[PATCH 19/68] XTENSA: iss/console, fix potential deadlock
From: Jiri Slaby <hidden>
Date: 2012-03-05 13:55:39
Also in:
lkml
Subsystem:
tensilica xtensa port (xtensa), the rest · Maintainers:
Chris Zankel, Max Filippov, Linus Torvalds
If the timer ticks while we are holding the spinlock, the system deadlocks. It is due to synchronous del_timer. So to fix that, use spinlocks that properly disable bottom halves. Signed-off-by: Jiri Slaby <redacted> Cc: Chris Zankel <chris@zankel.net> --- arch/xtensa/platforms/iss/console.c | 5 ++--- 1 file changed, 2 insertions(+), 3 deletions(-)
diff --git a/arch/xtensa/platforms/iss/console.c b/arch/xtensa/platforms/iss/console.c
index 01842e4..94ab8ec 100644
--- a/arch/xtensa/platforms/iss/console.c
+++ b/arch/xtensa/platforms/iss/console.c@@ -91,11 +91,10 @@ static int rs_open(struct tty_struct *tty, struct file * filp) */ static void rs_close(struct tty_struct *tty, struct file * filp) { - spin_lock(&timer_lock); + spin_lock_bh(&timer_lock); if (tty->count == 1) - /* this will cause a deadlock if the timer ticks right now */ del_timer_sync(&serial_timer); - spin_unlock(&timer_lock); + spin_unlock_bh(&timer_lock); }
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1.7.9.2