[syzbot] [block?] BUG: unable to handle kernel paging request in blk_mq_complete_request_remote

[syzbot] [block?] BUG: unable to handle kernel paging request in blk_mq_complete_request_remote

[syzbot]

Hello,

syzbot found the following issue on:

HEAD commit:    68f892e99df9 Merge branch 'for-next/core' into for-kernelci
git tree:       git://git.kernel.org/pub/scm/linux/kernel/git/arm64/linux.git for-kernelci
console output: https://syzkaller.appspot.com/x/log.txt?x=135bb415580000
kernel config:  https://syzkaller.appspot.com/x/.config?x=d1128bc53f2ef7f3
dashboard link: https://syzkaller.appspot.com/bug?extid=2e3bf0bd49acd9b21d4b
compiler:       Debian clang version 22.1.8 (++20260613092233+e80beda6e255-1~exp1~20260613092250.77), Debian LLD 22.1.8
userspace arch: arm64

Unfortunately, I don't have any reproducer for this issue yet.

Downloadable assets:
disk image: https://storage.googleapis.com/syzbot-assets/f98dd20a7b98/disk-68f892e9.raw.xz
vmlinux: https://storage.googleapis.com/syzbot-assets/441f1ad32549/vmlinux-68f892e9.xz
kernel image: https://storage.googleapis.com/syzbot-assets/8da5227b7dc8/Image-68f892e9.gz.xz

IMPORTANT: if you fix the issue, please add the following tag to the commit:
Reported-by: syzbot+2e3bf0bd49acd9b21d4b@syzkaller.appspotmail.com

Unable to handle kernel paging request at virtual address dfff800000000031
KASAN: null-ptr-deref in range [0x0000000000000188-0x000000000000018f]
Mem abort info:
  ESR = 0x0000000096000005
  EC = 0x25: DABT (current EL), IL = 32 bits
  SET = 0, FnV = 0
  EA = 0, S1PTW = 0
  FSC = 0x05: level 1 translation fault
Data abort info:
  ISV = 0, ISS = 0x00000005, ISS2 = 0x00000000
  CM = 0, WnR = 0, TnD = 0, TagAccess = 0
  GCS = 0, Overlay = 0, DirtyBit = 0
[dfff800000000031] address between user and kernel address ranges
Internal error: Oops: 0000000096000005 [#1]  SMP
Modules linked in:
CPU: 1 UID: 0 PID: 8684 Comm: kworker/u8:27 Tainted: G             L      syzkaller #0 PREEMPT 
Tainted: [L]=SOFTLOCKUP
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 08/07/2026
Workqueue: nvme-reset-wq nvme_reset_work
pstate: 83400005 (Nzcv daif +PAN -UAO +TCO +DIT -SSBS BTYPE=--)
pc : blk_mq_complete_request_remote+0xc4/0x858 block/blk-mq.c:1297
lr : blk_mq_complete_request_remote+0x88/0x858 block/blk-mq.c:1289
sp : ffff800095647900
x29: ffff800095647980 x28: ffff800095647900 x27: dfff800000000000
x26: 0000000000000000 x25: ffff0000c648326a x24: dfff800000000000
x23: ffff700012ac8f20 x22: 1fffe000192284a4 x21: 1fffe00018c90648
x20: 000000000000018e x19: ffff0000c9142400 x18: 1fffe00034bbbe28
x17: 0000000000000003 x16: ffff800088b37000 x15: 0000000000000000
x14: 0000000000000000 x13: 0000000000000001 x12: 0000000000000004
x11: ffff700012ac8f3c x10: ffff8000884bb5d7 x9 : 1fffe00019228482
x8 : 0000000000000031 x7 : ffff80008281b4e0 x6 : 0000000000000000
x5 : 0000000000000000 x4 : 0000000000000001 x3 : ffff80008281f228
x2 : 0000000000000000 x1 : ffff0000d604ba80 x0 : 0000000000000000
Call trace:
 blk_mq_complete_request_remote+0xc4/0x858 block/blk-mq.c:1297 (P)
 nvme_try_complete_req drivers/nvme/host/nvme.h:823 [inline]
 nvme_handle_cqe drivers/nvme/host/pci.c:1590 [inline]
 nvme_poll_cq+0x4ec/0x106c drivers/nvme/host/pci.c:1621
 nvme_reap_pending_cqes drivers/nvme/host/pci.c:2078 [inline]
 nvme_dev_disable+0x384/0x540 drivers/nvme/host/pci.c:3328
 nvme_reset_work+0x510/0x69c drivers/nvme/host/pci.c:3490
 process_one_work kernel/workqueue.c:3322 [inline]
 process_scheduled_works+0x788/0x10b8 kernel/workqueue.c:3405
 worker_thread+0x798/0xbd0 kernel/workqueue.c:3486
 kthread+0x304/0x3d4 kernel/kthread.c:436
 ret_from_fork+0x10/0x20 arch/arm64/kernel/entry.S:838
Code: 97d02797 f9400288 91063914 d343fe88 (38f86908) 
---[ end trace 0000000000000000 ]---
----------------
Code disassembly (best guess):
   0:	97d02797 	bl	0xffffffffff409e5c
   4:	f9400288 	ldr	x8, [x20]
   8:	91063914 	add	x20, x8, #0x18e
   c:	d343fe88 	lsr	x8, x20, #3
* 10:	38f86908 	ldrsb	w8, [x8, x24] <-- trapping instruction


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