[syzbot ci] Re: Introduce Per-CPU Work helpers (was QPW)

[syzbot ci <syzbot+ci1f8633521f2ac20d@syzkaller.appspotmail.com>]

syzbot ci has tested the following series

[v4] Introduce Per-CPU Work helpers (was QPW)
https://lore.kernel.org/all/20260519012754.240804-1-leobras.c@gmail.com
* [PATCH v4 1/4] Introducing pw_lock() and per-cpu queue & flush work
* [PATCH v4 2/4] mm/swap: move bh draining into a separate workqueue
* [PATCH v4 3/4] swap: apply new pw_queue_on() interface
* [PATCH v4 4/4] slub: apply new pw_queue_on() interface

and found the following issue:
WARNING in __pcs_replace_empty_main

Full report is available here:
https://ci.syzbot.org/series/804f81bd-77b4-490e-bd57-6345ad2aa923

***

WARNING in __pcs_replace_empty_main

tree:      drm-next
URL:       https://gitlab.freedesktop.org/drm/kernel.git
base:      5200f5f493f79f14bbdc349e402a40dfb32f23c8
arch:      amd64
compiler:  Debian clang version 21.1.8 (++20251221033036+2078da43e25a-1~exp1~20251221153213.50), Debian LLD 21.1.8
config:    https://ci.syzbot.org/builds/3ea80958-13bd-49da-9c64-6deb788113f8/config

clocksource: refined-jiffies: mask: 0xffffffff max_cycles: 0xffffffff, max_idle_ns: 19112604462750000 ns
Zone ranges:
  DMA      [mem 0x0000000000001000-0x0000000000ffffff]
  DMA32    [mem 0x0000000001000000-0x00000000ffffffff]
  Normal   [mem 0x0000000100000000-0x000000023fffffff]
  Device   empty
Movable zone start for each node
Early memory node ranges
  node   0: [mem 0x0000000000001000-0x000000000009efff]
  node   0: [mem 0x0000000000100000-0x000000007ffdefff]
  node   0: [mem 0x0000000100000000-0x0000000160000fff]
  node   1: [mem 0x0000000160001000-0x000000023fffffff]
Initmem setup node 0 [mem 0x0000000000001000-0x0000000160000fff]
Initmem setup node 1 [mem 0x0000000160001000-0x000000023fffffff]
On node 0, zone DMA: 1 pages in unavailable ranges
On node 0, zone DMA: 97 pages in unavailable ranges
On node 0, zone Normal: 33 pages in unavailable ranges
setup_percpu: NR_CPUS:8 nr_cpumask_bits:2 nr_cpu_ids:2 nr_node_ids:2
percpu: Embedded 71 pages/cpu s250632 r8192 d31992 u2097152
kvm-guest: PV spinlocks disabled, no host support
Kernel command line: earlyprintk=serial net.ifnames=0 sysctl.kernel.hung_task_all_cpu_backtrace=1 ima_policy=tcb nf-conntrack-ftp.ports=20000 nf-conntrack-tftp.ports=20000 nf-conntrack-sip.ports=20000 nf-conntrack-irc.ports=20000 nf-conntrack-sane.ports=20000 binder.debug_mask=0 rcupdate.rcu_expedited=1 rcupdate.rcu_cpu_stall_cputime=1 no_hash_pointers page_owner=on sysctl.vm.nr_hugepages=4 sysctl.vm.nr_overcommit_hugepages=4 secretmem.enable=1 sysctl.max_rcu_stall_to_panic=1 msr.allow_writes=off coredump_filter=0xffff root=/dev/sda console=ttyS0 vsyscall=native numa=fake=2 kvm-intel.nested=1 spec_store_bypass_disable=prctl nopcid vivid.n_devs=64 vivid.multiplanar=1,2,1,2,1,2,1,2,1,2,1,2,1,2,1,2,1,2,1,2,1,2,1,2,1,2,1,2,1,2,1,2,1,2,1,2,1,2,1,2,1,2,1,2,1,2,1,2,1,2,1,2,1,2,1,2,1,2,1,2,1,2,1,2 netrom.nr_ndevs=32 rose.rose_ndevs=32 smp.csd_lock_timeout=100000 watchdog_thresh=55 workqueue.watchdog_thresh=140 sysctl.net.core.netdev_unregister_timeout_secs=140 dummy_hcd.num=32 max_loop=32 nbds_max=32 \
Kernel command line: comedi.comedi_num_legacy_minors=4 panic_on_warn=1 root=/dev/sda console=ttyS0 root=/dev/sda1
Unknown kernel command line parameters "nbds_max=32", will be passed to user space.
printk: log buffer data + meta data: 262144 + 917504 = 1179648 bytes
software IO TLB: area num 2.
Fallback order for Node 0: 0 1 
Fallback order for Node 1: 1 0 
Built 2 zonelists, mobility grouping on.  Total pages: 1834877
Policy zone: Normal
mem auto-init: stack:all(zero), heap alloc:on, heap free:off
stackdepot: allocating hash table via alloc_large_system_hash
stackdepot hash table entries: 1048576 (order: 12, 16777216 bytes, linear)
stackdepot: allocating space for 8192 stack pools via memblock
**********************************************************
**   NOTICE NOTICE NOTICE NOTICE NOTICE NOTICE NOTICE   **
**                                                      **
** This system shows unhashed kernel memory addresses   **
** via the console, logs, and other interfaces. This    **
** might reduce the security of your system.            **
**                                                      **
** If you see this message and you are not debugging    **
** the kernel, report this immediately to your system   **
** administrator!                                       **
**                                                      **
** Use hash_pointers=always to force this mode off      **
**                                                      **
**   NOTICE NOTICE NOTICE NOTICE NOTICE NOTICE NOTICE   **
**********************************************************
------------[ cut here ]------------
debug_locks && !(lock_is_held(&(&s->cpu_sheaves->lock)->dep_map) != 0)
WARNING: mm/slub.c:4601 at __pcs_replace_empty_main+0x51b/0x6e0, CPU#0: swapper/0
Modules linked in:
CPU: 0 UID: 0 PID: 0 Comm: swapper Not tainted syzkaller #0 PREEMPT(undef) 
Hardware name: QEMU Standard PC (Q35 + ICH9, 2009), BIOS 1.16.2-debian-1.16.2-1 04/01/2014
RIP: 0010:__pcs_replace_empty_main+0x51b/0x6e0
Code: 48 85 f6 74 15 4c 89 ff 48 89 c6 e8 af 5e ff ff 4d 89 74 24 38 e9 36 fc ff ff 49 89 44 24 40 4d 89 74 24 38 e9 27 fc ff ff 90 <0f> 0b 90 83 7b 2c 00 0f 85 23 fb ff ff 48 8b 1b e8 20 cd 82 09 41
RSP: 0000:ffffffff8e607d58 EFLAGS: 00010046
RAX: 0000000000000000 RBX: ffffffff91bb8398 RCX: 0000000000000002
RDX: 0000000000000cc0 RSI: ffffffff8e21ec94 RDI: ffffffff8c28b160
RBP: 0000000000000cc0 R08: 0000000000005e00 R09: 00000000477ac845
R10: 0000000047d13f7f R11: 000000002fa01ecd R12: ffff88812103f308
R13: 0000000000000000 R14: ffffffff91bb8398 R15: 0000000000000000
FS:  0000000000000000(0000) GS:ffff88818dc8a000(0000) knlGS:0000000000000000
CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: ffff88823ffff000 CR3: 000000000e74a000 CR4: 00000000000000b0
Call Trace:
 <TASK>
 kmem_cache_alloc_node_noprof+0x441/0x690
 do_kmem_cache_create+0x172/0x620
 create_boot_cache+0xbf/0x120
 kmem_cache_init+0x11a/0x1e0
 mm_core_init+0x7e/0xb0
 start_kernel+0x15a/0x3e0
 x86_64_start_reservations+0x24/0x30
 x86_64_start_kernel+0x143/0x1c0
 common_startup_64+0x13e/0x147
 </TASK>


***

If these findings have caused you to resend the series or submit a
separate fix, please add the following tag to your commit message:
  Tested-by: syzbot@syzkaller.appspotmail.com

---
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