INFO: rcu detected stall in __hrtimer_run_queues (2)

Status: auto-obsoleted due to no activity on 2025/09/29 21:02
Subsystems: kernel
[Documentation on labels]
First crash: 459d, last: 459d
▶ ▼ Similar bugs (7)
Kernel Title Rank 🛈 Repro Cause bisect Fix bisect Count Last Reported Patched Status
upstream INFO: rcu detected stall in __hrtimer_run_queues kernel 1 syz, C inconclusive done 22 1504d 2051d 0/29 auto-obsoleted due to no activity on 2022/12/19 03:45
linux-5.15 INFO: rcu detected stall in __hrtimer_run_queues 1 1 57d 57d 0/3 upstream: reported on 2026/08/07 07:45
upstream INFO: rcu detected stall in __hrtimer_run_queues (3) prio:high kernel 1 syz, C 51 4d07h 56d 0/29 upstream: reported C repro on 2026/08/08 20:09
upstream BUG: soft lockup in __hrtimer_run_queues (4) kernel 1 1 550d 546d 0/29 auto-obsoleted due to no activity on 2025/06/30 23:58
upstream BUG: soft lockup in __hrtimer_run_queues (2) kernel 1 1 826d 822d 0/29 auto-obsoleted due to no activity on 2024/09/27 22:42
upstream BUG: soft lockup in __hrtimer_run_queues (3) kernel 1 1 642d 638d 0/29 auto-obsoleted due to no activity on 2025/03/30 03:09
linux-6.1 BUG: soft lockup in __hrtimer_run_queues 1 1 1d09h 1d09h 0/3 upstream: reported on 2026/10/02 17:39

Sample crash report:
rcu: INFO: rcu_preempt detected stalls on CPUs/tasks:
rcu: 	(detected by 1, t=10503 jiffies, g=32813, q=135 ncpus=2)
rcu: All QSes seen, last rcu_preempt kthread activity 10500 (4295008345-4294997845), jiffies_till_next_fqs=1, root ->qsmask 0x0
rcu: rcu_preempt kthread starved for 10500 jiffies! g32813 f0x2 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:27272 pid:16    tgid:16    ppid:2      task_flags:0x208040 flags:0x00004000
Call Trace:
 <TASK>
 context_switch kernel/sched/core.c:5396 [inline]
 __schedule+0x116a/0x5de0 kernel/sched/core.c:6785
 __schedule_loop kernel/sched/core.c:6863 [inline]
 schedule+0xe7/0x3a0 kernel/sched/core.c:6878
 schedule_timeout+0x123/0x290 kernel/time/sleep_timeout.c:99
 rcu_gp_fqs_loop+0x1ea/0xb00 kernel/rcu/tree.c:2054
 rcu_gp_kthread+0x270/0x380 kernel/rcu/tree.c:2256
 kthread+0x3c2/0x780 kernel/kthread.c:464
 ret_from_fork+0x5d4/0x6f0 arch/x86/kernel/process.c:148
 ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:245
 </TASK>
rcu: Stack dump where RCU GP kthread last ran:
Sending NMI from CPU 1 to CPUs 0:
NMI backtrace for cpu 0
CPU: 0 UID: 0 PID: 11087 Comm: syz.3.1397 Not tainted 6.16.0-rc4-syzkaller-00013-g66701750d556 #0 PREEMPT(full) 
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 05/07/2025
RIP: 0010:hlock_class kernel/locking/lockdep.c:234 [inline]
RIP: 0010:check_wait_context kernel/locking/lockdep.c:4882 [inline]
RIP: 0010:__lock_acquire+0x336/0x1c90 kernel/locking/lockdep.c:5190
Code: d0 41 83 c6 01 44 3b b5 e8 0a 00 00 7d 30 49 63 c6 48 8d 04 80 41 0f b7 44 c4 20 66 25 ff 1f 0f b7 c0 48 0f a3 05 aa 4a 3b 14 <72> ab 8b 05 82 f5 43 19 85 c0 0f 84 f8 00 00 00 31 c9 eb a9 44 38
RSP: 0018:ffffc90000007928 EFLAGS: 00000003
RAX: 000000000000006d RBX: 0000000000000002 RCX: 0000000000000060
RDX: 0000000000000002 RSI: 0000000000000002 RDI: ffff88802511d3c0
RBP: ffff88802511c880 R08: 0000000000080000 R09: 0000000000000001
R10: 0000000000000050 R11: 0000000000000001 R12: ffff88802511d370
R13: ffff88802511d3c0 R14: 0000000000000001 R15: 0000000000000002
FS:  00007f0b203626c0(0000) GS:ffff888124752000(0000) knlGS:0000000000000000
CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 00002000000d4030 CR3: 0000000031856000 CR4: 00000000003526f0
Call Trace:
 <IRQ>
 lock_acquire kernel/locking/lockdep.c:5871 [inline]
 lock_acquire+0x179/0x350 kernel/locking/lockdep.c:5828
 __raw_spin_lock_irqsave include/linux/spinlock_api_smp.h:110 [inline]
 _raw_spin_lock_irqsave+0x3a/0x60 kernel/locking/spinlock.c:162
 debug_object_deactivate+0x135/0x3a0 lib/debugobjects.c:873
 debug_hrtimer_deactivate kernel/time/hrtimer.c:450 [inline]
 debug_deactivate kernel/time/hrtimer.c:490 [inline]
 __run_hrtimer kernel/time/hrtimer.c:1729 [inline]
 __hrtimer_run_queues+0x46f/0xad0 kernel/time/hrtimer.c:1825
 hrtimer_interrupt+0x397/0x8e0 kernel/time/hrtimer.c:1887
 local_apic_timer_interrupt arch/x86/kernel/apic/apic.c:1039 [inline]
 __sysvec_apic_timer_interrupt+0x108/0x3f0 arch/x86/kernel/apic/apic.c:1056
 instr_sysvec_apic_timer_interrupt arch/x86/kernel/apic/apic.c:1050 [inline]
 sysvec_apic_timer_interrupt+0x52/0xc0 arch/x86/kernel/apic/apic.c:1050
 asm_sysvec_apic_timer_interrupt+0x1a/0x20 arch/x86/include/asm/idtentry.h:702
RIP: 0010:__raw_spin_unlock_irqrestore include/linux/spinlock_api_smp.h:152 [inline]
RIP: 0010:_raw_spin_unlock_irqrestore+0x31/0x80 kernel/locking/spinlock.c:194
Code: f5 53 48 8b 74 24 10 48 89 fb 48 83 c7 18 e8 46 00 15 f6 48 89 df e8 2e 54 15 f6 f7 c5 00 02 00 00 75 23 9c 58 f6 c4 02 75 37 <bf> 01 00 00 00 e8 65 74 05 f6 65 8b 05 2e 6a 49 08 85 c0 74 16 5b
RSP: 0018:ffffc90000007de8 EFLAGS: 00000246
RAX: 0000000000000002 RBX: ffff8880b8427c80 RCX: 0000000000000002
RDX: 0000000000000000 RSI: ffffffff8de1a0ee RDI: ffffffff8c157ca0
RBP: 0000000000000283 R08: 0000000000000001 R09: 0000000000000001
R10: ffffffff90a80d57 R11: 0000000000000001 R12: ffff8880b8427c80
R13: 0000008d494d30d3 R14: ffff888144331418 R15: ffffffff878a0eb0
 __run_hrtimer kernel/time/hrtimer.c:1757 [inline]
 __hrtimer_run_queues+0x529/0xad0 kernel/time/hrtimer.c:1825
 hrtimer_run_softirq+0x17d/0x350 kernel/time/hrtimer.c:1842
 handle_softirqs+0x219/0x8e0 kernel/softirq.c:579
 __do_softirq kernel/softirq.c:613 [inline]
 invoke_softirq kernel/softirq.c:453 [inline]
 __irq_exit_rcu+0x109/0x170 kernel/softirq.c:680
 irq_exit_rcu+0x9/0x30 kernel/softirq.c:696
 instr_sysvec_apic_timer_interrupt arch/x86/kernel/apic/apic.c:1050 [inline]
 sysvec_apic_timer_interrupt+0xa4/0xc0 arch/x86/kernel/apic/apic.c:1050
 </IRQ>
 <TASK>
 asm_sysvec_apic_timer_interrupt+0x1a/0x20 arch/x86/include/asm/idtentry.h:702
RIP: 0010:__raw_spin_unlock_irqrestore include/linux/spinlock_api_smp.h:152 [inline]
RIP: 0010:_raw_spin_unlock_irqrestore+0x31/0x80 kernel/locking/spinlock.c:194
Code: f5 53 48 8b 74 24 10 48 89 fb 48 83 c7 18 e8 46 00 15 f6 48 89 df e8 2e 54 15 f6 f7 c5 00 02 00 00 75 23 9c 58 f6 c4 02 75 37 <bf> 01 00 00 00 e8 65 74 05 f6 65 8b 05 2e 6a 49 08 85 c0 74 16 5b
RSP: 0018:ffffc90005927858 EFLAGS: 00000246
RAX: 0000000000000002 RBX: ffff8880583c6a00 RCX: 0000000000000006
RDX: 0000000000000000 RSI: ffffffff8de1a0ee RDI: ffffffff8c157ca0
RBP: 0000000000000286 R08: 0000000000000001 R09: 0000000000000001
R10: ffffffff90a80d57 R11: 0000000000000000 R12: 0000000000000002
R13: ffff8880583c6870 R14: ffff8880583c6a40 R15: ffff8880583c63e8
 __unix_dgram_recvmsg+0x313/0xc50 net/unix/af_unix.c:2541
 unix_dgram_recvmsg+0xd0/0x110 net/unix/af_unix.c:2616
 sock_recvmsg_nosec net/socket.c:1017 [inline]
 ____sys_recvmsg+0x5f9/0x6b0 net/socket.c:2784
 ___sys_recvmsg+0x114/0x1a0 net/socket.c:2828
 do_recvmmsg+0x2fe/0x750 net/socket.c:2923
 __sys_recvmmsg net/socket.c:2997 [inline]
 __do_sys_recvmmsg net/socket.c:3020 [inline]
 __se_sys_recvmmsg net/socket.c:3013 [inline]
 __x64_sys_recvmmsg+0x22a/0x280 net/socket.c:3013
 do_syscall_x64 arch/x86/entry/syscall_64.c:63 [inline]
 do_syscall_64+0xcd/0x4c0 arch/x86/entry/syscall_64.c:94
 entry_SYSCALL_64_after_hwframe+0x77/0x7f
RIP: 0033:0x7f0b1f58e929
Code: ff ff c3 66 2e 0f 1f 84 00 00 00 00 00 0f 1f 40 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 a8 ff ff ff f7 d8 64 89 01 48
RSP: 002b:00007f0b20362038 EFLAGS: 00000246 ORIG_RAX: 000000000000012b
RAX: ffffffffffffffda RBX: 00007f0b1f7b6080 RCX: 00007f0b1f58e929
RDX: 0000000000010106 RSI: 00002000000000c0 RDI: 0000000000000003
RBP: 00007f0b1f610b39 R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000002 R11: 0000000000000246 R12: 0000000000000000
R13: 0000000000000001 R14: 00007f0b1f7b6080 R15: 00007ffe97e45b38
 </TASK>

Crashes (1):
Time Kernel Commit Syzkaller Config Log Report Syz repro C repro VM info Assets (help?) Manager Title
2025/07/01 20:55 upstream 66701750d556 ffe4b334 .config console log report info [disk image] [vmlinux] [kernel image] ci-upstream-kasan-gce-selinux-root INFO: rcu detected stall in __hrtimer_run_queues
* Struck through repros no longer work on HEAD.