Commit 8f984530 authored by Baokun Li's avatar Baokun Li Committed by Theodore Ts'o
Browse files

ext4: correct behavior under errors=remount-ro mode 

And after commit 95257987 ("ext4: drop EXT4_MF_FS_ABORTED flag") in
v6.6-rc1, the EXT4_FLAGS_SHUTDOWN bit is set in ext4_handle_error() under
errors=remount-ro mode. This causes the read to fail even when the error
is triggered in errors=remount-ro mode.

To correct the behavior under errors=remount-ro, EXT4_FLAGS_SHUTDOWN is
replaced by the newly introduced EXT4_FLAGS_EMERGENCY_RO. This new flag
only prevents writes, matching the previous behavior with SB_RDONLY.

Fixes: 95257987 ("ext4: drop EXT4_MF_FS_ABORTED flag")
Closes: https://lore.kernel.org/all/22d652f6-cb3c-43f5-b2fe-0a4bb6516a04@huawei.com/


Suggested-by: default avatarJan Kara <jack@suse.cz>
Signed-off-by: default avatarBaokun Li <libaokun1@huawei.com>
Reviewed-by: default avatarZhang Yi <yi.zhang@huawei.com>
Reviewed-by: default avatarJan Kara <jack@suse.cz>
Link: https://patch.msgid.link/20250122114130.229709-6-libaokun@huaweicloud.com


Signed-off-by: default avatarTheodore Ts'o <tytso@mit.edu>
parent 5bc27f4d

fs/ext4/super.c

+8 −11
Original line number Diff line number Diff line
@@ -693,11 +693,8 @@ static void ext4_handle_error(struct super_block *sb, bool force_ro, int error, 
	if (test_opt(sb, WARN_ON_ERROR))

		WARN_ON_ONCE(1);



	if (!continue_fs && !sb_rdonly(sb)) {

		set_bit(EXT4_FLAGS_SHUTDOWN, &EXT4_SB(sb)->s_ext4_flags);

		if (journal)

	if (!continue_fs && !ext4_emergency_ro(sb) && journal)

		jbd2_journal_abort(journal, -EIO);

	}



	if (!bdev_read_only(sb->s_bdev)) {

		save_error_info(sb, error, ino, block, func, line);
@@ -723,17 +720,17 @@ static void ext4_handle_error(struct super_block *sb, bool force_ro, int error, 
			sb->s_id);

	}



	if (sb_rdonly(sb) || continue_fs)

	if (ext4_emergency_ro(sb) || continue_fs)

		return;



	ext4_msg(sb, KERN_CRIT, "Remounting filesystem read-only");

	/*

	 * EXT4_FLAGS_SHUTDOWN was set which stops all filesystem

	 * modifications. We don't set SB_RDONLY because that requires

	 * sb->s_umount semaphore and setting it without proper remount

	 * procedure is confusing code such as freeze_super() leading to

	 * deadlocks and other problems.

	 * We don't set SB_RDONLY because that requires sb->s_umount

	 * semaphore and setting it without proper remount procedure is

	 * confusing code such as freeze_super() leading to deadlocks

	 * and other problems.

	 */

	set_bit(EXT4_FLAGS_EMERGENCY_RO, &EXT4_SB(sb)->s_ext4_flags);

}



static void update_super_work(struct work_struct *work)