Subject: [linux-next20250911]Kernel OOPs while running generic/256 on Pmem device

From: Venkat Rao Bagalkote <[email-masked]>
Date: Fri, 12 Sep 2025 10:51:18 +0530

Greetings!!!

IBM CI has reported a kernel crash, while running generic/256 test case 
on pmem device from xfstests suite on linux-next20250911 kernel.

xfstests: git://git.kernel.org/pub/scm/fs/xfs/xfstests-dev.git

local.config:

[xfs_dax]
export RECREATE_TEST_DEV=true
export TEST_DEV=/dev/pmem0
export TEST_DIR=/mnt/test_pmem
export SCRATCH_DEV=/dev/pmem0.1
export SCRATCH_MNT=/mnt/scratch_pmem
export MKFS_OPTIONS="-m reflink=0 -b size=65536 -s size=512"
export FSTYP=xfs
export MOUNT_OPTIONS="-o dax"

Test case: generic/256

Traces:

[  163.371929] ------------[ cut here ]------------
[  163.371936] kernel BUG at lib/list_debug.c:29!
[  163.371946] Oops: Exception in kernel mode, sig: 5 [#1]
[  163.371954] LE PAGE_SIZE=64K MMU=Radix  SMP NR_CPUS=8192 NUMA pSeries
[  163.371965] Modules linked in: xfs nft_fib_inet nft_fib_ipv4 
nft_fib_ipv6 nft_fib nft_reject_inet nf_reject_ipv4 nf_reject_ipv6 
nft_reject nft_ct nft_chain_nat nf_nat nf_conntrack bonding tls 
nf_defrag_ipv6 nf_defrag_ipv4 rfkill ip_set nf_tables nfnetlink sunrpc 
pseries_rng vmx_crypto dax_pmem fuse ext4 crc16 mbcache jbd2 nd_pmem 
papr_scm sd_mod libnvdimm sg ibmvscsi ibmveth scsi_transport_srp pseries_wdt
[  163.372127] CPU: 22 UID: 0 PID: 130 Comm: kworker/22:0 Kdump: loaded 
Not tainted 6.17.0-rc5-next-20250911 #1 VOLUNTARY
[  163.372142] Hardware name: IBM,9080-HEX Power11 (architected) 
0x820200 0xf000007 of:IBM,FW1110.01 (NH1110_069) hv:phyp pSeries
[  163.372155] Workqueue: cgroup_free css_free_rwork_fn
[  163.372169] NIP:  c000000000d051d4 LR: c000000000d051d0 CTR: 
0000000000000000
[  163.372176] REGS: c00000000ba079b0 TRAP: 0700   Not tainted 
(6.17.0-rc5-next-20250911)
[  163.372183] MSR:  800000000282b033 <SF,VEC,VSX,EE,FP,ME,IR,DR,RI,LE>  
CR: 28000000  XER: 00000006
[  163.372214] CFAR: c0000000002bae9c IRQMASK: 0
[  163.372214] GPR00: c000000000d051d0 c00000000ba07c50 c00000000230a600 
0000000000000075
[  163.372214] GPR04: 0000000000000004 0000000000000001 c000000000507e2c 
0000000000000001
[  163.372214] GPR08: c000000d0cb87d13 0000000000000000 0000000000000000 
a80e000000000000
[  163.372214] GPR12: c00e0001a1970fa2 c000000d0ddec700 c000000000208e58 
c000000107b5e190
[  163.372214] GPR16: c00000000d3e5d08 c00000000b71cf78 c00000000d3e5d05 
c00000000b71cf30
[  163.372214] GPR20: c00000000b71cf08 c00000000b71cf10 c000000019f58588 
c000000004704bc8
[  163.372214] GPR24: c000000107b5e100 c000000004704bd0 0000000000000003 
c000000004704bd0
[  163.372214] GPR28: c000000004704bc8 c000000019f585a8 c000000019f53da8 
c000000004704bc8
[  163.372315] NIP [c000000000d051d4] __list_add_valid_or_report+0x124/0x188
[  163.372326] LR [c000000000d051d0] __list_add_valid_or_report+0x120/0x188
[  163.372335] Call Trace:
[  163.372339] [c00000000ba07c50] [c000000000d051d0] 
__list_add_valid_or_report+0x120/0x188 (unreliable)
[  163.372352] [c00000000ba07ce0] [c000000000834280] 
mem_cgroup_css_free+0xa0/0x27c
[  163.372363] [c00000000ba07d50] [c0000000003ba198] 
css_free_rwork_fn+0xd0/0x59c
[  163.372374] [c00000000ba07da0] [c0000000001f5d60] 
process_one_work+0x41c/0x89c
[  163.372385] [c00000000ba07eb0] [c0000000001f76c0] 
worker_thread+0x558/0x848
[  163.372394] [c00000000ba07f80] [c000000000209038] kthread+0x1e8/0x230
[  163.372406] [c00000000ba07fe0] [c00000000000ded8] 
start_kernel_thread+0x14/0x18
[  163.372416] Code: 4b9b1099 60000000 7f63db78 4bae8245 60000000 
e8bf0008 3c62ff88 7fe6fb78 7fc4f378 38637d40 4b5b5c89 60000000 
<0fe00000> 60000000 60000000 7f83e378
[  163.372453] ---[ end trace 0000000000000000 ]---
[  163.380581] pstore: backend (nvram) writing error (-1)
[  163.380593]

If you happen to fix this issue, please add below tag.

Reported-by: Venkat Rao Bagalkote <[email-masked]>

Regards,

Venkat.