Re: mkfs.xfs "concurrency" change concerns

[Shin'ichiro Kawasaki <shinichiro.kawasaki@wdc.com>]

On Jun 15, 2026 / 22:24, Christoph Hellwig wrote:
> On Mon, Jun 15, 2026 at 08:40:48AM -0700, Darrick J. Wong wrote:
> > Lukas Herbolt posted some fixes for a few of the fstests to inject
> > concurrency=0 into mkfs.  IIRC there weren't any changes for 078, but
> > you might ask him if he has more bugs to address.
> 
> Shin'ichiro, can you check if inserting concurrency=0 fixes xfs/078
> and xfs/216 for you?  (and IIRC xfs/217 which lingers in some reports).

I tried mkfs.xfs options "-d concurrency=0 -l concurrency=0 -r concurrency=0",
specifying all three options together, but it did not avoid the failures at
xfs/078 and xfs/216 in my test environments (I checked my recent test run
records, but did not find xfs/217 failure).

Just FYI, here's my command line logs. nullb0 and nullb1 are 8GiB memory backed
null_blk devices. I also tried each of "-d concurrency=0", "-l concurrency=0"
and "-r concurrency=0" seperately, and observed the same failures. I used the
kernel at xfs/for-next on Jun/12 and fstests tag v2026.05.17. The fstests
alraday has the commit by Lukas ffc8bad17e5b ("xfs/21{6,7} Use default -l
concurrency=0 on mkfs.xfs that supports it").


$ cat ./local.config
export TEST_DIR=/var/kts/test
export TEST_DEV="/dev/nullb0"
export KEEP_DMESG=yes
export FSTYP=xfs
export MKFS_OPTIONS="-d concurrency=0 -l concurrency=0 -r concurrency=0"
export SCRATCH_MNT=/var/kts/scratch
export SCRATCH_DEV="/dev/nullb1"
export FSX_AVOID=-a
$ sudo mkfs.xfs -f -d concurrency=0 -l concurrency=0 -r concurrency=0 /dev/nullb0
meta-data=/dev/nullb0            isize=512    agcount=4, agsize=524288 blks
         =                       sectsz=512   attr=2, projid32bit=1
         =                       crc=1        finobt=1, sparse=1, rmapbt=1
         =                       reflink=1    bigtime=1 inobtcount=1 nrext64=1
         =                       exchange=1   metadir=0
data     =                       bsize=4096   blocks=2097152, imaxpct=25
         =                       sunit=0      swidth=0 blks
naming   =version 2              bsize=4096   ascii-ci=0, ftype=1, parent=1
log      =internal log           bsize=4096   blocks=16384, version=2
         =                       sectsz=512   sunit=0 blks, lazy-count=1
realtime =none                   extsz=4096   blocks=0, rtextents=0
         =                       rgcount=0    rgsize=0 extents
         =                       zoned=0      start=0 reserved=0
$ sudo ./check xfs/078 xfs/216
FSTYP         -- xfs (non-debug)
PLATFORM      -- Linux/x86_64 redsun71q 7.1.0-rc4-kts-xfs-g804826eac53+ #1 SMP PREEMPT_DYNAMIC Mon Jun 15 09:31:13 JST 2026
MKFS_OPTIONS  -- -f -d concurrency=0 -l concurrency=0 -r concurrency=0 /dev/nullb1
MOUNT_OPTIONS -- -o context=system_u:object_r:root_t:s0 /dev/nullb1 /var/kts/scratch

xfs/078            - output mismatch (see /home/shin/kts/kernel-test-suite/src/xfstests/results//xfs/078.out.bad)
    --- tests/xfs/078.out	2026-06-15 09:49:28.616774560 +0900
    +++ /home/shin/kts/kernel-test-suite/src/xfstests/results//xfs/078.out.bad	2026-06-17 10:19:09.364881845 +0900
    @@ -68,8 +68,8 @@
     wrote 4096/4096 bytes at offset 2684354560000
     *** mount loop filesystem
     *** grow loop filesystem
    -xfs_growfs --BlockSize=4096 --Blocks=268435456
    -data blocks changed from 268435456 to 655360001
    +xfs_growfs --BlockSize=4096 --Blocks=268435440
    +data blocks changed from 268435440 to 655360001
    ...
    (Run 'diff -u /home/shin/kts/kernel-test-suite/src/xfstests/tests/xfs/078.out /home/shin/kts/kernel-test-suite/src/xfstests/results//xfs/078.out.bad'  to see the entire diff)
xfs/216            - output mismatch (see /home/shin/kts/kernel-test-suite/src/xfstests/results//xfs/216.out.bad)
    --- tests/xfs/216.out	2026-06-15 09:49:28.794774318 +0900
    +++ /home/shin/kts/kernel-test-suite/src/xfstests/results//xfs/216.out.bad	2026-06-17 10:19:17.643595048 +0900
    @@ -7,4 +7,4 @@
     fssize=32g log      =internal log           bsize=4096   blocks=16384, version=2
     fssize=64g log      =internal log           bsize=4096   blocks=16384, version=2
     fssize=128g log      =internal log           bsize=4096   blocks=16384, version=2
    -fssize=256g log      =internal log           bsize=4096   blocks=32768, version=2
    +fssize=256g log      =internal log           bsize=4096   blocks=32767, version=2
    ...
    (Run 'diff -u /home/shin/kts/kernel-test-suite/src/xfstests/tests/xfs/216.out /home/shin/kts/kernel-test-suite/src/xfstests/results//xfs/216.out.bad'  to see the entire diff)
Ran: xfs/078 xfs/216
Failures: xfs/078 xfs/216
Failed 2 of 2 tests