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INFO: rcu detected stall in unix_dgram_sendmsg (2)

Status: auto-obsoleted due to no activity on 2023/04/10 02:12
Subsystems: kernel
[Documentation on labels]
First crash: 549d, last: 500d
▶ ▼ Similar bugs (2)
Kernel Title Repro Cause bisect Fix bisect Count Last Reported Patched Status
upstream INFO: rcu detected stall in unix_dgram_sendmsg net 1 685d 685d 0/26 auto-closed as invalid on 2022/09/18 14:12
upstream INFO: rcu detected stall in unix_dgram_sendmsg (3) net 4 218d 354d 0/26 auto-obsoleted due to no activity on 2023/12/29 14:50

Sample crash report:
rcu: INFO: rcu_preempt self-detected stall on CPU
rcu: 	0-...!: (1 GPs behind) idle=767c/1/0x4000000000000000 softirq=90667/90668 fqs=0
	(t=10500 jiffies g=136281 q=283 ncpus=2)
rcu: rcu_preempt kthread timer wakeup didn't happen for 10499 jiffies! g136281 f0x0 RCU_GP_WAIT_FQS(5) ->state=0x402
rcu: 	Possible timer handling issue on cpu=1 timer-softirq=82703
rcu: rcu_preempt kthread starved for 10500 jiffies! g136281 f0x0 RCU_GP_WAIT_FQS(5) ->state=0x402 ->cpu=1
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:I stack:28144 pid:16    ppid:2      flags:0x00004000
Call Trace:
 <TASK>
 context_switch kernel/sched/core.c:5244 [inline]
 __schedule+0xb8a/0x5450 kernel/sched/core.c:6555
 schedule+0xde/0x1b0 kernel/sched/core.c:6631
 schedule_timeout+0x14e/0x2a0 kernel/time/timer.c:2167
 rcu_gp_fqs_loop+0x190/0x910 kernel/rcu/tree.c:1656
 rcu_gp_kthread+0x23a/0x360 kernel/rcu/tree.c:1855
 kthread+0x2e8/0x3a0 kernel/kthread.c:376
 ret_from_fork+0x1f/0x30 arch/x86/entry/entry_64.S:308
 </TASK>
rcu: Stack dump where RCU GP kthread last ran:
Sending NMI from CPU 0 to CPUs 1:
NMI backtrace for cpu 1
CPU: 1 PID: 29243 Comm: syz-executor.1 Not tainted 6.1.0-syzkaller-14446-g8395ae05cb5a #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 10/26/2022
RIP: 0010:native_save_fl arch/x86/include/asm/irqflags.h:29 [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_is_held_type+0x55/0x140 kernel/locking/lockdep.c:5707
Code: fc 75 85 c0 0f 85 ca 00 00 00 65 4c 8b 24 25 00 ac 03 00 41 8b 94 24 34 0a 00 00 85 d2 0f 85 b1 00 00 00 48 89 fd 41 89 f6 9c <8f> 04 24 fa 48 c7 c7 20 4e 4c 8a 31 db e8 a9 15 00 00 41 8b 84 24
RSP: 0018:ffffc900001e0dd0 EFLAGS: 00000046
RAX: 0000000000000000 RBX: 0000000000000001 RCX: 0000000000000001
RDX: 0000000000000000 RSI: 00000000ffffffff RDI: ffffffff8c791700
RBP: ffffffff8c791700 R08: 0000000000000001 R09: 0000000000000000
R10: 0000000000000001 R11: 0000000000000000 R12: ffff88802dbeba80
R13: 00000000ffffffff R14: 00000000ffffffff R15: ffff888055d7a340
FS:  00007fcf3092b700(0000) GS:ffff8880b9900000(0000) knlGS:0000000000000000
CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 00007f31839a7160 CR3: 000000002feb0000 CR4: 0000000000350ee0
Call Trace:
 <IRQ>
 lock_is_held include/linux/lockdep.h:283 [inline]
 rcu_read_lock_sched_held+0x3e/0x70 kernel/rcu/update.c:125
 trace_hrtimer_expire_exit include/trace/events/timer.h:282 [inline]
 __run_hrtimer kernel/time/hrtimer.c:1688 [inline]
 __hrtimer_run_queues+0xb43/0xfb0 kernel/time/hrtimer.c:1749
 hrtimer_interrupt+0x320/0x790 kernel/time/hrtimer.c:1811
 local_apic_timer_interrupt arch/x86/kernel/apic/apic.c:1096 [inline]
 __sysvec_apic_timer_interrupt+0x180/0x640 arch/x86/kernel/apic/apic.c:1113
 sysvec_apic_timer_interrupt+0x92/0xc0 arch/x86/kernel/apic/apic.c:1107
 </IRQ>
 <TASK>
 asm_sysvec_apic_timer_interrupt+0x1a/0x20 arch/x86/include/asm/idtentry.h:649
RIP: 0010:finish_task_switch.isra.0+0x2bf/0xc80 kernel/sched/core.c:5123
Code: 8b 3a 4c 89 e7 48 c7 02 00 00 00 00 ff d1 4d 85 ff 75 bf 4c 89 e7 e8 10 f8 ff ff e8 ab 96 30 00 fb 65 48 8b 1c 25 00 ac 03 00 <48> 8d bb 48 15 00 00 48 b8 00 00 00 00 00 fc ff df 48 89 fa 48 c1
RSP: 0018:ffffc9000ae8f4b0 EFLAGS: 00000202
RAX: 00000000000004ad RBX: ffff88802dbeba80 RCX: 1ffffffff1ce54e9
RDX: 0000000000000000 RSI: 0000000000000001 RDI: 0000000000000000
RBP: ffffc9000ae8f4f8 R08: 0000000000000001 R09: 0000000000000001
R10: ffffed10173276b0 R11: 0000000000000000 R12: ffff8880b993b580
R13: ffff88807e9657c0 R14: 0000000000000000 R15: ffff8880b993bfb8
 context_switch kernel/sched/core.c:5247 [inline]
 __schedule+0xb92/0x5450 kernel/sched/core.c:6555
 schedule+0xde/0x1b0 kernel/sched/core.c:6631
 schedule_timeout+0x1e1/0x2a0 kernel/time/timer.c:2143
 unix_wait_for_peer+0x244/0x280 net/unix/af_unix.c:1449
 unix_dgram_sendmsg+0x19a1/0x1bc0 net/unix/af_unix.c:2047
 sock_sendmsg_nosec net/socket.c:714 [inline]
 sock_sendmsg+0xd3/0x120 net/socket.c:734
 ____sys_sendmsg+0x334/0x8c0 net/socket.c:2476
 ___sys_sendmsg+0x110/0x1b0 net/socket.c:2530
 __sys_sendmmsg+0x18f/0x460 net/socket.c:2616
 __do_sys_sendmmsg net/socket.c:2645 [inline]
 __se_sys_sendmmsg net/socket.c:2642 [inline]
 __x64_sys_sendmmsg+0x9d/0x100 net/socket.c:2642
 do_syscall_x64 arch/x86/entry/common.c:50 [inline]
 do_syscall_64+0x39/0xb0 arch/x86/entry/common.c:80
 entry_SYSCALL_64_after_hwframe+0x63/0xcd
RIP: 0033:0x7fcf2fc8c0a9
Code: 28 00 00 00 75 05 48 83 c4 28 c3 e8 f1 19 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 b8 ff ff ff f7 d8 64 89 01 48
RSP: 002b:00007fcf3092b168 EFLAGS: 00000246 ORIG_RAX: 0000000000000133
RAX: ffffffffffffffda RBX: 00007fcf2fdabf80 RCX: 00007fcf2fc8c0a9
RDX: 0000000000000318 RSI: 00000000200bd000 RDI: 0000000000000004
RBP: 00007fcf2fce7ae9 R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000
R13: 00007ffe41a43daf R14: 00007fcf3092b300 R15: 0000000000022000
 </TASK>
CPU: 0 PID: 29249 Comm: syz-executor.1 Not tainted 6.1.0-syzkaller-14446-g8395ae05cb5a #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 10/26/2022
RIP: 0010:csd_lock_wait kernel/smp.c:413 [inline]
RIP: 0010:smp_call_function_many_cond+0x43f/0x10a0 kernel/smp.c:987
Code: e6 e8 05 fb 0a 00 45 85 e4 74 48 48 8b 04 24 49 89 c5 83 e0 07 49 c1 ed 03 49 89 c4 4d 01 fd 41 83 c4 03 e8 33 fe 0a 00 f3 90 <41> 0f b6 45 00 41 38 c4 7c 08 84 c0 0f 85 4e 0a 00 00 8b 43 08 31
RSP: 0018:ffffc900117df3e8 EFLAGS: 00000246
RAX: 0000000000040000 RBX: ffff8880b9941d60 RCX: ffffc9000b352000
RDX: 0000000000040000 RSI: ffffffff817653ad RDI: 0000000000000005
RBP: 0000000000000001 R08: 0000000000000005 R09: 0000000000000000
R10: 0000000000000001 R11: 0000000000000000 R12: 0000000000000003
R13: ffffed10173283ad R14: 0000000000000001 R15: dffffc0000000000
FS:  00007fcf3090a700(0000) GS:ffff8880b9800000(0000) knlGS:0000000000000000
CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 000000002000d030 CR3: 000000002feb0000 CR4: 0000000000350ef0
Call Trace:
 <TASK>
 on_each_cpu_cond_mask+0x5a/0xa0 kernel/smp.c:1155
 __flush_tlb_multi arch/x86/include/asm/paravirt.h:87 [inline]
 flush_tlb_multi arch/x86/mm/tlb.c:924 [inline]
 flush_tlb_mm_range+0x333/0x4d0 arch/x86/mm/tlb.c:1010
 flush_tlb_page arch/x86/include/asm/tlbflush.h:240 [inline]
 ptep_clear_flush+0x12f/0x160 mm/pgtable-generic.c:98
 wp_page_copy mm/memory.c:3156 [inline]
 do_wp_page+0x112e/0x3370 mm/memory.c:3447
 handle_pte_fault mm/memory.c:4949 [inline]
 __handle_mm_fault+0x1f58/0x3c90 mm/memory.c:5073
 handle_mm_fault+0x1b6/0x850 mm/memory.c:5219
 do_user_addr_fault+0x475/0x1210 arch/x86/mm/fault.c:1428
 handle_page_fault arch/x86/mm/fault.c:1519 [inline]
 exc_page_fault+0x98/0x170 arch/x86/mm/fault.c:1575
 asm_exc_page_fault+0x26/0x30 arch/x86/include/asm/idtentry.h:570
RIP: 0010:__put_user_nocheck_4+0xb/0x20 arch/x86/lib/putuser.S:105
Code: 0f 1e fa 48 bb fd ef ff ff ff 7f 00 00 48 39 d9 73 70 0f 01 cb 89 01 31 c9 0f 01 ca c3 66 90 f3 0f 1e fa f3 0f 1e fa 0f 01 cb <89> 01 31 c9 0f 01 ca c3 66 66 2e 0f 1f 84 00 00 00 00 00 66 90 f3
RSP: 0018:ffffc900117dfa00 EFLAGS: 00050212
RAX: 0000000000000000 RBX: ffffc900117dfdf4 RCX: 000000002000d030
RDX: 0000000000040000 RSI: ffffffff87be6b4f RDI: 0000000000000005
RBP: ffffc900117dfdb0 R08: 0000000000000005 R09: 0000000000000000
R10: 0000000000000002 R11: 0000000000000000 R12: 0000000000000000
R13: 0000000000000002 R14: 000000002000d030 R15: 0000000000000000
 ____sys_recvmsg+0x3ba/0x610 net/socket.c:2708
 ___sys_recvmsg+0xf2/0x180 net/socket.c:2737
 do_recvmmsg+0x25e/0x6e0 net/socket.c:2831
 __sys_recvmmsg net/socket.c:2910 [inline]
 __do_sys_recvmmsg net/socket.c:2933 [inline]
 __se_sys_recvmmsg net/socket.c:2926 [inline]
 __x64_sys_recvmmsg+0x20f/0x260 net/socket.c:2926
 do_syscall_x64 arch/x86/entry/common.c:50 [inline]
 do_syscall_64+0x39/0xb0 arch/x86/entry/common.c:80
 entry_SYSCALL_64_after_hwframe+0x63/0xcd
RIP: 0033:0x7fcf2fc8c0a9
Code: 28 00 00 00 75 05 48 83 c4 28 c3 e8 f1 19 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 b8 ff ff ff f7 d8 64 89 01 48
RSP: 002b:00007fcf3090a168 EFLAGS: 00000246 ORIG_RAX: 000000000000012b
RAX: ffffffffffffffda RBX: 00007fcf2fdac050 RCX: 00007fcf2fc8c0a9
RDX: 0000000000010106 RSI: 00000000200000c0 RDI: 0000000000000003
RBP: 00007fcf2fce7ae9 R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000002 R11: 0000000000000246 R12: 0000000000000000
R13: 00007ffe41a43daf R14: 00007fcf3090a300 R15: 0000000000022000
 </TASK>

Crashes (2):
Time Kernel Commit Syzkaller Config Log Report Syz repro C repro VM info Assets (help?) Manager Title
2022/12/23 01:17 upstream 8395ae05cb5a 9da18ae8 .config console log report info [disk image] [vmlinux] [kernel image] ci-upstream-kasan-gce-root INFO: rcu detected stall in unix_dgram_sendmsg
2022/11/04 10:00 https://git.kernel.org/pub/scm/linux/kernel/git/gregkh/usb.git usb-testing a8bc8cc193c6 6d752409 .config console log report info [disk image] [vmlinux] [kernel image] ci2-upstream-usb INFO: rcu detected stall in unix_dgram_sendmsg
* Struck through repros no longer work on HEAD.