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INFO: rcu detected stall in batadv_bla_periodic_work

Status: upstream: reported on 2024/11/08 00:06
Reported-by: syzbot+6775dc938accd4171f4b@syzkaller.appspotmail.com
First crash: 26d, last: 26d
▶ ▼ Similar bugs (3)
Kernel Title Repro Cause bisect Fix bisect Count Last Reported Patched Status
upstream INFO: rcu detected stall in batadv_bla_periodic_work net 1 389d 389d 0/28 auto-obsoleted due to no activity on 2024/02/09 07:47
linux-5.15 INFO: rcu detected stall in batadv_bla_periodic_work 1 42d 42d 0/3 upstream: reported on 2024/10/22 13:50
upstream INFO: rcu detected stall in batadv_bla_periodic_work (2) batman syz error 1 50d 77d 0/28 upstream: reported syz repro on 2024/09/17 15:14

Sample crash report:
rcu: INFO: rcu_preempt detected stalls on CPUs/tasks:
rcu: 	1-...!: (1 GPs behind) idle=dbdc/1/0x4000000000000000 softirq=29035/29037 fqs=7
	(detected by 0, t=10505 jiffies, g=36405, q=578 ncpus=2)
Sending NMI from CPU 0 to CPUs 1:
NMI backtrace for cpu 1
CPU: 1 PID: 7221 Comm: kworker/u4:9 Not tainted 6.1.115-syzkaller #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 09/13/2024
Workqueue: bat_events batadv_bla_periodic_work
RIP: 0010:native_save_fl arch/x86/include/asm/irqflags.h:22 [inline]
RIP: 0010:arch_local_save_flags arch/x86/include/asm/irqflags.h:70 [inline]
RIP: 0010:arch_local_irq_save arch/x86/include/asm/irqflags.h:106 [inline]
RIP: 0010:lock_acquire+0x171/0x5a0 kernel/locking/lockdep.c:5658
Code: d8 48 c1 e8 03 42 0f b6 04 28 84 c0 0f 85 ea 02 00 00 83 3b 00 0f 85 5c 01 00 00 4c 8d bc 24 80 00 00 00 4c 89 fb 48 c1 eb 03 <42> 80 3c 2b 00 74 08 4c 89 ff e8 c0 7c 77 00 48 c7 84 24 80 00 00
RSP: 0018:ffffc900001e0b60 EFLAGS: 00000802
RAX: 0000000000000000 RBX: 1ffff9200003c17c RCX: ffffffff816a995b
RDX: 0000000000000000 RSI: ffffffff8b5d7520 RDI: ffffffff8b5d74e0
RBP: ffffc900001e0ca8 R08: dffffc0000000000 R09: fffffbfff1d34076
R10: 0000000000000000 R11: dffffc0000000001 R12: 1ffff9200003c174
R13: dffffc0000000000 R14: 0000000000000000 R15: ffffc900001e0be0
FS:  0000000000000000(0000) GS:ffff8880b8f00000(0000) knlGS:0000000000000000
CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 00007f9edb801866 CR3: 000000000d08e000 CR4: 00000000003506e0
DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000
DR3: 00000000e08e000e DR6: 00000000ffff0ff0 DR7: 0000000000000400
Call Trace:
 <NMI>
 </NMI>
 <IRQ>
 rcu_lock_acquire include/linux/rcupdate.h:350 [inline]
 rcu_read_lock include/linux/rcupdate.h:791 [inline]
 advance_sched+0x6ec/0x970 net/sched/sch_taprio.c:753
 __run_hrtimer kernel/time/hrtimer.c:1689 [inline]
 __hrtimer_run_queues+0x5e5/0xe50 kernel/time/hrtimer.c:1753
 hrtimer_interrupt+0x392/0x980 kernel/time/hrtimer.c:1815
 local_apic_timer_interrupt arch/x86/kernel/apic/apic.c:1107 [inline]
 __sysvec_apic_timer_interrupt+0x158/0x5b0 arch/x86/kernel/apic/apic.c:1124
 instr_sysvec_apic_timer_interrupt arch/x86/kernel/apic/apic.c:1118 [inline]
 sysvec_apic_timer_interrupt+0x9b/0xc0 arch/x86/kernel/apic/apic.c:1118
 </IRQ>
 <TASK>
 asm_sysvec_apic_timer_interrupt+0x16/0x20 arch/x86/include/asm/idtentry.h:691
RIP: 0010:lock_acquire+0x26f/0x5a0 kernel/locking/lockdep.c:5666
Code: 2b 00 74 08 4c 89 f7 e8 6f 7b 77 00 f6 44 24 61 02 0f 85 84 01 00 00 41 f7 c7 00 02 00 00 74 01 fb 48 c7 44 24 40 0e 36 e0 45 <4b> c7 44 25 00 00 00 00 00 43 c7 44 25 09 00 00 00 00 43 c7 44 25
RSP: 0018:ffffc9000386f940 EFLAGS: 00000206
RAX: 0000000000000001 RBX: 1ffff9200070df34 RCX: 1ffff9200070ded4
RDX: dffffc0000000000 RSI: ffffffff8b0c1440 RDI: ffffffff8b5d7540
RBP: ffffc9000386fa88 R08: dffffc0000000000 R09: fffffbfff224604d
R10: 0000000000000000 R11: dffffc0000000001 R12: 1ffff9200070df30
R13: dffffc0000000000 R14: ffffc9000386f9a0 R15: 0000000000000246
 rcu_lock_acquire include/linux/rcupdate.h:350 [inline]
 rcu_read_lock include/linux/rcupdate.h:791 [inline]
 batadv_bla_purge_claims+0x11d/0x6c0 net/batman-adv/bridge_loop_avoidance.c:1289
 batadv_bla_periodic_work+0xb1/0xae0 net/batman-adv/bridge_loop_avoidance.c:1444
 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:295
 </TASK>
rcu: rcu_preempt kthread starved for 10465 jiffies! g36405 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:5241 [inline]
 __schedule+0x143f/0x4570 kernel/sched/core.c:6558
 schedule+0xbf/0x180 kernel/sched/core.c:6634
 schedule_timeout+0x1b9/0x300 kernel/time/timer.c:1965
 rcu_gp_fqs_loop+0x2d2/0x1150 kernel/rcu/tree.c:1706
 rcu_gp_kthread+0xa3/0x3b0 kernel/rcu/tree.c:1905
 kthread+0x28d/0x320 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: 8382 Comm: syz.6.1463 Not tainted 6.1.115-syzkaller #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 09/13/2024
RIP: 0010:csd_lock_wait kernel/smp.c:424 [inline]
RIP: 0010:smp_call_function_many_cond+0x1fae/0x3460 kernel/smp.c:998
Code: 2f 44 89 ee 83 e6 01 31 ff e8 ae 43 0b 00 41 83 e5 01 49 bd 00 00 00 00 00 fc ff df 75 0a e8 39 40 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:ffffc900035279c0 EFLAGS: 00000246
RAX: ffffffff817f5339 RBX: 1ffff110171e81b1 RCX: 0000000000040000
RDX: ffffc9000c669000 RSI: 000000000003ffff RDI: 0000000000040000
RBP: ffffc90003527d88 R08: ffffffff817f5302 R09: fffffbfff224606d
R10: 0000000000000000 R11: dffffc0000000001 R12: 0000000800000000
R13: dffffc0000000000 R14: 0000000000000001 R15: ffff8880b8f40d88
FS:  00007f89149f86c0(0000) GS:ffff8880b8e00000(0000) knlGS:0000000000000000
CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 00007fff098ddf28 CR3: 00000000666fc000 CR4: 00000000003526f0
DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000
DR3: 00000000e08e000e DR6: 00000000ffff0ff0 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]
 hardware_enable_all+0x77/0x120 virt/kvm/kvm_main.c:5164
 kvm_create_vm virt/kvm/kvm_main.c:1223 [inline]
 kvm_dev_ioctl_create_vm virt/kvm/kvm_main.c:5010 [inline]
 kvm_dev_ioctl+0x10db/0x1860 virt/kvm/kvm_main.c:5052
 vfs_ioctl fs/ioctl.c:51 [inline]
 __do_sys_ioctl fs/ioctl.c:870 [inline]
 __se_sys_ioctl+0xf1/0x160 fs/ioctl.c:856
 do_syscall_x64 arch/x86/entry/common.c:51 [inline]
 do_syscall_64+0x3b/0xb0 arch/x86/entry/common.c:81
 entry_SYSCALL_64_after_hwframe+0x68/0xd2
RIP: 0033:0x7f8913b7e719
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:00007f89149f8038 EFLAGS: 00000246 ORIG_RAX: 0000000000000010
RAX: ffffffffffffffda RBX: 00007f8913d35f80 RCX: 00007f8913b7e719
RDX: 0000000000000000 RSI: 000000000000ae01 RDI: 0000000000000003
RBP: 00007f8913bf139e R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000
R13: 0000000000000000 R14: 00007f8913d35f80 R15: 00007ffd514b9068
 </TASK>

Crashes (1):
Time Kernel Commit Syzkaller Config Log Report Syz repro C repro VM info Assets (help?) Manager Title
2024/11/08 00:06 linux-6.1.y 7c15117f9468 867e44df .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-6-1-kasan INFO: rcu detected stall in batadv_bla_periodic_work
* Struck through repros no longer work on HEAD.