rcu: INFO: rcu_preempt detected stalls on CPUs/tasks: rcu: Tasks blocked on level-0 rcu_node (CPUs 0-1): P18433/1:b..l rcu: (detected by 0, t=10502 jiffies, g=51157, q=386 ncpus=2) task:syz.3.2190 state:R running task stack:25808 pid:18433 tgid:18431 ppid:5814 task_flags:0x400040 flags:0x00004006 Call Trace: context_switch kernel/sched/core.c:5378 [inline] __schedule+0xf43/0x5890 kernel/sched/core.c:6765 preempt_schedule_irq+0x51/0x90 kernel/sched/core.c:7087 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:get_current arch/x86/include/asm/current.h:49 [inline] RIP: 0010:__rcu_read_lock+0x8d/0xf0 kernel/rcu/tree_plugin.h:416 Code: ea 03 0f b6 14 02 48 89 f8 83 e0 07 83 c3 01 83 c0 03 38 d0 7c 04 84 d2 75 61 48 b8 00 00 00 00 00 fc ff df 89 9d 44 04 00 00 <65> 48 8b 1d 0b 57 64 7e 48 8d bb 44 04 00 00 48 89 fa 48 c1 ea 03 RSP: 0018:ffffc9000f39f820 EFLAGS: 00000246 RAX: dffffc0000000000 RBX: 0000000000000001 RCX: ffffc9000db4f000 RDX: 0000000000000000 RSI: ffffffff820327a8 RDI: ffff88802470ccc4 RBP: ffff88802470c880 R08: 0000000000000005 R09: 0000000000000000 R10: 0000000000000000 R11: 0000000000000003 R12: ffff88802a2ae400 R13: ffff88805e99e4f8 R14: 0000000000000000 R15: ffff88802470c880 rcu_read_lock include/linux/rcupdate.h:847 [inline] count_memcg_events_mm.constprop.0+0x1d/0x340 include/linux/memcontrol.h:990 count_memcg_event_mm include/linux/memcontrol.h:1000 [inline] mm_account_fault mm/memory.c:6065 [inline] handle_mm_fault+0x5cc/0xaa0 mm/memory.c:6226 do_user_addr_fault+0x7a3/0x13f0 arch/x86/mm/fault.c:1388 handle_page_fault arch/x86/mm/fault.c:1480 [inline] exc_page_fault+0x5c/0xc0 arch/x86/mm/fault.c:1538 asm_exc_page_fault+0x26/0x30 arch/x86/include/asm/idtentry.h:623 RIP: 0010:__put_user_nocheck_4+0x7/0x20 arch/x86/lib/putuser.S:97 Code: d9 0f 01 cb 89 01 31 c9 0f 01 ca c3 cc cc cc cc 0f 1f 00 90 90 90 90 90 90 90 90 90 90 90 90 90 90 90 90 f3 0f 1e fa 0f 01 cb <89> 01 31 c9 0f 01 ca c3 cc cc cc cc 66 66 2e 0f 1f 84 00 00 00 00 RSP: 0018:ffffc9000f39f9f8 EFLAGS: 00050246 RAX: 0000000000000000 RBX: 0000000000000000 RCX: 0000400000382030 RDX: 0000000000080000 RSI: ffffffff89288444 RDI: 0000000000000005 RBP: ffffc9000f39fd98 R08: 0000000000000005 R09: 0000000000000000 R10: 0000000000000002 R11: 0000000000000000 R12: 0000000000000000 R13: 0000400000382000 R14: ffffc9000f39fddc R15: 0000000000000002 ____sys_recvmsg+0x2ef/0x6b0 net/socket.c:2806 ___sys_recvmsg+0x115/0x1a0 net/socket.c:2835 do_recvmmsg+0x2f8/0x740 net/socket.c:2930 __sys_recvmmsg net/socket.c:3004 [inline] __do_sys_recvmmsg net/socket.c:3027 [inline] __se_sys_recvmmsg net/socket.c:3020 [inline] __x64_sys_recvmmsg+0x239/0x290 net/socket.c:3020 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: 0033:0x7f1b2bb8d169 RSP: 002b:00007f1b2c990038 EFLAGS: 00000246 ORIG_RAX: 000000000000012b RAX: ffffffffffffffda RBX: 00007f1b2bda6080 RCX: 00007f1b2bb8d169 RDX: 0000000000010106 RSI: 00004000000000c0 RDI: 0000000000000003 RBP: 00007f1b2bc0e2a0 R08: 0000000000000000 R09: 0000000000000000 R10: 0000000000000002 R11: 0000000000000246 R12: 0000000000000000 R13: 0000000000000001 R14: 00007f1b2bda6080 R15: 00007ffd6879a1e8 rcu: rcu_preempt kthread starved for 6506 jiffies! g51157 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:26960 pid:18 tgid:18 ppid:2 task_flags:0x208040 flags:0x00004000 Call Trace: context_switch kernel/sched/core.c:5378 [inline] __schedule+0xf43/0x5890 kernel/sched/core.c:6765 __schedule_loop kernel/sched/core.c:6842 [inline] schedule+0xe7/0x350 kernel/sched/core.c:6857 schedule_timeout+0x124/0x280 kernel/time/sleep_timeout.c:99 rcu_gp_fqs_loop+0x1eb/0xb00 kernel/rcu/tree.c:2024 rcu_gp_kthread+0x271/0x380 kernel/rcu/tree.c:2226 kthread+0x3af/0x750 kernel/kthread.c:464 ret_from_fork+0x45/0x80 arch/x86/kernel/process.c:148 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: 0 Comm: swapper/0 Not tainted 6.14.0-rc7-syzkaller-00074-ga7f2e10ecd8f #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 02/12/2025 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:92 [inline] RIP: 0010:acpi_safe_halt+0x1a/0x20 drivers/acpi/processor_idle.c:112 Code: 90 90 90 90 90 90 90 90 90 90 90 90 90 90 90 90 65 48 8b 05 08 38 ac 74 48 8b 00 a8 08 75 0c 66 90 0f 00 2d f8 1b 87 00 fb f4 c3 cc cc cc cc 90 90 90 90 90 90 90 90 90 90 90 90 90 90 90 90 RSP: 0018:ffffffff8de07d70 EFLAGS: 00000246 RAX: 0000000000004000 RBX: 0000000000000001 RCX: ffffffff8b578469 RDX: 0000000000000001 RSI: ffff888020ac9000 RDI: ffff888020ac9064 RBP: ffff888020ac9064 R08: 0000000000000001 R09: ffffed10170c6f85 R10: ffff8880b8637c2b R11: 0000000000000000 R12: ffff88801f384800 R13: ffffffff8ee2eba0 R14: 0000000000000000 R15: 0000000000000000 FS: 0000000000000000(0000) GS:ffff8880b8600000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: 00007f81735356c0 CR3: 0000000030bf8000 CR4: 00000000003526f0 DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000 DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400 Call Trace: acpi_idle_enter+0xc5/0x160 drivers/acpi/processor_idle.c:699 cpuidle_enter_state+0xaa/0x4f0 drivers/cpuidle/cpuidle.c:268 cpuidle_enter+0x4e/0xa0 drivers/cpuidle/cpuidle.c:389 cpuidle_idle_call kernel/sched/idle.c:230 [inline] do_idle+0x310/0x3f0 kernel/sched/idle.c:325 cpu_startup_entry+0x4f/0x60 kernel/sched/idle.c:423 rest_init+0x16b/0x2b0 init/main.c:743 start_kernel+0x3e9/0x4d0 init/main.c:1099 x86_64_start_reservations+0x18/0x30 arch/x86/kernel/head64.c:515 x86_64_start_kernel+0xb2/0xc0 arch/x86/kernel/head64.c:496 common_startup_64+0x13e/0x148