ext4: clear lockdep subtype for quota files on quota off (964edf66) · Commits · 戴 / test

Quota files have special ranking of i_data_sem lock. We inform lockdep about it when turning on quotas however when turning quotas off, we don't clear the lockdep subclass from i_data_sem lock and thus when the inode gets later reused for a normal file or directory, lockdep gets confused and complains about possible deadlocks. Fix the problem by resetting lockdep subclass of i_data_sem on quota off. Cc: stable@vger.kernel.org Fixes: Reported-and-tested-by:

Ross Zwisler <ross.zwisler@linux.intel.com> Reviewed-by:

Andreas Dilger <adilger@dilger.ca> Signed-off-by:

Jan Kara <jack@suse.cz> Signed-off-by:

Theodore Ts'o <tytso@mit.edu>

fs/ext4/super.c

+5 −9

Original line number	Diff line number	Diff line
		@@ -848,15 +848,10 @@ static inline void ext4_quota_off_umount(struct super_block *sb)
		{
		int type;

		if (ext4_has_feature_quota(sb)) {
		dquot_disable(sb, -1,
		DQUOT_USAGE_ENABLED \| DQUOT_LIMITS_ENABLED);
		} else {
		/* Use our quota_off function to clear inode flags etc. */
		for (type = 0; type < EXT4_MAXQUOTAS; type++)
		ext4_quota_off(sb, type);
		}
		}
		#else
		static inline void ext4_quota_off_umount(struct super_block *sb)
		{
		@@ -5485,7 +5480,7 @@ static int ext4_quota_off(struct super_block *sb, int type)
		goto out;

		err = dquot_quota_off(sb, type);
		if (err)
		if (err \|\| ext4_has_feature_quota(sb))
		goto out_put;

		inode_lock(inode);
		@@ -5505,6 +5500,7 @@ static int ext4_quota_off(struct super_block *sb, int type)
		out_unlock:
		inode_unlock(inode);
		out_put:
		lockdep_set_quota_inode(inode, I_DATA_SEM_NORMAL);
		iput(inode);
		return err;
		out:

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