WARNING in trace_rb_cpu_prepare

Status: upstream: reported on 2026/08/03 11:32
Subsystems: trace
Labels: prio:low
[Documentation on labels]
Reported-by: syzbot+fbe07bcf949966f3c00f@syzkaller.appspotmail.com
First crash: 6d13h, last: 46m
✨ AI Jobs (1)
ID Workflow Result Correct Bug Created Started Finished Revision
e96a8265 assessment-security DenialOfService: ❌ Exploitable: ❌ FilesystemTrigger: ❌ NetworkTrigger: ❌ PeripheralTrigger: ❌ RemoteTrigger: ❌ Unprivileged: ❌ UserNamespace: ❌ VMGuestTrigger: ❌ VMHostTrigger: ❌ WARNING in trace_rb_cpu_prepare 2026/08/01 00:00 2026/08/01 00:00 2026/08/01 00:26 7664cf44
Discussions (1)
Title Replies (including bot) Last reply
[syzbot] [trace?] WARNING in trace_rb_cpu_prepare 0 (1) 2026/08/03 11:32
Similar bugs (3)
Kernel Title Rank 🛈 Repro Cause bisect Fix bisect Count Last Reported Patched Status
android-6-12 WARNING in trace_rb_cpu_prepare -1 2 4d17h 4d18h 0/1 premoderation: reported on 2026/08/01 06:47
linux-5.15 WARNING in trace_rb_cpu_prepare -1 3 2d06h 4d02h 0/3 upstream: reported on 2026/08/01 23:00
linux-6.6 WARNING in trace_rb_cpu_prepare -1 3 14h19m 4d15h 0/2 upstream: reported on 2026/08/01 09:59

Sample crash report:
------------[ cut here ]------------
failed to allocate ring buffer on CPU 0
WARNING: kernel/trace/ring_buffer.c:7977 at trace_rb_cpu_prepare+0x330/0x3c0 kernel/trace/ring_buffer.c:7976, CPU#1: syz.2.1325/24397
Modules linked in:
CPU: 1 UID: 0 PID: 24397 Comm: syz.2.1325 Not tainted syzkaller #0 PREEMPT_{RT,(full)} 
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 07/24/2026
RIP: 0010:trace_rb_cpu_prepare+0x332/0x3c0 kernel/trace/ring_buffer.c:7976
Code: 08 f0 48 0f ab 03 31 c0 48 83 c4 30 5b 41 5c 41 5d 41 5e 41 5f 5d c3 cc cc cc cc cc e8 17 3b fc ff 48 8d 3d d0 07 ea 0d 89 ee <67> 48 0f b9 3a b8 f4 ff ff ff eb d2 e8 fd 3a fc ff e9 ef fe ff ff
RSP: 0018:ffffc90003da77e0 EFLAGS: 00010283
RAX: ffffffff81c99e49 RBX: dffffc0000000000 RCX: 0000000000080000
RDX: ffffc9000dab9000 RSI: 0000000000000000 RDI: ffffffff8fb3a620
RBP: 0000000000000000 R08: ffffffff8fafa337 R09: 1ffffffff1f5f466
R10: dffffc0000000000 R11: fffffbfff1f5f467 R12: 0000000000000000
R13: ffff88805e141300 R14: ffff88802a5820a0 R15: 0000000000000000
FS:  00007efc721b66c0(0000) GS:ffff888125d3e000(0000) knlGS:0000000000000000
CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 0000001b2d50fff8 CR3: 000000002b5b4000 CR4: 00000000003526f0
Call Trace:
 <TASK>
 cpuhp_invoke_callback+0x498/0x810 kernel/cpu.c:204
 cpuhp_issue_call+0x3f0/0x750 kernel/cpu.c:-1
 __cpuhp_state_add_instance_cpuslocked+0x225/0x560 kernel/cpu.c:2423
 __cpuhp_state_add_instance+0x25/0x40 kernel/cpu.c:2444
 cpuhp_state_add_instance include/linux/cpuhotplug.h:384 [inline]
 alloc_buffer+0x18aa/0x1d50 kernel/trace/ring_buffer.c:2830
 __ring_buffer_alloc+0x2c/0x40 kernel/trace/ring_buffer.c:2872
 allocate_trace_buffer+0x1d2/0x950 kernel/trace/trace.c:8412
 allocate_trace_buffers kernel/trace/trace.c:8445 [inline]
 trace_array_create_systems+0x590/0xe60 kernel/trace/trace.c:8623
 trace_array_create kernel/trace/trace.c:8666 [inline]
 instance_mkdir+0xd5/0x140 kernel/trace/trace.c:8681
 tracefs_syscall_mkdir+0x11a/0x190 fs/tracefs/inode.c:121
 vfs_mkdir+0x402/0x620 fs/namei.c:5276
 filename_mkdirat+0x289/0x520 fs/namei.c:5309
 __do_sys_mkdirat fs/namei.c:5330 [inline]
 __se_sys_mkdirat+0x35/0x150 fs/namei.c:5327
 do_syscall_x64 arch/x86/entry/syscall_64.c:63 [inline]
 do_syscall_64+0x174/0x580 arch/x86/entry/syscall_64.c:94
 entry_SYSCALL_64_after_hwframe+0x77/0x7f
RIP: 0033:0x7efc73f5e0d9
Code: ff c3 66 2e 0f 1f 84 00 00 00 00 00 0f 1f 44 00 00 48 89 f8 48 89 f7 48 89 d6 48 89 ca 4d 89 c2 4d 89 c8 4c 8b 4c 24 08 0f 05 <48> 3d 01 f0 ff ff 73 01 c3 48 c7 c1 e8 ff ff ff f7 d8 64 89 01 48
RSP: 002b:00007efc721b6028 EFLAGS: 00000246 ORIG_RAX: 0000000000000102
RAX: ffffffffffffffda RBX: 00007efc741e5fa0 RCX: 00007efc73f5e0d9
RDX: 00000000000001ff RSI: 0000200000000140 RDI: ffffffffffffff9c
RBP: 00007efc73ff5024 R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000
R13: 00007efc741e6038 R14: 00007efc741e5fa0 R15: 00007ffd77071fb8
 </TASK>
----------------
Code disassembly (best guess):
   0:	08 f0                	or     %dh,%al
   2:	48 0f ab 03          	bts    %rax,(%rbx)
   6:	31 c0                	xor    %eax,%eax
   8:	48 83 c4 30          	add    $0x30,%rsp
   c:	5b                   	pop    %rbx
   d:	41 5c                	pop    %r12
   f:	41 5d                	pop    %r13
  11:	41 5e                	pop    %r14
  13:	41 5f                	pop    %r15
  15:	5d                   	pop    %rbp
  16:	c3                   	ret
  17:	cc                   	int3
  18:	cc                   	int3
  19:	cc                   	int3
  1a:	cc                   	int3
  1b:	cc                   	int3
  1c:	e8 17 3b fc ff       	call   0xfffc3b38
  21:	48 8d 3d d0 07 ea 0d 	lea    0xdea07d0(%rip),%rdi        # 0xdea07f8
  28:	89 ee                	mov    %ebp,%esi
* 2a:	67 48 0f b9 3a       	ud1    (%edx),%rdi <-- trapping instruction
  2f:	b8 f4 ff ff ff       	mov    $0xfffffff4,%eax
  34:	eb d2                	jmp    0x8
  36:	e8 fd 3a fc ff       	call   0xfffc3b38
  3b:	e9 ef fe ff ff       	jmp    0xffffff2f

Crashes (206):
Time Kernel Commit Syzkaller Config Log Report Syz repro C repro VM info Assets (help?) Manager Title
2026/08/05 23:58 upstream 0d8395707651 cd5b1963 .config console log report info [disk image] [vmlinux] [kernel image] ci2-upstream-fs WARNING in trace_rb_cpu_prepare
2026/08/05 22:36 upstream 0d8395707651 cd5b1963 .config console log report info [disk image] [vmlinux] [kernel image] ci2-upstream-fs WARNING in trace_rb_cpu_prepare
2026/08/05 22:32 upstream 0d8395707651 cd5b1963 .config console log report info [disk image] [vmlinux] [kernel image] ci2-upstream-fs WARNING in trace_rb_cpu_prepare
2026/08/05 17:29 upstream c21bb4193868 b3eac40e .config console log report info [disk image] [vmlinux] [kernel image] ci-upstream-kasan-gce-selinux-root WARNING in trace_rb_cpu_prepare
2026/08/05 16:15 upstream c21bb4193868 b3eac40e .config console log report info [disk image] [vmlinux] [kernel image] ci-upstream-kasan-gce-selinux-root WARNING in trace_rb_cpu_prepare
2026/08/05 15:08 upstream c21bb4193868 52aa2820 .config console log report info [disk image] [vmlinux] [kernel image] ci2-upstream-fs WARNING in trace_rb_cpu_prepare
2026/08/05 12:15 upstream c21bb4193868 b3eac40e .config console log report info [disk image] [vmlinux] [kernel image] ci-upstream-kasan-badwrites-root WARNING in trace_rb_cpu_prepare
2026/08/05 09:47 upstream c21bb4193868 b3eac40e .config console log report info [disk image] [vmlinux] [kernel image] ci-upstream-kasan-gce-smack-root WARNING in trace_rb_cpu_prepare
2026/08/05 07:24 upstream c21bb4193868 b3eac40e .config console log report info [disk image] [vmlinux] [kernel image] ci-upstream-kasan-gce-root WARNING in trace_rb_cpu_prepare
2026/08/05 07:15 upstream c21bb4193868 b3eac40e .config console log report info [disk image] [vmlinux] [kernel image] ci-upstream-kasan-gce-smack-root WARNING in trace_rb_cpu_prepare
2026/08/05 05:04 upstream c21bb4193868 52aa2820 .config console log report info [disk image] [vmlinux] [kernel image] ci2-upstream-fs WARNING in trace_rb_cpu_prepare
2026/08/05 03:13 upstream c21bb4193868 d4abbeac .config console log report info [disk image] [vmlinux] [kernel image] ci-upstream-kasan-gce-root WARNING in trace_rb_cpu_prepare
2026/08/05 01:40 upstream 562bfb501c54 d4abbeac .config console log report info [disk image] [vmlinux] [kernel image] ci2-upstream-fs WARNING in trace_rb_cpu_prepare
2026/08/04 21:21 upstream 562bfb501c54 d4abbeac .config console log report info [disk image] [vmlinux] [kernel image] ci2-upstream-fs WARNING in trace_rb_cpu_prepare
2026/08/04 18:40 upstream 848acc8ffe1b d4abbeac .config console log report info [disk image] [vmlinux] [kernel image] ci-upstream-kasan-gce-root WARNING in trace_rb_cpu_prepare
2026/08/04 16:32 upstream 848acc8ffe1b d4abbeac .config console log report info [disk image] [vmlinux] [kernel image] ci-upstream-kasan-gce-smack-root WARNING in trace_rb_cpu_prepare
2026/08/04 15:53 upstream 848acc8ffe1b d4abbeac .config console log report info [disk image] [vmlinux] [kernel image] ci-upstream-kasan-badwrites-root WARNING in trace_rb_cpu_prepare
2026/08/04 04:50 upstream c8e0d43058e6 a68cb31b .config console log report info [disk image] [vmlinux] [kernel image] ci-upstream-kasan-gce-selinux-root WARNING in trace_rb_cpu_prepare
2026/08/04 03:32 upstream c8e0d43058e6 a68cb31b .config console log report info [disk image] [vmlinux] [kernel image] ci-upstream-kasan-gce-selinux-root WARNING in trace_rb_cpu_prepare
2026/08/04 01:52 upstream 848acc8ffe1b 9451e17e .config console log report info [disk image] [vmlinux] [kernel image] ci2-upstream-fs WARNING in trace_rb_cpu_prepare
2026/08/03 23:49 upstream c8e0d43058e6 a68cb31b .config console log report info [disk image] [vmlinux] [kernel image] ci-upstream-kasan-badwrites-root WARNING in trace_rb_cpu_prepare
2026/08/03 17:17 upstream 075b74841bd0 a68cb31b .config console log report info [disk image] [vmlinux] [kernel image] ci-upstream-kasan-gce-root WARNING in trace_rb_cpu_prepare
2026/08/03 14:34 upstream 075b74841bd0 e611ffe1 .config console log report info [disk image] [vmlinux] [kernel image] ci-upstream-kasan-gce-selinux-root WARNING in trace_rb_cpu_prepare
2026/08/03 11:29 upstream 075b74841bd0 e611ffe1 .config console log report info [disk image] [vmlinux] [kernel image] ci-upstream-kasan-gce-smack-root WARNING in trace_rb_cpu_prepare
2026/08/03 06:10 upstream bd1dde877520 e611ffe1 .config console log report info [disk image] [vmlinux] [kernel image] ci-upstream-kasan-badwrites-root WARNING in trace_rb_cpu_prepare
2026/08/03 05:00 upstream bd1dde877520 e611ffe1 .config console log report info [disk image] [vmlinux] [kernel image] ci-upstream-kasan-gce-selinux-root WARNING in trace_rb_cpu_prepare
2026/08/03 03:27 upstream bd1dde877520 e611ffe1 .config console log report info [disk image] [vmlinux] [kernel image] ci-upstream-kasan-gce-smack-root WARNING in trace_rb_cpu_prepare
2026/08/03 01:47 upstream bd1dde877520 e611ffe1 .config console log report info [disk image] [vmlinux] [kernel image] ci-upstream-kasan-gce-smack-root WARNING in trace_rb_cpu_prepare
2026/08/02 21:18 upstream bd1dde877520 e611ffe1 .config console log report info [disk image] [vmlinux] [kernel image] ci-upstream-kasan-gce-root WARNING in trace_rb_cpu_prepare
2026/08/02 17:59 upstream 2d2338c93da7 e611ffe1 .config console log report info [disk image] [vmlinux] [kernel image] ci-upstream-kasan-gce-smack-root WARNING in trace_rb_cpu_prepare
2026/08/02 14:30 upstream 2d2338c93da7 e611ffe1 .config console log report info [disk image] [vmlinux] [kernel image] ci-upstream-kasan-gce-root WARNING in trace_rb_cpu_prepare
2026/08/02 14:30 upstream 2d2338c93da7 e611ffe1 .config console log report info [disk image] [vmlinux] [kernel image] ci-upstream-kasan-gce-root WARNING in trace_rb_cpu_prepare
2026/08/02 09:12 upstream 2d2338c93da7 e611ffe1 .config console log report info [disk image] [vmlinux] [kernel image] ci-upstream-kasan-gce-root WARNING in trace_rb_cpu_prepare
2026/08/02 06:39 upstream 2d2338c93da7 e611ffe1 .config console log report info [disk image] [vmlinux] [kernel image] ci-upstream-kasan-gce-selinux-root WARNING in trace_rb_cpu_prepare
2026/08/02 03:54 upstream 2d2338c93da7 e611ffe1 .config console log report info [disk image] [vmlinux] [kernel image] ci-upstream-kasan-gce-selinux-root WARNING in trace_rb_cpu_prepare
2026/08/02 02:21 upstream 2d2338c93da7 e611ffe1 .config console log report info [disk image] [vmlinux] [kernel image] ci-upstream-kasan-gce-selinux-root WARNING in trace_rb_cpu_prepare
2026/08/02 01:36 upstream 2d2338c93da7 e611ffe1 .config console log report info [disk image] [vmlinux] [kernel image] ci-upstream-kasan-gce-root WARNING in trace_rb_cpu_prepare
2026/07/31 20:11 upstream 8ba098e6b6ff 7664cf44 .config console log report info [disk image] [vmlinux] [kernel image] ci-upstream-kasan-gce-smack-root WARNING in trace_rb_cpu_prepare
2026/07/30 11:27 upstream 11028ab62899 2377cd3d .config console log report info [disk image] [vmlinux] [kernel image] ci-upstream-kasan-gce-smack-root WARNING in trace_rb_cpu_prepare
2026/08/03 22:10 upstream 075b74841bd0 bdd50915 .config console log report info [disk image (non-bootable)] [vmlinux] [kernel image] ci-qemu-upstream WARNING in trace_rb_cpu_prepare
2026/08/03 21:08 upstream 075b74841bd0 bdd50915 .config console log report info [disk image (non-bootable)] [vmlinux] [kernel image] ci-qemu-upstream WARNING in trace_rb_cpu_prepare
2026/08/03 13:51 upstream 075b74841bd0 bdd50915 .config console log report info [disk image (non-bootable)] [vmlinux] [kernel image] ci-qemu-upstream WARNING in trace_rb_cpu_prepare
2026/08/03 08:54 upstream 075b74841bd0 e611ffe1 .config console log report info [disk image (non-bootable)] [vmlinux] [kernel image] ci-qemu-upstream WARNING in trace_rb_cpu_prepare
2026/08/02 23:39 upstream bd1dde877520 e611ffe1 .config console log report info [disk image (non-bootable)] [vmlinux] [kernel image] ci-qemu-upstream WARNING in trace_rb_cpu_prepare
2026/08/02 20:01 upstream bd1dde877520 e611ffe1 .config console log report info [disk image (non-bootable)] [vmlinux] [kernel image] ci-qemu-upstream WARNING in trace_rb_cpu_prepare
2026/08/02 15:49 upstream 2d2338c93da7 e611ffe1 .config console log report info [disk image (non-bootable)] [vmlinux] [kernel image] ci-qemu-upstream WARNING in trace_rb_cpu_prepare
2026/08/05 21:30 upstream c21bb4193868 1eed00d1 .config console log report info [disk image (non-bootable)] [vmlinux] [kernel image] ci-qemu-upstream-386 WARNING in trace_rb_cpu_prepare
2026/08/05 08:36 upstream 562bfb501c54 52aa2820 .config console log report info [disk image (non-bootable)] [vmlinux] [kernel image] ci-qemu-upstream-386 WARNING in trace_rb_cpu_prepare
2026/08/02 11:22 upstream 2d2338c93da7 e611ffe1 .config console log report info [disk image (non-bootable)] [vmlinux] [kernel image] ci-qemu-upstream-386 WARNING in trace_rb_cpu_prepare
2026/08/05 11:10 linux-next cc2b5f627e8c b3eac40e .config console log report info [disk image] [vmlinux] [kernel image] ci-upstream-rust-kasan-gce WARNING in trace_rb_cpu_prepare
2026/08/04 19:46 linux-next cc2b5f627e8c d4abbeac .config console log report info [disk image] [vmlinux] [kernel image] ci-upstream-rust-kasan-gce WARNING in trace_rb_cpu_prepare
2026/08/05 18:29 git://git.kernel.org/pub/scm/linux/kernel/git/arm64/linux.git for-kernelci 7235a3e71949 b3eac40e .config console log report info [disk image] [vmlinux] [kernel image] ci-upstream-gce-arm64 WARNING in trace_rb_cpu_prepare
2026/08/05 14:35 git://git.kernel.org/pub/scm/linux/kernel/git/arm64/linux.git for-kernelci 7235a3e71949 b3eac40e .config console log report info [disk image] [vmlinux] [kernel image] ci-upstream-gce-arm64 WARNING in trace_rb_cpu_prepare
2026/08/03 07:19 git://git.kernel.org/pub/scm/linux/kernel/git/arm64/linux.git for-kernelci 7235a3e71949 e611ffe1 .config console log report info [disk image] [vmlinux] [kernel image] ci-upstream-gce-arm64 WARNING in trace_rb_cpu_prepare
2026/08/03 10:00 git://git.kernel.org/pub/scm/linux/kernel/git/riscv/linux.git for-next ea6dd1523941 e611ffe1 .config console log report info [disk image (non-bootable)] [vmlinux] [kernel image] ci-qemu2-riscv64 WARNING in trace_rb_cpu_prepare
* Struck through repros no longer work on HEAD.