rcu: INFO: rcu_preempt detected stalls on CPUs/tasks: (detected by 1, t=10502 jiffies, g=17233, q=4) rcu: All QSes seen, last rcu_preempt kthread activity 10502 (4294974093-4294963591), jiffies_till_next_fqs=1, root ->qsmask 0x0 rcu: rcu_preempt kthread starved for 10502 jiffies! g17233 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:27064 pid: 15 ppid: 2 flags:0x00004000 Call Trace: context_switch kernel/sched/core.c:5027 [inline] __schedule+0x12c4/0x45b0 kernel/sched/core.c:6373 schedule+0x11b/0x1f0 kernel/sched/core.c:6456 schedule_timeout+0x1b9/0x300 kernel/time/timer.c:1914 rcu_gp_fqs_loop+0x2bf/0x1080 kernel/rcu/tree.c:1972 rcu_gp_kthread+0xa4/0x360 kernel/rcu/tree.c:2145 kthread+0x3f6/0x4f0 kernel/kthread.c:334 ret_from_fork+0x1f/0x30 arch/x86/entry/entry_64.S:287 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: 5985 Comm: syz.0.648 Not tainted 5.15.168-syzkaller #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 09/13/2024 RIP: 0010:debug_smp_processor_id+0xe/0x10 lib/smp_processor_id.c:60 Code: 00 00 00 00 48 c7 c7 80 fc 92 8a e8 2c 01 00 00 65 ff 0d b1 f1 ce 75 5b c3 cc cc cc 48 c7 c7 20 02 d9 8a 48 c7 c6 60 02 d9 8a 00 41 57 41 56 41 54 53 48 83 ec 10 65 48 8b 04 25 28 00 00 00 RSP: 0018:ffffc90000007cf8 EFLAGS: 00000086 RAX: 0000000000010000 RBX: 0000000000000001 RCX: ffff8880283fd940 RDX: ffff8880283fd940 RSI: ffffffff8ad90260 RDI: ffffffff8ad90220 RBP: ffff88801f2f9d28 R08: ffffffff814fee8c R09: fffffbfff20ec621 R10: 0000000000000000 R11: dffffc0000000001 R12: ffff8880283fd940 R13: dffffc0000000000 R14: 0000000000000a20 R15: ffffffff8c7dab00 FS: 0000555574753500(0000) GS:ffff8880b9000000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: 00007f0d3e67a000 CR3: 0000000029c4f000 CR4: 00000000003506f0 DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000 DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400 Call Trace: rcu_dynticks_curr_cpu_in_eqs kernel/rcu/tree.c:331 [inline] rcu_is_watching+0x11/0xa0 kernel/rcu/tree.c:1123 rcu_read_unlock include/linux/rcupdate.h:768 [inline] __sigqueue_alloc+0x1d5/0x4d0 kernel/signal.c:428 __send_signal+0x21f/0xd40 kernel/signal.c:1116 do_send_sig_info kernel/signal.c:1294 [inline] group_send_sig_info+0x260/0x2d0 kernel/signal.c:1442 do_bpf_send_signal+0x81/0x150 kernel/trace/bpf_trace.c:779 irq_work_single kernel/irq_work.c:155 [inline] irq_work_run_list+0x20b/0x370 kernel/irq_work.c:177 irq_work_run+0x63/0xe0 kernel/irq_work.c:186 __sysvec_irq_work+0x9a/0x250 arch/x86/kernel/irq_work.c:22 instr_sysvec_irq_work arch/x86/kernel/irq_work.c:17 [inline] sysvec_irq_work+0x98/0xc0 arch/x86/kernel/irq_work.c:17 asm_sysvec_irq_work+0x16/0x20 arch/x86/include/asm/idtentry.h:713 RIP: 0010:__raw_spin_unlock_irq include/linux/spinlock_api_smp.h:169 [inline] RIP: 0010:_raw_spin_unlock_irq+0x25/0x40 kernel/locking/spinlock.c:202 Code: 51 67 f6 ff 90 53 48 89 fb 48 83 c7 18 48 8b 74 24 08 e8 6e fb 24 f7 48 89 df e8 c6 4f 26 f7 e8 01 0a 49 f7 fb bf 01 00 00 00 26 95 19 f7 65 8b 05 37 88 c4 75 85 c0 74 02 5b c3 e8 04 a5 c2 RSP: 0018:ffffc900030e7bc0 EFLAGS: 00000282 RAX: afa4024d57c0b800 RBX: ffff888077f16f00 RCX: ffffffff96869f03 RDX: dffffc0000000000 RSI: ffffffff8a8b2a80 RDI: 0000000000000001 RBP: 0000000000000000 R08: ffffffff8186f1b0 R09: ffffed100efe2de1 R10: 0000000000000000 R11: dffffc0000000001 R12: 0000000000000021 R13: dffffc0000000000 R14: ffff888077f17398 R15: ffff888077f16f00 spin_unlock_irq include/linux/spinlock.h:413 [inline] get_signal+0x13ee/0x14e0 kernel/signal.c:2903 arch_do_signal_or_restart+0xc3/0x1890 arch/x86/kernel/signal.c:867 handle_signal_work kernel/entry/common.c:154 [inline] exit_to_user_mode_loop+0x97/0x130 kernel/entry/common.c:178 exit_to_user_mode_prepare+0xb1/0x140 kernel/entry/common.c:214 __syscall_exit_to_user_mode_work kernel/entry/common.c:296 [inline] syscall_exit_to_user_mode+0x5d/0x240 kernel/entry/common.c:307 do_syscall_64+0x47/0xb0 arch/x86/entry/common.c:86 entry_SYSCALL_64_after_hwframe+0x66/0xd0 RIP: 0033:0x7f0d403273c0 Code: 10 83 e0 01 83 e2 01 88 15 2a 53 e2 00 88 05 27 53 e2 00 c3 50 48 8d 35 de fe 1a 00 48 8d 3d e4 fe 1a 00 31 c0 e8 a0 f9 ff ff <53> 89 fb 48 83 ec 10 64 8b 04 25 94 ff ff ff 85 c0 74 2a 89 fe 31 RSP: 002b:00007ffd04d12b38 EFLAGS: 00000246 RAX: 0000000000000000 RBX: 00007f0d4061d2a0 RCX: 00007f0d4041c307 RDX: 00007ffd04d12b40 RSI: 00007ffd04d12c70 RDI: 0000000000000007 RBP: 00007f0d4061d214 R08: 00007f0d4061cf80 R09: 00007ffd04d12f87 R10: 0000000000000008 R11: 0000000000000246 R12: 0000000000000003 R13: 00007f0d4061d208 R14: 0000000000000005 R15: 0000000000001255