rcu: INFO: rcu_preempt detected stalls on CPUs/tasks: rcu: (detected by 1, t=10504 jiffies, g=347725, q=383 ncpus=2) rcu: All QSes seen, last rcu_preempt kthread activity 10504 (4295213720-4295203216), jiffies_till_next_fqs=1, root ->qsmask 0x0 rcu: rcu_preempt kthread starved for 10504 jiffies! g347725 f0x2 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:26256 pid:16 tgid:16 ppid:2 flags:0x00004000 Call Trace: context_switch kernel/sched/core.c:5409 [inline] __schedule+0x1796/0x4a00 kernel/sched/core.c:6746 __schedule_loop kernel/sched/core.c:6823 [inline] schedule+0x14b/0x320 kernel/sched/core.c:6838 schedule_timeout+0x1be/0x310 kernel/time/timer.c:2582 rcu_gp_fqs_loop+0x2df/0x1370 kernel/rcu/tree.c:1663 rcu_gp_kthread+0xa7/0x3b0 kernel/rcu/tree.c:1862 kthread+0x2f0/0x390 kernel/kthread.c:388 ret_from_fork+0x4b/0x80 arch/x86/kernel/process.c:147 ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:244 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: 12354 Comm: syz-executor.0 Not tainted 6.9.0-rc7-syzkaller-00056-g45db3ab70092 #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 04/02/2024 RIP: 0010:hlock_class kernel/locking/lockdep.c:228 [inline] RIP: 0010:check_wait_context kernel/locking/lockdep.c:4774 [inline] RIP: 0010:__lock_acquire+0x5d2/0x1fd0 kernel/locking/lockdep.c:5087 Code: 41 8b 1f 81 e3 ff 1f 00 00 48 89 d8 48 c1 e8 06 48 8d 3c c5 00 e5 ef 92 be 08 00 00 00 e8 e6 d5 84 00 48 0f a3 1d fe 54 7d 11 <73> 22 48 69 c3 c8 00 00 00 48 8d 98 00 44 be 92 48 ba 00 00 00 00 RSP: 0018:ffffc90000007a30 EFLAGS: 00000057 RAX: 0000000000000001 RBX: 000000000000104d RCX: ffffffff81728ffa RDX: 0000000000000000 RSI: 0000000000000008 RDI: ffffffff92efe708 RBP: 0000000000000002 R08: ffffffff92efe70f R09: 1ffffffff25dfce1 R10: dffffc0000000000 R11: fffffbfff25dfce2 R12: 0000000000000001 R13: ffff888027128000 R14: 0000000000000000 R15: ffff888027128af8 FS: 00007fe37925e6c0(0000) GS:ffff8880b9400000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: 0000001b31629000 CR3: 0000000060cd8000 CR4: 00000000003506f0 DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000 DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400 Call Trace: lock_acquire+0x1ed/0x550 kernel/locking/lockdep.c:5754 __raw_spin_lock include/linux/spinlock_api_smp.h:133 [inline] _raw_spin_lock+0x2e/0x40 kernel/locking/spinlock.c:154 spin_lock include/linux/spinlock.h:351 [inline] advance_sched+0xab/0xca0 net/sched/sch_taprio.c:924 __run_hrtimer kernel/time/hrtimer.c:1692 [inline] __hrtimer_run_queues+0x5a5/0xd50 kernel/time/hrtimer.c:1756 hrtimer_interrupt+0x396/0x990 kernel/time/hrtimer.c:1818 local_apic_timer_interrupt arch/x86/kernel/apic/apic.c:1032 [inline] __sysvec_apic_timer_interrupt+0x110/0x3f0 arch/x86/kernel/apic/apic.c:1049 instr_sysvec_apic_timer_interrupt arch/x86/kernel/apic/apic.c:1043 [inline] sysvec_apic_timer_interrupt+0xa1/0xc0 arch/x86/kernel/apic/apic.c:1043 asm_sysvec_apic_timer_interrupt+0x1a/0x20 arch/x86/include/asm/idtentry.h:702 RIP: 0010:lock_is_held_type+0x13b/0x190 Code: 75 44 48 c7 04 24 00 00 00 00 9c 8f 04 24 f7 04 24 00 02 00 00 75 4c 41 f7 c4 00 02 00 00 74 01 fb 65 48 8b 04 25 28 00 00 00 <48> 3b 44 24 08 75 42 89 d8 48 83 c4 10 5b 41 5c 41 5d 41 5e 41 5f RSP: 0018:ffffc9000661f798 EFLAGS: 00000206 RAX: 68f25ceb1c1dc800 RBX: 0000000000000000 RCX: ffff888027128000 RDX: 0000000000000000 RSI: ffffffff8bcaca20 RDI: ffffffff8c1eae20 RBP: ffffc9000661f8f8 R08: ffffffff81e0f651 R09: 0000000000000000 R10: ffffc9000661f9c0 R11: fffff52000cc3f3f R12: 0000000000000246 R13: ffff888027128000 R14: 00000000ffffffff R15: ffffffff8e334d20 lock_is_held include/linux/lockdep.h:231 [inline] __might_resched+0xf4/0x780 kernel/sched/core.c:10159 __might_fault+0x72/0x120 mm/memory.c:6217 _copy_from_user+0x2a/0xe0 lib/usercopy.c:14 copy_from_user include/linux/uaccess.h:183 [inline] copy_msghdr_from_user+0xae/0x680 net/socket.c:2514 recvmsg_copy_msghdr net/socket.c:2769 [inline] ___sys_recvmsg net/socket.c:2841 [inline] do_recvmmsg+0x40f/0xae0 net/socket.c:2939 __sys_recvmmsg net/socket.c:3018 [inline] __do_sys_recvmmsg net/socket.c:3041 [inline] __se_sys_recvmmsg net/socket.c:3034 [inline] __x64_sys_recvmmsg+0x199/0x250 net/socket.c:3034 do_syscall_x64 arch/x86/entry/common.c:52 [inline] do_syscall_64+0xf5/0x240 arch/x86/entry/common.c:83 entry_SYSCALL_64_after_hwframe+0x77/0x7f RIP: 0033:0x7fe37847dd69 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:00007fe37925e0c8 EFLAGS: 00000246 ORIG_RAX: 000000000000012b RAX: ffffffffffffffda RBX: 00007fe3785ac050 RCX: 00007fe37847dd69 RDX: 0000000000010106 RSI: 00000000200000c0 RDI: 0000000000000005 RBP: 00007fe3784ca49e R08: 0000000000000000 R09: 0000000000000000 R10: 0000000000000002 R11: 0000000000000246 R12: 0000000000000000 R13: 000000000000006e R14: 00007fe3785ac050 R15: 00007ffc259fe0d8