0;
 
 	p->thread = (struct thread_struct) INIT_THREAD;

arch/x86/kernel/process.c

@@ -200,6 +200,23 @@ int copy_thread(unsigned long clone_flags, unsigned long sp, unsigned long arg,
 	task_user_gs(p) = get_user_gs(current_pt_regs());
 #endif
 
+	if (unlikely(p->flags & PF_IO_WORKER)) {
+		/*
+		 * An IO thread is a user space thread, but it doesn't
+		 * return to ret_after_fork().
+		 *
+		 * In order to indicate that to tools like gdb,
+		 * we reset the stack and instruction pointers.
+		 *
+		 * It does the same kernel frame setup to return to a kernel
+		 * function that a kernel thread does.
+		 */
+		childregs->sp = 0;
+		childregs->ip = 0;
+		kthread_frame_init(frame, sp, arg);
+		return 0;
+	}
+
 	/* Set a new TLS for the child thread? */
 	if (clone_flags & CLONE_SETTLS)
 		ret = set_new_tls(p, tls);

arch/xtensa/kernel/process.c

@@ -217,7 +217,7 @@ int copy_thread(unsigned long clone_flags, unsigned long usp_thread_fn,
 
 	p->thread.sp = (unsigned long)childregs;
 
-	if (!(p->flags & PF_KTHREAD)) {
+	if (!(p->flags & (PF_KTHREAD | PF_IO_WORKER))) {
 		struct pt_regs *regs = current_pt_regs();
 		unsigned long usp = usp_thread_fn ?
 			usp_thread_fn : regs->areg[1];

kernel/signal.c

@@ -2760,6 +2760,14 @@ bool get_signal(struct ksignal *ksig)
 			do_coredump(&ksig->info);
 		}
 
+		/*
+		 * PF_IO_WORKER threads will catch and exit on fatal signals
+		 * themselves. They have cleanup that must be performed, so
+		 * we cannot call do_exit() on their behalf.
+		 */
+		if (current->flags & PF_IO_WORKER)
+			goto out;
+
 		/*
 		 * Death signals, no core dump.
 		 */
@@ -2767,7 +2775,7 @@ bool get_signal(struct ksignal *ksig)
 		/* NOTREACHED */
 	}
 	spin_unlock_irq(&sighand->siglock);
-
+out:
 	ksig->sig = signr;
 	return ksig->sig > 0;
 }