diff options
Diffstat (limited to 'features/rt/timers-Move-clearing-of-base-timer_running-under-bas.patch')
| -rw-r--r-- | features/rt/timers-Move-clearing-of-base-timer_running-under-bas.patch | 62 |
1 files changed, 0 insertions, 62 deletions
diff --git a/features/rt/timers-Move-clearing-of-base-timer_running-under-bas.patch b/features/rt/timers-Move-clearing-of-base-timer_running-under-bas.patch deleted file mode 100644 index c95178d3..00000000 --- a/features/rt/timers-Move-clearing-of-base-timer_running-under-bas.patch +++ /dev/null @@ -1,62 +0,0 @@ -From 13ae7118b5e43a9fd44640f31eb1df12f580a13e Mon Sep 17 00:00:00 2001 -From: Thomas Gleixner <tglx@linutronix.de> -Date: Sun, 6 Dec 2020 22:40:07 +0100 -Subject: [PATCH 002/191] timers: Move clearing of base::timer_running under - base::lock - -syzbot reported KCSAN data races vs. timer_base::timer_running being set to -NULL without holding base::lock in expire_timers(). - -This looks innocent and most reads are clearly not problematic but for a -non-RT kernel it's completely irrelevant whether the store happens before -or after taking the lock. For an RT kernel moving the store under the lock -requires an extra unlock/lock pair in the case that there is a waiter for -the timer. But that's not the end of the world and definitely not worth the -trouble of adding boatloads of comments and annotations to the code. Famous -last words... - -Reported-by: syzbot+aa7c2385d46c5eba0b89@syzkaller.appspotmail.com -Reported-by: syzbot+abea4558531bae1ba9fe@syzkaller.appspotmail.com -Link: https://lkml.kernel.org/r/87lfea7gw8.fsf@nanos.tec.linutronix.de -Signed-off-by: Thomas Gleixner <tglx@linutronix.de> -Signed-off-by: Sebastian Andrzej Siewior <bigeasy@linutronix.de> -Cc: stable-rt@vger.kernel.org ---- - kernel/time/timer.c | 6 ++++-- - 1 file changed, 4 insertions(+), 2 deletions(-) - -diff --git a/kernel/time/timer.c b/kernel/time/timer.c -index f475f1a027c8..a0ec4450b1d8 100644 ---- a/kernel/time/timer.c -+++ b/kernel/time/timer.c -@@ -1277,8 +1277,10 @@ static inline void timer_base_unlock_expiry(struct timer_base *base) - static void timer_sync_wait_running(struct timer_base *base) - { - if (atomic_read(&base->timer_waiters)) { -+ raw_spin_unlock_irq(&base->lock); - spin_unlock(&base->expiry_lock); - spin_lock(&base->expiry_lock); -+ raw_spin_lock_irq(&base->lock); - } - } - -@@ -1469,14 +1471,14 @@ static void expire_timers(struct timer_base *base, struct hlist_head *head) - if (timer->flags & TIMER_IRQSAFE) { - raw_spin_unlock(&base->lock); - call_timer_fn(timer, fn, baseclk); -- base->running_timer = NULL; - raw_spin_lock(&base->lock); -+ base->running_timer = NULL; - } else { - raw_spin_unlock_irq(&base->lock); - call_timer_fn(timer, fn, baseclk); -+ raw_spin_lock_irq(&base->lock); - base->running_timer = NULL; - timer_sync_wait_running(base); -- raw_spin_lock_irq(&base->lock); - } - } - } --- -2.19.1 - |