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From: Dan Carpenter <dan.carpenter@oracle.com>
To: Jan Kara <jack@suse.com>
Cc: linux-ext4@vger.kernel.org, linux-kernel@vger.kernel.org,
	kernel-janitors@vger.kernel.org
Subject: [PATCH] ext2: do not sleep in ext2_error()
Date: Fri, 3 Sep 2021 12:05:38 +0300	[thread overview]
Message-ID: <20210903090538.GA7283@kili> (raw)

No one expects error logging functions to sleep so sometimes they are
called with spinlocks held.  In this case the problematic call tree is:

ext2_statfs() <- disables preempt
-> ext2_count_free_inodes()
   -> ext2_get_group_desc()
      -> ext2_error()

Signed-off-by: Dan Carpenter <dan.carpenter@oracle.com>
---
This is just from static analysis.  NOT TESTED!

Probably a safer fix would be to just call pr_err() instead of
ext2_error() in ext2_get_group_desc().  I can send that fix instead if
people want.

 fs/ext2/super.c | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/fs/ext2/super.c b/fs/ext2/super.c
index d8d580b609ba..ba345ab860f0 100644
--- a/fs/ext2/super.c
+++ b/fs/ext2/super.c
@@ -59,7 +59,7 @@ void ext2_error(struct super_block *sb, const char *function,
 		sbi->s_mount_state |= EXT2_ERROR_FS;
 		es->s_state |= cpu_to_le16(EXT2_ERROR_FS);
 		spin_unlock(&sbi->s_lock);
-		ext2_sync_super(sb, es, 1);
+		ext2_sync_super(sb, es, 0);
 	}
 
 	va_start(args, fmt);
-- 
2.20.1


             reply	other threads:[~2021-09-03  9:06 UTC|newest]

Thread overview: 4+ messages / expand[flat|nested]  mbox.gz  Atom feed  top
2021-09-03  9:05 Dan Carpenter [this message]
2021-09-03 12:48 ` [PATCH] ext2: do not sleep in ext2_error() Theodore Ts'o
2021-09-03 13:09   ` Dan Carpenter
2021-09-16  9:48   ` Jan Kara

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