Re: [vbabka:b4/sheaves-for-all-rebased] [slab] 9b0317d1c2: xfstests.generic.629.fail

hi, Vlastimil Babka,

On Mon, Jan 12, 2026 at 09:34:20AM +0100, Vlastimil Babka wrote:
> On 1/12/26 03:54, kernel test robot wrote:
> > 
> > 
> > Hello,
> > 
> > kernel test robot noticed "xfstests.generic.629.fail" on:
> > 
> > commit: 9b0317d1c2ed590d69d39eba701cd3eb082ecc31 ("slab: remove cpu (partial) slabs usage from allocation paths")
> > https://git.kernel.org/cgit/linux/kernel/git/vbabka/linux.git b4/sheaves-for-all-rebased
> > 
> > in testcase: xfstests
> > version: xfstests-x86_64-df16c93a-1_20260105
> > with following parameters:
> > 
> > 	disk: 4HDD
> > 	fs: btrfs
> > 	test: generic-629
> > 
> > 
> > 
> > config: x86_64-rhel-9.4-func
> > compiler: gcc-14
> > test machine: 4 threads Intel(R) Core(TM) i5-6500 CPU @ 3.20GHz (Skylake) with 32G memory
> > 
> > (please refer to attached dmesg/kmsg for entire log/backtrace)
> > 
> > 
> > 
> > If you fix the issue in a separate patch/commit (i.e. not just a new version of
> > the same patch/commit), kindly add following tags
> > | Reported-by: kernel test robot <[email protected]>
> > | Closes: https://lore.kernel.org/oe-lkp/[email protected]
> > 
> > 2026-01-11 11:59:36 cd /lkp/benchmarks/xfstests
> > 2026-01-11 11:59:37 export TEST_DIR=/fs/sdb1
> > 2026-01-11 11:59:37 export TEST_DEV=/dev/sdb1
> > 2026-01-11 11:59:37 export FSTYP=btrfs
> > 2026-01-11 11:59:37 export SCRATCH_MNT=/fs/scratch
> > 2026-01-11 11:59:37 mkdir /fs/scratch -p
> > 2026-01-11 11:59:37 export SCRATCH_DEV_POOL="/dev/sdb2 /dev/sdb3 /dev/sdb4"
> > 2026-01-11 11:59:37 echo generic/629
> > 2026-01-11 11:59:37 ./check generic/629
> > FSTYP         -- btrfs
> > PLATFORM      -- Linux/x86_64 lkp-skl-d03 6.19.0-rc1-00010-g9b0317d1c2ed #1 SMP PREEMPT_DYNAMIC Sun Jan 11 19:50:05 CST 2026
> > MKFS_OPTIONS  -- /dev/sdb2
> > MOUNT_OPTIONS -- /dev/sdb2 /fs/scratch
> > 
> > generic/629        _check_dmesg: something found in dmesg (see /lkp/benchmarks/xfstests/results//generic/629.dmesg)
> 
> Hm I didn't notice anything suspicious in dmesg.xz - any idea what this
> refers to?

sorry, our bot has a bug to capture serial output fully in a consistent way in
this case.
attached one which includes more information.


[   60.803765][ T5096] ------------[ cut here ]------------
[   60.809075][ T5096] kmem_cache_destroy bio-240: Slab cache still has objects when called from bioset_exit+0x307/0x490
[   60.809083][ T5096] WARNING: mm/slab_common.c:562 at kmem_cache_destroy+0x14e/0x170, CPU#1: dmsetup/5096
[   60.829092][ T5096] Modules linked in: dm_mod binfmt_misc snd_hda_codec_intelhdmi snd_hda_codec_hdmi snd_ctl_led snd_hda_codec_alc269 snd_hda_scodec_component snd_hda_codec_realtek_lib snd_hda_codec_generic btrfs blake2b libblake2b xor intel_rapl_msr intel_rapl_common zstd_compress raid6_pq x86_pkg_temp_thermal intel_powerclamp coretemp i915 sd_mod sg snd_hda_intel snd_soc_avs kvm_intel intel_gtt snd_soc_hda_codec platform_profile snd_hda_ext_core drm_buddy kvm dell_wmi snd_hda_codec ttm snd_hda_core snd_intel_dspcfg irqbypass snd_intel_sdw_acpi ghash_clmulni_intel dell_smbios rfkill snd_hwdep rapl dcdbas drm_display_helper mei_wdt snd_soc_core ahci snd_compress dell_wmi_descriptor intel_cstate wmi_bmof snd_pcm dell_smm_hwmon sparse_keymap cec libahci mei_me snd_timer intel_uncore mei drm_client_lib i2c_i801 i2c_smbus snd libata drm_kms_helper pcspkr soundcore intel_pch_thermal intel_pmc_core video pmt_telemetry pmt_discovery wmi pmt_class intel_pmc_ssram_telemetry intel_vsec acpi_pad fuse drm nfnetlink
[   60.917640][ T5096] CPU: 1 UID: 0 PID: 5096 Comm: dmsetup Tainted: G S        I         6.19.0-rc1-00010-g9b0317d1c2ed #1 PREEMPT(voluntary) 
[   60.930326][ T5096] Tainted: [S]=CPU_OUT_OF_SPEC, [I]=FIRMWARE_WORKAROUND
[   60.937097][ T5096] Hardware name: Dell Inc. OptiPlex 7040/0Y7WYT, BIOS 1.1.1 10/07/2015
[   60.945162][ T5096] RIP: 0010:kmem_cache_destroy+0x15e/0x170
[   60.950802][ T5096] Code: 5b 5d e9 85 47 11 00 c3 cc cc cc cc e8 1b 1e a2 ff eb 9b 48 8d 3d 42 87 64 04 48 8b 53 68 48 8b 4c 24 10 48 c7 c6 70 09 3e 84 <67> 48 0f b9 3a e9 18 ff ff ff 0f 1f 84 00 00 00 00 00 90 90 90 90
[   60.970186][ T5096] RSP: 0018:ffffc90004027818 EFLAGS: 00010202
[   60.976081][ T5096] RAX: 0000000000000001 RBX: ffff888214f277c0 RCX: ffffffff8271f597
[   60.983898][ T5096] RDX: ffff888111b2d760 RSI: ffffffff843e0970 RDI: ffffffff8633a210
[   60.991688][ T5096] RBP: 0000000000000001 R08: 0000000000000000 R09: ffffed10fbd98579
[   60.999481][ T5096] R10: ffff8887decc2bcf R11: 0000000000002710 R12: 00000000000000f0
[   61.007288][ T5096] R13: ffff888214f277c0 R14: ffff8881e393c0b8 R15: ffff8881e393c050
[   61.015110][ T5096] FS:  00007f8dbc0b7d80(0000) GS:ffff888857975000(0000) knlGS:0000000000000000
[   61.023865][ T5096] CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
[   61.030275][ T5096] CR2: 00007f637994641c CR3: 0000000159b52006 CR4: 00000000003726f0
[   61.038065][ T5096] Call Trace:
[   61.041194][ T5096]  <TASK>
[   61.043988][ T5096]  bioset_exit+0x307/0x490
[   61.048245][ T5096]  cleanup_mapped_device+0x8b/0x480 [dm_mod]
[   61.054102][ T5096]  __dm_destroy+0x322/0x550 [dm_mod]
[   61.059258][ T5096]  ? __pfx_dev_remove+0x10/0x10 [dm_mod]
[   61.064755][ T5096]  dev_remove+0x231/0x300 [dm_mod]
[   61.069715][ T5096]  ctl_ioctl+0x380/0x710 [dm_mod]
[   61.074590][ T5096]  ? __pfx_ctl_ioctl+0x10/0x10 [dm_mod]
[   61.079981][ T5096]  ? _raw_spin_lock+0x80/0xe0
[   61.084508][ T5096]  ? fdget+0x54/0x3b0
[   61.088325][ T5096]  ? kmem_cache_free+0x294/0x510
[   61.093097][ T5096]  dm_ctl_ioctl+0xa/0x20 [dm_mod]
[   61.097970][ T5096]  __x64_sys_ioctl+0x135/0x1c0
[   61.102568][ T5096]  do_syscall_64+0x7b/0x6c0
[   61.106933][ T5096]  ? do_semtimedop+0x228/0x2a0
[   61.111533][ T5096]  ? __pfx_ksys_semctl+0x10/0x10
[   61.117340][ T5096]  ? __pfx_ksys_semctl+0x10/0x10
[   61.123145][ T5096]  ? __virt_addr_valid+0xc4/0x200
[   61.128016][ T5096]  ? rcu_segcblist_enqueue+0x1d/0xe0
[   61.133159][ T5096]  ? __call_rcu_common+0x341/0x950
[   61.139137][ T5096]  ? kasan_unpoison+0x40/0x70
[   61.143648][ T5096]  ? __pfx___call_rcu_common+0x10/0x10
[   61.149973][ T5096]  ? __kasan_slab_alloc+0x2f/0x70
[   61.154838][ T5096]  ? do_syscall_64+0xb2/0x6c0
[   61.159353][ T5096]  ? kmem_cache_free+0x2a7/0x510
[   61.164142][ T5096]  ? fput_close_sync+0xd8/0x190
[   61.168831][ T5096]  ? fput_close_sync+0xd8/0x190
[   61.173537][ T5096]  ? __x64_sys_semtimedop+0x153/0x1a0
[   61.178749][ T5096]  ? __pfx___x64_sys_semtimedop+0x10/0x10
[   61.184308][ T5096]  ? __x64_sys_close+0x79/0xd0
[   61.188919][ T5096]  ? do_syscall_64+0xb2/0x6c0
[   61.193429][ T5096]  ? do_syscall_64+0xb2/0x6c0
[   61.197943][ T5096]  ? do_syscall_64+0xb2/0x6c0
[   61.202453][ T5096]  ? irqentry_exit+0x76/0x4d0
[   61.206963][ T5096]  entry_SYSCALL_64_after_hwframe+0x76/0x7e
[   61.212686][ T5096] RIP: 0033:0x7f8dbc3eb8db
[   61.216978][ T5096] Code: 00 48 89 44 24 18 31 c0 48 8d 44 24 60 c7 04 24 10 00 00 00 48 89 44 24 08 48 8d 44 24 20 48 89 44 24 10 b8 10 00 00 00 0f 05 <89> c2 3d 00 f0 ff ff 77 1c 48 8b 44 24 18 64 48 2b 04 25 28 00 00
[   61.236339][ T5096] RSP: 002b:00007ffdb55284a0 EFLAGS: 00000246 ORIG_RAX: 0000000000000010
[   61.240308][  T259] 2026-01-11 12:02:14.799418 (+0000) -73855.722057 +/- 0.000324 internal-lkp-server 192.168.1.200 s5 no-leap
[   61.244561][ T5096] RAX: ffffffffffffffda RBX: 00007f8dbc4e2bd6 RCX: 00007f8dbc3eb8db
[   61.244563][ T5096] RDX: 000055c5ab615b30 RSI: 00000000c138fd04 RDI: 0000000000000004
[   61.244588][  T259] 
[   61.255911][ T5096] RBP: 00007ffdb55285c0 R08: 00007f8dbc535968 R09: 00007ffdb5528350
[   61.255926][ T5096] R10: 00007f8dbc534d18 R11: 0000000000000246 R12: 00007f8dbc534d18
[   61.264411][  T259] INFO: lkp CACHE_DIR is /opt/rootfs/tmp
[   61.271491][ T5096] R13: 00007f8dbc534d18 R14: 00007f8dbc534d18 R15: 00007f8dbc534d18
[   61.271495][ T5096]  </TASK>
[   61.273670][  T259] 
[   61.281448][ T5096] ---[ end trace 0000000000000000 ]---


> 
> > Ran: generic/629
> > Failures: generic/629
> > Failed 1 of 1 tests
> > 
> > 
> > 
> > 
> > The kernel config and materials to reproduce are available at:
> > https://download.01.org/0day-ci/archive/20260112/[email protected]
> > 
> > 
> > 
>