[PATCH 6.19 171/342] PM: sleep: Drop spurious WARN_ON() from pm_restore_gfp_mask()

Greg Kroah-Hartman
2026-03-31T16:38:37Z

From: Youngjun Park <youngjun.park@lge.com>

[ Upstream commit a8d51efb5929ae308895455a3e496b5eca2cd143 ]

Commit 35e4a69b2003f ("PM: sleep: Allow pm_restrict_gfp_mask()
stacking") introduced refcount-based GFP mask management that warns
when pm_restore_gfp_mask() is called with saved_gfp_count == 0.

Some hibernation paths call pm_restore_gfp_mask() defensively where
the GFP mask may or may not be restricted depending on the execution
path. For example, the uswsusp interface invokes it in
SNAPSHOT_CREATE_IMAGE, SNAPSHOT_UNFREEZE, and snapshot_release().
Before the stacking change this was a silent no-op; it now triggers
a spurious WARNING.

Remove the WARN_ON() wrapper from the !saved_gfp_count check while
retaining the check itself, so that defensive calls remain harmless
without producing false warnings.

Fixes: 35e4a69b2003f ("PM: sleep: Allow pm_restrict_gfp_mask() stacking")
Signed-off-by: Youngjun Park <youngjun.park@lge.com>
[ rjw: Subject tweak ]
Link: https://patch.msgid.link/20260322120528.750178-1-youngjun.park@lge.com
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
Signed-off-by: Sasha Levin <sashal@kernel.org>
---
kernel/power/main.c | 2 +-
1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/kernel/power/main.c b/kernel/power/main.c
index 03b2c5495c77a..9ce75b1a23ed3 100644
--- a/kernel/power/main.c
+++ b/kernel/power/main.c
@@ -40,7 +40,7 @@ void pm_restore_gfp_mask(void)
{
WARN_ON(!mutex_is_locked(&system_transition_mutex));

- if (WARN_ON(!saved_gfp_count) || --saved_gfp_count)
+ if (!saved_gfp_count || --saved_gfp_count)
return;

gfp_allowed_mask = saved_gfp_mask;
--
2.53.0