rcu: INFO: rcu_preempt detected stalls on CPUs/tasks: rcu: Tasks blocked on level-0 rcu_node (CPUs 0-1): P3627/1:b..l P3002/1:b..l P3759/1:b..l (detected by 1, t=10502 jiffies, g=7237, q=26 ncpus=2) task:syz-executor state:R running task stack:28440 pid:3759 ppid:3553 flags:0x00004000 Call Trace: context_switch kernel/sched/core.c:5245 [inline] __schedule+0x142d/0x4550 kernel/sched/core.c:6558 preempt_schedule_irq+0xf7/0x1c0 kernel/sched/core.c:6870 irqentry_exit+0x53/0x80 kernel/entry/common.c:439 asm_sysvec_apic_timer_interrupt+0x16/0x20 arch/x86/include/asm/idtentry.h:653 RIP: 0010:lock_acquire+0x26f/0x5a0 kernel/locking/lockdep.c:5666 Code: 2b 00 74 08 4c 89 f7 e8 ef ae 77 00 f6 44 24 61 02 0f 85 84 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:ffffc90004bc7920 EFLAGS: 00000206 RAX: 0000000000000001 RBX: 1ffff92000978f30 RCX: 1ffff92000978ed0 RDX: dffffc0000000000 RSI: ffffffff8aec13c0 RDI: ffffffff8b3d47e0 RBP: ffffc90004bc7a68 R08: dffffc0000000000 R09: fffffbfff2093845 R10: 0000000000000000 R11: dffffc0000000001 R12: 1ffff92000978f2c R13: dffffc0000000000 R14: ffffc90004bc7980 R15: 0000000000000246 rcu_lock_acquire include/linux/rcupdate.h:350 [inline] rcu_read_lock include/linux/rcupdate.h:791 [inline] count_memcg_event_mm+0xad/0x410 include/linux/memcontrol.h:1095 handle_mm_fault+0x15b/0x5340 mm/memory.c:5254 do_user_addr_fault arch/x86/mm/fault.c:1340 [inline] handle_page_fault arch/x86/mm/fault.c:1431 [inline] exc_page_fault+0x26f/0x620 arch/x86/mm/fault.c:1487 asm_exc_page_fault+0x22/0x30 arch/x86/include/asm/idtentry.h:570 RIP: 0010:__put_user_nocheck_4+0x3/0x11 Code: 00 00 48 39 d9 73 54 0f 01 cb 66 89 01 31 c9 0f 01 ca c3 0f 1f 44 00 00 48 bb fd ef ff ff ff 7f 00 00 48 39 d9 73 34 0f 01 cb <89> 01 31 c9 0f 01 ca c3 66 0f 1f 44 00 00 48 bb f9 ef ff ff ff 7f RSP: 0018:ffffc90004bc7f28 EFLAGS: 00050293 RAX: 0000000000000017 RBX: 00007fffffffeffd RCX: 00005555570f97d0 RDX: 0000000000000000 RSI: ffffffff8aec13c0 RDI: ffffffff8b3d47e0 RBP: ffff888020ae2450 R08: dffffc0000000000 R09: fffffbfff1ce702e R10: 0000000000000000 R11: dffffc0000000001 R12: 0000000000000000 R13: 0000000000000000 R14: 0000000000000017 R15: dffffc0000000000 schedule_tail+0x91/0xb0 kernel/sched/core.c:5184 ret_from_fork+0x8/0x30 arch/x86/entry/entry_64.S:293 task:udevd state:R running task stack:24688 pid:3002 ppid:1 flags:0x00004002 Call Trace: context_switch kernel/sched/core.c:5245 [inline] __schedule+0x142d/0x4550 kernel/sched/core.c:6558 preempt_schedule_irq+0xf7/0x1c0 kernel/sched/core.c:6870 irqentry_exit+0x53/0x80 kernel/entry/common.c:439 asm_sysvec_apic_timer_interrupt+0x16/0x20 arch/x86/include/asm/idtentry.h:653 RIP: 0010:do___read_seqcount_retry include/linux/seqlock.h:429 [inline] RIP: 0010:do_read_seqcount_retry include/linux/seqlock.h:449 [inline] RIP: 0010:read_seqretry include/linux/seqlock.h:862 [inline] RIP: 0010:__follow_mount_rcu fs/namei.c:1513 [inline] RIP: 0010:handle_mounts fs/namei.c:1534 [inline] RIP: 0010:step_into+0x89e/0x1070 fs/namei.c:1836 Code: 00 00 45 8b 24 24 48 89 d8 48 c1 e8 03 42 0f b6 04 30 84 c0 0f 85 62 01 00 00 44 8b 3b 48 8b 84 24 88 00 00 00 42 0f b6 04 30 <84> c0 0f 85 67 01 00 00 8b 05 b4 25 ec 0a 44 39 f8 0f 85 56 05 00 RSP: 0018:ffffc900031ef680 EFLAGS: 00000246 RAX: 0000000000000000 RBX: ffffc900031efbe8 RCX: ffff88807bdd8000 RDX: ffffc900031efbe4 RSI: 0000000000000000 RDI: 0000000000000000 RBP: ffffc900031ef7d0 R08: ffffffff81f520d4 R09: fffffbfff1ce702e R10: 0000000000000000 R11: dffffc0000000001 R12: 0000000000200000 R13: ffffc900031efba0 R14: dffffc0000000000 R15: 0000000000000764 walk_component fs/namei.c:2004 [inline] link_path_walk+0x72c/0xee0 fs/namei.c:2325 path_openat+0x23d/0x2e60 fs/namei.c:3781 do_filp_open+0x230/0x480 fs/namei.c:3812 do_sys_openat2+0x13b/0x4f0 fs/open.c:1318 do_sys_open fs/open.c:1334 [inline] __do_sys_openat fs/open.c:1350 [inline] __se_sys_openat fs/open.c:1345 [inline] __x64_sys_openat+0x243/0x290 fs/open.c:1345 do_syscall_x64 arch/x86/entry/common.c:51 [inline] do_syscall_64+0x3b/0xb0 arch/x86/entry/common.c:81 entry_SYSCALL_64_after_hwframe+0x68/0xd2 RIP: 0033:0x7f5e5b1169a4 RSP: 002b:00007fff3a4a1bd0 EFLAGS: 00000246 ORIG_RAX: 0000000000000101 RAX: ffffffffffffffda RBX: 0000000000000008 RCX: 00007f5e5b1169a4 RDX: 0000000000080000 RSI: 00007fff3a4a1d08 RDI: 00000000ffffff9c RBP: 00007fff3a4a1d08 R08: 0000000000000008 R09: 0000000000000001 R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000080000 R13: 0000557dd8bb9b42 R14: 0000000000000001 R15: 0000000000000000 task:kworker/u4:5 state:R running task stack:24320 pid:3627 ppid:2 flags:0x00004000 Workqueue: bat_events batadv_nc_worker Call Trace: context_switch kernel/sched/core.c:5245 [inline] __schedule+0x142d/0x4550 kernel/sched/core.c:6558 preempt_schedule_irq+0xf7/0x1c0 kernel/sched/core.c:6870 irqentry_exit+0x53/0x80 kernel/entry/common.c:439 asm_sysvec_apic_timer_interrupt+0x16/0x20 arch/x86/include/asm/idtentry.h:653 RIP: 0010:lock_acquire+0x26f/0x5a0 kernel/locking/lockdep.c:5666 Code: 2b 00 74 08 4c 89 f7 e8 ef ae 77 00 f6 44 24 61 02 0f 85 84 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:ffffc900042bfa80 EFLAGS: 00000206 RAX: 0000000000000001 RBX: 1ffff92000857f5c RCX: 1ffff92000857efc RDX: dffffc0000000000 RSI: ffffffff8aec13c0 RDI: ffffffff8b3d47e0 RBP: ffffc900042bfbe0 R08: dffffc0000000000 R09: fffffbfff2093845 R10: 0000000000000000 R11: dffffc0000000001 R12: 1ffff92000857f58 R13: dffffc0000000000 R14: ffffc900042bfae0 R15: 0000000000000246 rcu_lock_acquire include/linux/rcupdate.h:350 [inline] rcu_read_lock include/linux/rcupdate.h:791 [inline] batadv_nc_purge_orig_hash net/batman-adv/network-coding.c:408 [inline] batadv_nc_worker+0xe8/0x610 net/batman-adv/network-coding.c:719 process_one_work+0x8a9/0x11d0 kernel/workqueue.c:2292 worker_thread+0xa47/0x1200 kernel/workqueue.c:2439 kthread+0x28d/0x320 kernel/kthread.c:376 ret_from_fork+0x1f/0x30 arch/x86/entry/entry_64.S:308 rcu: rcu_preempt kthread starved for 10583 jiffies! g7237 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:27256 pid:16 ppid:2 flags:0x00004000 Call Trace: context_switch kernel/sched/core.c:5245 [inline] __schedule+0x142d/0x4550 kernel/sched/core.c:6558 schedule+0xbf/0x180 kernel/sched/core.c:6634 schedule_timeout+0x1b9/0x300 kernel/time/timer.c:1965 rcu_gp_fqs_loop+0x2d2/0x1150 kernel/rcu/tree.c:1706 rcu_gp_kthread+0xa3/0x3b0 kernel/rcu/tree.c:1905 kthread+0x28d/0x320 kernel/kthread.c:376 ret_from_fork+0x1f/0x30 arch/x86/entry/entry_64.S:308 rcu: Stack dump where RCU GP kthread last ran: CPU: 1 PID: 0 Comm: swapper/1 Not tainted 6.1.98-syzkaller #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 06/07/2024 RIP: 0010:native_save_fl arch/x86/include/asm/irqflags.h:22 [inline] RIP: 0010:arch_local_save_flags arch/x86/include/asm/irqflags.h:70 [inline] RIP: 0010:arch_irqs_disabled arch/x86/include/asm/irqflags.h:130 [inline] RIP: 0010:acpi_safe_halt drivers/acpi/processor_idle.c:113 [inline] RIP: 0010:acpi_idle_do_entry+0x10f/0x340 drivers/acpi/processor_idle.c:572 Code: 27 f5 f6 48 83 e3 08 0f 85 0b 01 00 00 4c 8d 74 24 20 e8 e4 e5 fb f6 0f 1f 44 00 00 e8 3a 23 f5 f6 0f 00 2d 83 f4 b1 00 fb f4 <4c> 89 f3 48 c1 eb 03 42 80 3c 3b 00 74 08 4c 89 f7 e8 5b a7 4c f7 RSP: 0018:ffffc90000177b80 EFLAGS: 000002d3 RAX: ffffffff8a957316 RBX: 0000000000000000 RCX: ffff888012731dc0 RDX: 0000000000000000 RSI: ffffffff8aec0240 RDI: ffffffff8b3d47e0 RBP: ffffc90000177c10 R08: ffffffff8a9572f8 R09: ffffed10024e63b9 R10: 0000000000000000 R11: dffffc0000000001 R12: 1ffff9200002ef70 R13: ffff888017f08004 R14: ffffc90000177ba0 R15: dffffc0000000000 FS: 0000000000000000(0000) GS:ffff8880b9900000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: 0000000000000000 CR3: 000000005d95d000 CR4: 00000000003506e0 DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000 DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400 Call Trace: acpi_idle_enter+0x352/0x4f0 drivers/acpi/processor_idle.c:709 cpuidle_enter_state+0x516/0xf80 drivers/cpuidle/cpuidle.c:239 cpuidle_enter+0x59/0x90 drivers/cpuidle/cpuidle.c:356 call_cpuidle kernel/sched/idle.c:155 [inline] cpuidle_idle_call kernel/sched/idle.c:236 [inline] do_idle+0x3ce/0x680 kernel/sched/idle.c:303 cpu_startup_entry+0x3d/0x60 kernel/sched/idle.c:401 start_secondary+0xe4/0xf0 arch/x86/kernel/smpboot.c:281 secondary_startup_64_no_verify+0xcf/0xdb