Message ID | 1467495762-25353-1-git-send-email-vegard.nossum@oracle.com (mailing list archive) |
---|---|
State | New, archived |
Headers | show |
On Sat, Jul 02, 2016 at 11:42:42PM +0200, Vegard Nossum wrote: > Certain combinations of mount options in the superblock will cause > set_journal_csum_feature_set() in ext4_fill_super() to fail after the > journal has been created. When iput() is called on the journal inode, > we will hit the BUG() in ext4_should_journal_data(). We can prevent > this by only calling ext4_should_journal_data() if we already know > that it's not the journal inode. Which mount options? Can you please give a reproducer? - Ted -- To unsubscribe from this list: send the line "unsubscribe linux-fsdevel" in the body of a message to majordomo@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html
On 07/03/2016 07:15 AM, Theodore Ts'o wrote: > On Sat, Jul 02, 2016 at 11:42:42PM +0200, Vegard Nossum wrote: >> Certain combinations of mount options in the superblock will cause >> set_journal_csum_feature_set() in ext4_fill_super() to fail after the >> journal has been created. When iput() is called on the journal inode, >> we will hit the BUG() in ext4_should_journal_data(). We can prevent >> this by only calling ext4_should_journal_data() if we already know >> that it's not the journal inode. > > Which mount options? Can you please give a reproducer? Unfortunately I can't share the reproducer, but... s->mount_opt = 0xa882c020, which seems like it is: EXT4_MOUNT_ERRORS_RO EXT4_MOUNT_XATTR_USER EXT4_MOUNT_POSIX_ACL EXT4_MOUNT_BARRIER EXT4_MOUNT_JOURNAL_CHECKSUM EXT4_MOUNT_DELALLOC EXT4_MOUNT_BLOCK_VALIDITY EXT4_MOUNT_INIT_INODE_TABLE At mount time, this ends up calling jbd2_journal_clear_features(JBD2_FEATURE_COMPAT_CHECKSUM, 0, JBD2_FEATURE_INCOMPAT_CSUM_V3 | JBD2_FEATURE_INCOMPAT_CSUM_V2) jbd2_journal_set_features(0, 0, JBD2_FEATURE_INCOMPAT_CSUM_V3) = 0 // fails jbd2_journal_clear_features(0x0, 0x0, JBD2_FEATURE_INCOMPAT_ASYNC_COMMIT) The reason the set_features() call ends up calling is because journal->j_format_version == 1. Maybe the "mount options" thing was a bit misleading and we should rather say "Certain combinations of mount options (EXT4_MOUNT_JOURNAL_CHECKSUM), journal format (v1), and superblock features (EXT4_FEATURE_RO_COMPAT_METADATA_CSUM) [...]" in the changelog. Does that make more sense? Hope this helps, Vegard -- To unsubscribe from this list: send the line "unsubscribe linux-fsdevel" in the body of a message to majordomo@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html
On Sat 02-07-16 23:42:42, Vegard Nossum wrote: > Certain combinations of mount options in the superblock will cause > set_journal_csum_feature_set() in ext4_fill_super() to fail after the > journal has been created. When iput() is called on the journal inode, > we will hit the BUG() in ext4_should_journal_data(). We can prevent > this by only calling ext4_should_journal_data() if we already know > that it's not the journal inode. > > Fixes: 2d859db3e4 ("ext4: fix data corruption in inodes with journalled data") > Fixes: 2b405bfa84 ("ext4: fix data=journal fast mount/umount hang") > Cc: Jan Kara <jack@suse.cz> > Cc: stable@vger.kernel.org > Signed-off-by: Vegard Nossum <vegard.nossum@oracle.com> The patch looks good. You can add: Reviewed-by: Jan Kara <jack@suse.cz> Honza > --- > fs/ext4/inode.c | 6 +++--- > 1 file changed, 3 insertions(+), 3 deletions(-) > > diff --git a/fs/ext4/inode.c b/fs/ext4/inode.c > index 91b66db..2591236 100644 > --- a/fs/ext4/inode.c > +++ b/fs/ext4/inode.c > @@ -207,9 +207,9 @@ void ext4_evict_inode(struct inode *inode) > * Note that directories do not have this problem because they > * don't use page cache. > */ > - if (ext4_should_journal_data(inode) && > - (S_ISLNK(inode->i_mode) || S_ISREG(inode->i_mode)) && > - inode->i_ino != EXT4_JOURNAL_INO) { > + if (inode->i_ino != EXT4_JOURNAL_INO && > + ext4_should_journal_data(inode) && > + (S_ISLNK(inode->i_mode) || S_ISREG(inode->i_mode))) { > journal_t *journal = EXT4_SB(inode->i_sb)->s_journal; > tid_t commit_tid = EXT4_I(inode)->i_datasync_tid; > > -- > 1.9.1 >
Thanks, I've reworded the commit description as follows: ext4: don't call ext4_should_journal_data() on the journal inode If ext4_fill_super() fails early, it's possible for ext4_evict_inode() to call ext4_should_journal_data() before superblock options and flags are fully set up. In that case, the iput() on the journal inode can end up causing a BUG(). Work around this problem by reordering the tests so we only call ext4_should_journal_data() after we know it's not the journal inode. Fixes: 2d859db3e4 ("ext4: fix data corruption in inodes with journalled data") Fixes: 2b405bfa84 ("ext4: fix data=journal fast mount/umount hang") Cc: Jan Kara <jack@suse.cz> Cc: stable@vger.kernel.org Signed-off-by: Vegard Nossum <vegard.nossum@oracle.com> Signed-off-by: Theodore Ts'o <tytso@mit.edu> Reviewed-by: Jan Kara <jack@suse.cz> -- To unsubscribe from this list: send the line "unsubscribe linux-fsdevel" in the body of a message to majordomo@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html
diff --git a/fs/ext4/inode.c b/fs/ext4/inode.c index 91b66db..2591236 100644 --- a/fs/ext4/inode.c +++ b/fs/ext4/inode.c @@ -207,9 +207,9 @@ void ext4_evict_inode(struct inode *inode) * Note that directories do not have this problem because they * don't use page cache. */ - if (ext4_should_journal_data(inode) && - (S_ISLNK(inode->i_mode) || S_ISREG(inode->i_mode)) && - inode->i_ino != EXT4_JOURNAL_INO) { + if (inode->i_ino != EXT4_JOURNAL_INO && + ext4_should_journal_data(inode) && + (S_ISLNK(inode->i_mode) || S_ISREG(inode->i_mode))) { journal_t *journal = EXT4_SB(inode->i_sb)->s_journal; tid_t commit_tid = EXT4_I(inode)->i_datasync_tid;
Certain combinations of mount options in the superblock will cause set_journal_csum_feature_set() in ext4_fill_super() to fail after the journal has been created. When iput() is called on the journal inode, we will hit the BUG() in ext4_should_journal_data(). We can prevent this by only calling ext4_should_journal_data() if we already know that it's not the journal inode. Fixes: 2d859db3e4 ("ext4: fix data corruption in inodes with journalled data") Fixes: 2b405bfa84 ("ext4: fix data=journal fast mount/umount hang") Cc: Jan Kara <jack@suse.cz> Cc: stable@vger.kernel.org Signed-off-by: Vegard Nossum <vegard.nossum@oracle.com> --- fs/ext4/inode.c | 6 +++--- 1 file changed, 3 insertions(+), 3 deletions(-)