timers: Add missing READ_ONCE() in __run_timer_base()

[ Upstream commit 1d4199cbbe ]

__run_timer_base() checks base::next_expiry without holding
base::lock. That can race with a remote CPU updating next_expiry under the
lock. This is an intentional and harmless data race, but lacks a
READ_ONCE(), so KCSAN complains about this.

Add the missing READ_ONCE(). All other places are covered already.

Fixes: 79f8b28e85 ("timers: Annotate possible non critical data race of next_expiry")
Reported-by: kernel test robot <oliver.sang@intel.com>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Reviewed-by: Frederic Weisbecker <frederic@kernel.org>
Link: https://lore.kernel.org/all/87a5emyqk0.ffs@tglx
Closes: https://lore.kernel.org/oe-lkp/202410301205.ef8e9743-lkp@intel.com
Signed-off-by: Sasha Levin <sashal@kernel.org>
This commit is contained in:
Thomas Gleixner 2024-10-30 08:53:51 +01:00 committed by Greg Kroah-Hartman
parent b62a8825d3
commit 1dfa6c5200

View File

@ -2422,7 +2422,8 @@ static inline void __run_timers(struct timer_base *base)
static void __run_timer_base(struct timer_base *base)
{
if (time_before(jiffies, base->next_expiry))
/* Can race against a remote CPU updating next_expiry under the lock */
if (time_before(jiffies, READ_ONCE(base->next_expiry)))
return;
timer_base_lock_expiry(base);