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

["Darrick J. Wong" <darrick.wong@oracle.com>]

On Mon, Sep 14, 2020 at 06:34:56PM +0800, Zorro Lang wrote:
> On Mon, Sep 14, 2020 at 02:30:53PM +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.
> > 
> > Signed-off-by: Chandan Babu R <chandanrlinux@gmail.com>
> > ---
> >  tests/xfs/260     | 52 +++++++++++++++++++++++++++++++++++++++++++++++
> >  tests/xfs/260.out |  2 ++
> >  tests/xfs/group   |  1 +
> >  3 files changed, 55 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..5fc1a5fc
> > --- /dev/null
> > +++ b/tests/xfs/260
> > @@ -0,0 +1,52 @@
> > +#! /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.

Please state explicitly that this is a regression test for "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 $seqres.full
> > +
> > +# real QA test starts here
> > +
> > +# Modify as appropriate.
>      ^^^^
> I think this comment line is useless
> 
> > +_supported_fs generic
> > +_supported_os Linux
> > +_require_realtime
> > +
> > +MKFS_OPTIONS="-f -m reflink=0,rmapbt=0 -r rtdev=${SCRATCH_RTDEV},size=10M" \
> > + 	    _mkfs_dev $SCRATCH_DEV >> $seqres.full
> 
> Hmm... if you need a sized rtdev, the _scratch_mkfs really can't help that
> for now. You have to use _mkfs_dev(as you did) or make the helper to support
> rtdev size:)

Does "_scratch_mkfs -r size=10M" not work here?

> I don't know why you need "reflink=0,rmapbt=0", but not old xfsprogs doesn't
> supports this two options, so you might need _scratch_mkfs_xfs_supported()
> to check that. If they're not supported, they won't be enabled either. And
> better to add comment to explain why make sure reflink and rmapbt are disabled.

That's a bug in mkfs.xfs, which should be fixed by "mkfs: fix
reflink/rmap logic w.r.t.  realtime devices and crc=0 support".

> > +_scratch_mount -o rtdev=$SCRATCH_RTDEV
> 
> As I known, xfstests deal with SCRATCH_RTDEV things in common/rc _scratch_options()
> properly, _require_realtime with _scratch_mount are enough, don't need the
> "-o rtdev=$SCRATCH_RTDEV".
> 
> > +
> > +$XFS_GROWFS_PROG $SCRATCH_MNT >> $seqres.full
> > +
> > +_scratch_unmount
> > +
> > +echo "Silence is golden"
> > +
> > +# success, all done
> > +status=0
> > +exit
> > diff --git a/tests/xfs/260.out b/tests/xfs/260.out
> > new file mode 100644
> > index 00000000..18ca517c
> > --- /dev/null
> > +++ b/tests/xfs/260.out
> > @@ -0,0 +1,2 @@
> > +QA output created by 260
> > +Silence is golden
> > diff --git a/tests/xfs/group b/tests/xfs/group
> > index ed0d389e..6f30a2e7 100644
> > --- a/tests/xfs/group
> > +++ b/tests/xfs/group
> > @@ -257,6 +257,7 @@
> >  257 auto quick clone
> >  258 auto quick clone
> >  259 auto quick
> > +260 auto
> 
> Better to add 'growfs' group, and if the case is quick enough, 'quick' is acceptable:)

And maybe the 'realtime' group.

--D

> >  261 auto quick quota
> >  262 dangerous_fuzzers dangerous_scrub dangerous_online_repair
> >  263 auto quick quota
> > -- 
> > 2.28.0
> > 
>