From bec58f40d6c5372d812c93cc3947f3bc97440e57 Mon Sep 17 00:00:00 2001
From: Jens Axboe <axboe@kernel.dk>
Date: Fri, 9 Oct 2020 15:56:07 -0600
Subject: [PATCH] xtensa: add support for TIF_NOTIFY_SIGNAL

Wire up TIF_NOTIFY_SIGNAL handling for xtensa.

Thanks to Max Filippov <jcmvbkbc@gmail.com> for making the asm correct.

Cc: linux-xtensa@linux-xtensa.org
Signed-off-by: Jens Axboe <axboe@kernel.dk>
---
 arch/xtensa/include/asm/thread_info.h | 5 ++++-
 arch/xtensa/kernel/entry.S            | 4 ++--
 arch/xtensa/kernel/signal.c           | 3 ++-
 3 files changed, 8 insertions(+), 4 deletions(-)

diff --git a/arch/xtensa/include/asm/thread_info.h b/arch/xtensa/include/asm/thread_info.h
index 6acbbe0d87d3..a312333a9add 100644
--- a/arch/xtensa/include/asm/thread_info.h
+++ b/arch/xtensa/include/asm/thread_info.h
@@ -111,18 +111,21 @@ static inline struct thread_info *current_thread_info(void)
 #define TIF_NEED_RESCHED	2	/* rescheduling necessary */
 #define TIF_SINGLESTEP		3	/* restore singlestep on return to user mode */
 #define TIF_SYSCALL_TRACEPOINT	4	/* syscall tracepoint instrumentation */
-#define TIF_MEMDIE		5	/* is terminating due to OOM killer */
+#define TIF_NOTIFY_SIGNAL	5	/* signal notifications exist */
 #define TIF_RESTORE_SIGMASK	6	/* restore signal mask in do_signal() */
 #define TIF_NOTIFY_RESUME	7	/* callback before returning to user */
 #define TIF_DB_DISABLED		8	/* debug trap disabled for syscall */
 #define TIF_SYSCALL_AUDIT	9	/* syscall auditing active */
 #define TIF_SECCOMP		10	/* secure computing */
+#define TIF_MEMDIE		11	/* is terminating due to OOM killer */
 
 #define _TIF_SYSCALL_TRACE	(1<<TIF_SYSCALL_TRACE)
 #define _TIF_SIGPENDING		(1<<TIF_SIGPENDING)
 #define _TIF_NEED_RESCHED	(1<<TIF_NEED_RESCHED)
 #define _TIF_SINGLESTEP		(1<<TIF_SINGLESTEP)
 #define _TIF_SYSCALL_TRACEPOINT	(1<<TIF_SYSCALL_TRACEPOINT)
+#define _TIF_NOTIFY_SIGNAL	(1<<TIF_NOTIFY_SIGNAL)
+#define _TIF_NOTIFY_RESUME	(1<<TIF_NOTIFY_RESUME)
 #define _TIF_SYSCALL_AUDIT	(1<<TIF_SYSCALL_AUDIT)
 #define _TIF_SECCOMP		(1<<TIF_SECCOMP)
 
diff --git a/arch/xtensa/kernel/entry.S b/arch/xtensa/kernel/entry.S
index 703cf6205efe..647b162f959b 100644
--- a/arch/xtensa/kernel/entry.S
+++ b/arch/xtensa/kernel/entry.S
@@ -500,8 +500,8 @@ common_exception_return:
 	 */
 
 	_bbsi.l	a4, TIF_NEED_RESCHED, 3f
-	_bbsi.l	a4, TIF_NOTIFY_RESUME, 2f
-	_bbci.l	a4, TIF_SIGPENDING, 5f
+	movi	a2, _TIF_SIGPENDING | _TIF_NOTIFY_RESUME | _TIF_NOTIFY_SIGNAL
+	bnone	a4, a2, 5f
 
 2:	l32i	a4, a1, PT_DEPC
 	bgeui	a4, VALID_DOUBLE_EXCEPTION_ADDRESS, 4f
diff --git a/arch/xtensa/kernel/signal.c b/arch/xtensa/kernel/signal.c
index 1fb1047f905c..c4d77dbfb61a 100644
--- a/arch/xtensa/kernel/signal.c
+++ b/arch/xtensa/kernel/signal.c
@@ -498,7 +498,8 @@ static void do_signal(struct pt_regs *regs)
 
 void do_notify_resume(struct pt_regs *regs)
 {
-	if (test_thread_flag(TIF_SIGPENDING))
+	if (test_thread_flag(TIF_SIGPENDING) ||
+	    test_thread_flag(TIF_NOTIFY_SIGNAL))
 		do_signal(regs);
 
 	if (test_thread_flag(TIF_NOTIFY_RESUME))