syzbot


INFO: rcu detected stall in unwind_next_frame (2)

Status: upstream: reported on 2024/03/26 19:31
Reported-by: syzbot+7362ecb0936f0a31080e@syzkaller.appspotmail.com
First crash: 34d, last: 34d
Similar bugs (4)
Kernel Title Repro Cause bisect Fix bisect Count Last Reported Patched Status
upstream INFO: rcu detected stall in unwind_next_frame (2) kernel 1 248d 248d 0/26 auto-obsoleted due to no activity on 2023/10/24 10:24
upstream INFO: rcu detected stall in unwind_next_frame (3) kernel 1 182d 182d 0/26 auto-obsoleted due to no activity on 2024/01/29 09:37
linux-6.1 INFO: rcu detected stall in unwind_next_frame 1 200d 200d 0/3 auto-obsoleted due to no activity on 2024/01/21 04:23
upstream INFO: rcu detected stall in unwind_next_frame kernel 2 2171d 2174d 8/26 fixed on 2018/07/09 18:05

Sample crash report:
rcu: INFO: rcu_preempt detected stalls on CPUs/tasks:
rcu: 	1-...!: (1 GPs behind) idle=b78c/1/0x4000000000000000 softirq=39445/39448 fqs=13
	(detected by 0, t=10504 jiffies, g=48765, q=986 ncpus=2)
Sending NMI from CPU 0 to CPUs 1:
NMI backtrace for cpu 1
CPU: 1 PID: 46 Comm: kworker/u4:3 Not tainted 6.1.82-syzkaller #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 02/29/2024
Workqueue: bat_events batadv_iv_send_outstanding_bat_ogm_packet
RIP: 0010:__lock_release kernel/locking/lockdep.c:5346 [inline]
RIP: 0010:lock_release+0x28e/0xa20 kernel/locking/lockdep.c:5682
Code: 44 89 6c 24 3c 44 89 ea 85 c0 0f 84 f2 01 00 00 4d 85 e4 0f 84 1c 03 00 00 49 8d 5c 24 24 48 89 d8 48 c1 e8 03 42 0f b6 04 38 <84> c0 0f 85 0a 05 00 00 83 3b 00 0f 85 0b 04 00 00 4d 8d 74 24 20
RSP: 0018:ffffc900001e0b60 EFLAGS: 00000803
RAX: 0000000000000000 RBX: ffff888019af46d4 RCX: ffffc900001e0b03
RDX: 0000000000000002 RSI: ffff888057af5300 RDI: ffff888019af46b0
RBP: ffffc900001e0ca0 R08: dffffc0000000000 R09: fffffbfff1ce6c56
R10: 0000000000000000 R11: dffffc0000000001 R12: ffff888019af46b0
R13: 0000000000000002 R14: 000000000000000a R15: dffffc0000000000
FS:  0000000000000000(0000) GS:ffff8880b9900000(0000) knlGS:0000000000000000
CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 00007f5f997a8000 CR3: 00000000276f6000 CR4: 00000000003506e0
DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000
DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400
Call Trace:
 <NMI>
 </NMI>
 <IRQ>
 __raw_spin_unlock include/linux/spinlock_api_smp.h:141 [inline]
 _raw_spin_unlock+0x12/0x40 kernel/locking/spinlock.c:186
 spin_unlock include/linux/spinlock.h:391 [inline]
 advance_sched+0x68b/0x970 net/sched/sch_taprio.c:749
 __run_hrtimer kernel/time/hrtimer.c:1686 [inline]
 __hrtimer_run_queues+0x5e5/0xe50 kernel/time/hrtimer.c:1750
 hrtimer_interrupt+0x392/0x980 kernel/time/hrtimer.c:1812
 local_apic_timer_interrupt arch/x86/kernel/apic/apic.c:1095 [inline]
 __sysvec_apic_timer_interrupt+0x156/0x580 arch/x86/kernel/apic/apic.c:1112
 sysvec_apic_timer_interrupt+0x8c/0xb0 arch/x86/kernel/apic/apic.c:1106
 </IRQ>
 <TASK>
 asm_sysvec_apic_timer_interrupt+0x16/0x20 arch/x86/include/asm/idtentry.h:653
RIP: 0010:memset_erms+0xe/0x10 arch/x86/lib/memset_64.S:66
Code: b6 f6 48 b8 01 01 01 01 01 01 01 01 48 0f af c6 f3 48 ab 89 d1 f3 aa 4c 89 c8 c3 90 49 89 f9 40 88 f0 48 89 d1 f3 aa 4c 89 c8 <c3> 90 49 89 fa 40 0f b6 ce 48 b8 01 01 01 01 01 01 01 01 48 0f af
RSP: 0018:ffffc90000b77718 EFLAGS: 00000202
RAX: ffffc90000b77850 RBX: 1ffffffff1df0718 RCX: 0000000000000000
RDX: 0000000000000010 RSI: 0000000000000000 RDI: ffffc90000b77860
RBP: dffffc0000000000 R08: dffffc0000000000 R09: ffffc90000b77850
R10: 0000000000000000 R11: dffffc0000000001 R12: ffffc90000b77800
R13: ffffffff8ef838c0 R14: ffffc90000b77835 R15: ffffc90000b77850
 unwind_next_frame+0xde7/0x2220 arch/x86/kernel/unwind_orc.c:546
 arch_stack_walk+0x10d/0x140 arch/x86/kernel/stacktrace.c:25
 stack_trace_save+0x113/0x1c0 kernel/stacktrace.c:122
 kasan_save_stack mm/kasan/common.c:45 [inline]
 kasan_set_track+0x4b/0x70 mm/kasan/common.c:52
 kasan_save_free_info+0x27/0x40 mm/kasan/generic.c:516
 ____kasan_slab_free+0xd6/0x120 mm/kasan/common.c:236
 kasan_slab_free include/linux/kasan.h:177 [inline]
 slab_free_hook mm/slub.c:1724 [inline]
 slab_free_freelist_hook mm/slub.c:1750 [inline]
 slab_free mm/slub.c:3661 [inline]
 __kmem_cache_free+0x25c/0x3c0 mm/slub.c:3674
 process_one_work+0x8a9/0x11d0 kernel/workqueue.c:2292
 worker_thread+0xa47/0x1200 kernel/workqueue.c:2439
 kthread+0x28d/0x320 kernel/kthread.c:376
 ret_from_fork+0x1f/0x30 arch/x86/entry/entry_64.S:307
 </TASK>
rcu: rcu_preempt kthread starved for 10435 jiffies! g48765 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:26136 pid:16    ppid:2      flags:0x00004000
Call Trace:
 <TASK>
 context_switch kernel/sched/core.c:5245 [inline]
 __schedule+0x142d/0x4550 kernel/sched/core.c:6558
 schedule+0xbf/0x180 kernel/sched/core.c:6634
 schedule_timeout+0x1b9/0x300 kernel/time/timer.c:1935
 rcu_gp_fqs_loop+0x2d2/0x1120 kernel/rcu/tree.c:1706
 rcu_gp_kthread+0xa3/0x3a0 kernel/rcu/tree.c:1905
 kthread+0x28d/0x320 kernel/kthread.c:376
 ret_from_fork+0x1f/0x30 arch/x86/entry/entry_64.S:307
 </TASK>
rcu: Stack dump where RCU GP kthread last ran:
CPU: 0 PID: 11189 Comm: syz-executor.2 Not tainted 6.1.82-syzkaller #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 02/29/2024
RIP: 0010:csd_lock_wait kernel/smp.c:424 [inline]
RIP: 0010:smp_call_function_many_cond+0x1fb0/0x3460 kernel/smp.c:998
Code: 2f 44 89 ee 83 e6 01 31 ff e8 ec 42 0b 00 41 83 e5 01 49 bd 00 00 00 00 00 fc ff df 75 0a e8 77 3f 0b 00 e9 1b ff ff ff f3 90 <42> 0f b6 04 2b 84 c0 75 14 41 f7 07 01 00 00 00 0f 84 fe fe ff ff
RSP: 0018:ffffc900055377c0 EFLAGS: 00000246
RAX: ffffffff817f443b RBX: 1ffff110173281b1 RCX: 0000000000040000
RDX: ffffc90005d82000 RSI: 000000000003ffff RDI: 0000000000040000
RBP: ffffc90005537ba0 R08: ffffffff817f4404 R09: fffffbfff2092c45
R10: 0000000000000000 R11: dffffc0000000001 R12: 0000000800000000
R13: dffffc0000000000 R14: 0000000000000001 R15: ffff8880b9940d88
FS:  00007f72632276c0(0000) GS:ffff8880b9800000(0000) knlGS:0000000000000000
CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 00007f72625ad988 CR3: 0000000023556000 CR4: 00000000003506f0
DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000
DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400
Call Trace:
 <IRQ>
 </IRQ>
 <TASK>
 on_each_cpu_cond_mask+0x3b/0x80 kernel/smp.c:1166
 on_each_cpu include/linux/smp.h:71 [inline]
 text_poke_sync arch/x86/kernel/alternative.c:1334 [inline]
 text_poke_bp_batch+0x2bb/0x940 arch/x86/kernel/alternative.c:1534
 text_poke_flush arch/x86/kernel/alternative.c:1725 [inline]
 text_poke_finish+0x16/0x30 arch/x86/kernel/alternative.c:1732
 arch_jump_label_transform_apply+0x13/0x20 arch/x86/kernel/jump_label.c:146
 static_key_slow_inc_cpuslocked+0x12a/0x220 kernel/jump_label.c:144
 static_key_slow_inc+0x16/0x20 kernel/jump_label.c:159
 bpf_enable_runtime_stats kernel/bpf/syscall.c:4840 [inline]
 bpf_enable_stats+0xfe/0x140 kernel/bpf/syscall.c:4859
 __sys_bpf+0x60a/0x6c0 kernel/bpf/syscall.c:5088
 __do_sys_bpf kernel/bpf/syscall.c:5109 [inline]
 __se_sys_bpf kernel/bpf/syscall.c:5107 [inline]
 __x64_sys_bpf+0x78/0x90 kernel/bpf/syscall.c:5107
 do_syscall_x64 arch/x86/entry/common.c:51 [inline]
 do_syscall_64+0x3d/0xb0 arch/x86/entry/common.c:81
 entry_SYSCALL_64_after_hwframe+0x63/0xcd
RIP: 0033:0x7f726247dda9
Code: 28 00 00 00 75 05 48 83 c4 28 c3 e8 e1 20 00 00 90 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 b0 ff ff ff f7 d8 64 89 01 48
RSP: 002b:00007f72632270c8 EFLAGS: 00000246 ORIG_RAX: 0000000000000141
RAX: ffffffffffffffda RBX: 00007f72625abf80 RCX: 00007f726247dda9
RDX: 0000000000000000 RSI: 0000000000000000 RDI: 0000000000000020
RBP: 00007f72624ca47a R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000
R13: 000000000000000b R14: 00007f72625abf80 R15: 00007ffd68cd32c8
 </TASK>

Crashes (1):
Time Kernel Commit Syzkaller Config Log Report Syz repro C repro VM info Assets (help?) Manager Title
2024/03/26 19:31 linux-6.1.y d7543167affd 454571b6 .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-6-1-kasan INFO: rcu detected stall in unwind_next_frame
* Struck through repros no longer work on HEAD.