rcu: INFO: rcu_preempt detected stalls on CPUs/tasks: rcu: Tasks blocked on level-0 rcu_node (CPUs 0-1): P6386/1:b..l P6390/1:b..l rcu: (detected by 1, t=10503 jiffies, g=18065, q=343 ncpus=2) task:syz-executor.2 state:R running task stack:26416 pid:6390 tgid:6388 ppid:5099 flags:0x00000002 Call Trace: context_switch kernel/sched/core.c:5409 [inline] __schedule+0x1796/0x4a00 kernel/sched/core.c:6746 preempt_schedule_irq+0xfb/0x1c0 kernel/sched/core.c:7068 irqentry_exit+0x5e/0x90 kernel/entry/common.c:354 asm_sysvec_apic_timer_interrupt+0x1a/0x20 arch/x86/include/asm/idtentry.h:702 RIP: 0010:lock_acquire+0x264/0x550 kernel/locking/lockdep.c:5758 Code: 2b 00 74 08 4c 89 f7 e8 ea 7b 85 00 f6 44 24 61 02 0f 85 85 01 00 00 41 f7 c7 00 02 00 00 74 01 fb 48 c7 44 24 40 0e 36 e0 45 <4b> c7 44 25 00 00 00 00 00 43 c7 44 25 09 00 00 00 00 43 c7 44 25 RSP: 0018:ffffc900035dfd60 EFLAGS: 00000206 RAX: 0000000000000001 RBX: 1ffff920006bbfb8 RCX: 0000000000000001 RDX: dffffc0000000000 RSI: ffffffff8bcac740 RDI: ffffffff8c1ed7e0 RBP: ffffc900035dfeb8 R08: ffffffff92f66587 R09: 1ffffffff25eccb0 R10: dffffc0000000000 R11: fffffbfff25eccb1 R12: 1ffff920006bbfb4 R13: dffffc0000000000 R14: ffffc900035dfdc0 R15: 0000000000000246 rcu_lock_acquire include/linux/rcupdate.h:329 [inline] rcu_read_lock include/linux/rcupdate.h:781 [inline] __task_pid_nr_ns+0x45/0x450 kernel/pid.c:510 task_tgid_vnr include/linux/pid.h:294 [inline] __do_sys_getpid+0x1e/0x30 kernel/sys.c:960 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: 0033:0x7f0df1c7a667 RSP: 002b:00007f0df2a0eb08 EFLAGS: 00000202 ORIG_RAX: 0000000000000027 RAX: ffffffffffffffda RBX: 00007f0df2a0ec70 RCX: 00007f0df1c7a667 RDX: 00007f0df2a0eb40 RSI: 00007f0df2a0ec70 RDI: 0000000000000021 RBP: 0000000000000000 R08: 0000000000000000 R09: 0000000000000000 R10: 0000000000000000 R11: 0000000000000202 R12: 0000000000000000 R13: 000000000000006e R14: 00007f0df1dac050 R15: 00007ffe1553c6e8 task:syz-executor.4 state:R running task stack:24848 pid:6386 tgid:6379 ppid:5114 flags:0x00004002 Call Trace: context_switch kernel/sched/core.c:5409 [inline] __schedule+0x1796/0x4a00 kernel/sched/core.c:6746 preempt_schedule_irq+0xfb/0x1c0 kernel/sched/core.c:7068 irqentry_exit+0x5e/0x90 kernel/entry/common.c:354 asm_sysvec_reschedule_ipi+0x1a/0x20 arch/x86/include/asm/idtentry.h:707 RIP: 0010:lock_acquire+0x264/0x550 kernel/locking/lockdep.c:5758 Code: 2b 00 74 08 4c 89 f7 e8 ea 7b 85 00 f6 44 24 61 02 0f 85 85 01 00 00 41 f7 c7 00 02 00 00 74 01 fb 48 c7 44 24 40 0e 36 e0 45 <4b> c7 44 25 00 00 00 00 00 43 c7 44 25 09 00 00 00 00 43 c7 44 25 RSP: 0018:ffffc900035cf000 EFLAGS: 00000206 RAX: 0000000000000001 RBX: 1ffff920006b9e0c RCX: 0000000000000001 RDX: dffffc0000000000 RSI: ffffffff8bcac740 RDI: ffffffff8c1ed7e0 RBP: ffffc900035cf148 R08: ffffffff92f66587 R09: 1ffffffff25eccb0 R10: dffffc0000000000 R11: fffffbfff25eccb1 R12: 1ffff920006b9e08 R13: dffffc0000000000 R14: ffffc900035cf060 R15: 0000000000000246 rcu_lock_acquire include/linux/rcupdate.h:329 [inline] rcu_read_lock include/linux/rcupdate.h:781 [inline] is_bpf_text_address+0x46/0x2a0 kernel/bpf/core.c:768 kernel_text_address+0xa7/0xe0 kernel/extable.c:125 __kernel_text_address+0xd/0x40 kernel/extable.c:79 unwind_get_return_address+0x5d/0xc0 arch/x86/kernel/unwind_orc.c:369 arch_stack_walk+0x125/0x1b0 arch/x86/kernel/stacktrace.c:26 stack_trace_save+0x118/0x1d0 kernel/stacktrace.c:122 kasan_save_stack mm/kasan/common.c:47 [inline] kasan_save_track+0x3f/0x80 mm/kasan/common.c:68 unpoison_slab_object mm/kasan/common.c:312 [inline] __kasan_slab_alloc+0x66/0x80 mm/kasan/common.c:338 kasan_slab_alloc include/linux/kasan.h:201 [inline] slab_post_alloc_hook mm/slub.c:3871 [inline] slab_alloc_node mm/slub.c:3918 [inline] kmem_cache_alloc_node+0x194/0x390 mm/slub.c:3961 kmalloc_reserve+0xa8/0x2a0 net/core/skbuff.c:575 __alloc_skb+0x1f3/0x440 net/core/skbuff.c:666 alloc_skb_fclone include/linux/skbuff.h:1358 [inline] tcp_stream_alloc_skb+0x3d/0x310 net/ipv4/tcp.c:879 tso_fragment net/ipv4/tcp_output.c:2167 [inline] tcp_write_xmit+0xfb1/0x69d0 net/ipv4/tcp_output.c:2815 __tcp_push_pending_frames+0x9b/0x360 net/ipv4/tcp_output.c:3014 tcp_push_pending_frames include/net/tcp.h:2102 [inline] tcp_data_snd_check net/ipv4/tcp_input.c:5660 [inline] tcp_rcv_established+0x1023/0x2020 net/ipv4/tcp_input.c:6179 tcp_v4_do_rcv+0x965/0xc60 net/ipv4/tcp_ipv4.c:1914 sk_backlog_rcv include/net/sock.h:1106 [inline] __release_sock+0x214/0x350 net/core/sock.c:2983 release_sock+0x61/0x1f0 net/core/sock.c:3549 tcp_sendmsg+0x3a/0x50 net/ipv4/tcp.c:1349 sock_sendmsg_nosec net/socket.c:730 [inline] __sock_sendmsg+0x1a6/0x270 net/socket.c:745 __sys_sendto+0x3a4/0x4f0 net/socket.c:2191 __do_sys_sendto net/socket.c:2203 [inline] __se_sys_sendto net/socket.c:2199 [inline] __x64_sys_sendto+0xde/0x100 net/socket.c:2199 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: 0033:0x7f4fd487cee9 RSP: 002b:00007f4fd564f0c8 EFLAGS: 00000246 ORIG_RAX: 000000000000002c RAX: ffffffffffffffda RBX: 00007f4fd49ac050 RCX: 00007f4fd487cee9 RDX: 000000000000fe6a RSI: 0000000020000700 RDI: 0000000000000005 RBP: 00007f4fd48c949e R08: 0000000000000000 R09: fffffffffffffe93 R10: 0000000000040040 R11: 0000000000000246 R12: 0000000000000000 R13: 000000000000006e R14: 00007f4fd49ac050 R15: 00007ffd0f484cf8 rcu: rcu_preempt kthread starved for 10336 jiffies! g18065 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:26800 pid:17 tgid:17 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:2000 rcu_gp_kthread+0xa7/0x3b0 kernel/rcu/tree.c:2202 kthread+0x2f0/0x390 kernel/kthread.c:389 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: 0 Comm: swapper/0 Not tainted 6.9.0-syzkaller-08284-gea5f6ad9ad96 #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 04/02/2024 RIP: 0010:ct_kernel_exit_state+0x0/0x50 kernel/context_tracking.c:82 Code: f9 e9 fe fe ff ff 48 c7 c7 80 23 3e 8e 48 89 de e8 65 b4 61 f9 e9 5a ff ff ff 90 90 90 90 90 90 90 90 90 90 90 90 90 90 90 90 <41> 56 53 89 fb e8 e6 09 00 00 41 89 c6 83 f8 08 73 27 4a 8b 04 f5 RSP: 0018:ffffffff8e007bd0 EFLAGS: 00000056 RAX: 0000000001927101 RBX: ffff8880b9400000 RCX: ffffffff8b7f2f12 RDX: 0000000000000001 RSI: 0000000000000004 RDI: 0000000000000004 RBP: 0000000000000000 R08: ffff8880b9437d0b R09: 1ffff11017286fa1 R10: dffffc0000000000 R11: ffffed1017286fa2 R12: 0000000000000000 R13: 0000000000000000 R14: ffff8880b9437d08 R15: 0000000000000000 FS: 0000000000000000(0000) GS:ffff8880b9400000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: 000055d6919b6048 CR3: 0000000023196000 CR4: 00000000003506f0 DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000 DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400 Call Trace: ct_nmi_exit+0xed/0x1c0 kernel/context_tracking.c:239 irqentry_exit+0x7f/0x90 kernel/entry/common.c:347 asm_sysvec_apic_timer_interrupt+0x1a/0x20 arch/x86/include/asm/idtentry.h:702 RIP: 0010:native_irq_disable arch/x86/include/asm/irqflags.h:37 [inline] RIP: 0010:arch_local_irq_disable arch/x86/include/asm/irqflags.h:72 [inline] RIP: 0010:acpi_safe_halt+0x21/0x30 drivers/acpi/processor_idle.c:113 Code: 90 90 90 90 90 90 90 90 90 65 48 8b 04 25 40 d3 03 00 48 f7 00 08 00 00 00 75 10 66 90 0f 00 2d d5 0f a9 00 f3 0f 1e fa fb f4 c3 cc cc cc cc 66 0f 1f 84 00 00 00 00 00 90 90 90 90 90 90 90 RSP: 0018:ffffffff8e007ca8 EFLAGS: 00000246 RAX: ffffffff8e0946c0 RBX: ffff88801b6ea064 RCX: 0000000001927111 RDX: 0000000000000001 RSI: ffff88801b6ea000 RDI: ffff88801b6ea064 RBP: 000000000003a3f8 R08: ffff8880b9437d0b R09: 1ffff11017286fa1 R10: dffffc0000000000 R11: ffffffff8b7f4ee0 R12: ffff88801a3b7800 R13: 0000000000000000 R14: 0000000000000001 R15: ffffffff8eab52a0 acpi_idle_enter+0xe4/0x140 drivers/acpi/processor_idle.c:707 cpuidle_enter_state+0x112/0x480 drivers/cpuidle/cpuidle.c:267 cpuidle_enter+0x5d/0xa0 drivers/cpuidle/cpuidle.c:388 call_cpuidle kernel/sched/idle.c:155 [inline] cpuidle_idle_call kernel/sched/idle.c:236 [inline] do_idle+0x375/0x5d0 kernel/sched/idle.c:332 cpu_startup_entry+0x42/0x60 kernel/sched/idle.c:430 rest_init+0x2dc/0x300 init/main.c:739 start_kernel+0x47a/0x500 init/main.c:1081 x86_64_start_reservations+0x2a/0x30 arch/x86/kernel/head64.c:507 x86_64_start_kernel+0x99/0xa0 arch/x86/kernel/head64.c:488 common_startup_64+0x13e/0x147 sched: RT throttling activated