rcu: INFO: rcu_preempt detected stalls on CPUs/tasks: rcu: Tasks blocked on level-0 rcu_node (CPUs 0-1): P25472/1:b..l P31481/1:b..l rcu: (detected by 0, t=10506 jiffies, g=138349, q=157 ncpus=2) task:syz.4.6766 state:R running task stack:26336 pid:31481 tgid:31480 ppid:26302 flags:0x00004002 Call Trace: context_switch kernel/sched/core.c:5369 [inline] __schedule+0xe58/0x5ad0 kernel/sched/core.c:6756 preempt_schedule_common+0x44/0xc0 kernel/sched/core.c:6935 preempt_schedule_thunk+0x1a/0x30 arch/x86/entry/thunk.S:12 class_preempt_destructor include/linux/preempt.h:480 [inline] class_preempt_destructor include/linux/preempt.h:480 [inline] migrate_enable+0x203/0x260 kernel/sched/core.c:2403 bpf_test_timer_leave+0xc8/0x170 net/bpf/test_run.c:57 bpf_test_timer_continue+0x32e/0x3d0 net/bpf/test_run.c:84 bpf_test_run+0x3c6/0xa90 net/bpf/test_run.c:438 bpf_prog_test_run_xdp+0xcca/0x1580 net/bpf/test_run.c:1320 bpf_prog_test_run kernel/bpf/syscall.c:4402 [inline] __sys_bpf+0xfc6/0x49c0 kernel/bpf/syscall.c:5808 __do_sys_bpf kernel/bpf/syscall.c:5897 [inline] __se_sys_bpf kernel/bpf/syscall.c:5895 [inline] __x64_sys_bpf+0x78/0xc0 kernel/bpf/syscall.c:5895 do_syscall_x64 arch/x86/entry/common.c:52 [inline] do_syscall_64+0xcd/0x250 arch/x86/entry/common.c:83 entry_SYSCALL_64_after_hwframe+0x77/0x7f RIP: 0033:0x7f89a8185d29 RSP: 002b:00007f89a8fb9038 EFLAGS: 00000246 ORIG_RAX: 0000000000000141 RAX: ffffffffffffffda RBX: 00007f89a8375fa0 RCX: 00007f89a8185d29 RDX: 0000000000000050 RSI: 00000000200011c0 RDI: 000000000000000a RBP: 00007f89a8201b08 R08: 0000000000000000 R09: 0000000000000000 R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000 R13: 0000000000000000 R14: 00007f89a8375fa0 R15: 00007ffdec56afc8 task:syz.0.5253 state:R running task stack:26064 pid:25472 tgid:25471 ppid:21121 flags:0x00004006 Call Trace: context_switch kernel/sched/core.c:5369 [inline] __schedule+0xe58/0x5ad0 kernel/sched/core.c:6756 preempt_schedule_irq+0x51/0x90 kernel/sched/core.c:7078 irqentry_exit+0x36/0x90 kernel/entry/common.c:354 asm_sysvec_apic_timer_interrupt+0x1a/0x20 arch/x86/include/asm/idtentry.h:702 RIP: 0010:lockdep_enabled kernel/locking/lockdep.c:122 [inline] RIP: 0010:lock_is_held_type+0x45/0x150 kernel/locking/lockdep.c:5914 Code: b1 35 05 85 c9 0f 84 dd 00 00 00 65 8b 05 0b d3 d8 74 85 c0 0f 85 ce 00 00 00 65 4c 8b 25 33 20 da 74 41 8b 94 24 dc 0a 00 00 <85> d2 0f 85 b6 00 00 00 48 89 fd 41 89 f6 9c 8f 04 24 fa 48 c7 c7 RSP: 0018:ffffc9000be4f9f8 EFLAGS: 00000246 RAX: 0000000000000000 RBX: 0000000000000001 RCX: 0000000000000001 RDX: 0000000000000000 RSI: 00000000ffffffff RDI: ffffffff8e1bb900 RBP: 1ffff920017c9f47 R08: 0000000000000005 R09: 0000000000000000 R10: 0000000000000001 R11: 0000000000000001 R12: ffff8880a6452440 R13: 00000000ffffffff R14: 0000000000000000 R15: 0000000000000000 io_eventfd_grab+0x3a5/0x5e0 io_uring/eventfd.c:103 io_eventfd_flush_signal+0x1a/0x1b0 io_uring/eventfd.c:130 __io_commit_cqring_flush+0x163/0x5b0 io_uring/io_uring.c:579 io_commit_cqring_flush io_uring/io_uring.h:384 [inline] io_cq_unlock_post+0x149/0x190 io_uring/io_uring.c:613 __io_cqring_overflow_flush+0x480/0x680 io_uring/io_uring.c:665 io_cqring_do_overflow_flush io_uring/io_uring.c:677 [inline] io_cqring_wait+0x1422/0x1800 io_uring/io_uring.c:2616 __do_sys_io_uring_enter+0xf14/0x1620 io_uring/io_uring.c:3439 do_syscall_x64 arch/x86/entry/common.c:52 [inline] do_syscall_64+0xcd/0x250 arch/x86/entry/common.c:83 entry_SYSCALL_64_after_hwframe+0x77/0x7f RIP: 0033:0x7f7419385d29 RSP: 002b:00007f741a1d4038 EFLAGS: 00000246 ORIG_RAX: 00000000000001aa RAX: ffffffffffffffda RBX: 00007f7419575fa0 RCX: 00007f7419385d29 RDX: 0000000000000003 RSI: 0000000000000001 RDI: 0000000000000003 RBP: 00007f7419401b08 R08: 0000000000000000 R09: 0000000000000000 R10: 0000000000000001 R11: 0000000000000246 R12: 0000000000000000 R13: 0000000000000000 R14: 00007f7419575fa0 R15: 00007ffe48491288 rcu: rcu_preempt kthread starved for 10475 jiffies! g138349 f0x0 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:26336 pid:17 tgid:17 ppid:2 flags:0x00004000 Call Trace: context_switch kernel/sched/core.c:5369 [inline] __schedule+0xe58/0x5ad0 kernel/sched/core.c:6756 __schedule_loop kernel/sched/core.c:6833 [inline] schedule+0xe7/0x350 kernel/sched/core.c:6848 schedule_timeout+0x124/0x280 kernel/time/sleep_timeout.c:99 rcu_gp_fqs_loop+0x1eb/0xb00 kernel/rcu/tree.c:2045 rcu_gp_kthread+0x271/0x380 kernel/rcu/tree.c:2247 kthread+0x2c1/0x3a0 kernel/kthread.c:389 ret_from_fork+0x45/0x80 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: CPU: 0 UID: 0 PID: 31488 Comm: syz.2.6767 Not tainted 6.13.0-rc5-syzkaller-00012-g0bc21e701a6f #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 09/13/2024 RIP: 0010:csd_lock_wait kernel/smp.c:340 [inline] RIP: 0010:smp_call_function_many_cond+0x458/0x1300 kernel/smp.c:884 Code: 0c 00 85 ed 74 4d 48 b8 00 00 00 00 00 fc ff df 4d 89 f4 4c 89 f5 49 c1 ec 03 83 e5 07 49 01 c4 83 c5 03 e8 ba 0e 0c 00 f3 90 <41> 0f b6 04 24 40 38 c5 7c 08 84 c0 0f 85 a7 0c 00 00 8b 43 08 31 RSP: 0018:ffffc90012287b88 EFLAGS: 00000246 RAX: 0000000000080000 RBX: ffff8880b8744a40 RCX: ffffc900171a3000 RDX: 0000000000080000 RSI: ffffffff818e0766 RDI: 0000000000000005 RBP: 0000000000000003 R08: 0000000000000005 R09: 0000000000000000 R10: 0000000000000001 R11: 0000000000000003 R12: ffffed10170e8949 R13: 0000000000000001 R14: ffff8880b8744a48 R15: ffff8880b863fe40 FS: 00007fa365bd36c0(0000) GS:ffff8880b8600000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: 000000110c3b7a1a CR3: 0000000035188000 CR4: 00000000003526f0 DR0: 0000000000000000 DR1: 00000000872c9164 DR2: 0000000000000000 DR3: 0000000000000000 DR6: 00000000ffff0ff0 DR7: 0000000000000400 Call Trace: on_each_cpu_cond_mask+0x40/0x90 kernel/smp.c:1051 __flush_tlb_multi arch/x86/include/asm/paravirt.h:91 [inline] flush_tlb_multi arch/x86/mm/tlb.c:939 [inline] flush_tlb_mm_range+0x289/0x330 arch/x86/mm/tlb.c:1025 tlb_flush arch/x86/include/asm/tlb.h:20 [inline] tlb_flush_mmu_tlbonly include/asm-generic/tlb.h:465 [inline] tlb_flush_mmu_tlbonly include/asm-generic/tlb.h:455 [inline] tlb_flush_mmu mm/mmu_gather.c:372 [inline] tlb_finish_mmu+0x3c9/0x7b0 mm/mmu_gather.c:465 do_mprotect_pkey+0xa9c/0xcf0 mm/mprotect.c:848 __do_sys_mprotect mm/mprotect.c:861 [inline] __se_sys_mprotect mm/mprotect.c:858 [inline] __x64_sys_mprotect+0x78/0xc0 mm/mprotect.c:858 do_syscall_x64 arch/x86/entry/common.c:52 [inline] do_syscall_64+0xcd/0x250 arch/x86/entry/common.c:83 entry_SYSCALL_64_after_hwframe+0x77/0x7f RIP: 0033:0x7fa368185d29 Code: ff ff c3 66 2e 0f 1f 84 00 00 00 00 00 0f 1f 40 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 a8 ff ff ff f7 d8 64 89 01 48 RSP: 002b:00007fa365bd3038 EFLAGS: 00000246 ORIG_RAX: 000000000000000a RAX: ffffffffffffffda RBX: 00007fa368376240 RCX: 00007fa368185d29 RDX: 000000000000000c RSI: 0000000000002000 RDI: 0000000020000000 RBP: 00007fa368201b08 R08: 0000000000000000 R09: 0000000000000000 R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000 R13: 0000000000000000 R14: 00007fa368376240 R15: 00007ffef6e74258