On Wed, Jul 30, 2014 at 11:48:48AM +1000, Dave Chinner wrote: > From: Dave Chinner <dchinner@xxxxxxxxxx> > > When running xfs/305, I noticed that quotacheck was flushing dquot > buffers that did not have the xfs_dquot_buf_ops verifiers attached: > > XFS (vdb): _xfs_buf_ioapply: no ops on block 0x1dc8/0x1dc8 > ffff880052489000: 44 51 01 04 00 00 65 b8 00 00 00 00 00 00 00 00 DQ....e......... > ffff880052489010: 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 ................ > ffff880052489020: 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 ................ > ffff880052489030: 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 ................ > CPU: 1 PID: 2376 Comm: mount Not tainted 3.16.0-rc2-dgc+ #306 > Hardware name: QEMU Standard PC (i440FX + PIIX, 1996), BIOS Bochs 01/01/2011 > ffff88006fe38000 ffff88004a0ffae8 ffffffff81cf1cca 0000000000000001 > ffff88004a0ffb88 ffffffff814d50ca 000010004a0ffc70 0000000000000000 > ffff88006be56dc4 0000000000000021 0000000000001dc8 ffff88007c773d80 > Call Trace: > [<ffffffff81cf1cca>] dump_stack+0x45/0x56 > [<ffffffff814d50ca>] _xfs_buf_ioapply+0x3ca/0x3d0 > [<ffffffff810db520>] ? wake_up_state+0x20/0x20 > [<ffffffff814d51f5>] ? xfs_bdstrat_cb+0x55/0xb0 > [<ffffffff814d513b>] xfs_buf_iorequest+0x6b/0xd0 > [<ffffffff814d51f5>] xfs_bdstrat_cb+0x55/0xb0 > [<ffffffff814d53ab>] __xfs_buf_delwri_submit+0x15b/0x220 > [<ffffffff814d6040>] ? xfs_buf_delwri_submit+0x30/0x90 > [<ffffffff814d6040>] xfs_buf_delwri_submit+0x30/0x90 > [<ffffffff8150f89d>] xfs_qm_quotacheck+0x17d/0x3c0 > [<ffffffff81510591>] xfs_qm_mount_quotas+0x151/0x1e0 > [<ffffffff814ed01c>] xfs_mountfs+0x56c/0x7d0 > [<ffffffff814f0f12>] xfs_fs_fill_super+0x2c2/0x340 > [<ffffffff811c9fe4>] mount_bdev+0x194/0x1d0 > [<ffffffff814f0c50>] ? xfs_finish_flags+0x170/0x170 > [<ffffffff814ef0f5>] xfs_fs_mount+0x15/0x20 > [<ffffffff811ca8c9>] mount_fs+0x39/0x1b0 > [<ffffffff811e4d67>] vfs_kern_mount+0x67/0x120 > [<ffffffff811e757e>] do_mount+0x23e/0xad0 > [<ffffffff8117abde>] ? __get_free_pages+0xe/0x50 > [<ffffffff811e71e6>] ? copy_mount_options+0x36/0x150 > [<ffffffff811e8103>] SyS_mount+0x83/0xc0 > [<ffffffff81cfd40b>] tracesys+0xdd/0xe2 > > This was caused by dquot buffer readahead not attaching a verifier > structure to the buffer when readahead was issued, resulting in the > followup read of the buffer finding a valid buffer and so not > attaching new verifiers to the buffer as part of the read. > > Also, when a verifier failure occurs, we then read the buffer > without verifiers. Attach the verifiers manually after this read so > that if the buffer is then written it will be verified that the > corruption has been repaired. > > Further, when flushing a dquot we don't ask for a verifier when > reading in the dquot buffer the dquot belongs to. Most of the time > this isn't an issue because the buffer is still cached, but when it > is not cached it will result in writing the dquot buffer without > having the verfier attached. > > Signed-off-by: Dave Chinner <dchinner@xxxxxxxxxx> > --- Reviewed-by: Brian Foster <bfoster@xxxxxxxxxx> > fs/xfs/xfs_dquot.c | 3 ++- > fs/xfs/xfs_qm.c | 8 +++++++- > 2 files changed, 9 insertions(+), 2 deletions(-) > > diff --git a/fs/xfs/xfs_dquot.c b/fs/xfs/xfs_dquot.c > index 8a44a79..63c2de4 100644 > --- a/fs/xfs/xfs_dquot.c > +++ b/fs/xfs/xfs_dquot.c > @@ -974,7 +974,8 @@ xfs_qm_dqflush( > * Get the buffer containing the on-disk dquot > */ > error = xfs_trans_read_buf(mp, NULL, mp->m_ddev_targp, dqp->q_blkno, > - mp->m_quotainfo->qi_dqchunklen, 0, &bp, NULL); > + mp->m_quotainfo->qi_dqchunklen, 0, &bp, > + &xfs_dquot_buf_ops); > if (error) > goto out_unlock; > > diff --git a/fs/xfs/xfs_qm.c b/fs/xfs/xfs_qm.c > index 7e1a80b..1023210 100644 > --- a/fs/xfs/xfs_qm.c > +++ b/fs/xfs/xfs_qm.c > @@ -911,6 +911,12 @@ xfs_qm_dqiter_bufs( > if (error) > break; > > + /* > + * A corrupt buffer might not have a verifier attached, so > + * make sure we have the correct one attached before writeback > + * occurs. > + */ > + bp->b_ops = &xfs_dquot_buf_ops; > xfs_qm_reset_dqcounts(mp, bp, firstid, type); > xfs_buf_delwri_queue(bp, buffer_list); > xfs_buf_relse(bp); > @@ -996,7 +1002,7 @@ xfs_qm_dqiterate( > xfs_buf_readahead(mp->m_ddev_targp, > XFS_FSB_TO_DADDR(mp, rablkno), > mp->m_quotainfo->qi_dqchunklen, > - NULL); > + &xfs_dquot_buf_ops); > rablkno++; > } > } > -- > 2.0.0 > > _______________________________________________ > xfs mailing list > xfs@xxxxxxxxxxx > http://oss.sgi.com/mailman/listinfo/xfs _______________________________________________ xfs mailing list xfs@xxxxxxxxxxx http://oss.sgi.com/mailman/listinfo/xfs
