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INFO: rcu detected stall in mod_timer

Status: auto-closed as invalid on 2020/09/07 13:48
Subsystems: kernel
[Documentation on labels]
First crash: 1389d, last: 1389d
Similar bugs (2)
Kernel Title Repro Cause bisect Fix bisect Count Last Reported Patched Status
linux-4.19 INFO: rcu detected stall in mod_timer 13 1301d 1488d 0/1 auto-closed as invalid on 2021/01/03 01:48
linux-4.14 INFO: rcu detected stall in mod_timer 2 1447d 1492d 0/1 auto-closed as invalid on 2020/08/10 12:01

Sample crash report:
rcu: INFO: rcu_preempt self-detected stall on CPU
rcu: 	0-...!: (10500 ticks this GP) idle=4f2/1/0x4000000000000004 softirq=149262/149262 fqs=1 
	(t=10502 jiffies g=292813 q=44)
rcu: rcu_preempt kthread starved for 10501 jiffies! g292813 f0x0 RCU_GP_WAIT_FQS(5) ->state=0x0 ->cpu=1
rcu: 	Unless rcu_preempt kthread gets sufficient CPU time, OOM is now expected behavior.
rcu: RCU grace-period kthread stack dump:
rcu_preempt     R  running task    28832    10      2 0x80004000
Call Trace:
 context_switch kernel/sched/core.c:3430 [inline]
 __schedule+0x8f3/0x1fc0 kernel/sched/core.c:4156
 schedule+0xd0/0x2a0 kernel/sched/core.c:4231
 schedule_timeout+0x35c/0x850 kernel/time/timer.c:1897
 rcu_gp_fqs_loop kernel/rcu/tree.c:1856 [inline]
 rcu_gp_kthread+0xc74/0x1a10 kernel/rcu/tree.c:2026
 kthread+0x388/0x470 kernel/kthread.c:268
 ret_from_fork+0x24/0x30 arch/x86/entry/entry_64.S:351
NMI backtrace for cpu 0
CPU: 0 PID: 9295 Comm: syz-executor.4 Not tainted 5.7.0-syzkaller #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011
Call Trace:
 <IRQ>
 __dump_stack lib/dump_stack.c:77 [inline]
 dump_stack+0x188/0x20d lib/dump_stack.c:118
 nmi_cpu_backtrace.cold+0x70/0xb1 lib/nmi_backtrace.c:101
 nmi_trigger_cpumask_backtrace+0x1e6/0x221 lib/nmi_backtrace.c:62
 trigger_single_cpu_backtrace include/linux/nmi.h:164 [inline]
 rcu_dump_cpu_stacks+0x19b/0x1e5 kernel/rcu/tree_stall.h:320
 print_cpu_stall kernel/rcu/tree_stall.h:553 [inline]
 check_cpu_stall kernel/rcu/tree_stall.h:627 [inline]
 rcu_pending kernel/rcu/tree.c:3471 [inline]
 rcu_sched_clock_irq.cold+0x55a/0xd25 kernel/rcu/tree.c:2486
 update_process_times+0x25/0x60 kernel/time/timer.c:1726
 tick_sched_handle+0x9b/0x180 kernel/time/tick-sched.c:176
 tick_sched_timer+0x4e/0x140 kernel/time/tick-sched.c:1320
 __run_hrtimer kernel/time/hrtimer.c:1520 [inline]
 __hrtimer_run_queues+0x5ca/0xed0 kernel/time/hrtimer.c:1584
 hrtimer_interrupt+0x312/0x770 kernel/time/hrtimer.c:1646
 local_apic_timer_interrupt arch/x86/kernel/apic/apic.c:1080 [inline]
 smp_apic_timer_interrupt+0x15b/0x600 arch/x86/kernel/apic/apic.c:1105
 apic_timer_interrupt+0xf/0x20 arch/x86/entry/entry_64.S:829
RIP: 0010:arch_local_irq_restore arch/x86/include/asm/paravirt.h:765 [inline]
RIP: 0010:__raw_spin_unlock_irqrestore include/linux/spinlock_api_smp.h:160 [inline]
RIP: 0010:_raw_spin_unlock_irqrestore+0x8c/0xe0 kernel/locking/spinlock.c:191
Code: 48 c7 c0 c0 ae 94 89 48 ba 00 00 00 00 00 fc ff df 48 c1 e8 03 80 3c 10 00 75 37 48 83 3d 0b 8e b6 01 00 74 22 48 89 df 57 9d <0f> 1f 44 00 00 bf 01 00 00 00 e8 15 72 71 f9 65 8b 05 f6 fd 23 78
RSP: 0018:ffffc90000007c30 EFLAGS: 00000282 ORIG_RAX: ffffffffffffff13
RAX: 1ffffffff13295d8 RBX: 0000000000000282 RCX: 1ffffffff15173ba
RDX: dffffc0000000000 RSI: 0000000000000000 RDI: 0000000000000282
RBP: ffff8880ae627580 R08: 0000000000000000 R09: 0000000000000001
R10: ffffffff8c347a77 R11: fffffbfff1868f4e R12: ffff8880ae627580
R13: 00000000ffffffff R14: ffff888096a3f030 R15: ffff888096a3f020
 __mod_timer kernel/time/timer.c:1057 [inline]
 mod_timer+0x5ac/0xc20 kernel/time/timer.c:1100
 call_timer_fn+0x1ac/0x780 kernel/time/timer.c:1404
 expire_timers kernel/time/timer.c:1449 [inline]
 __run_timers kernel/time/timer.c:1773 [inline]
 __run_timers kernel/time/timer.c:1740 [inline]
 run_timer_softirq+0x623/0x1600 kernel/time/timer.c:1786
 __do_softirq+0x26c/0x9f7 kernel/softirq.c:292
 invoke_softirq kernel/softirq.c:373 [inline]
 irq_exit+0x192/0x1d0 kernel/softirq.c:413
 exiting_irq arch/x86/include/asm/apic.h:546 [inline]
 smp_apic_timer_interrupt+0x19e/0x600 arch/x86/kernel/apic/apic.c:1107
 apic_timer_interrupt+0xf/0x20 arch/x86/entry/entry_64.S:829
 </IRQ>
RIP: 0010:arch_local_irq_restore arch/x86/include/asm/paravirt.h:765 [inline]
RIP: 0010:kmem_cache_free+0xa4/0x320 mm/slab.c:3695
Code: e8 81 27 00 00 84 c0 74 76 41 f7 c4 00 02 00 00 74 4e e8 7f b4 c6 ff 48 83 3d 87 12 e2 07 00 0f 84 f8 01 00 00 4c 89 e7 57 9d <0f> 1f 44 00 00 4c 8b 64 24 20 0f 1f 44 00 00 65 8b 05 06 17 4f 7e
RSP: 0018:ffffc9000547f750 EFLAGS: 00000282 ORIG_RAX: ffffffffffffff13
RAX: 0000000000000000 RBX: ffff88809efd70c0 RCX: 1ffffffff15173ba
RDX: 1ffff1100a25d5c0 RSI: 0000000000000000 RDI: 0000000000000282
RBP: ffff8880aa012e00 R08: 0000000000000000 R09: 0000000000000001
R10: ffffffff8c3479a7 R11: fffffbfff1868f34 R12: 0000000000000282
R13: ffffffff81a82330 R14: 0000000000000000 R15: dffffc0000000000
 merge_or_add_vmap_area mm/vmalloc.c:803 [inline]
 __purge_vmap_area_lazy+0xf60/0x1f60 mm/vmalloc.c:1381
 _vm_unmap_aliases mm/vmalloc.c:1800 [inline]
 _vm_unmap_aliases+0x393/0x480 mm/vmalloc.c:1765
 change_page_attr_set_clr+0x1f9/0x7d0 arch/x86/mm/pat/set_memory.c:1732
 change_page_attr_clear arch/x86/mm/pat/set_memory.c:1789 [inline]
 set_memory_ro+0x78/0xa0 arch/x86/mm/pat/set_memory.c:1935
 bpf_jit_binary_lock_ro include/linux/filter.h:815 [inline]
 bpf_int_jit_compile+0xdc2/0x1164 arch/x86/net/bpf_jit_comp.c:1929
 bpf_prog_select_runtime+0x49a/0x830 kernel/bpf/core.c:1807
 bpf_prog_load+0xde1/0x1780 kernel/bpf/syscall.c:2211
 __do_sys_bpf+0x16df/0x3aa0 kernel/bpf/syscall.c:4120
 do_syscall_64+0xf6/0x7d0 arch/x86/entry/common.c:295
 entry_SYSCALL_64_after_hwframe+0x49/0xb3
RIP: 0033:0x45ca69
Code: 0d b7 fb ff c3 66 2e 0f 1f 84 00 00 00 00 00 66 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 0f 83 db b6 fb ff c3 66 2e 0f 1f 84 00 00 00 00
RSP: 002b:00007fb62ce4cc78 EFLAGS: 00000246 ORIG_RAX: 0000000000000141
RAX: ffffffffffffffda RBX: 00000000004da900 RCX: 000000000045ca69
RDX: 0000000000000048 RSI: 00000000200054c0 RDI: 0000000000000005
RBP: 000000000078bf00 R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000246 R12: 00000000ffffffff
R13: 000000000000006a R14: 00000000004c32f4 R15: 00007fb62ce4d6d4

Crashes (2):
Time Kernel Commit Syzkaller Config Log Report Syz repro C repro VM info Assets (help?) Manager Title
2020/06/09 13:45 upstream 7ae77150d94d 0d60b78a .config console log report ci-upstream-kasan-gce-selinux-root
2020/06/08 17:00 upstream 7ae77150d94d 7604bb03 .config console log report ci-upstream-kasan-gce-386
* Struck through repros no longer work on HEAD.