Re: [PATCH v2] generic: test replacing a xattr with a larger value

[Zorro Lang <zlang@kernel.org>]

On Sat, Sep 26, 2026 at 07:19:46PM +0100, Filipe Manana wrote:
> On Sat, Sep 26, 2026 at 6:58 AM Qu Wenruo <wqu@suse.com> wrote:
> >
> >
> >
> > 在 2026/9/26 02:46, fdmanana@kernel.org 写道:
> > > From: Filipe Manana <fdmanana@suse.com>
> > >
> > > Test that replacing a xattr's value with a larger value works. This is a
> > > test that exercises a specific scenario on btrfs where two xattrs are
> > > stored in the same item, and for that to happen their names must result
> > > in the same crc32c hash.
> > >
> > > This was recently fixed by the following patch:
> > >
> > >    "btrfs: fix xattr replace when multiple xattrs are packed in the same item"
> > >
> > > Signed-off-by: Filipe Manana <fdmanana@suse.com>
> >
> > Missing the "---" line, which makes b4 include the digest and changelog.
> 
> Looks like I may have accidentally deleted it.
> Maybe Zorro can add it when he picks the patch.

Sure, done!

> 
> Thanks.
> 
> >
> > Otherwise looks good to me.
> >
> > Reviewed-by: Qu Wenruo <wqu@suse.com>
> >
> > Thanks,
> > Qu
> >
> > >
> > > V2: Fix missing _ on _fixed_by_fs_commit call.
> > >
> > >   tests/generic/806     | 43 +++++++++++++++++++++++++++++++++++++++++++
> > >   tests/generic/806.out | 11 +++++++++++
> > >   2 files changed, 54 insertions(+)
> > >   create mode 100755 tests/generic/806
> > >   create mode 100644 tests/generic/806.out
> > >
> > > diff --git a/tests/generic/806 b/tests/generic/806
> > > new file mode 100755
> > > index 00000000..1fcf0145
> > > --- /dev/null
> > > +++ b/tests/generic/806
> > > @@ -0,0 +1,43 @@
> > > +#! /bin/bash
> > > +# SPDX-License-Identifier: GPL-2.0
> > > +# Copyright (c) 2026 SUSE S.A.  All Rights Reserved.
> > > +#
> > > +# FS QA Test 806
> > > +#
> > > +# Test replacing a xattr's value with a larger value.
> > > +#
> > > +. ./common/preamble
> > > +_begin_fstest auto quick metadata attr
> > > +
> > > +. ./common/filter
> > > +. ./common/attr
> > > +
> > > +_require_scratch
> > > +_require_attrs
> > > +
> > > +_fixed_by_fs_commit btrfs xxxxxxxxxxxx \
> > > +   "btrfs: fix xattr replace when multiple xattrs are packed in the same item"
> > > +
> > > +_scratch_mkfs >>$seqres.full 2>&1 || _fail "mkfs failed"
> > > +_scratch_mount
> > > +
> > > +touch $SCRATCH_MNT/testfile
> > > +
> > > +# Add two xattrs that, on btrfs, have the same hash (crc32c) for their name
> > > +# and therefore are packed into the same btrfs_dir_item.
> > > +$SETFATTR_PROG -n user.foobar -v 123 $SCRATCH_MNT/testfile
> > > +$SETFATTR_PROG -n user.WvG1c1Td -v qwerty $SCRATCH_MNT/testfile
> > > +
> > > +# Verify the xattrs are present.
> > > +echo "xattrs before:"
> > > +_getfattr --absolute-names --dump $SCRATCH_MNT/testfile | _filter_scratch
> > > +
> > > +# Now replace the value of the foobar xattr with a significantly larger value.
> > > +$SETFATTR_PROG -n user.foobar -v abcdefghijklmnopqrstuvwxyz $SCRATCH_MNT/testfile
> > > +
> > > +# Check the xattrs have the expected values.
> > > +echo "xattrs after:"
> > > +_getfattr --absolute-names --dump $SCRATCH_MNT/testfile | _filter_scratch
> > > +
> > > +# success, all done
> > > +_exit 0
> > > diff --git a/tests/generic/806.out b/tests/generic/806.out
> > > new file mode 100644
> > > index 00000000..620a953e
> > > --- /dev/null
> > > +++ b/tests/generic/806.out
> > > @@ -0,0 +1,11 @@
> > > +QA output created by 806
> > > +xattrs before:
> > > +# file: SCRATCH_MNT/testfile
> > > +user.WvG1c1Td="qwerty"
> > > +user.foobar="123"
> > > +
> > > +xattrs after:
> > > +# file: SCRATCH_MNT/testfile
> > > +user.WvG1c1Td="qwerty"
> > > +user.foobar="abcdefghijklmnopqrstuvwxyz"
> > > +
> >