WARNING in trace_rb_cpu_prepare

Status: upstream: reported syz repro on 2026/08/08 09:55
Reported-by: syzbot+227af209f3d01c37011e@syzkaller.appspotmail.com
First crash: 21d, last: 8h33m
▶ ▼ Similar bugs (4)
Kernel Title Rank 🛈 Repro Cause bisect Fix bisect Count Last Reported Patched Status
upstream WARNING in trace_rb_cpu_prepare prio:low trace -1 syz 1327 21m 25d 0/29 upstream: reported syz repro on 2026/08/03 11:32
android-6-12 WARNING in trace_rb_cpu_prepare -1 6 6d12h 28d 0/1 premoderation: reported on 2026/08/01 06:47
linux-5.15 WARNING in trace_rb_cpu_prepare -1 11 3d12h 27d 0/3 upstream: reported on 2026/08/01 23:00
linux-6.6 WARNING in trace_rb_cpu_prepare -1 syz, C 11 4d05h 28d 0/2 upstream: reported C repro on 2026/08/01 09:59

Sample crash report:
------------[ cut here ]------------
failed to allocate ring buffer on CPU 1
WARNING: CPU: 0 PID: 4488 at kernel/trace/ring_buffer.c:5863 trace_rb_cpu_prepare+0x349/0x3c0 kernel/trace/ring_buffer.c:5862
Modules linked in:
CPU: 0 PID: 4488 Comm: syz.1.18 Not tainted syzkaller #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 07/24/2026
RIP: 0010:trace_rb_cpu_prepare+0x349/0x3c0 kernel/trace/ring_buffer.c:5862
Code: f0 48 0f ab 08 31 c0 48 83 c4 30 5b 41 5c 41 5d 41 5e 41 5f 5d c3 e8 56 05 fd ff 48 c7 c7 e0 72 90 8a 44 89 f6 e8 a7 8e c8 ff <0f> 0b b8 f4 ff ff ff eb d4 e8 39 05 fd ff 0f 0b e9 07 fd ff ff e8
RSP: 0018:ffffc90003597a98 EFLAGS: 00010246
RAX: 35a9f611babf9700 RBX: dffffc0000000000 RCX: ffff88802d8c1e00
RDX: 0000000000000000 RSI: 0000000000000001 RDI: 0000000000000002
RBP: ffff88802038db88 R08: ffffc90003597727 R09: 1ffff920006b2ee4
R10: dffffc0000000000 R11: fffff520006b2ee5 R12: ffff8880288f34b0
R13: 0000000000000000 R14: 0000000000000001 R15: ffff88802038db88
FS:  00007fda1099a6c0(0000) GS:ffff8880b8e00000(0000) knlGS:0000000000000000
CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 00007fda0fbeb7c0 CR3: 0000000028d10000 CR4: 00000000003506f0
DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000
DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400
Call Trace:
 <TASK>
 cpuhp_invoke_callback+0x481/0x7e0 kernel/cpu.c:202
 cpuhp_issue_call+0x452/0x7f0 kernel/cpu.c:-1
 __cpuhp_state_add_instance_cpuslocked+0x229/0x600 kernel/cpu.c:2078
 __cpuhp_state_add_instance+0x21/0x30 kernel/cpu.c:2099
 cpuhp_state_add_instance include/linux/cpuhotplug.h:396 [inline]
 __ring_buffer_alloc+0x336/0x5d0 kernel/trace/ring_buffer.c:1878
 allocate_trace_buffer kernel/trace/trace.c:9303 [inline]
 allocate_trace_buffers+0x70/0x2b0 kernel/trace/trace.c:9335
 trace_array_create+0x2d6/0xcb0 kernel/trace/trace.c:9478
 instance_mkdir+0xc8/0x120 kernel/trace/trace.c:9524
 tracefs_syscall_mkdir+0xb7/0x110 fs/tracefs/inode.c:87
 vfs_mkdir+0x386/0x570 fs/namei.c:4114
 do_mkdirat+0x1d8/0x440 fs/namei.c:4139
 __do_sys_mkdirat fs/namei.c:4154 [inline]
 __se_sys_mkdirat fs/namei.c:4152 [inline]
 __x64_sys_mkdirat+0x85/0x90 fs/namei.c:4152
 do_syscall_x64 arch/x86/entry/common.c:46 [inline]
 do_syscall_64+0x4c/0xa0 arch/x86/entry/common.c:76
 entry_SYSCALL_64_after_hwframe+0x68/0xd2
RIP: 0033:0x7fda0fb9e0d9
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:00007fda1099a028 EFLAGS: 00000246 ORIG_RAX: 0000000000000102
RAX: ffffffffffffffda RBX: 00007fda0fe26090 RCX: 00007fda0fb9e0d9
RDX: 00000000000001ff RSI: 0000200000000100 RDI: ffffffffffffff9c
RBP: 00007fda0fc35024 R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000
R13: 00007fda0fe26128 R14: 00007fda0fe26090 R15: 00007ffdf3e13038
 </TASK>

Crashes (18):
Time Kernel Commit Syzkaller Config Log Report Syz repro C repro VM info Assets (help?) Manager Title
2026/08/22 05:53 linux-6.1.y 7e6e67054721 1e72964b .config console log report syz / log [disk image] [vmlinux] [kernel image] ci2-linux-6-1-kasan WARNING in trace_rb_cpu_prepare
2026/08/29 01:58 linux-6.1.y d64a499eea6b 2f52988a .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-6-1-kasan WARNING in trace_rb_cpu_prepare
2026/08/29 01:58 linux-6.1.y d64a499eea6b 2f52988a .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-6-1-kasan WARNING in trace_rb_cpu_prepare
2026/08/27 20:39 linux-6.1.y 79a9660d699e 69a01293 .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-6-1-kasan WARNING in trace_rb_cpu_prepare
2026/08/26 09:18 linux-6.1.y 05208478041c 6a91adb4 .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-6-1-kasan WARNING in trace_rb_cpu_prepare
2026/08/25 10:16 linux-6.1.y 05208478041c 614e416a .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-6-1-kasan WARNING in trace_rb_cpu_prepare
2026/08/24 18:56 linux-6.1.y 05208478041c b55bd4c3 .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-6-1-kasan WARNING in trace_rb_cpu_prepare
2026/08/23 21:59 linux-6.1.y 05208478041c 1e72964b .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-6-1-kasan WARNING in trace_rb_cpu_prepare
2026/08/23 12:08 linux-6.1.y 7e6e67054721 1e72964b .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-6-1-kasan WARNING in trace_rb_cpu_prepare
2026/08/21 20:28 linux-6.1.y 7e6e67054721 1e72964b .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-6-1-kasan WARNING in trace_rb_cpu_prepare
2026/08/21 20:27 linux-6.1.y 7e6e67054721 1e72964b .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-6-1-kasan WARNING in trace_rb_cpu_prepare
2026/08/21 02:53 linux-6.1.y 7e6e67054721 1e72964b .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-6-1-kasan WARNING in trace_rb_cpu_prepare
2026/08/20 20:54 linux-6.1.y 7e6e67054721 1e72964b .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-6-1-kasan WARNING in trace_rb_cpu_prepare
2026/08/13 14:11 linux-6.1.y e4f7d8be268e 359b2492 .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-6-1-kasan WARNING in trace_rb_cpu_prepare
2026/08/12 09:15 linux-6.1.y e4f7d8be268e f8d35649 .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-6-1-kasan WARNING in trace_rb_cpu_prepare
2026/08/11 07:16 linux-6.1.y e4f7d8be268e 508909ea .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-6-1-kasan WARNING in trace_rb_cpu_prepare
2026/08/08 14:12 linux-6.1.y e4f7d8be268e 5d63f80b .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-6-1-kasan WARNING in trace_rb_cpu_prepare
2026/08/08 09:55 linux-6.1.y e4f7d8be268e 5d63f80b .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-6-1-kasan-arm64 WARNING in trace_rb_cpu_prepare
* Struck through repros no longer work on HEAD.