On Sat, Jul 14, 2018 at 5:21 AM dann frazier <dann.frazier@xxxxxxxxxxxxx> wrote: > > On Thu, Jul 12, 2018 at 5:08 PM Theodore Y. Ts'o <tytso@xxxxxxx> wrote: > > > > > > > > Review console log and on each run I have filesystem rebuild. The problem > > > is that mke2fs I am using is 1.44.3-rc2. I am now reseting the environment > > > and re-test. > > > > > > > Could it be that you saw the error in ext4_validate_block_bitmap()? > > Looks like it. From Ike's report: > > # grep EXT4 d05-4-ipmi.log > [ 26.215587] EXT4-fs (sdb2): mounted filesystem with ordered data > mode. Opts: (null) > [ 29.844105] EXT4-fs (sdb2): re-mounted. Opts: errors=remount-ro > [ 3586.211348] EXT4-fs error (device sda2): > ext4_validate_block_bitmap:383: comm stress-ng: bg 4705: bad block > bitmap checksum > [ 8254.776992] EXT4-fs error (device sda2): > ext4_validate_block_bitmap:383: comm stress-ng: bg 4193: bad block > bitmap checksum > > I've ran my test case for several days w/ just the inode bitmap fix > and haven't been able to reproduce it - but perhaps that's just the > nature of the chdir test. hey Ted, Turns out the stress-ng 'mknod' test and - less reliably - the 'dentry' test can tickle the "bad block bitmap checksum" bug pretty easily. stress-ng wasn't *detecting* the error, but Colin has just released a new version that does. We've been running with your updated patch on 3 machines for several iterations, and have not seen another occurrence. -dann > > The patch which I sent Dann only fixed the problem for inode bitmaps; > > I noticed today that we need to fix it for block allocation bitmaps as > > well. > > I've also now ran several iterations w/ the block bitmap fix as well, > and still no problems, so: > > Tested-by: dann frazier <dann.frazier@xxxxxxxxxxxxx> > > > commit 8d5a803c6a6ce4ec258e31f76059ea5153ba46ef > > Author: Theodore Ts'o <tytso@xxxxxxx> > > Date: Thu Jul 12 19:08:05 2018 -0400 > > > > ext4: check for allocation block validity with block group locked > > > > With commit 044e6e3d74a3: "ext4: don't update checksum of new > > initialized bitmaps" the buffer valid bit will get set without > > actually setting up the checksum for the allocation bitmap, since the > > checksum will get calculated once we actually allocate an inode or > > block. > > > > If we are doing this, then we need to (re-)check the verified bit > > after we take the block group lock. Otherwise, we could race with > > another process reading and verifying the bitmap, which would then > > complain about the checksum being invalid. > > > > https://bugs.launchpad.net/ubuntu/+source/linux/+bug/1780137 > > > > Signed-off-by: Theodore Ts'o <tytso@xxxxxxx> > > Cc: stable@xxxxxxxxxx > > Would it also make sense to add the following? > > Fixes: 044e6e3d74a3 ("ext4: don't update checksum of new initialized bitmaps") > > -dann > > > diff --git a/fs/ext4/balloc.c b/fs/ext4/balloc.c > > index e68cefe08261..aa52d87985aa 100644 > > --- a/fs/ext4/balloc.c > > +++ b/fs/ext4/balloc.c > > @@ -368,6 +368,8 @@ static int ext4_validate_block_bitmap(struct super_block *sb, > > return -EFSCORRUPTED; > > > > ext4_lock_group(sb, block_group); > > + if (buffer_verified(bh)) > > + goto verified; > > if (unlikely(!ext4_block_bitmap_csum_verify(sb, block_group, > > desc, bh))) { > > ext4_unlock_group(sb, block_group); > > @@ -386,6 +388,7 @@ static int ext4_validate_block_bitmap(struct super_block *sb, > > return -EFSCORRUPTED; > > } > > set_buffer_verified(bh); > > +verified: > > ext4_unlock_group(sb, block_group); > > return 0; > > } > > diff --git a/fs/ext4/ialloc.c b/fs/ext4/ialloc.c > > index fb83750c1a14..e9d8e2667ab5 100644 > > --- a/fs/ext4/ialloc.c > > +++ b/fs/ext4/ialloc.c > > @@ -90,6 +90,8 @@ static int ext4_validate_inode_bitmap(struct super_block *sb, > > return -EFSCORRUPTED; > > > > ext4_lock_group(sb, block_group); > > + if (buffer_verified(bh)) > > + goto verified; > > blk = ext4_inode_bitmap(sb, desc); > > if (!ext4_inode_bitmap_csum_verify(sb, block_group, desc, bh, > > EXT4_INODES_PER_GROUP(sb) / 8)) { > > @@ -101,6 +103,7 @@ static int ext4_validate_inode_bitmap(struct super_block *sb, > > return -EFSBADCRC; > > } > > set_buffer_verified(bh); > > +verified: > > ext4_unlock_group(sb, block_group); > > return 0; > > }
