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| author | Dmitry Monakhov <dmonakhov@openvz.org> | 2013-06-13 02:38:04 (GMT) |
|---|---|---|
| committer | Theodore Ts'o <tytso@mit.edu> | 2013-06-13 02:38:04 (GMT) |
| commit | 4418e14112e3ca85e8492a4489a3552b0cc526a8 (patch) | |
| tree | 93abfabff161cc2f5b09d7aaf6aa4ae09ba13c7b /fs/ext4/super.c | |
| parent | 06a407f13daf9e48f0ef7189c7e54082b53940c7 (diff) | |
| download | linux-4418e14112e3ca85e8492a4489a3552b0cc526a8.tar.xz | |
ext4: Fix fsync error handling after filesystem abort
If filesystem was aborted after inode's write back is complete
but before its metadata was updated we may return success
results in data loss.
In order to handle fs abort correctly we have to check
fs state once we discover that it is in MS_RDONLY state
Test case: http://patchwork.ozlabs.org/patch/244297
Reviewed-by: Jan Kara <jack@suse.cz>
Signed-off-by: Dmitry Monakhov <dmonakhov@openvz.org>
Signed-off-by: "Theodore Ts'o" <tytso@mit.edu>
Diffstat (limited to 'fs/ext4/super.c')
| -rw-r--r-- | fs/ext4/super.c | 12 |
1 files changed, 11 insertions, 1 deletions
diff --git a/fs/ext4/super.c b/fs/ext4/super.c index 0f77c2e..eb52a7b 100644 --- a/fs/ext4/super.c +++ b/fs/ext4/super.c @@ -399,6 +399,11 @@ static void ext4_handle_error(struct super_block *sb) } if (test_opt(sb, ERRORS_RO)) { ext4_msg(sb, KERN_CRIT, "Remounting filesystem read-only"); + /* + * Make sure updated value of ->s_mount_flags will be visible + * before ->s_flags update + */ + smp_wmb(); sb->s_flags |= MS_RDONLY; } if (test_opt(sb, ERRORS_PANIC)) @@ -571,8 +576,13 @@ void __ext4_abort(struct super_block *sb, const char *function, if ((sb->s_flags & MS_RDONLY) == 0) { ext4_msg(sb, KERN_CRIT, "Remounting filesystem read-only"); - sb->s_flags |= MS_RDONLY; EXT4_SB(sb)->s_mount_flags |= EXT4_MF_FS_ABORTED; + /* + * Make sure updated value of ->s_mount_flags will be visible + * before ->s_flags update + */ + smp_wmb(); + sb->s_flags |= MS_RDONLY; if (EXT4_SB(sb)->s_journal) jbd2_journal_abort(EXT4_SB(sb)->s_journal, -EIO); save_error_info(sb, function, line); |