[PATCH v5 0/2] fix error flag covered by journal recovery

[PATCH v5 0/2] fix error flag covered by journal recovery

[Ye Bin]

From: Ye Bin <yebin10@huawei.com>

Diff v5 Vs v4:
Only commit error info to disk when bdev is not readonly.

Diff v4 Vs v3:
After journal replay recover 'es->s_state' error flag like recover error
info.

Diff v3 Vs v2:
Only fix fs error flag lost when previous journal errno is not record
in disk. As this may lead to drop orphan list, however fs not record
error flag, then fsck will not repair deeply.

Diff v2 vs v1:
Move call 'j_replay_prepare_callback' and 'j_replay_end_callback' from
ext4_load_journal() to jbd2_journal_recover().

When do fault injection test, got issue as follows:
EXT4-fs (dm-5): warning: mounting fs with errors, running e2fsck is recommended
EXT4-fs (dm-5): Errors on filesystem, clearing orphan list.
EXT4-fs (dm-5): recovery complete
EXT4-fs (dm-5): mounted filesystem with ordered data mode. Opts: data_err=abort,errors=remount-ro

EXT4-fs (dm-5): recovery complete
EXT4-fs (dm-5): mounted filesystem with ordered data mode. Opts: data_err=abort,errors=remount-ro

Without do file system check, file system is clean when do second mount.
Theoretically, the kernel will not clear fs error flag. In errors=remount-ro
mode the last super block is commit directly. So super block in journal is
not uptodate. When do jounral recovery, the uptodate super block will be
covered by jounral data. If super block submit all failed after recover
journal, then file system error flag is lost. When do "fsck -a" couldn't
repair file system deeply.
To solve above issue we need to do extra handle when do super block journal
recovery.

Ye Bin (2):
  ext4: commit super block if fs record error when journal record
    without error
  ext4: make sure fs error flag setted before clear journal error

 fs/ext4/super.c | 15 +++++++++++++--
 1 file changed, 13 insertions(+), 2 deletions(-)

-- 
2.31.1

[PATCH v5 1/2] ext4: commit super block if fs record error when journal record without error

[Ye Bin]

From: Ye Bin <yebin10@huawei.com>

Now, 'es->s_state' maybe covered by recover journal. And journal errno
maybe not recorded in journal sb as IO error. ext4_update_super() only
update error information when 'sbi->s_add_error_count' large than zero.
Then 'EXT4_ERROR_FS' flag maybe lost.
To solve above issue just recover 'es->s_state' error flag after journal
replay like error info.

Signed-off-by: Ye Bin <yebin10@huawei.com>
---
 fs/ext4/super.c | 9 +++++++++
 1 file changed, 9 insertions(+)

diff --git a/fs/ext4/super.c b/fs/ext4/super.c
index 88f7b8a88c76..dfa31eea1346 100644
--- a/fs/ext4/super.c
+++ b/fs/ext4/super.c
@@ -5920,6 +5920,7 @@ static int ext4_load_journal(struct super_block *sb,
 		err = jbd2_journal_wipe(journal, !really_read_only);
 	if (!err) {
 		char *save = kmalloc(EXT4_S_ERR_LEN, GFP_KERNEL);
+
 		if (save)
 			memcpy(save, ((char *) es) +
 			       EXT4_S_ERR_START, EXT4_S_ERR_LEN);
@@ -5928,6 +5929,14 @@ static int ext4_load_journal(struct super_block *sb,
 			memcpy(((char *) es) + EXT4_S_ERR_START,
 			       save, EXT4_S_ERR_LEN);
 		kfree(save);
+		es->s_state |= cpu_to_le16(EXT4_SB(sb)->s_mount_state &
+					   EXT4_ERROR_FS);
+		/* Write out restored error information to the superblock */
+		if (!bdev_read_only(sb->s_bdev)) {
+			int err2;
+			err2 = ext4_commit_super(sb);
+			err = err ? : err2;
+		}
 	}
 
 	if (err) {
-- 
2.31.1

[PATCH v5 2/2] ext4: make sure fs error flag setted before clear journal error

[Ye Bin]

From: Ye Bin <yebin10@huawei.com>

Now, jounral error number maybe cleared even though ext4_commit_super()
failed. This may lead to error flag miss, then fsck will miss to check
file system deeply.

Signed-off-by: Ye Bin <yebin10@huawei.com>
Reviewed-by: Jan Kara <jack@suse.cz>
---
 fs/ext4/super.c | 6 ++++--
 1 file changed, 4 insertions(+), 2 deletions(-)

diff --git a/fs/ext4/super.c b/fs/ext4/super.c
index dfa31eea1346..bf52b8a50717 100644
--- a/fs/ext4/super.c
+++ b/fs/ext4/super.c
@@ -6166,11 +6166,13 @@ static int ext4_clear_journal_err(struct super_block *sb,
 		errstr = ext4_decode_error(sb, j_errno, nbuf);
 		ext4_warning(sb, "Filesystem error recorded "
 			     "from previous mount: %s", errstr);
-		ext4_warning(sb, "Marking fs in need of filesystem check.");
 
 		EXT4_SB(sb)->s_mount_state |= EXT4_ERROR_FS;
 		es->s_state |= cpu_to_le16(EXT4_ERROR_FS);
-		ext4_commit_super(sb);
+		j_errno = ext4_commit_super(sb);
+		if (j_errno)
+			return j_errno;
+		ext4_warning(sb, "Marked fs in need of filesystem check.");
 
 		jbd2_journal_clear_err(journal);
 		jbd2_journal_update_sb_errno(journal);
-- 
2.31.1

Re: [PATCH v5 1/2] ext4: commit super block if fs record error when journal record without error

[Jan Kara]

On Tue 07-03-23 14:17:02, Ye Bin wrote:
> From: Ye Bin <yebin10@huawei.com>
> 
> Now, 'es->s_state' maybe covered by recover journal. And journal errno
> maybe not recorded in journal sb as IO error. ext4_update_super() only
> update error information when 'sbi->s_add_error_count' large than zero.
> Then 'EXT4_ERROR_FS' flag maybe lost.
> To solve above issue just recover 'es->s_state' error flag after journal
> replay like error info.
> 
> Signed-off-by: Ye Bin <yebin10@huawei.com>

Looks good to me. Feel free to add:

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

								Honza

> ---
>  fs/ext4/super.c | 9 +++++++++
>  1 file changed, 9 insertions(+)
> 
> diff --git a/fs/ext4/super.c b/fs/ext4/super.c
> index 88f7b8a88c76..dfa31eea1346 100644
> --- a/fs/ext4/super.c
> +++ b/fs/ext4/super.c
> @@ -5920,6 +5920,7 @@ static int ext4_load_journal(struct super_block *sb,
>  		err = jbd2_journal_wipe(journal, !really_read_only);
>  	if (!err) {
>  		char *save = kmalloc(EXT4_S_ERR_LEN, GFP_KERNEL);
> +
>  		if (save)
>  			memcpy(save, ((char *) es) +
>  			       EXT4_S_ERR_START, EXT4_S_ERR_LEN);
> @@ -5928,6 +5929,14 @@ static int ext4_load_journal(struct super_block *sb,
>  			memcpy(((char *) es) + EXT4_S_ERR_START,
>  			       save, EXT4_S_ERR_LEN);
>  		kfree(save);
> +		es->s_state |= cpu_to_le16(EXT4_SB(sb)->s_mount_state &
> +					   EXT4_ERROR_FS);
> +		/* Write out restored error information to the superblock */
> +		if (!bdev_read_only(sb->s_bdev)) {
> +			int err2;
> +			err2 = ext4_commit_super(sb);
> +			err = err ? : err2;
> +		}
>  	}
>  
>  	if (err) {
> -- 
> 2.31.1
> 
-- 
Jan Kara <jack@suse.com>
SUSE Labs, CR

Re: [PATCH v5 1/2] ext4: commit super block if fs record error when journal record without error

[Baokun Li]

On 2023/3/7 14:17, Ye Bin wrote:
> From: Ye Bin <yebin10@huawei.com>
>
> Now, 'es->s_state' maybe covered by recover journal. And journal errno
> maybe not recorded in journal sb as IO error. ext4_update_super() only
> update error information when 'sbi->s_add_error_count' large than zero.
> Then 'EXT4_ERROR_FS' flag maybe lost.
> To solve above issue just recover 'es->s_state' error flag after journal
> replay like error info.
>
> Signed-off-by: Ye Bin <yebin10@huawei.com>



Looks good to me.

Reviewed-by: Baokun Li <libaokun1@huawei.com>


> ---
>   fs/ext4/super.c | 9 +++++++++
>   1 file changed, 9 insertions(+)
>
> diff --git a/fs/ext4/super.c b/fs/ext4/super.c
> index 88f7b8a88c76..dfa31eea1346 100644
> --- a/fs/ext4/super.c
> +++ b/fs/ext4/super.c
> @@ -5920,6 +5920,7 @@ static int ext4_load_journal(struct super_block *sb,
>   		err = jbd2_journal_wipe(journal, !really_read_only);
>   	if (!err) {
>   		char *save = kmalloc(EXT4_S_ERR_LEN, GFP_KERNEL);
> +
>   		if (save)
>   			memcpy(save, ((char *) es) +
>   			       EXT4_S_ERR_START, EXT4_S_ERR_LEN);
> @@ -5928,6 +5929,14 @@ static int ext4_load_journal(struct super_block *sb,
>   			memcpy(((char *) es) + EXT4_S_ERR_START,
>   			       save, EXT4_S_ERR_LEN);
>   		kfree(save);
> +		es->s_state |= cpu_to_le16(EXT4_SB(sb)->s_mount_state &
> +					   EXT4_ERROR_FS);
> +		/* Write out restored error information to the superblock */
> +		if (!bdev_read_only(sb->s_bdev)) {
> +			int err2;
> +			err2 = ext4_commit_super(sb);
> +			err = err ? : err2;
> +		}
>   	}
>   
>   	if (err) {
-- 
With Best Regards,
Baokun Li
.