while true; do xfs_freeze -f a_mount; \
    xfs_freeze -u a_mount; done" &
  # taskset -c 3 bash -c "while true; do quotaon a_mount; \
    quotaoff a_mount; done" &

Adding cond_resched() to the retry loop fixes the issue. It acts as an
RCU quiescent state, allowing synchronize_rcu() in percpu_down_write()
to complete.

Fixes: 576215cffdef ("fs: Drop wait_unfrozen wait queue")
Signed-off-by: Abhishek Bapat <abhishekbapat@google.com>
Link: https://patch.msgid.link/20260115213103.1089129-1-abhishekbapat@google.com
Signed-off-by: Jan Kara <jack@suse.cz>
Signed-off-by: Sasha Levin <sashal@kernel.org>
---
 fs/quota/quota.c | 1 +
 1 file changed, 1 insertion(+)

diff --git a/fs/quota/quota.c b/fs/quota/quota.c
index 7c2b75a444852..de4379a9c7920 100644
--- a/fs/quota/quota.c
+++ b/fs/quota/quota.c
@@ -899,6 +899,7 @@ static struct super_block *quotactl_block(const char __user *special, int cmd)
 		sb_start_write(sb);
 		sb_end_write(sb);
 		put_super(sb);
+		cond_resched();
 		goto retry;
 	}
 	return sb;
-- 
2.51.0[PATCH 6.18 251/641] quota: fix livelock between quotactl and freeze_superGreg Kroah-Hartman <gregkh@linuxfoundation.org> undefinedstable@vger.kernel.org undefined undefined undefined undefined undefinedŚ:†“M