BUG: soft lockup in rcu_is

Kernel	Title	Repro	Cause bisect	Fix bisect	Count	Last	Reported	Patched	Status
linux-4.19	BUG: soft lockup in rcu_is_watching				2	1126d	1133d	0/1	auto-closed as invalid on 2022/03/04 02:38
watchdog: BUG: soft lockup - CPU#0 stuck for 22s! [syz-executor.1:18297]
Modules linked in:
irq event stamp: 3646923
hardirqs last  enabled at (3646922): [<ffffffff81003ce4>] trace_hardirqs_on_thunk+0x1a/0x1c
hardirqs last disabled at (3646923): [<ffffffff81003d00>] trace_hardirqs_off_thunk+0x1a/0x1c
softirqs last  enabled at (3629860): [<ffffffff88400678>] __do_softirq+0x678/0x980 kernel/softirq.c:318
softirqs last disabled at (3629863): [<ffffffff813927d5>] invoke_softirq kernel/softirq.c:372 [inline]
softirqs last disabled at (3629863): [<ffffffff813927d5>] irq_exit+0x215/0x260 kernel/softirq.c:412
CPU: 0 PID: 18297 Comm: syz-executor.1 Not tainted 4.19.211-syzkaller #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 09/22/2022
RIP: 0010:__sanitizer_cov_trace_pc+0x0/0x50 kernel/kcov.c:97
Code: ff 48 89 df e8 11 dd 35 00 e9 ab fe ff ff 4c 89 ef e8 04 dd 35 00 e9 23 fe ff ff 90 90 90 90 90 90 90 90 90 90 90 90 90 90 90 <48> 8b 34 24 65 48 8b 04 25 c0 df 01 00 65 8b 15 cc 59 9f 7e 81 e2
RSP: 0018:ffff8880ba007cb0 EFLAGS: 00000206 ORIG_RAX: ffffffffffffff13
RAX: ffff8880184b2280 RBX: 0000000000000103 RCX: ffffffff83771e23
RDX: 0000000000000100 RSI: ffffffff83771e2c RDI: 0000000000000005
RBP: ffffffff88b3e120 R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000005 R11: 0000000000000000 R12: 0000000000000000
R13: ffffffff88b3e0e0 R14: 0000000000000000 R15: 0000000000000000
ieee802154 phy0 wpan0: encryption failed: -22
FS:  00007f93a3d74700(0000) GS:ffff8880ba000000(0000) knlGS:0000000000000000
CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
ieee802154 phy1 wpan1: encryption failed: -22
CR2: 00007f7f63045000 CR3: 0000000096b44000 CR4: 00000000003406f0
DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000
DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400
Call Trace:
 <IRQ>
 check_preemption_disabled+0x41/0x280 lib/smp_processor_id.c:51
 rcu_dynticks_curr_cpu_in_eqs kernel/rcu/tree.c:348 [inline]
 rcu_is_watching+0x12/0xc0 kernel/rcu/tree.c:1025
 rcu_read_lock_sched_held+0xc6/0x1d0 kernel/rcu/update.c:113
 trace_timer_expire_exit include/trace/events/timer.h:121 [inline]
 call_timer_fn+0x617/0x700 kernel/time/timer.c:1339
 expire_timers+0x243/0x4e0 kernel/time/timer.c:1375
 __run_timers kernel/time/timer.c:1696 [inline]
 run_timer_softirq+0x21c/0x670 kernel/time/timer.c:1709
 __do_softirq+0x265/0x980 kernel/softirq.c:292
 invoke_softirq kernel/softirq.c:372 [inline]
 irq_exit+0x215/0x260 kernel/softirq.c:412
 exiting_irq arch/x86/include/asm/apic.h:536 [inline]
 smp_apic_timer_interrupt+0x136/0x550 arch/x86/kernel/apic/apic.c:1098
 apic_timer_interrupt+0xf/0x20 arch/x86/entry/entry_64.S:894
 </IRQ>
RIP: 0010:__list_del include/linux/list.h:105 [inline]
RIP: 0010:__list_del_entry include/linux/list.h:120 [inline]
RIP: 0010:list_del_init include/linux/list.h:159 [inline]
RIP: 0010:unhash_mnt+0xe9/0x470 fs/namespace.c:802
Code: 8d 6b 68 4c 8b 73 60 48 b8 00 00 00 00 00 fc ff df 4c 89 ea 48 c1 ea 03 80 3c 02 00 0f 85 32 03 00 00 49 8d 7e 08 4c 8b 63 68 <48> b8 00 00 00 00 00 fc ff df 48 89 fa 48 c1 ea 03 80 3c 02 00 0f
RSP: 0018:ffff888094e57918 EFLAGS: 00000246 ORIG_RAX: ffffffffffffff13
RAX: dffffc0000000000 RBX: ffff8880aa3cf200 RCX: ffffffff81aa7345
RDX: 1ffff11015479e4d RSI: ffffffff81aa7353 RDI: ffff8880aa3cf268
RBP: ffff8880aa3cf260 R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000001 R11: 0000000000000000 R12: ffff8880aa3cf260
R13: ffff8880aa3cf268 R14: ffff8880aa3cf260 R15: ffff8880aa3cf210
 umount_mnt fs/namespace.c:826 [inline]
 umount_tree+0x928/0xc80 fs/namespace.c:1460
 drop_collected_mounts+0xa6/0x1a0 fs/namespace.c:1806
 put_mnt_ns fs/namespace.c:3271 [inline]
 put_mnt_ns+0x5f/0x80 fs/namespace.c:3267
 free_nsproxy+0x41/0x220 kernel/nsproxy.c:176
 switch_task_namespaces+0xaa/0xc0 kernel/nsproxy.c:229
 do_exit+0xbee/0x2be0 kernel/exit.c:869
 do_group_exit+0x125/0x310 kernel/exit.c:967
 get_signal+0x3f2/0x1f70 kernel/signal.c:2589
 do_signal+0x8f/0x1670 arch/x86/kernel/signal.c:799
 exit_to_usermode_loop+0x204/0x2a0 arch/x86/entry/common.c:163
 prepare_exit_to_usermode arch/x86/entry/common.c:198 [inline]
 syscall_return_slowpath arch/x86/entry/common.c:271 [inline]
 do_syscall_64+0x538/0x620 arch/x86/entry/common.c:296
 entry_SYSCALL_64_after_hwframe+0x49/0xbe
RIP: 0033:0x7f93a54005a9
Code: Bad RIP value.
RSP: 002b:00007f93a3d74168 EFLAGS: 00000246 ORIG_RAX: 0000000000000110
RAX: 0000000000000000 RBX: 00007f93a5521f80 RCX: 00007f93a54005a9
RDX: 0000000000000000 RSI: 0000000000000000 RDI: 0000000000020000
RBP: 00007f93a545b580 R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000
R13: 00007fff2d7280af R14: 00007f93a3d74300 R15: 0000000000022000
Sending NMI from CPU 0 to CPUs 1:
NMI backtrace for cpu 1
CPU: 1 PID: 8173 Comm: syz-executor.4 Not tainted 4.19.211-syzkaller #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 09/22/2022
RIP: 0010:write_comp_data+0x23/0x70 kernel/kcov.c:122
Code: 1f 84 00 00 00 00 00 49 89 f1 49 89 fa 65 48 8b 34 25 c0 df 01 00 65 8b 05 7a 59 9f 7e a9 00 01 1f 00 75 4f 8b 86 60 13 00 00 <83> f8 03 75 44 48 8b 86 68 13 00 00 8b b6 64 13 00 00 48 8b 38 48
RSP: 0018:ffff888093197ae0 EFLAGS: 00000246
RAX: 0000000000000000 RBX: 0000000000000040 RCX: ffffffff81a604bc
RDX: 0000000000000001 RSI: ffff888091802480 RDI: 0000000000000001
RBP: ffff888093197b70 R08: ffffffff8cd41398 R09: 0000000000000000
R10: 0000000000000001 R11: 0000000000000000 R12: ffff888093197c78
R13: ffffffff89f18280 R14: 0000000000000001 R15: 000000000000d1ed
FS:  00005555565d6400(0000) GS:ffff8880ba100000(0000) knlGS:0000000000000000
CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 000000000083ed28 CR3: 000000009fa6b000 CR4: 00000000003406e0
DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000
DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400
Call Trace:
 __read_seqcount_begin include/linux/seqlock.h:114 [inline]
 raw_read_seqcount_begin include/linux/seqlock.h:148 [inline]
 read_seqcount_begin include/linux/seqlock.h:165 [inline]
 read_seqbegin include/linux/seqlock.h:440 [inline]
 path_init+0x129c/0x19d0 fs/namei.c:2206
 path_mountpoint+0x84/0xac0 fs/namei.c:2692
 filename_mountpoint+0x184/0x4f0 fs/namei.c:2718
 ksys_umount+0x156/0x1070 fs/namespace.c:1654
 __do_sys_umount fs/namespace.c:1680 [inline]
 __se_sys_umount fs/namespace.c:1678 [inline]
 __x64_sys_umount+0x50/0x70 fs/namespace.c:1678
 do_syscall_64+0xf9/0x620 arch/x86/entry/common.c:293
 entry_SYSCALL_64_after_hwframe+0x49/0xbe
RIP: 0033:0x7ff2d3301a17
Code: ff ff ff f7 d8 64 89 01 48 83 c8 ff c3 66 0f 1f 44 00 00 31 f6 e9 09 00 00 00 66 0f 1f 84 00 00 00 00 00 b8 a6 00 00 00 0f 05 <48> 3d 01 f0 ff ff 73 01 c3 48 c7 c1 b8 ff ff ff f7 d8 64 89 01 48
RSP: 002b:00007fff8c7fcde8 EFLAGS: 00000246 ORIG_RAX: 00000000000000a6
RAX: ffffffffffffffda RBX: 0000000000001bd4 RCX: 00007ff2d3301a17
RDX: 000000000000000c RSI: 000000000000000a RDI: 00007fff8c7fdf70
RBP: 00007fff8c7fdf4c R08: 0000000000000000 R09: 0000012eefb00a58
R10: 0000000000000000 R11: 0000000000000246 R12: 00007ff2d335a5f6
R13: 00007fff8c7fdf70 R14: 0000000000000000 R15: 00007fff8c7fdfb0