rcu: INFO: rcu_preempt detected stalls on CPUs/tasks:
rcu: Tasks blocked on level-0 rcu_node (CPUs 0-1): P29/2:b..l P6429/1:b..l P5794/1:b..l
rcu: (detected by 0, t=10502 jiffies, g=13593, q=12967 ncpus=2)
task:syz-executor state:D stack:22624 pid:5794 tgid:5794 ppid:1 task_flags:0x400140 flags:0x00080002
Call Trace:
context_switch kernel/sched/core.c:5298 [inline]
__schedule+0x1553/0x5240 kernel/sched/core.c:6911
__schedule_loop kernel/sched/core.c:6993 [inline]
schedule_rtlock+0x30/0x70 kernel/sched/core.c:7072
rtlock_slowlock_locked+0x3638/0x3c80 kernel/locking/rtmutex.c:1868
rtlock_slowlock kernel/locking/rtmutex.c:1895 [inline]
rtlock_lock kernel/locking/spinlock_rt.c:43 [inline]
__rt_spin_lock kernel/locking/spinlock_rt.c:49 [inline]
rt_spin_lock+0x165/0x400 kernel/locking/spinlock_rt.c:57
spin_lock_bh include/linux/spinlock_rt.h:90 [inline]
hrtimer_cancel_wait_running+0xfa/0x180 kernel/time/hrtimer.c:1461
hrtimer_cancel kernel/time/hrtimer.c:1492 [inline]
do_nanosleep+0x239/0x660 kernel/time/hrtimer.c:2126
hrtimer_nanosleep+0x20c/0x440 kernel/time/hrtimer.c:2171
__do_sys_clock_nanosleep kernel/time/posix-timers.c:1391 [inline]
__se_sys_clock_nanosleep+0x35b/0x3b0 kernel/time/posix-timers.c:1368
do_syscall_x64 arch/x86/entry/syscall_64.c:63 [inline]
do_syscall_64+0x14d/0xf80 arch/x86/entry/syscall_64.c:94
entry_SYSCALL_64_after_hwframe+0x77/0x7f
RIP: 0033:0x7f62e5d5d04e
RSP: 002b:00007fff2fd5aac8 EFLAGS: 00000246 ORIG_RAX: 00000000000000e6
RAX: ffffffffffffffda RBX: 000055555dd7b500 RCX: 00007f62e5d5d04e
RDX: 00007fff2fd5ab20 RSI: 0000000000000000 RDI: 0000000000000000
RBP: 00007fff2fd5ab8c R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000001388
R13: 00000000000927c0 R14: 000000000002cf68 R15: 00007fff2fd5abe0
task:syz.2.129 state:R running task stack:27904 pid:6429 tgid:6418 ppid:5793 task_flags:0x400040 flags:0x00080002
Call Trace:
context_switch kernel/sched/core.c:5298 [inline]
__schedule+0x1553/0x5240 kernel/sched/core.c:6911
preempt_schedule_irq+0x4d/0xa0 kernel/sched/core.c:7238
irqentry_exit+0x599/0x620 kernel/entry/common.c:239
asm_sysvec_apic_timer_interrupt+0x1a/0x20 arch/x86/include/asm/idtentry.h:697
RIP: 0010:lock_release+0x2d7/0x3d0 kernel/locking/lockdep.c:5893
Code: 7c ae 10 00 00 00 00 eb b5 e8 55 58 83 09 f7 c3 00 02 00 00 74 b9 65 48 8b 05 c5 35 ae 10 48 3b 44 24 28 75 44 fb 48 83 c4 30 <5b> 41 5c 41 5d 41 5e 41 5f 5d c3 cc cc cc cc cc 48 8d 3d 22 27 cd
RSP: 0018:ffffc90006427640 EFLAGS: 00000282
RAX: 044baa2c00cba100 RBX: 0000000000000206 RCX: 0000000000000046
RDX: 00000000c45bc6bf RSI: ffffffff8d7c0dbe RDI: ffffffff8ba67680
RBP: ffff88801ff8c8e0 R08: ffffffff8b2611d0 R09: ffffffff8ddcb9c0
R10: 0000000000000000 R11: ffffed1006db4895 R12: 0000000000000002
R13: 0000000000000002 R14: ffff8880353f6f98 R15: ffff88801ff8bd00
rt_spin_unlock+0x29/0x200 kernel/locking/spinlock_rt.c:80
spin_unlock_irqrestore include/linux/spinlock_rt.h:129 [inline]
__skb_try_recv_datagram+0xa9/0x1b0 net/core/datagram.c:267
__unix_dgram_recvmsg+0x2e3/0xd60 net/unix/af_unix.c:2573
sock_recvmsg_nosec+0x10c/0x140 net/socket.c:1078
____sys_recvmsg+0x3ef/0x4b0 net/socket.c:2810
___sys_recvmsg+0x215/0x590 net/socket.c:2854
do_recvmmsg+0x33a/0x800 net/socket.c:2949
__sys_recvmmsg net/socket.c:3023 [inline]
__do_sys_recvmmsg net/socket.c:3046 [inline]
__se_sys_recvmmsg net/socket.c:3039 [inline]
__x64_sys_recvmmsg+0x198/0x250 net/socket.c:3039
do_syscall_x64 arch/x86/entry/syscall_64.c:63 [inline]
do_syscall_64+0x14d/0xf80 arch/x86/entry/syscall_64.c:94
entry_SYSCALL_64_after_hwframe+0x77/0x7f
RIP: 0033:0x7f7f438dc819
RSP: 002b:00007f7f41b0d028 EFLAGS: 00000246 ORIG_RAX: 000000000000012b
RAX: ffffffffffffffda RBX: 00007f7f43b56090 RCX: 00007f7f438dc819
RDX: 0000000000010106 RSI: 00002000000000c0 RDI: 0000000000000005
RBP: 00007f7f43972c91 R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000002 R11: 0000000000000246 R12: 0000000000000000
R13: 00007f7f43b56128 R14: 00007f7f43b56090 R15: 00007ffce5780948
task:ktimers/1 state:R running task stack:23800 pid:29 tgid:29 ppid:2 task_flags:0x4208040 flags:0x00080000
Call Trace:
context_switch kernel/sched/core.c:5298 [inline]
__schedule+0x1553/0x5240 kernel/sched/core.c:6911
preempt_schedule_common+0x82/0xd0 kernel/sched/core.c:7095
preempt_schedule_thunk+0x16/0x30 arch/x86/entry/thunk.S:12
class_preempt_destructor include/linux/preempt.h:468 [inline]
try_to_wake_up+0x832/0x1380 kernel/sched/core.c:4249
hrtimer_wakeup+0x4e/0x60 kernel/time/hrtimer.c:2021
__run_hrtimer kernel/time/hrtimer.c:1785 [inline]
__hrtimer_run_queues+0x55f/0xda0 kernel/time/hrtimer.c:1849
hrtimer_run_softirq+0x192/0x5d0 kernel/time/hrtimer.c:1866
handle_softirqs+0x1de/0x6f0 kernel/softirq.c:622
__do_softirq kernel/softirq.c:656 [inline]
run_ktimerd+0x69/0x100 kernel/softirq.c:1138
smpboot_thread_fn+0x541/0xa50 kernel/smpboot.c:160
kthread+0x388/0x470 kernel/kthread.c:436
ret_from_fork+0x51e/0xb90 arch/x86/kernel/process.c:158
ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:245
rcu: rcu_preempt kthread timer wakeup didn't happen for 9187 jiffies! g13593 f0x0 RCU_GP_WAIT_FQS(5) ->state=0x402
rcu: Possible timer handling issue on cpu=1 timer-softirq=9634
rcu: rcu_preempt kthread starved for 9188 jiffies! g13593 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:27776 pid:18 tgid:18 ppid:2 task_flags:0x208040 flags:0x00080000
Call Trace:
context_switch kernel/sched/core.c:5298 [inline]
__schedule+0x1553/0x5240 kernel/sched/core.c:6911
__schedule_loop kernel/sched/core.c:6993 [inline]
schedule+0x164/0x360 kernel/sched/core.c:7008
schedule_timeout+0x158/0x2c0 kernel/time/sleep_timeout.c:99
rcu_gp_fqs_loop+0x312/0x11d0 kernel/rcu/tree.c:2095
rcu_gp_kthread+0x9e/0x2b0 kernel/rcu/tree.c:2297
kthread+0x388/0x470 kernel/kthread.c:436
ret_from_fork+0x51e/0xb90 arch/x86/kernel/process.c:158
ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:245
rcu: Stack dump where RCU GP kthread last ran:
Sending NMI from CPU 0 to CPUs 1:
NMI backtrace for cpu 1
CPU: 1 UID: 0 PID: 6425 Comm: syz.3.130 Not tainted syzkaller #0 PREEMPT_{RT,(full)}
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 02/12/2026
RIP: 0010:syscall_return_via_sysret+0x1a/0x87
Code: 1c 00 00 e8 50 3f 23 0a 84 c0 0f 84 58 15 00 00 66 90 b9 48 00 00 00 65 48 8b 15 e1 d3 4e 11 83 e2 fe 89 d0 48 c1 ea 20 0f 30 <41> 5f 41 5e 41 5d 41 5c 5d 5b 41 5b 41 5a 41 59 41 58 58 59 5a 5e
RSP: 0018:ffffc900063f7f48 EFLAGS: 00000046
RAX: 0000000000000000 RBX: 0000000000000000 RCX: 0000000000000048
RDX: 0000000000000000 RSI: ffffffff8d5648b1 RDI: ffffffff8ba67680
RBP: 0000000000000000 R08: ffffffff8f6a6ab7 R09: 1ffffffff1ed4d56
R10: dffffc0000000000 R11: fffffbfff1ed4d57 R12: 0000000000000000
R13: 0000000000000000 R14: 0000000000000000 R15: 0000000000000000
FS: 00007f62e3ff66c0(0000) GS:ffff888126436000(0000) knlGS:0000000000000000
CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 00007f2b035262fc CR3: 0000000051062000 CR4: 00000000003526f0
Call Trace:
RIP: 0033:0x7f62e5d9c819
Code: ff c3 66 2e 0f 1f 84 00 00 00 00 00 0f 1f 44 00 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 e8 ff ff ff f7 d8 64 89 01 48
RSP: 002b:00007f62e3ff60e8 EFLAGS: 00000246 ORIG_RAX: 00000000000000ca
RAX: ffffffffffffffda RBX: 00007f62e6015fa8 RCX: 00007f62e5d9c819
RDX: 0000000000000000 RSI: 0000000000000080 RDI: 00007f62e6015fa8
RBP: 00007f62e6015fa0 R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000
R13: 00007f62e6016038 R14: 00007fff2fd5a700 R15: 00007fff2fd5a7e8