| Message ID | 20230621070744.199846-1-wqu@suse.com (mailing list archive) |
|---|---|
| State | New, archived |
| Headers | show |
| Series | [v2] btrfs: add test case to verify the behavior with large RAID0 data chunks | expand |
On Wed, Jun 21, 2023 at 8:24 AM Qu Wenruo <wqu@suse.com> 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@suse.com> > --- > 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. > --- > tests/btrfs/292 | 87 +++++++++++++++++++++++++++++++++++++++++++++ > tests/btrfs/292.out | 2 ++ > 2 files changed, 89 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..c7b9fe92 > --- /dev/null > +++ b/tests/btrfs/292 > @@ -0,0 +1,87 @@ > +#! /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 xxxxxxxxxxxx \ > + "btrfs: fix u32 overflows when left shifting @stripe_nr" The patch was merged into Linus' tree, so please put the commit id: https://git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux.git/commit/?id=a7299a18a179a9713651fce9ad00972a633c14a9 I think you missed this, because you also sent a v3 of the patch yet v2 was sent to Linus and pulled before you sent it (as well as this test case). > + > +_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 > + _notrun "device $i is too small, need at least 2G" here need a _scratch_dev_pool_put before _notrun > + 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 -f -c "pwrite -i /dev/urandom 0 $filesize" $SCRATCH_MNT/file_$i > /dev/null Use $XFS_IO_PROG instead of xfs_io. > +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 [ $? -ne 0 ]; then > + _fail "data corruption detected after initial data filling" here need a _scratch_dev_pool_put before calling _fail > +fi > + > +_scratch_mount -o nodiscard > +# Delete half of the data, and do discard > +rm -rf - "$SCRATCH_MNT/*[02468]" > +sync > +$FSTRIM_PROG $SCRATCH_MNT > + > +echo "=== With 2.5G data trimmed ===" >> $seqres.full > +$BTRFS_UTIL_PROG filesystem df $SCRATCH_MNT >> $seqres.full > +_scratch_unmount > + > +# Make sure fstrim didn't corrupte anything. corrupte -> corrupt didn't -> doesn't > +$BTRFS_UTIL_PROG check --check-data-csum $SCRATCH_DEV >> $seqres.full 2>&1 > +if [ $? -ne 0 ]; then > + _fail "data corruption detected after initial data filling" here need a _scratch_dev_pool_put before calling _fail Also, the message is pasted from the previous check, so here it should be something like: "data corruption detected after running fsstrim" Thanks. > +fi > + > +_scratch_dev_pool_put > + > +echo "Silence is golden" > + > +# success, all done > +status=0 > +exit > diff --git a/tests/btrfs/292.out b/tests/btrfs/292.out > new file mode 100644 > index 00000000..627309d3 > --- /dev/null > +++ b/tests/btrfs/292.out > @@ -0,0 +1,2 @@ > +QA output created by 292 > +Silence is golden > -- > 2.39.0 >
diff --git a/tests/btrfs/292 b/tests/btrfs/292 new file mode 100755 index 00000000..c7b9fe92 --- /dev/null +++ b/tests/btrfs/292 @@ -0,0 +1,87 @@ +#! /bin/bash +# SPDX-License-Identifier: GPL-2.0 +# Copyright (C) 2023 SUSE Linux Products GmbH. All Rights Reserved. +# +# FS QA Test 292 +# +# Test btrfs behavior with large chunks (size beyond 4G) for basic read-write +# and discard. +# This test focus on RAID0. +# +. ./common/preamble +_begin_fstest auto raid volume trim + +. ./common/filter + +# real QA test starts here + +# Modify as appropriate. +_supported_fs btrfs +_require_scratch_dev_pool 6 +_require_fstrim +_fixed_by_kernel_commit xxxxxxxxxxxx \ + "btrfs: fix u32 overflows when left shifting @stripe_nr" + +_scratch_dev_pool_get 6 + + +datasize=$((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 + _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 -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 [ $? -ne 0 ]; then + _fail "data corruption detected after initial data filling" +fi + +_scratch_mount -o nodiscard +# Delete half of the data, and do discard +rm -rf - "$SCRATCH_MNT/*[02468]" +sync +$FSTRIM_PROG $SCRATCH_MNT + +echo "=== With 2.5G data trimmed ===" >> $seqres.full +$BTRFS_UTIL_PROG filesystem df $SCRATCH_MNT >> $seqres.full +_scratch_unmount + +# Make sure fstrim didn't corrupte anything. +$BTRFS_UTIL_PROG check --check-data-csum $SCRATCH_DEV >> $seqres.full 2>&1 +if [ $? -ne 0 ]; then + _fail "data corruption detected after initial data filling" +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
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@suse.com> --- 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. --- tests/btrfs/292 | 87 +++++++++++++++++++++++++++++++++++++++++++++ tests/btrfs/292.out | 2 ++ 2 files changed, 89 insertions(+) create mode 100755 tests/btrfs/292 create mode 100644 tests/btrfs/292.out