On Wed, Jun 21, 2023 at 9:46 AM Qu Wenruo <wqu@xxxxxxxx> wrote: > > There is a recent regression during v6.4 merge window, that a u32 left > shift overflow can cause problems with large data chunks (over 4G > sized). > > This is the regression test case for it. > > The test case itself would: > > - Create a RAID0 chunk with a single 6G data chunk > This requires at least 6 devices from SCRATCH_DEV_POOL, and each > should be larger than 2G. > > - Fill the fs with 5G data > > - Make sure everything is fine > Including the data csums. > > - Delete half of the data > > - Do a fstrim > This would lead to out-of-boundary trim if the kernel is not patched. > > - Make sure everything is fine again > If not patched, we may have corrupted data due to the bad fstrim > above. > > For now, this test case only checks the behavior for RAID0. > As for RAID10, we need 12 devices, which is out-of-reach for a lot of > test envionrments. > > For RAID56, they would have a different test case, as they don't support > discard inside the RAID56 chunks. > > Signed-off-by: Qu Wenruo <wqu@xxxxxxxx> Looks good now, thanks. Reviewed-by: Filipe Manana <fdmanana@xxxxxxxx> > --- > Changelog: > v2: > - Add requirement for fstrim and batched discard support > - Add some comments on why it's safe as long as each device is larger > than 2G > - Use nodiscard mount option to increase the possibility of > crash/corruption > Newer kernel go with async discard by default and has extra trim cache > to avoid duplicated trim commands. > Disable such discard behavior so that fstrim can always trigger the > bug. > > v3: > - Use the merged fix commit in _fixed_by_kernel_commit > - Add the missing _scratch_dev_pool_put() calls before _fail()/_notrun() > - Fix the spell and grammar of a comment > - Update the error message if we detected a corruption after fstrim > - Use $XFS_IO_PROG instead of direct xfs_io calls > --- > tests/btrfs/292 | 91 +++++++++++++++++++++++++++++++++++++++++++++ > tests/btrfs/292.out | 2 + > 2 files changed, 93 insertions(+) > create mode 100755 tests/btrfs/292 > create mode 100644 tests/btrfs/292.out > > diff --git a/tests/btrfs/292 b/tests/btrfs/292 > new file mode 100755 > index 00000000..32a7c3c5 > --- /dev/null > +++ b/tests/btrfs/292 > @@ -0,0 +1,91 @@ > +#! /bin/bash > +# SPDX-License-Identifier: GPL-2.0 > +# Copyright (C) 2023 SUSE Linux Products GmbH. All Rights Reserved. > +# > +# FS QA Test 292 > +# > +# Test btrfs behavior with large chunks (size beyond 4G) for basic read-write > +# and discard. > +# This test focus on RAID0. > +# > +. ./common/preamble > +_begin_fstest auto raid volume trim > + > +. ./common/filter > + > +# real QA test starts here > + > +# Modify as appropriate. > +_supported_fs btrfs > +_require_scratch_dev_pool 6 > +_require_fstrim > +_fixed_by_kernel_commit a7299a18a179 \ > + "btrfs: fix u32 overflows when left shifting @stripe_nr" > + > +_scratch_dev_pool_get 6 > + > + > +datasize=$((5 * 1024 * 1024 * 1024)) > +filesize=$((8 * 1024 * 1024)) > +nr_files=$(($datasize / $filesize)) > + > +# Make sure each device has at least 2G. > +# Btrfs has a limits on per-device stripe length of 1G. > +# Double that so that we can ensure a RAID0 data chunk with 6G size. > +for i in $SCRATCH_DEV_POOL; do > + devsize=$(blockdev --getsize64 "$i") > + if [ $devsize -lt $((2 * 1024 * 1024 * 1024)) ]; then > + _scratch_dev_pool_put > + _notrun "device $i is too small, need at least 2G" > + fi > +done > + > +_scratch_pool_mkfs -m raid1 -d raid0 >> $seqres.full 2>&1 > + > +# We disable async/sync auto discard, so that btrfs won't try to > +# cache the discard result which can cause unexpected skip for some trim range. > +_scratch_mount -o nodiscard > +_require_batched_discard $SCRATCH_MNT > + > +# Fill the data chunk with 5G data. > +for (( i = 0; i < $nr_files; i++ )); do > + $XFS_IO_PROG -f -c "pwrite -i /dev/urandom 0 $filesize" \ > + $SCRATCH_MNT/file_$i > /dev/null > +done > +sync > +echo "=== With initial 5G data written ===" >> $seqres.full > +$BTRFS_UTIL_PROG filesystem df $SCRATCH_MNT >> $seqres.full > + > +_scratch_unmount > + > +# Make sure we haven't corrupted anything. > +$BTRFS_UTIL_PROG check --check-data-csum $SCRATCH_DEV >> $seqres.full 2>&1 > +if [ $? -ne 0 ]; then > + _scratch_dev_pool_put > + _fail "data corruption detected after initial data filling" > +fi > + > +_scratch_mount -o nodiscard > +# Delete half of the data, and do discard > +rm -rf - "$SCRATCH_MNT/*[02468]" > +sync > +$FSTRIM_PROG $SCRATCH_MNT > + > +echo "=== With 2.5G data trimmed ===" >> $seqres.full > +$BTRFS_UTIL_PROG filesystem df $SCRATCH_MNT >> $seqres.full > +_scratch_unmount > + > +# Make sure fstrim doesn't corrupt anything. > +$BTRFS_UTIL_PROG check --check-data-csum $SCRATCH_DEV >> $seqres.full 2>&1 > +if [ $? -ne 0 ]; then > + _scratch_dev_pool_put > + _fail "data corruption detected after running fstrim" > +fi > + > +_scratch_dev_pool_put > + > +echo "Silence is golden" > + > +# success, all done > +status=0 > +exit > diff --git a/tests/btrfs/292.out b/tests/btrfs/292.out > new file mode 100644 > index 00000000..627309d3 > --- /dev/null > +++ b/tests/btrfs/292.out > @@ -0,0 +1,2 @@ > +QA output created by 292 > +Silence is golden > -- > 2.39.0 >
