arm: add support for TIF_NOTIFY_SIGNAL

stable inclusion
from stable-v5.10.162
commit 1bee9dbbcabbb77617fb257f964628b50ba2529c
category: bugfix
bugzilla: https://gitee.com/src-openeuler/kernel/issues/I6BTWC
CVE: NA

Reference: https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git/commit/?h=v5.10.168&id=1bee9dbbcabbb77617fb257f964628b50ba2529c

--------------------------------

[ Upstream commit 32d59773 ]

Wire up TIF_NOTIFY_SIGNAL handling for arm.

Cc: linux-arm-kernel@lists.infradead.org
Acked-by: NRussell King <rmk+kernel@armlinux.org.uk>
Signed-off-by: NJens Axboe <axboe@kernel.dk>

Conflicts:
	arch/arm/include/asm/thread_info.h
Signed-off-by: NLi Lingfeng <lilingfeng3@huawei.com>
Reviewed-by: Ntanghui <tanghui20@huawei.com>
Reviewed-by: NWang Weiyang <wangweiyang2@huawei.com>
Signed-off-by: NJialin Zhang <zhangjialin11@huawei.com>

arch/arm/include/asm/thread_info.h

@@ -137,6 +137,8 @@ extern int vfp_restore_user_hwstate(struct user_vfp *,
  * thread information flags:
  *  TIF_USEDFPU		- FPU was used by this task this quantum (SMP)
  *  TIF_POLLING_NRFLAG	- true if poll_idle() is polling TIF_NEED_RESCHED
+ *
+ * Any bit in the range of 0..15 will cause do_work_pending() to be invoked.
  */
 #define TIF_SIGPENDING		0	/* signal pending */
 #define TIF_NEED_RESCHED	1	/* rescheduling necessary */
@@ -147,6 +149,7 @@ extern int vfp_restore_user_hwstate(struct user_vfp *,
 #define TIF_SYSCALL_TRACEPOINT	6	/* syscall tracepoint instrumentation */
 #define TIF_SECCOMP		7	/* seccomp syscall filtering active */
 #define TIF_PATCH_PENDING	8	/* pending live patching update */
+#define TIF_NOTIFY_SIGNAL	9	/* signal notifications exist */
 
 #define TIF_USING_IWMMXT	17
 #define TIF_MEMDIE		18	/* is terminating due to OOM killer */
@@ -162,6 +165,7 @@ extern int vfp_restore_user_hwstate(struct user_vfp *,
 #define _TIF_SECCOMP		(1 << TIF_SECCOMP)
 #define _TIF_USING_IWMMXT	(1 << TIF_USING_IWMMXT)
 #define _TIF_PATCH_PENDING	(1 << TIF_PATCH_PENDING)
+#define _TIF_NOTIFY_SIGNAL	(1 << TIF_NOTIFY_SIGNAL)
 
 /* Checks for any syscall work in entry-common.S */
 #define _TIF_SYSCALL_WORK (_TIF_SYSCALL_TRACE | _TIF_SYSCALL_AUDIT | \
@@ -171,7 +175,8 @@ extern int vfp_restore_user_hwstate(struct user_vfp *,
  * Change these and you break ASM code in entry-common.S
  */
 #define _TIF_WORK_MASK		(_TIF_NEED_RESCHED | _TIF_SIGPENDING | \
-				 _TIF_NOTIFY_RESUME | _TIF_UPROBE)
+				 _TIF_NOTIFY_RESUME | _TIF_UPROBE | \
+				 _TIF_NOTIFY_SIGNAL)
 
 #endif /* __KERNEL__ */
 #endif /* __ASM_ARM_THREAD_INFO_H */

arch/arm/kernel/entry-common.S

@@ -54,7 +54,7 @@ __ret_fast_syscall:
 	cmp	r2, r1
 	blne	addr_limit_check_failed
 	ldr	r1, [tsk, #TI_FLAGS]		@ re-check for syscall tracing
-	tst	r1, #_TIF_SYSCALL_WORK | _TIF_WORK_MASK
+	movs	r1, r1, lsl #16
 	bne	fast_work_pending
 
 
@@ -92,7 +92,7 @@ __ret_fast_syscall:
 	cmp     r2, r1
 	blne	addr_limit_check_failed
 	ldr	r1, [tsk, #TI_FLAGS]		@ re-check for syscall tracing
-	tst	r1, #_TIF_SYSCALL_WORK | _TIF_WORK_MASK
+	movs	r1, r1, lsl #16
 	beq	no_work_pending
  UNWIND(.fnend		)
 ENDPROC(ret_fast_syscall)
@@ -134,7 +134,7 @@ ENTRY(ret_to_user_from_irq)
 	cmp	r2, r1
 	blne	addr_limit_check_failed
 	ldr	r1, [tsk, #TI_FLAGS]
-	tst	r1, #_TIF_WORK_MASK
+	movs	r1, r1, lsl #16
 	bne	slow_work_pending
 no_work_pending:
 	asm_trace_hardirqs_on save = 0

arch/arm/kernel/entry-v7m.S

@@ -59,7 +59,7 @@ __irq_entry:
 
 	get_thread_info tsk
 	ldr	r2, [tsk, #TI_FLAGS]
-	tst	r2, #_TIF_WORK_MASK
+	movs	r2, r2, lsl #16
 	beq	2f			@ no work pending
 	mov	r0, #V7M_SCB_ICSR_PENDSVSET
 	str	r0, [r1, V7M_SCB_ICSR]	@ raise PendSV

arch/arm/kernel/signal.c

@@ -655,7 +655,7 @@ do_work_pending(struct pt_regs *regs, unsigned int thread_flags, int syscall)
 			if (unlikely(!user_mode(regs)))
 				return 0;
 			local_irq_enable();
-			if (thread_flags & _TIF_SIGPENDING) {
+			if (thread_flags & (_TIF_SIGPENDING | _TIF_NOTIFY_SIGNAL)) {
 				int restart = do_signal(regs, syscall);
 				if (unlikely(restart)) {
 					/*