BUG: unable to handle kernel paging request in snd_hdac_bus_parse_capabilities

Status: upstream: reported C repro on 2026/08/11 00:23
Subsystems: sound
Labels: prio:high
[Documentation on labels]
Reported-by: syzbot+10cd2d1efe8eeb604bee@syzkaller.appspotmail.com
First crash: 6d08h, last: 17h23m
✨ AI Patch Versions (2)
Version Stage Reported Report Link Job
2 moderation 2026/08/12 14:55 Discussion 4b8631e4-d809-4d13-954c-5333d467e539
1 moderation 2026/08/12 13:19 Discussion dd4258ea-3be3-4977-b597-0fc0910b0f51
✨ AI Jobs (4)
ID Workflow Result Correct Bug Created Started Finished Revision
4b8631e4 patch-iteration BUG: unable to handle kernel paging request in snd_hdac_bus_parse_capabilities 2026/08/12 14:12 2026/08/12 14:12 2026/08/12 14:55 a56bc0a5
dd4258ea patching BUG: unable to handle kernel paging request in snd_hdac_bus_parse_capabilities 2026/08/12 11:18 2026/08/12 11:18 2026/08/12 13:19 f8d35649
b848fffd repro-c Reproduced: ✅ BUG: unable to handle kernel paging request in snd_hdac_bus_parse_capabilities 2026/08/11 16:58 2026/08/11 21:16 2026/08/11 22:53 f8d35649
6ee3d5b8 assessment-security DenialOfService: ✅ Exploitable: ✅ FilesystemTrigger: ❌ NetworkTrigger: ❌ PeripheralTrigger: ✅ RemoteTrigger: ❌ Unprivileged: ❌ UserNamespace: ❌ VMGuestTrigger: ❌ VMHostTrigger: ✅ BUG: unable to handle kernel paging request in snd_hdac_bus_parse_capabilities 2026/08/09 05:25 2026/08/09 05:25 2026/08/09 06:07 5d63f80b
Discussions (1)
Title Replies (including bot) Last reply
[syzbot] [sound?] BUG: unable to handle kernel paging request in snd_hdac_bus_parse_capabilities 1 (3) 2026/08/12 12:31
Last patch testing requests (1)
Created Duration User Patch Repo Result
2026/08/12 10:07 20m nogikh@google.com upstream report job log log

Sample crash report:
BUG: unable to handle page fault for address: 000000000001c0b4
#PF: supervisor read access in kernel mode
#PF: error_code(0x0000) - not-present page
PGD 0 P4D 0 
Oops: Oops: 0000 [#1] SMP KASAN NOPTI
CPU: 1 UID: 0 PID: 1039 Comm: kworker/1:3 Not tainted syzkaller #0 PREEMPT(full) 
Hardware name: QEMU Standard PC (Q35 + ICH9, 2009), BIOS 1.16.3-debian-1.16.3-2 04/01/2014
Workqueue: events azx_probe_work
RIP: 0010:readw arch/x86/include/asm/io.h:58 [inline]
RIP: 0010:snd_hdac_reg_readw include/sound/hdaudio.h:458 [inline]
RIP: 0010:snd_hdac_bus_parse_capabilities+0x42/0x6d0 sound/hda/core/controller.c:412
Code: 97 f8 48 8d 45 20 48 89 c2 48 89 44 24 10 48 b8 00 00 00 00 00 fc ff df 48 c1 ea 03 80 3c 02 00 0f 85 f8 05 00 00 48 8b 45 20 <66> 44 8b 68 14 4c 8b 7c 24 10 48 89 e8 45 0f b7 ed 45 31 f6 48 ba
RSP: 0018:ffffc90005537ab0 EFLAGS: 00010246
RAX: 000000000001c0a0 RBX: ffff888027304058 RCX: ffffffff897e8c06
RDX: 1ffff11004e6080b RSI: ffffffff8972cfca RDI: ffff888027304038
RBP: ffff888027304038 R08: 0000000000000005 R09: 0000000000000003
R10: 0000000000000003 R11: 000000000000759b R12: 0000000000000003
R13: ffff8880294e4f44 R14: ffff888022d6c000 R15: 0000000000000000
FS:  0000000000000000(0000) GS:ffff8880d5eec000(0000) knlGS:0000000000000000
CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 000000000001c0b4 CR3: 000000005526e000 CR4: 0000000000352ef0
Call Trace:
 <TASK>
 azx_first_init sound/hda/controllers/intel.c:1936 [inline]
 azx_probe_continue sound/hda/controllers/intel.c:2365 [inline]
 azx_probe_work+0x1d8e/0x2640 sound/hda/controllers/intel.c:1737
 process_one_work+0xa23/0x1940 kernel/workqueue.c:3322
 process_scheduled_works kernel/workqueue.c:3405 [inline]
 worker_thread+0x5ef/0xe50 kernel/workqueue.c:3486
 kthread+0x370/0x450 kernel/kthread.c:436
 ret_from_fork+0x72b/0xd50 arch/x86/kernel/process.c:158
 ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:245
 </TASK>
Modules linked in:
CR2: 000000000001c0b4
---[ end trace 0000000000000000 ]---
RIP: 0010:readw arch/x86/include/asm/io.h:58 [inline]
RIP: 0010:snd_hdac_reg_readw include/sound/hdaudio.h:458 [inline]
RIP: 0010:snd_hdac_bus_parse_capabilities+0x42/0x6d0 sound/hda/core/controller.c:412
Code: 97 f8 48 8d 45 20 48 89 c2 48 89 44 24 10 48 b8 00 00 00 00 00 fc ff df 48 c1 ea 03 80 3c 02 00 0f 85 f8 05 00 00 48 8b 45 20 <66> 44 8b 68 14 4c 8b 7c 24 10 48 89 e8 45 0f b7 ed 45 31 f6 48 ba
RSP: 0018:ffffc90005537ab0 EFLAGS: 00010246
RAX: 000000000001c0a0 RBX: ffff888027304058 RCX: ffffffff897e8c06
RDX: 1ffff11004e6080b RSI: ffffffff8972cfca RDI: ffff888027304038
RBP: ffff888027304038 R08: 0000000000000005 R09: 0000000000000003
R10: 0000000000000003 R11: 000000000000759b R12: 0000000000000003
R13: ffff8880294e4f44 R14: ffff888022d6c000 R15: 0000000000000000
FS:  0000000000000000(0000) GS:ffff8880d5eec000(0000) knlGS:0000000000000000
CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 000000000001c0b4 CR3: 000000005526e000 CR4: 0000000000352ef0
----------------
Code disassembly (best guess):
   0:	97                   	xchg   %eax,%edi
   1:	f8                   	clc
   2:	48 8d 45 20          	lea    0x20(%rbp),%rax
   6:	48 89 c2             	mov    %rax,%rdx
   9:	48 89 44 24 10       	mov    %rax,0x10(%rsp)
   e:	48 b8 00 00 00 00 00 	movabs $0xdffffc0000000000,%rax
  15:	fc ff df
  18:	48 c1 ea 03          	shr    $0x3,%rdx
  1c:	80 3c 02 00          	cmpb   $0x0,(%rdx,%rax,1)
  20:	0f 85 f8 05 00 00    	jne    0x61e
  26:	48 8b 45 20          	mov    0x20(%rbp),%rax
* 2a:	66 44 8b 68 14       	mov    0x14(%rax),%r13w <-- trapping instruction
  2f:	4c 8b 7c 24 10       	mov    0x10(%rsp),%r15
  34:	48 89 e8             	mov    %rbp,%rax
  37:	45 0f b7 ed          	movzwl %r13w,%r13d
  3b:	45 31 f6             	xor    %r14d,%r14d
  3e:	48                   	rex.W
  3f:	ba                   	.byte 0xba

Crashes (8):
Time Kernel Commit Syzkaller Config Log Report Syz repro C repro VM info Assets (help?) Manager Title
2026/08/12 10:28 upstream f5bbbfec59b4 c38879ea .config console log report C ci-qemu-upstream BUG: unable to handle kernel paging request in snd_hdac_bus_parse_capabilities
2026/08/07 02:18 upstream 0d8395707651 c38879ea .config console log report info [disk image] [vmlinux] [kernel image] ci-upstream-kasan-gce-selinux-root BUG: unable to handle kernel paging request in snd_hdac_bus_parse_capabilities
2026/08/06 23:33 upstream 0d8395707651 c38879ea .config console log report info [disk image] [vmlinux] [kernel image] ci-upstream-kasan-gce-selinux-root BUG: unable to handle kernel paging request in snd_hdac_bus_parse_capabilities
2026/08/06 19:46 upstream 0d8395707651 c38879ea .config console log report info [disk image] [vmlinux] [kernel image] ci-upstream-kasan-gce-selinux-root BUG: unable to handle kernel paging request in snd_hdac_bus_parse_capabilities
2026/08/09 11:26 upstream 06cf61899d64 5d63f80b .config console log report info [disk image (non-bootable)] [vmlinux] [kernel image] ci-qemu-upstream-386 BUG: unable to handle kernel paging request in snd_hdac_bus_parse_capabilities
2026/08/08 13:54 upstream a59f57e2aa12 5d63f80b .config console log report info [disk image (non-bootable)] [vmlinux] [kernel image] ci-qemu-upstream-386 BUG: unable to handle kernel paging request in snd_hdac_bus_parse_capabilities
2026/08/07 18:24 upstream f9a2394a2348 e4ef95d6 .config console log report info [disk image (non-bootable)] [vmlinux] [kernel image] ci-qemu-upstream-386 BUG: unable to handle kernel paging request in snd_hdac_bus_parse_capabilities
2026/08/07 11:41 upstream f9a2394a2348 e4ef95d6 .config console log report info [disk image (non-bootable)] [vmlinux] [kernel image] ci-qemu-upstream-386 BUG: unable to handle kernel paging request in snd_hdac_bus_parse_capabilities
* Struck through repros no longer work on HEAD.