Re: [PATCH V2 2/2] xfs: Check if rt summary/bitmap buffers are logged with correct xfs_buf type

[Chandan Babu R <chandanrlinux@gmail.com>]

On Wednesday 16 September 2020 10:23:33 PM IST Darrick J. Wong wrote:
> On Wed, Sep 16, 2020 at 11:04:07AM +0530, Chandan Babu R wrote:
> > This commit adds a test to check if growing a real-time device can end
> > up logging an xfs_buf with the "type" subfield of
> > bip->bli_formats->blf_flags set to XFS_BLFT_UNKNOWN_BUF. When this
> > occurs the following call trace is printed on the console,
> > 
> > XFS: Assertion failed: (bip->bli_flags & XFS_BLI_STALE) || (xfs_blft_from_flags(&bip->__bli_format) > XFS_BLFT_UNKNOWN_BUF && xfs_blft_from_flags(&bip->__bli_format) < XFS_BLFT_MAX_BUF), file: fs/xfs/xfs_buf_item.c, line: 331
> > Call Trace:
> >  xfs_buf_item_format+0x632/0x680
> >  ? kmem_alloc_large+0x29/0x90
> >  ? kmem_alloc+0x70/0x120
> >  ? xfs_log_commit_cil+0x132/0x940
> >  xfs_log_commit_cil+0x26f/0x940
> >  ? xfs_buf_item_init+0x1ad/0x240
> >  ? xfs_growfs_rt_alloc+0x1fc/0x280
> >  __xfs_trans_commit+0xac/0x370
> >  xfs_growfs_rt_alloc+0x1fc/0x280
> >  xfs_growfs_rt+0x1a0/0x5e0
> >  xfs_file_ioctl+0x3fd/0xc70
> >  ? selinux_file_ioctl+0x174/0x220
> >  ksys_ioctl+0x87/0xc0
> >  __x64_sys_ioctl+0x16/0x20
> >  do_syscall_64+0x3e/0x70
> >  entry_SYSCALL_64_after_hwframe+0x44/0xa9
> > 
> > The kernel patch "xfs: Set xfs_buf type flag when growing summary/bitmap
> > files" is required to fix this issue.
> > 
> > Reviewed-by: Zorro Lang <zlang@redhat.com>
> > Signed-off-by: Chandan Babu R <chandanrlinux@gmail.com>
> > ---
> >  tests/xfs/260     | 53 +++++++++++++++++++++++++++++++++++++++++++++++
> >  tests/xfs/260.out |  2 ++
> >  tests/xfs/group   |  1 +
> >  3 files changed, 56 insertions(+)
> >  create mode 100755 tests/xfs/260
> >  create mode 100644 tests/xfs/260.out
> > 
> > diff --git a/tests/xfs/260 b/tests/xfs/260
> > new file mode 100755
> > index 00000000..078d4a11
> > --- /dev/null
> > +++ b/tests/xfs/260
> > @@ -0,0 +1,53 @@
> > +#! /bin/bash
> > +# SPDX-License-Identifier: GPL-2.0
> > +# Copyright (c) 2020 Chandan Babu R.  All Rights Reserved.
> > +#
> > +# FS QA Test 260
> > +#
> > +# Test to check if growing a real-time device can end up logging an xfs_buf with
> > +# the "type" subfield of bip->bli_formats->blf_flags set to
> > +# XFS_BLFT_UNKNOWN_BUF.
> > +#
> > +# This is a regression test for the kernel patch "xfs: Set xfs_buf type flag
> > +# when growing summary/bitmap files".
> > +
> > +seq=`basename $0`
> > +seqres=$RESULT_DIR/$seq
> > +echo "QA output created by $seq"
> > +
> > +here=`pwd`
> > +tmp=/tmp/$$
> > +status=1	# failure is the default!
> > +trap "_cleanup; exit \$status" 0 1 2 3 15
> > +
> > +_cleanup()
> > +{
> > +	cd /
> > +	rm -f $tmp.*
> > +}
> > +
> > +# get standard environment, filters and checks
> > +. ./common/rc
> > +. ./common/filter
> > +
> > +# remove previous $seqres.full before test
> > +rm -f $seqres.full
> > +
> > +# real QA test starts here
> > +_supported_fs xfs
> > +_supported_os Linux
> > +_require_realtime
> > +
> > +_scratch_mkfs -r size=10M  >> $seqres.full
> > +
> > +_scratch_mount >> $seqres.full
> > +
> > +$XFS_GROWFS_PROG $SCRATCH_MNT >> $seqres.full
> > +
> > +_scratch_unmount
> 
> Is this unmount crucial to exposing the bug?  Or does this post-test
> unmount and fsck suffice?

No, the above call to _scratch_unmount isn't required for recreating the
bug. I will remove it and post the patch once again.

> 
> (The rest of the logic looks ok to me.)
> 
> --D

-- 
chandan