syzbot |
sign-in | mailing list | source | docs |
rcu: INFO: rcu_preempt detected stalls on CPUs/tasks: rcu: Tasks blocked on level-0 rcu_node (CPUs 0-1): P15730/1:b..l P15731/1:b..l P15692/2:b..l (detected by 0, t=10502 jiffies, g=92533, q=871 ncpus=2) task:syz.8.2454 state:R running task stack:23600 pid:15692 ppid:8472 flags:0x00004004 Call Trace: <TASK> context_switch kernel/sched/core.c:5245 [inline] __schedule+0x11d1/0x40e0 kernel/sched/core.c:6562 preempt_schedule_irq+0xbb/0x160 kernel/sched/core.c:6874 irqentry_exit+0x63/0x70 kernel/entry/common.c:439 asm_sysvec_apic_timer_interrupt+0x16/0x20 arch/x86/include/asm/idtentry.h:691 RIP: 0010:check_kcov_mode kernel/kcov.c:193 [inline] RIP: 0010:write_comp_data kernel/kcov.c:245 [inline] RIP: 0010:__sanitizer_cov_trace_const_cmp1+0x32/0x80 kernel/kcov.c:299 Code: 64 fa 7f 7e 65 8b 0d 65 fa 7f 7e 81 e1 00 01 ff 00 74 11 81 f9 00 01 00 00 75 5b 83 ba 1c 16 00 00 00 74 52 8b 8a f8 15 00 00 <83> f9 03 75 47 48 8b 8a 00 16 00 00 44 8b 8a fc 15 00 00 49 c1 e1 RSP: 0018:ffffc90006226db8 EFLAGS: 00000246 RAX: ffffffff890d3e88 RBX: 1ffffffff1bc8155 RCX: 0000000000000002 RDX: ffff88802d1d8000 RSI: 0000000000000001 RDI: 0000000000000000 RBP: 0000000000000040 R08: ffff8880742d812f R09: ffff8880742d80e8 R10: dffffc0000000000 R11: ffffed100e85b026 R12: ffffffff8de40a80 R13: ffffffff8de40aa8 R14: 0000000000000001 R15: 0000000000000001 pfkey_send_acquire+0x1828/0x2d70 net/key/af_key.c:-1 km_query+0x10e/0x200 net/xfrm/xfrm_state.c:2244 xfrm_state_find+0x2016/0x2c10 net/xfrm/xfrm_state.c:1158 xfrm_tmpl_resolve_one net/xfrm/xfrm_policy.c:2424 [inline] xfrm_tmpl_resolve net/xfrm/xfrm_policy.c:2469 [inline] xfrm_resolve_and_create_bundle+0x774/0x2d30 net/xfrm/xfrm_policy.c:2762 xfrm_lookup_with_ifid+0x272/0x2050 net/xfrm/xfrm_policy.c:3096 xfrm_lookup net/xfrm/xfrm_policy.c:3225 [inline] xfrm_lookup_route+0x38/0x1b0 net/xfrm/xfrm_policy.c:3236 udp_sendmsg+0x1626/0x23b0 net/ipv4/udp.c:1247 sock_sendmsg_nosec net/socket.c:718 [inline] __sock_sendmsg net/socket.c:730 [inline] ____sys_sendmsg+0x5be/0x970 net/socket.c:2518 ___sys_sendmsg+0x2a2/0x360 net/socket.c:2572 __sys_sendmmsg+0x2c3/0x510 net/socket.c:2658 __do_sys_sendmmsg net/socket.c:2687 [inline] __se_sys_sendmmsg net/socket.c:2684 [inline] __x64_sys_sendmmsg+0x9c/0xb0 net/socket.c:2684 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: 0033:0x7fa2dff9aeb9 RSP: 002b:00007fa2e0f14028 EFLAGS: 00000246 ORIG_RAX: 0000000000000133 RAX: ffffffffffffffda RBX: 00007fa2e0216090 RCX: 00007fa2dff9aeb9 RDX: 000000000800001d RSI: 0000200000007fc0 RDI: 0000000000000003 RBP: 00007fa2e0008c1f R08: 0000000000000000 R09: 0000000000000000 R10: 000000000000001c R11: 0000000000000246 R12: 0000000000000000 R13: 00007fa2e0216128 R14: 00007fa2e0216090 R15: 00007ffd57272b88 </TASK> task:modprobe state:R running task stack:23696 pid:15731 ppid:4658 flags:0x00004000 Call Trace: <TASK> context_switch kernel/sched/core.c:5245 [inline] __schedule+0x11d1/0x40e0 kernel/sched/core.c:6562 preempt_schedule_irq+0xbb/0x160 kernel/sched/core.c:6874 irqentry_exit+0x63/0x70 kernel/entry/common.c:439 asm_sysvec_apic_timer_interrupt+0x16/0x20 arch/x86/include/asm/idtentry.h:691 RIP: 0010:mt_validate_nulls arch/x86/include/asm/atomic.h:-1 [inline] RIP: 0010:mt_validate+0x4447/0x4cb0 lib/maple_tree.c:7249 Code: 97 be 04 00 00 00 e8 48 68 b9 f7 f0 ff 05 01 85 ec 0c 48 c7 c7 e0 7b 06 97 be 04 00 00 00 e8 30 68 b9 f7 f0 ff 05 09 85 ec 0c <48> bb 00 00 00 00 00 fc ff df 4c 8b b4 24 b8 00 00 00 45 89 f7 41 RSP: 0018:ffffc9000c5df480 EFLAGS: 00000207 RAX: ffffffff8a19f601 RBX: 0000000000000005 RCX: ffffffff8a19f6d0 RDX: 0000000000000001 RSI: 0000000000000004 RDI: ffffffff97067be0 RBP: ffffc9000c5df630 R08: 0000000000000003 R09: 0000000000000004 R10: dffffc0000000000 R11: fffffbfff2e0cf7c R12: ffff88801dbe96d8 R13: ffff888060418080 R14: 0000000000000001 R15: 0000000000000300 validate_mm_mt+0xe2/0x440 mm/mmap.c:295 __split_vma+0x30/0x500 mm/mmap.c:2355 do_mas_align_munmap+0x7b9/0x12b0 mm/mmap.c:2501 do_mas_munmap+0x240/0x2b0 mm/mmap.c:2650 __mmap_region mm/mmap.c:2698 [inline] mmap_region+0x6e0/0x1ca0 mm/mmap.c:2916 do_mmap+0x964/0xfd0 mm/mmap.c:1436 vm_mmap_pgoff+0x1c1/0x2d0 mm/util.c:520 ksys_mmap_pgoff+0x516/0x6f0 mm/mmap.c:1482 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: 0033:0x7fe80037b242 RSP: 002b:00007ffe64b372a8 EFLAGS: 00000206 ORIG_RAX: 0000000000000009 RAX: ffffffffffffffda RBX: 00007fe800088000 RCX: 00007fe80037b242 RDX: 0000000000000003 RSI: 0000000000002000 RDI: 00007fe800088000 RBP: 0000000000000812 R08: 0000000000000000 R09: 000000000002c000 R10: 0000000000000812 R11: 0000000000000206 R12: 00007ffe64b37368 R13: 00007fe800358ab0 R14: 00007ffe64b37720 R15: 00000fffcc966e58 </TASK> task:modprobe state:R running task stack:24336 pid:15730 ppid:4495 flags:0x00004000 Call Trace: <TASK> context_switch kernel/sched/core.c:5245 [inline] __schedule+0x11d1/0x40e0 kernel/sched/core.c:6562 preempt_schedule_irq+0xbb/0x160 kernel/sched/core.c:6874 irqentry_exit+0x63/0x70 kernel/entry/common.c:439 asm_sysvec_apic_timer_interrupt+0x16/0x20 arch/x86/include/asm/idtentry.h:691 RIP: 0010:lock_acquire+0x225/0x4a0 kernel/locking/lockdep.c:5666 Code: f7 84 24 80 00 00 00 00 02 00 00 43 c6 44 3d 04 f8 0f 85 f0 00 00 00 41 f7 c6 00 02 00 00 74 01 fb 48 c7 44 24 60 0e 36 e0 45 <4b> c7 44 3d 00 00 00 00 00 43 c7 44 3d 08 00 00 00 00 65 48 8b 04 RSP: 0018:ffffc9000c60f0e0 EFLAGS: 00000206 RAX: 0000000000000001 RBX: 0000000000000000 RCX: 87568367f20f4100 RDX: 0000000000000000 RSI: ffffffff8a8c23a0 RDI: ffffffff8adf0c20 RBP: ffffc9000c60f1f8 R08: dffffc0000000000 R09: 1ffffffff215e648 R10: dffffc0000000000 R11: fffffbfff215e649 R12: 0000000000000001 R13: 1ffff920018c1e28 R14: 0000000000000246 R15: dffffc0000000000 rcu_lock_acquire include/linux/rcupdate.h:350 [inline] rcu_read_lock include/linux/rcupdate.h:791 [inline] is_bpf_text_address+0x43/0x2a0 kernel/bpf/core.c:735 kernel_text_address+0x9c/0xd0 kernel/extable.c:125 __kernel_text_address+0x9/0x30 kernel/extable.c:79 unwind_get_return_address+0x49/0x80 arch/x86/kernel/unwind_orc.c:323 arch_stack_walk+0xf2/0x140 arch/x86/kernel/stacktrace.c:26 stack_trace_save+0xa6/0xf0 kernel/stacktrace.c:122 kasan_save_stack mm/kasan/common.c:46 [inline] kasan_set_track+0x4b/0x70 mm/kasan/common.c:53 __kasan_slab_alloc+0x6b/0x80 mm/kasan/common.c:329 kasan_slab_alloc include/linux/kasan.h:201 [inline] slab_post_alloc_hook+0x4b/0x480 mm/slab.h:737 slab_alloc_node mm/slub.c:3359 [inline] slab_alloc mm/slub.c:3367 [inline] __kmem_cache_alloc_lru mm/slub.c:3374 [inline] kmem_cache_alloc+0x123/0x2f0 mm/slub.c:3383 mt_alloc_one lib/maple_tree.c:154 [inline] mas_alloc_nodes+0x2ec/0x890 lib/maple_tree.c:1279 mas_node_count_gfp lib/maple_tree.c:1361 [inline] mas_preallocate+0x161/0x3c0 lib/maple_tree.c:5809 do_mas_align_munmap+0x239/0x12b0 mm/mmap.c:2453 do_mas_munmap+0x240/0x2b0 mm/mmap.c:2650 __mmap_region mm/mmap.c:2698 [inline] mmap_region+0x6e0/0x1ca0 mm/mmap.c:2916 do_mmap+0x964/0xfd0 mm/mmap.c:1436 vm_mmap_pgoff+0x1c1/0x2d0 mm/util.c:520 ksys_mmap_pgoff+0x516/0x6f0 mm/mmap.c:1482 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: 0033:0x7f7117ce9242 RSP: 002b:00007fffd369d678 EFLAGS: 00000206 ORIG_RAX: 0000000000000009 RAX: ffffffffffffffda RBX: 00007f7117a15000 RCX: 00007f7117ce9242 RDX: 0000000000000005 RSI: 0000000000008000 RDI: 00007f7117a15000 RBP: 0000000000000812 R08: 0000000000000000 R09: 0000000000003000 R10: 0000000000000812 R11: 0000000000000206 R12: 00007fffd369d6c8 R13: 00007f7117cc5b20 R14: 00007fffd369dab0 R15: 00000ffffa6d3ad2 </TASK> rcu: rcu_preempt kthread starved for 10591 jiffies! g92533 f0x0 RCU_GP_WAIT_FQS(5) ->state=0x0 ->cpu=0 rcu: Unless rcu_preempt kthread gets sufficient CPU time, OOM is now expected behavior. rcu: RCU grace-period kthread stack dump: task:rcu_preempt state:R running task stack:26992 pid:16 ppid:2 flags:0x00004000 Call Trace: <TASK> context_switch kernel/sched/core.c:5245 [inline] __schedule+0x11d1/0x40e0 kernel/sched/core.c:6562 schedule+0xb9/0x180 kernel/sched/core.c:6638 schedule_timeout+0x184/0x2d0 kernel/time/timer.c:2168 rcu_gp_fqs_loop+0x303/0x1340 kernel/rcu/tree.c:1706 rcu_gp_kthread+0x99/0x3b0 kernel/rcu/tree.c:1905 kthread+0x29d/0x330 kernel/kthread.c:376 ret_from_fork+0x1f/0x30 arch/x86/entry/entry_64.S:295 </TASK> rcu: Stack dump where RCU GP kthread last ran: CPU: 0 PID: 0 Comm: swapper/0 Not tainted syzkaller #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 10/25/2025 RIP: 0010:default_idle+0xb/0x10 arch/x86/kernel/process.c:742 Code: 48 89 df e8 a7 10 9d f7 e9 44 ff ff ff e8 7d 07 f6 ff 00 00 cc cc 00 00 cc cc 00 00 cc cc 00 66 90 0f 00 2d 87 5d 50 00 fb f4 <c3> 0f 1f 40 00 41 57 41 56 53 49 be 00 00 00 00 00 fc ff df 65 48 RSP: 0018:ffffffff8c807d88 EFLAGS: 000002c6 RAX: ed6f06be66559200 RBX: ffffffff8a3651a7 RCX: ed6f06be66559200 RDX: 0000000000000001 RSI: ffffffff8a8c1220 RDI: ffffffff8adf0c20 RBP: ffffffff8c807ec0 R08: ffff8880b8e3580b R09: 1ffff110171c6b01 R10: dffffc0000000000 R11: ffffed10171c6b02 R12: 1ffffffff1900fbc R13: dffffc0000000000 R14: ffffffff8c8bc740 R15: 0000000000000000 FS: 0000000000000000(0000) GS:ffff8880b8e00000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: 00007feccfee9a90 CR3: 000000007ef43000 CR4: 00000000003506f0 DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000 DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400 Call Trace: <TASK> default_idle_call+0x84/0xc0 kernel/sched/idle.c:109 cpuidle_idle_call kernel/sched/idle.c:191 [inline] do_idle+0x20d/0x5a0 kernel/sched/idle.c:303 cpu_startup_entry+0x3f/0x60 kernel/sched/idle.c:401 rest_init+0x2dc/0x300 init/main.c:745 arch_call_rest_init+0xa/0xa init/main.c:905 start_kernel+0x493/0x53c init/main.c:1152 secondary_startup_64_no_verify+0xcf/0xdb </TASK>
| Time | Kernel | Commit | Syzkaller | Config | Log | Report | Syz repro | C repro | VM info | Assets (help?) | Manager | Title |
|---|---|---|---|---|---|---|---|---|---|---|---|---|
| 2026/02/03 18:40 | linux-6.1.y | cd9b81672742 | 6df4c87a | .config | console log | report | info | [disk image] [vmlinux] [kernel image] | ci2-linux-6-1-kasan | INFO: rcu detected stall in sys_sendmmsg | ||
| 2025/11/28 13:26 | linux-6.1.y | f6e38ae624cf | d6526ea3 | .config | console log | report | info | [disk image] [vmlinux] [kernel image] | ci2-linux-6-1-kasan | INFO: rcu detected stall in sys_sendmmsg |