| Message ID | 6b66d881e152296eab70acc19991d9a611aefde6.1738792721.git.wqu@suse.com (mailing list archive) |
|---|---|
| State | New |
| Headers | show |
| Series | fstests: btrfs/226: use nodatasum mount option to prevent false alerts | expand |
On 6/2/25 05:58, Qu Wenruo wrote: > [BUG] > With recent kernel patch "btrfs: always fallback to buffered write if the > inode requires checksum", the test case btrfs/226 will fail with the > following error: > > FSTYP -- btrfs > PLATFORM -- Linux/x86_64 btrfs-vm 6.13.0-rc6-custom+ #209 SMP PREEMPT_DYNAMIC Fri Jan 24 17:23:03 ACDT 2025 > MKFS_OPTIONS -- /dev/mapper/test-scratch1 > MOUNT_OPTIONS -- /dev/mapper/test-scratch1 /mnt/scratch > > btrfs/226 1s ... - output mismatch (see /home/adam/xfstests/results//btrfs/226.out.bad) > --- tests/btrfs/226.out 2024-04-12 14:04:03.080000035 +0930 > +++ /home/adam/xfstests/results//btrfs/226.out.bad 2025-02-06 08:23:42.564298585 +1030 > @@ -39,14 +39,11 @@ > Testing write against prealloc extent at eof > wrote 65536/65536 bytes at offset 0 > XXX Bytes, X ops; XX:XX:XX.X (XXX YYY/sec and XXX ops/sec) > -wrote 65536/65536 bytes at offset 65536 > -XXX Bytes, X ops; XX:XX:XX.X (XXX YYY/sec and XXX ops/sec) > +pwrite: Resource temporarily unavailable > File after write: > ... > (Run 'diff -u /home/adam/xfstests/tests/btrfs/226.out /home/adam/xfstests/results//btrfs/226.out.bad' to see the entire diff) > Ran: btrfs/226 > Failures: btrfs/226 > Failed 1 of 1 tests > > [CAUSE] > That kernel patch makes btrfs to always fallback to buffered IO if the > target inode requires data checksum. > > This is to avoid more deadly problems of mismatched data checksum. > > But this also means, for inodes with data checksum, RWF_NOWAIT will > always fail, because we will wait writing back the page cache, thus > breaking the RWF_NOWAIT requirement. > > [FIX] > Update the test case to utilize nodatasum mount option, so that the > direct-IO will not fallback to buffered ones unconditionally. > > Reported-by: Filipe Manana <fdmanana@kernel.org> > Signed-off-by: Qu Wenruo <wqu@suse.com> > --- > tests/btrfs/226 | 7 ++++++- > 1 file changed, 6 insertions(+), 1 deletion(-) > > diff --git a/tests/btrfs/226 b/tests/btrfs/226 > index 70275d0aa2d8..359813c4f394 100755 > --- a/tests/btrfs/226 > +++ b/tests/btrfs/226 > @@ -21,7 +21,12 @@ _require_xfs_io_command falloc -k > _require_xfs_io_command fpunch > > _scratch_mkfs >>$seqres.full 2>&1 > -_scratch_mount > + > +# This test involves RWF_NOWAIT direct IOs, but for inodes with data checksum, > +# btrfs will fall back to buffered IO unconditionally to prevent data checksum > +# mimsatch, and that will break RWF_NOWAIT with -EAGAIN. > +# So here we have to go with nodatasum mount option. > +_scratch_mount -o nodatasum > Looks good. Reviewed-by: Anand Jain <anand.jain@oracle.com> Thx. > # Test a write against COW file/extent - should fail with -EAGAIN. Disable the > # NOCOW attribute of the file just in case MOUNT_OPTIONS has "-o nodatacow".
On Wed, Feb 5, 2025 at 9:59 PM Qu Wenruo <wqu@suse.com> wrote: > > [BUG] > With recent kernel patch "btrfs: always fallback to buffered write if the > inode requires checksum", the test case btrfs/226 will fail with the > following error: > > FSTYP -- btrfs > PLATFORM -- Linux/x86_64 btrfs-vm 6.13.0-rc6-custom+ #209 SMP PREEMPT_DYNAMIC Fri Jan 24 17:23:03 ACDT 2025 > MKFS_OPTIONS -- /dev/mapper/test-scratch1 > MOUNT_OPTIONS -- /dev/mapper/test-scratch1 /mnt/scratch > > btrfs/226 1s ... - output mismatch (see /home/adam/xfstests/results//btrfs/226.out.bad) > --- tests/btrfs/226.out 2024-04-12 14:04:03.080000035 +0930 > +++ /home/adam/xfstests/results//btrfs/226.out.bad 2025-02-06 08:23:42.564298585 +1030 > @@ -39,14 +39,11 @@ > Testing write against prealloc extent at eof > wrote 65536/65536 bytes at offset 0 > XXX Bytes, X ops; XX:XX:XX.X (XXX YYY/sec and XXX ops/sec) > -wrote 65536/65536 bytes at offset 65536 > -XXX Bytes, X ops; XX:XX:XX.X (XXX YYY/sec and XXX ops/sec) > +pwrite: Resource temporarily unavailable > File after write: > ... > (Run 'diff -u /home/adam/xfstests/tests/btrfs/226.out /home/adam/xfstests/results//btrfs/226.out.bad' to see the entire diff) > Ran: btrfs/226 > Failures: btrfs/226 > Failed 1 of 1 tests > > [CAUSE] > That kernel patch makes btrfs to always fallback to buffered IO if the > target inode requires data checksum. > > This is to avoid more deadly problems of mismatched data checksum. > > But this also means, for inodes with data checksum, RWF_NOWAIT will > always fail, because we will wait writing back the page cache, thus > breaking the RWF_NOWAIT requirement. > > [FIX] > Update the test case to utilize nodatasum mount option, so that the > direct-IO will not fallback to buffered ones unconditionally. > > Reported-by: Filipe Manana <fdmanana@kernel.org> > Signed-off-by: Qu Wenruo <wqu@suse.com> > --- > tests/btrfs/226 | 7 ++++++- > 1 file changed, 6 insertions(+), 1 deletion(-) > > diff --git a/tests/btrfs/226 b/tests/btrfs/226 > index 70275d0aa2d8..359813c4f394 100755 > --- a/tests/btrfs/226 > +++ b/tests/btrfs/226 > @@ -21,7 +21,12 @@ _require_xfs_io_command falloc -k > _require_xfs_io_command fpunch > > _scratch_mkfs >>$seqres.full 2>&1 > -_scratch_mount > + > +# This test involves RWF_NOWAIT direct IOs, but for inodes with data checksum, involves -> exercises > +# btrfs will fall back to buffered IO unconditionally to prevent data checksum > +# mimsatch, and that will break RWF_NOWAIT with -EAGAIN. mimsatch -> mismatch > +# So here we have to go with nodatasum mount option. The whole text could be shorter and clear: # RWF_NOWAIT only works with direct IO, which requires an inode with nodatasum (otherwise it falls back to buffered IO). Otherwise it looks fine, so: Reviewed-by: Filipe Manana <fdmanana@suse.com> Thanks. > +_scratch_mount -o nodatasum > > # Test a write against COW file/extent - should fail with -EAGAIN. Disable the > # NOCOW attribute of the file just in case MOUNT_OPTIONS has "-o nodatacow". > -- > 2.48.1 >
On 6/2/25 20:10, Filipe Manana wrote: > On Wed, Feb 5, 2025 at 9:59 PM Qu Wenruo <wqu@suse.com> wrote: >> >> [BUG] >> With recent kernel patch "btrfs: always fallback to buffered write if the >> inode requires checksum", the test case btrfs/226 will fail with the >> following error: >> >> FSTYP -- btrfs >> PLATFORM -- Linux/x86_64 btrfs-vm 6.13.0-rc6-custom+ #209 SMP PREEMPT_DYNAMIC Fri Jan 24 17:23:03 ACDT 2025 >> MKFS_OPTIONS -- /dev/mapper/test-scratch1 >> MOUNT_OPTIONS -- /dev/mapper/test-scratch1 /mnt/scratch >> >> btrfs/226 1s ... - output mismatch (see /home/adam/xfstests/results//btrfs/226.out.bad) >> --- tests/btrfs/226.out 2024-04-12 14:04:03.080000035 +0930 >> +++ /home/adam/xfstests/results//btrfs/226.out.bad 2025-02-06 08:23:42.564298585 +1030 >> @@ -39,14 +39,11 @@ >> Testing write against prealloc extent at eof >> wrote 65536/65536 bytes at offset 0 >> XXX Bytes, X ops; XX:XX:XX.X (XXX YYY/sec and XXX ops/sec) >> -wrote 65536/65536 bytes at offset 65536 >> -XXX Bytes, X ops; XX:XX:XX.X (XXX YYY/sec and XXX ops/sec) >> +pwrite: Resource temporarily unavailable >> File after write: >> ... >> (Run 'diff -u /home/adam/xfstests/tests/btrfs/226.out /home/adam/xfstests/results//btrfs/226.out.bad' to see the entire diff) >> Ran: btrfs/226 >> Failures: btrfs/226 >> Failed 1 of 1 tests >> >> [CAUSE] >> That kernel patch makes btrfs to always fallback to buffered IO if the >> target inode requires data checksum. >> >> This is to avoid more deadly problems of mismatched data checksum. >> >> But this also means, for inodes with data checksum, RWF_NOWAIT will >> always fail, because we will wait writing back the page cache, thus >> breaking the RWF_NOWAIT requirement. >> >> [FIX] >> Update the test case to utilize nodatasum mount option, so that the >> direct-IO will not fallback to buffered ones unconditionally. >> >> Reported-by: Filipe Manana <fdmanana@kernel.org> >> Signed-off-by: Qu Wenruo <wqu@suse.com> >> --- >> tests/btrfs/226 | 7 ++++++- >> 1 file changed, 6 insertions(+), 1 deletion(-) >> >> diff --git a/tests/btrfs/226 b/tests/btrfs/226 >> index 70275d0aa2d8..359813c4f394 100755 >> --- a/tests/btrfs/226 >> +++ b/tests/btrfs/226 >> @@ -21,7 +21,12 @@ _require_xfs_io_command falloc -k >> _require_xfs_io_command fpunch >> >> _scratch_mkfs >>$seqres.full 2>&1 >> -_scratch_mount >> + >> +# This test involves RWF_NOWAIT direct IOs, but for inodes with data checksum, > > involves -> exercises > >> +# btrfs will fall back to buffered IO unconditionally to prevent data checksum >> +# mimsatch, and that will break RWF_NOWAIT with -EAGAIN. > > mimsatch -> mismatch > >> +# So here we have to go with nodatasum mount option. > > The whole text could be shorter and clear: > > # RWF_NOWAIT only works with direct IO, which requires an inode with > nodatasum (otherwise it falls back to buffered IO). > > Otherwise it looks fine, so: > > Reviewed-by: Filipe Manana <fdmanana@suse.com> > Fixed. Applied to for-next at https://github.com/asj/fstests.git Thx. > Thanks. > >> +_scratch_mount -o nodatasum >> >> # Test a write against COW file/extent - should fail with -EAGAIN. Disable the >> # NOCOW attribute of the file just in case MOUNT_OPTIONS has "-o nodatacow". >> -- >> 2.48.1 >>
diff --git a/tests/btrfs/226 b/tests/btrfs/226 index 70275d0aa2d8..359813c4f394 100755 --- a/tests/btrfs/226 +++ b/tests/btrfs/226 @@ -21,7 +21,12 @@ _require_xfs_io_command falloc -k _require_xfs_io_command fpunch _scratch_mkfs >>$seqres.full 2>&1 -_scratch_mount + +# This test involves RWF_NOWAIT direct IOs, but for inodes with data checksum, +# btrfs will fall back to buffered IO unconditionally to prevent data checksum +# mimsatch, and that will break RWF_NOWAIT with -EAGAIN. +# So here we have to go with nodatasum mount option. +_scratch_mount -o nodatasum # Test a write against COW file/extent - should fail with -EAGAIN. Disable the # NOCOW attribute of the file just in case MOUNT_OPTIONS has "-o nodatacow".
[BUG] With recent kernel patch "btrfs: always fallback to buffered write if the inode requires checksum", the test case btrfs/226 will fail with the following error: FSTYP -- btrfs PLATFORM -- Linux/x86_64 btrfs-vm 6.13.0-rc6-custom+ #209 SMP PREEMPT_DYNAMIC Fri Jan 24 17:23:03 ACDT 2025 MKFS_OPTIONS -- /dev/mapper/test-scratch1 MOUNT_OPTIONS -- /dev/mapper/test-scratch1 /mnt/scratch btrfs/226 1s ... - output mismatch (see /home/adam/xfstests/results//btrfs/226.out.bad) --- tests/btrfs/226.out 2024-04-12 14:04:03.080000035 +0930 +++ /home/adam/xfstests/results//btrfs/226.out.bad 2025-02-06 08:23:42.564298585 +1030 @@ -39,14 +39,11 @@ Testing write against prealloc extent at eof wrote 65536/65536 bytes at offset 0 XXX Bytes, X ops; XX:XX:XX.X (XXX YYY/sec and XXX ops/sec) -wrote 65536/65536 bytes at offset 65536 -XXX Bytes, X ops; XX:XX:XX.X (XXX YYY/sec and XXX ops/sec) +pwrite: Resource temporarily unavailable File after write: ... (Run 'diff -u /home/adam/xfstests/tests/btrfs/226.out /home/adam/xfstests/results//btrfs/226.out.bad' to see the entire diff) Ran: btrfs/226 Failures: btrfs/226 Failed 1 of 1 tests [CAUSE] That kernel patch makes btrfs to always fallback to buffered IO if the target inode requires data checksum. This is to avoid more deadly problems of mismatched data checksum. But this also means, for inodes with data checksum, RWF_NOWAIT will always fail, because we will wait writing back the page cache, thus breaking the RWF_NOWAIT requirement. [FIX] Update the test case to utilize nodatasum mount option, so that the direct-IO will not fallback to buffered ones unconditionally. Reported-by: Filipe Manana <fdmanana@kernel.org> Signed-off-by: Qu Wenruo <wqu@suse.com> --- tests/btrfs/226 | 7 ++++++- 1 file changed, 6 insertions(+), 1 deletion(-)