summaryrefslogtreecommitdiffstats
path: root/kernel/printk
diff options
context:
space:
mode:
authorJohn Ogness <john.ogness@linutronix.de>2024-02-26 13:07:24 +0106
committerGreg Kroah-Hartman <gregkh@linuxfoundation.org>2024-04-13 12:50:09 +0200
commit45f99d441067035dbb3f2a0d9713abe61ea721c5 (patch)
tree159aab68826248b4b1b87106c3ddedd3b638c482 /kernel/printk
parent10ca82aff58434e122c7c757cf0497c335f993f3 (diff)
downloadlinux-stable-45f99d441067035dbb3f2a0d9713abe61ea721c5.tar.gz
linux-stable-45f99d441067035dbb3f2a0d9713abe61ea721c5.tar.bz2
linux-stable-45f99d441067035dbb3f2a0d9713abe61ea721c5.zip
printk: Update @console_may_schedule in console_trylock_spinning()
[ Upstream commit 8076972468584d4a21dab9aa50e388b3ea9ad8c7 ] 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: dbdda842fe96 ("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>
Diffstat (limited to 'kernel/printk')
-rw-r--r--kernel/printk/printk.c6
1 files changed, 6 insertions, 0 deletions
diff --git a/kernel/printk/printk.c b/kernel/printk/printk.c
index 2ba16c426ba5..66c78dfd1792 100644
--- a/kernel/printk/printk.c
+++ b/kernel/printk/printk.c
@@ -1732,6 +1732,12 @@ 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;
}