printk: Update @console_may_schedule in console_trylock_spinning()

[ Upstream commit 8076972468 ]

console_trylock_spinning() may takeover the console lock from a
schedulable context. Update @console_may_schedule to make sure it
reflects a trylock acquire.

Reported-by: Mukesh Ojha <quic_mojha@quicinc.com>
Closes: https://lore.kernel.org/lkml/20240222090538.23017-1-quic_mojha@quicinc.com
Fixes: dbdda842fe ("printk: Add console owner and waiter logic to load balance console writes")
Signed-off-by: John Ogness <john.ogness@linutronix.de>
Reviewed-by: Mukesh Ojha <quic_mojha@quicinc.com>
Reviewed-by: Petr Mladek <pmladek@suse.com>
Link: https://lore.kernel.org/r/875xybmo2z.fsf@jogness.linutronix.de
Signed-off-by: Petr Mladek <pmladek@suse.com>
Signed-off-by: Sasha Levin <sashal@kernel.org>
This commit is contained in:
John Ogness 2024-02-26 13:07:24 +01:06 committed by Greg Kroah-Hartman
parent 2280bb8577
commit 9bd2f11ac9
1 changed files with 6 additions and 0 deletions

View File

@ -1908,6 +1908,12 @@ static int console_trylock_spinning(void)
*/
mutex_acquire(&console_lock_dep_map, 0, 1, _THIS_IP_);
/*
* Update @console_may_schedule for trylock because the previous
* owner may have been schedulable.
*/
console_may_schedule = 0;
return 1;
}