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INFO: rcu detected stall in sys_recvmmsg (2)

Status: upstream: reported on 2024/04/05 00:00
Reported-by: syzbot+21ec4549d7d2c6bf9a0b@syzkaller.appspotmail.com
First crash: 113d, last: 53d
▶ ▼ Similar bugs (7)
Kernel Title Repro Cause bisect Fix bisect Count Last Reported Patched Status
upstream INFO: rcu detected stall in sys_recvmmsg (3) net 42 21d 220d 0/27 upstream: reported on 2023/12/19 09:31
linux-4.19 INFO: rcu detected stall in sys_recvmmsg C error 1 582d 582d 0/1 upstream: reported C repro on 2022/12/23 04:58
linux-5.15 INFO: rcu detected stall in sys_recvmmsg origin:upstream C 10 9d19h 478d 0/3 upstream: reported C repro on 2023/04/06 01:32
upstream INFO: rcu detected stall in sys_recvmmsg mptcp C done 52 907d 1039d 20/27 fixed on 2022/03/08 16:11
linux-6.1 INFO: rcu detected stall in sys_recvmmsg 5 359d 490d 0/3 auto-obsoleted due to no activity on 2023/11/11 06:06
upstream INFO: rcu detected stall in sys_recvmmsg (2) net 4 668d 698d 0/27 auto-obsoleted due to no activity on 2023/01/03 09:53
android-5-15 BUG: soft lockup in sys_recvmmsg 5 1d21h 94d 0/2 premoderation: reported on 2024/04/23 17:26

Sample crash report:
rcu: INFO: rcu_preempt detected stalls on CPUs/tasks:
rcu: 	Tasks blocked on level-0 rcu_node (CPUs 0-1): P7302/1:b..l
	(detected by 1, t=11223 jiffies, g=25649, q=640 ncpus=2)
task:syz-executor.0  state:R  running task     stack:28104 pid:7302  ppid:6719   flags:0x00004006
Call Trace:
 <TASK>
 context_switch kernel/sched/core.c:5245 [inline]
 __schedule+0x142d/0x4550 kernel/sched/core.c:6558
 preempt_schedule_common+0x83/0xd0 kernel/sched/core.c:6727
 preempt_schedule+0xd9/0xe0 kernel/sched/core.c:6751
 preempt_schedule_thunk+0x16/0x18 arch/x86/entry/thunk_64.S:34
 __raw_spin_unlock include/linux/spinlock_api_smp.h:143 [inline]
 _raw_spin_unlock+0x36/0x40 kernel/locking/spinlock.c:186
 spin_unlock include/linux/spinlock.h:391 [inline]
 filemap_map_pages+0xffa/0x12c0 mm/filemap.c:3470
 do_fault_around mm/memory.c:4581 [inline]
 do_read_fault mm/memory.c:4607 [inline]
 do_fault mm/memory.c:4741 [inline]
 handle_pte_fault mm/memory.c:5013 [inline]
 __handle_mm_fault mm/memory.c:5155 [inline]
 handle_mm_fault+0x33e2/0x5340 mm/memory.c:5276
 do_user_addr_fault arch/x86/mm/fault.c:1371 [inline]
 handle_page_fault arch/x86/mm/fault.c:1462 [inline]
 exc_page_fault+0x26f/0x660 arch/x86/mm/fault.c:1518
 asm_exc_page_fault+0x22/0x30 arch/x86/include/asm/idtentry.h:570
RIP: 0033:0x7f16a0296ef0
RSP: 002b:00007ffeb1ab0d28 EFLAGS: 00010216
RAX: 0000000000000020 RBX: 00007ffeb1ab1290 RCX: 0000000000000000
RDX: 000000000000000a RSI: 00007ffeb1ab1238 RDI: 0000000000000000
RBP: 0000000000000016 R08: 0000000000000000 R09: 0000000000000000
R10: 00000000ffffffff R11: 0000000000000001 R12: 0000000000000075
R13: 00007ffeb1ab1410 R14: 00007ffeb1ab1238 R15: 0000000000000000
 </TASK>
rcu: rcu_preempt kthread timer wakeup didn't happen for 9761 jiffies! g25649 f0x0 RCU_GP_WAIT_FQS(5) ->state=0x402
rcu: 	Possible timer handling issue on cpu=0 timer-softirq=12521
rcu: rcu_preempt kthread starved for 9762 jiffies! g25649 f0x0 RCU_GP_WAIT_FQS(5) ->state=0x402 ->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:I stack:26136 pid:16    ppid:2      flags:0x00004000
Call Trace:
 <TASK>
 context_switch kernel/sched/core.c:5245 [inline]
 __schedule+0x142d/0x4550 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:308
 </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 PID: 7227 Comm: syz-executor.1 Not tainted 6.1.92-syzkaller #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 04/02/2024
RIP: 0010:mark_usage kernel/locking/lockdep.c:4501 [inline]
RIP: 0010:__lock_acquire+0x9da/0x1f80 kernel/locking/lockdep.c:5003
Code: 24 48 c7 c0 28 be 73 8e 48 c1 e8 03 0f b6 04 10 84 c0 0f 85 0d 12 00 00 83 3d 79 4c 09 0d 00 0f 84 bd 09 00 00 83 7c 24 60 00 <48> 8b 6c 24 20 0f 84 75 02 00 00 41 0f b6 04 17 84 c0 0f 85 47 0e
RSP: 0018:ffffc90000007a60 EFLAGS: 00000002
RAX: ffff88802118a898 RBX: ffff88802118a884 RCX: 0000000000000002
RDX: dffffc0000000000 RSI: ffff88802118a8a0 RDI: ffffffff9049c3c0
RBP: 00000000ffffffff R08: dffffc0000000000 R09: fffffbfff2093879
R10: 0000000000000000 R11: dffffc0000000001 R12: ffff88802118a898
R13: ffff888021189dc0 R14: ffff88802118a8c0 R15: 1ffff11004231518
FS:  00007efd4ddd56c0(0000) GS:ffff8880b9800000(0000) knlGS:0000000000000000
CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 00000000206b1030 CR3: 000000005bbb5000 CR4: 00000000003506f0
DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000
DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400
Call Trace:
 <NMI>
 </NMI>
 <IRQ>
 lock_acquire+0x1f8/0x5a0 kernel/locking/lockdep.c:5662
 __raw_spin_lock include/linux/spinlock_api_smp.h:133 [inline]
 _raw_spin_lock+0x2a/0x40 kernel/locking/spinlock.c:154
 spin_lock include/linux/spinlock.h:351 [inline]
 advance_sched+0x47/0x970 net/sched/sch_taprio.c:700
 __run_hrtimer kernel/time/hrtimer.c:1686 [inline]
 __hrtimer_run_queues+0x5e5/0xe50 kernel/time/hrtimer.c:1750
 hrtimer_interrupt+0x392/0x980 kernel/time/hrtimer.c:1812
 local_apic_timer_interrupt arch/x86/kernel/apic/apic.c:1095 [inline]
 __sysvec_apic_timer_interrupt+0x156/0x580 arch/x86/kernel/apic/apic.c:1112
 sysvec_apic_timer_interrupt+0x8c/0xb0 arch/x86/kernel/apic/apic.c:1106
 </IRQ>
 <TASK>
 asm_sysvec_apic_timer_interrupt+0x16/0x20 arch/x86/include/asm/idtentry.h:653
RIP: 0010:__raw_spin_unlock_irqrestore include/linux/spinlock_api_smp.h:152 [inline]
RIP: 0010:_raw_spin_unlock_irqrestore+0xd4/0x130 kernel/locking/spinlock.c:194
Code: 9c 8f 44 24 20 42 80 3c 23 00 74 08 4c 89 f7 e8 f2 c1 4c f7 f6 44 24 21 02 75 4e 41 f7 c7 00 02 00 00 74 01 fb bf 01 00 00 00 <e8> d7 08 c9 f6 65 8b 05 48 24 6d 75 85 c0 74 3f 48 c7 04 24 0e 36
RSP: 0018:ffffc9000a1975e0 EFLAGS: 00000206
RAX: 3cfbfc2d4044b300 RBX: 1ffff92001432ec0 RCX: ffffffff91c94103
RDX: dffffc0000000000 RSI: ffffffff8aec01c0 RDI: 0000000000000001
RBP: ffffc9000a197670 R08: dffffc0000000000 R09: ffffed10031584aa
R10: 0000000000000000 R11: dffffc0000000001 R12: dffffc0000000000
R13: 1ffff92001432ebc R14: ffffc9000a197600 R15: 0000000000000246
 spin_unlock_irqrestore include/linux/spinlock.h:406 [inline]
 __wake_up_common_lock kernel/sched/wait.c:140 [inline]
 __wake_up+0x128/0x1c0 kernel/sched/wait.c:160
 netlink_rcv_wake net/netlink/af_netlink.c:369 [inline]
 netlink_recvmsg+0xc10/0x1180 net/netlink/af_netlink.c:1965
 ____sys_recvmsg+0x285/0x530
 ___sys_recvmsg net/socket.c:2775 [inline]
 do_recvmmsg+0x46d/0xad0 net/socket.c:2869
 __sys_recvmmsg net/socket.c:2948 [inline]
 __do_sys_recvmmsg net/socket.c:2971 [inline]
 __se_sys_recvmmsg net/socket.c:2964 [inline]
 __x64_sys_recvmmsg+0x195/0x240 net/socket.c:2964
 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: 0033:0x7efd4f27cee9
Code: 28 00 00 00 75 05 48 83 c4 28 c3 e8 e1 20 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 b0 ff ff ff f7 d8 64 89 01 48
RSP: 002b:00007efd4ddd50c8 EFLAGS: 00000246 ORIG_RAX: 000000000000012b
RAX: ffffffffffffffda RBX: 00007efd4f3b4070 RCX: 00007efd4f27cee9
RDX: 03ffffffffffff81 RSI: 0000000020000780 RDI: 0000000000000005
RBP: 00007efd4f2c947f R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000002 R11: 0000000000000246 R12: 0000000000000000
R13: 000000000000006e R14: 00007efd4f3b4070 R15: 00007fffb42eff48
 </TASK>

Crashes (3):
Time Kernel Commit Syzkaller Config Log Report Syz repro C repro VM info Assets (help?) Manager Title
2024/06/03 15:53 linux-6.1.y 88690811da69 0aba2352 .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-6-1-kasan INFO: rcu detected stall in sys_recvmmsg
2024/05/27 21:54 linux-6.1.y 88690811da69 761766e6 .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-6-1-kasan INFO: rcu detected stall in sys_recvmmsg
2024/04/04 23:59 linux-6.1.y 347385861c50 0ee3535e .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-6-1-kasan INFO: rcu detected stall in sys_recvmmsg
* Struck through repros no longer work on HEAD.