rcu: INFO: rcu_preempt detected stalls on CPUs/tasks: rcu: 0-...!: (2 ticks this GP) idle=0a9c/1/0x4000000000000000 softirq=151673/151673 fqs=1 rcu: (detected by 1, t=10504 jiffies, g=196169, q=66 ncpus=2) Sending NMI from CPU 1 to CPUs 0: NMI backtrace for cpu 0 CPU: 0 PID: 7694 Comm: syz-executor.0 Not tainted 6.4.0-syzkaller-12365-g8689f4f2ea56 #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 07/03/2023 RIP: 0010:__lock_acquire+0x7d/0x5e20 kernel/locking/lockdep.c:5000 Code: 89 44 24 08 48 89 44 24 20 48 8d 84 24 a0 00 00 00 48 c1 e8 03 48 89 44 24 30 48 01 d0 c7 00 f1 f1 f1 f1 c7 40 04 f1 f1 04 f2 40 08 00 f3 f3 f3 65 48 8b 04 25 28 00 00 00 48 89 84 24 18 01 RSP: 0018:ffffc90000007ad0 EFLAGS: 00000082 RAX: fffff52000000f6e RBX: 1ffff92000000f8c RCX: 0000000000000000 RDX: dffffc0000000000 RSI: 0000000000000000 RDI: ffffffff92380250 RBP: 0000000000000000 R08: 0000000000000001 R09: 0000000000000001 R10: ffffffff8eaa7257 R11: 0000000000000001 R12: 0000000000000000 R13: ffffffff92380250 R14: 0000000000000000 R15: 0000000000000000 FS: 00007fe6ba802700(0000) GS:ffff8880b9800000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: 0000001b2eb42000 CR3: 00000000218ed000 CR4: 0000000000350ef0 Call Trace: lock_acquire kernel/locking/lockdep.c:5761 [inline] lock_acquire+0x1b1/0x520 kernel/locking/lockdep.c:5726 __raw_spin_lock_irqsave include/linux/spinlock_api_smp.h:110 [inline] _raw_spin_lock_irqsave+0x3d/0x60 kernel/locking/spinlock.c:162 debug_object_deactivate lib/debugobjects.c:783 [inline] debug_object_deactivate+0x105/0x300 lib/debugobjects.c:771 debug_hrtimer_deactivate kernel/time/hrtimer.c:427 [inline] debug_deactivate kernel/time/hrtimer.c:483 [inline] __run_hrtimer kernel/time/hrtimer.c:1656 [inline] __hrtimer_run_queues+0x3fd/0xc00 kernel/time/hrtimer.c:1752 hrtimer_interrupt+0x320/0x7b0 kernel/time/hrtimer.c:1814 local_apic_timer_interrupt arch/x86/kernel/apic/apic.c:1098 [inline] __sysvec_apic_timer_interrupt+0x14a/0x430 arch/x86/kernel/apic/apic.c:1115 sysvec_apic_timer_interrupt+0x92/0xc0 arch/x86/kernel/apic/apic.c:1109 asm_sysvec_apic_timer_interrupt+0x1a/0x20 arch/x86/include/asm/idtentry.h:645 RIP: 0010:should_fail_ex+0x5b/0x5b0 lib/fault-inject.c:108 Code: b9 03 00 49 8d bd ac 15 00 00 48 b8 00 00 00 00 00 fc ff df 48 89 fa 48 c1 ea 03 0f b6 14 02 48 89 f8 83 e0 07 83 c0 03 38 d0 <7c> 08 84 d2 0f 85 50 04 00 00 41 8b 85 ac 15 00 00 85 c0 74 5a 65 RSP: 0018:ffffc90003937a20 EFLAGS: 00000202 RAX: 0000000000000007 RBX: ffffffff8d38e6c0 RCX: ffffc90004213000 RDX: 0000000000000000 RSI: 0000000000000001 RDI: ffff8880842ad12c RBP: 0000000000000001 R08: 0000000000000001 R09: fffffbfff1d54e4a R10: ffffffff8eaa7257 R11: 0000000000000001 R12: 0000000000000000 R13: ffff8880842abb80 R14: ffffc90003937bb0 R15: ffffc90003937b90 _copy_from_user+0x30/0xf0 lib/usercopy.c:15 copy_from_user include/linux/uaccess.h:183 [inline] copy_msghdr_from_user+0x89/0x150 net/socket.c:2424 recvmsg_copy_msghdr net/socket.c:2679 [inline] ___sys_recvmsg+0xbc/0x180 net/socket.c:2751 do_recvmmsg+0x25e/0x6f0 net/socket.c:2849 __sys_recvmmsg net/socket.c:2928 [inline] __do_sys_recvmmsg net/socket.c:2951 [inline] __se_sys_recvmmsg net/socket.c:2944 [inline] __x64_sys_recvmmsg+0x20f/0x260 net/socket.c:2944 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: 0033:0x7fe6b9a8c389 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:00007fe6ba802168 EFLAGS: 00000246 ORIG_RAX: 000000000000012b RAX: ffffffffffffffda RBX: 00007fe6b9bac050 RCX: 00007fe6b9a8c389 RDX: 0000000000010106 RSI: 00000000200000c0 RDI: 0000000000000004 RBP: 00007fe6b9ad7493 R08: 0000000000000000 R09: 0000000000000000 R10: 0000000000000002 R11: 0000000000000246 R12: 0000000000000000 R13: 00007fff0594373f R14: 00007fe6ba802300 R15: 0000000000022000 rcu: rcu_preempt kthread starved for 10502 jiffies! g196169 f0x0 RCU_GP_WAIT_FQS(5) ->state=0x0 ->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:R running task stack:27872 pid:16 ppid:2 flags:0x00004000 Call Trace: context_switch kernel/sched/core.c:5381 [inline] __schedule+0xc9a/0x5880 kernel/sched/core.c:6710 schedule+0xde/0x1a0 kernel/sched/core.c:6786 schedule_timeout+0x14e/0x2b0 kernel/time/timer.c:2167 rcu_gp_fqs_loop+0x190/0x910 kernel/rcu/tree.c:1609 rcu_gp_kthread+0x23a/0x360 kernel/rcu/tree.c:1808 kthread+0x344/0x440 kernel/kthread.c:389 ret_from_fork+0x1f/0x30 arch/x86/entry/entry_64.S:308 rcu: Stack dump where RCU GP kthread last ran: CPU: 1 PID: 7701 Comm: syz-executor.2 Not tainted 6.4.0-syzkaller-12365-g8689f4f2ea56 #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 07/03/2023 RIP: 0010:csd_lock_wait kernel/smp.c:296 [inline] RIP: 0010:smp_call_function_many_cond+0x694/0x1720 kernel/smp.c:835 Code: 89 ee e8 2f 50 0b 00 85 ed 74 48 48 8b 44 24 08 49 89 c4 83 e0 07 49 c1 ec 03 48 89 c5 4d 01 f4 83 c5 03 e8 ee 53 0b 00 f3 90 <41> 0f b6 04 24 40 38 c5 7c 08 84 c0 0f 85 d1 0d 00 00 8b 43 08 31 RSP: 0018:ffffc9000340fb88 EFLAGS: 00000246 RAX: 0000000000040000 RBX: ffff8880b9844fe0 RCX: ffffc9000b8d2000 RDX: 0000000000040000 RSI: ffffffff81798b82 RDI: 0000000000000005 RBP: 0000000000000003 R08: 0000000000000005 R09: 0000000000000000 R10: 0000000000000001 R11: 0000000000000001 R12: ffffed10173089fd R13: 0000000000000000 R14: dffffc0000000000 R15: 0000000000000001 FS: 00007feaf1d5b700(0000) GS:ffff8880b9900000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: 0000000020001680 CR3: 0000000036f52000 CR4: 0000000000350ee0 Call Trace: clock_was_set+0x17b/0x830 kernel/time/hrtimer.c:976 do_settimeofday64 kernel/time/timekeeping.c:1345 [inline] do_settimeofday64+0x3c4/0x5d0 kernel/time/timekeeping.c:1312 do_sys_settimeofday64 kernel/time/time.c:195 [inline] do_sys_settimeofday64+0x1e2/0x270 kernel/time/time.c:169 __do_sys_clock_settime kernel/time/posix-timers.c:1129 [inline] __se_sys_clock_settime kernel/time/posix-timers.c:1113 [inline] __x64_sys_clock_settime+0x1a5/0x280 kernel/time/posix-timers.c:1113 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: 0033:0x7feaf108c389 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:00007feaf1d5b168 EFLAGS: 00000246 ORIG_RAX: 00000000000000e3 RAX: ffffffffffffffda RBX: 00007feaf11abf80 RCX: 00007feaf108c389 RDX: 0000000000000000 RSI: 0000000020000440 RDI: 0000000000000000 RBP: 00007feaf10d7493 R08: 0000000000000000 R09: 0000000000000000 R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000 R13: 00007fff9b41c39f R14: 00007feaf1d5b300 R15: 0000000000022000