------------[ cut here ]------------ failed to allocate ring buffer on CPU 0 WARNING: kernel/trace/ring_buffer.c:8094 at trace_rb_cpu_prepare+0x463/0x520 kernel/trace/ring_buffer.c:8094, CPU#1: syz.1.1716/13343 Modules linked in: CPU: 1 UID: 0 PID: 13343 Comm: syz.1.1716 Tainted: G L syzkaller #0 PREEMPT(full) Tainted: [L]=SOFTLOCKUP Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 11/06/2026 RIP: 0010:trace_rb_cpu_prepare+0x465/0x520 kernel/trace/ring_buffer.c:8094 Code: 48 c1 ea 03 80 3c 02 00 0f 84 bc fc ff ff 48 8b 3c 24 e8 4e ea 75 00 e9 ae fc ff ff e8 e4 7f fb ff 48 8d 3d 8d 8f 5b 10 89 ee <67> 48 0f b9 3a bb f4 ff ff ff e9 d3 fd ff ff 4c 89 ef e8 24 ea 75 RSP: 0018:ffffc90006a5f8d8 EFLAGS: 00010287 RAX: 0000000000019e8b RBX: ffff88807a897cb8 RCX: ffffc900042ba000 RDX: 0000000000080000 RSI: 0000000000000000 RDI: ffffffff926e8bf0 RBP: 0000000000000000 R08: ffff888021a9b880 R09: 0000000000000000 R10: 0000000000000001 R11: ffffffff8288b844 R12: 0000000000000000 R13: ffff88807a897c10 R14: 0000000000000162 R15: 0000000000000000 FS: 00007f6b963366c0(0000) GS:ffff888122575000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: 0000001b2f4f5ff8 CR3: 0000000074cfc000 CR4: 00000000003526f0 Call Trace: cpuhp_invoke_callback+0x205/0x9a0 kernel/cpu.c:204 cpuhp_issue_call+0x1b8/0x970 kernel/cpu.c:2354 __cpuhp_state_add_instance_cpuslocked+0x2d7/0x400 kernel/cpu.c:2423 __cpuhp_state_add_instance+0xd5/0x2d0 kernel/cpu.c:2444 cpuhp_state_add_instance include/linux/cpuhotplug.h:377 [inline] alloc_buffer+0x53b/0x1610 kernel/trace/ring_buffer.c:2922 __ring_buffer_alloc+0x2d/0x40 kernel/trace/ring_buffer.c:2964 allocate_trace_buffer+0x150/0xa30 kernel/trace/trace.c:8535 allocate_trace_buffers kernel/trace/trace.c:8568 [inline] trace_array_create_systems+0x582/0xc30 kernel/trace/trace.c:8746 trace_array_create kernel/trace/trace.c:8789 [inline] instance_mkdir+0xca/0x140 kernel/trace/trace.c:8804 tracefs_syscall_mkdir+0x10e/0x180 fs/tracefs/inode.c:121 vfs_mkdir+0x36d/0x8a0 fs/namei.c:5428 filename_mkdirat+0x4c4/0x630 fs/namei.c:5461 __do_sys_mkdirat fs/namei.c:5482 [inline] __se_sys_mkdirat fs/namei.c:5479 [inline] __x64_sys_mkdirat+0x89/0xc0 fs/namei.c:5479 do_syscall_x64 arch/x86/entry/syscall_64.c:61 [inline] do_syscall_64+0x123/0x790 arch/x86/entry/syscall_64.c:84 entry_SYSCALL_64_after_hwframe+0x77/0x7f RIP: 0033:0x7f6b9539fb19 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:00007f6b96336028 EFLAGS: 00000246 ORIG_RAX: 0000000000000102 RAX: ffffffffffffffda RBX: 00007f6b95625fa0 RCX: 00007f6b9539fb19 RDX: 00000000000001ff RSI: 0000200000000740 RDI: ffffffffffffff9c RBP: 00007f6b95437b70 R08: 0000000000000000 R09: 0000000000000000 R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000 R13: 00007f6b95626038 R14: 00007f6b95625fa0 R15: 00007ffc46cb1e48 ---------------- Code disassembly (best guess): 0: 48 c1 ea 03 shr $0x3,%rdx 4: 80 3c 02 00 cmpb $0x0,(%rdx,%rax,1) 8: 0f 84 bc fc ff ff je 0xfffffcca e: 48 8b 3c 24 mov (%rsp),%rdi 12: e8 4e ea 75 00 call 0x75ea65 17: e9 ae fc ff ff jmp 0xfffffcca 1c: e8 e4 7f fb ff call 0xfffb8005 21: 48 8d 3d 8d 8f 5b 10 lea 0x105b8f8d(%rip),%rdi # 0x105b8fb5 28: 89 ee mov %ebp,%esi * 2a: 67 48 0f b9 3a ud1 (%edx),%rdi <-- trapping instruction 2f: bb f4 ff ff ff mov $0xfffffff4,%ebx 34: e9 d3 fd ff ff jmp 0xfffffe0c 39: 4c 89 ef mov %r13,%rdi 3c: e8 .byte 0xe8 3d: 24 ea and $0xea,%al 3f: 75 .byte 0x75