rcu: INFO: rcu_preempt detected stalls on CPUs/tasks: rcu: Tasks blocked on level-0 rcu_node (CPUs 0-1): P7096/1:b..l P7102/1:b..l rcu: (detected by 1, t=10502 jiffies, g=29469, q=517 ncpus=2) task:syz.4.500 state:R running task stack:27216 pid:7102 tgid:7101 ppid:5796 flags:0x00000000 Call Trace: context_switch kernel/sched/core.c:5408 [inline] __schedule+0xf15/0x5d00 kernel/sched/core.c:6745 preempt_schedule_irq+0x51/0x90 kernel/sched/core.c:7067 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:__sanitizer_cov_trace_pc+0x0/0x60 kernel/kcov.c:200 Code: be b0 01 00 00 e8 a0 ff ff ff 31 c0 c3 cc cc cc cc 66 0f 1f 84 00 00 00 00 00 90 90 90 90 90 90 90 90 90 90 90 90 90 90 90 90 0f 1e fa 65 48 8b 15 64 f4 75 7e 65 8b 05 65 f4 75 7e a9 00 01 RSP: 0018:ffffc90003207720 EFLAGS: 00000286 RAX: 0000000000000002 RBX: ffffffff819f1abb RCX: ffffffff81342a2e RDX: ffff888026afbc00 RSI: 0000000000000000 RDI: 0000000000000007 RBP: ffffc900032077c0 R08: 0000000000000007 R09: 0000000000000000 R10: ffffffff819f1abb R11: 0000000000000000 R12: ffffc90003207730 R13: ffffffff81798340 R14: ffffc900032077f0 R15: ffff888026afbc00 arch_stack_walk+0xd8/0x170 arch/x86/kernel/stacktrace.c:27 stack_trace_save+0x95/0xd0 kernel/stacktrace.c:122 save_stack+0x162/0x1f0 mm/page_owner.c:156 __reset_page_owner+0x8d/0x400 mm/page_owner.c:297 reset_page_owner include/linux/page_owner.h:25 [inline] free_pages_prepare mm/page_alloc.c:1093 [inline] free_unref_page+0x64a/0xe40 mm/page_alloc.c:2588 vfree+0x181/0x7a0 mm/vmalloc.c:3355 kvfree+0x33/0x50 mm/util.c:678 htab_map_alloc+0xf33/0x17b0 kernel/bpf/hashtab.c:609 map_create+0x57b/0x1c50 kernel/bpf/syscall.c:1333 __sys_bpf+0xd73/0x49a0 kernel/bpf/syscall.c:5670 __do_sys_bpf kernel/bpf/syscall.c:5795 [inline] __se_sys_bpf kernel/bpf/syscall.c:5793 [inline] __x64_sys_bpf+0x78/0xc0 kernel/bpf/syscall.c:5793 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: 0033:0x7f9500175bd9 RSP: 002b:00007f9500efa048 EFLAGS: 00000246 ORIG_RAX: 0000000000000141 RAX: ffffffffffffffda RBX: 00007f9500303f60 RCX: 00007f9500175bd9 RDX: 0000000000000048 RSI: 0000000020000100 RDI: 0000000000000000 RBP: 00007f95001e4aa1 R08: 0000000000000000 R09: 0000000000000000 R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000 R13: 000000000000000b R14: 00007f9500303f60 R15: 00007ffc411cc918 task:syz.2.497 state:R running task stack:26784 pid:7096 tgid:7091 ppid:6692 flags:0x00004002 Call Trace: context_switch kernel/sched/core.c:5408 [inline] __schedule+0xf15/0x5d00 kernel/sched/core.c:6745 preempt_schedule_common+0x44/0xc0 kernel/sched/core.c:6924 preempt_schedule_thunk+0x1a/0x30 arch/x86/entry/thunk.S:12 unwind_next_frame+0x1c90/0x23a0 arch/x86/kernel/unwind_orc.c:672 arch_stack_walk+0x100/0x170 arch/x86/kernel/stacktrace.c:25 stack_trace_save+0x95/0xd0 kernel/stacktrace.c:122 save_stack+0x162/0x1f0 mm/page_owner.c:156 __reset_page_owner+0x8d/0x400 mm/page_owner.c:297 reset_page_owner include/linux/page_owner.h:25 [inline] free_pages_prepare mm/page_alloc.c:1093 [inline] free_unref_folios+0x991/0x1310 mm/page_alloc.c:2637 folios_put_refs+0x487/0x6d0 mm/swap.c:1024 folio_batch_release include/linux/pagevec.h:101 [inline] mapping_try_invalidate+0x393/0x470 mm/truncate.c:526 drop_pagecache_sb+0xd2/0x290 fs/drop_caches.c:40 iterate_supers+0xfb/0x240 fs/super.c:923 drop_caches_sysctl_handler+0xeb/0x190 fs/drop_caches.c:64 proc_sys_call_handler+0x4cc/0x6f0 fs/proc/proc_sysctl.c:592 iter_file_splice_write+0x906/0x10b0 fs/splice.c:743 do_splice_from fs/splice.c:941 [inline] direct_splice_actor+0x19b/0x6d0 fs/splice.c:1164 splice_direct_to_actor+0x346/0xa40 fs/splice.c:1108 do_splice_direct_actor fs/splice.c:1207 [inline] do_splice_direct+0x17e/0x250 fs/splice.c:1233 do_sendfile+0xb1e/0xe50 fs/read_write.c:1295 __do_sys_sendfile64 fs/read_write.c:1356 [inline] __se_sys_sendfile64 fs/read_write.c:1348 [inline] __x64_sys_sendfile64+0x155/0x220 fs/read_write.c:1348 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: 0033:0x7f8ee9f75bd9 RSP: 002b:00007f8eead1e048 EFLAGS: 00000246 ORIG_RAX: 0000000000000028 RAX: ffffffffffffffda RBX: 00007f8eea104110 RCX: 00007f8ee9f75bd9 RDX: 0000000020002080 RSI: 0000000000000009 RDI: 000000000000000a RBP: 00007f8ee9fe4aa1 R08: 0000000000000000 R09: 0000000000000000 R10: 000000000000023b R11: 0000000000000246 R12: 0000000000000000 R13: 000000000000006e R14: 00007f8eea104110 R15: 00007fff53b54d88 rcu: rcu_preempt kthread starved for 9963 jiffies! g29469 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:25776 pid:17 tgid:17 ppid:2 flags:0x00004000 Call Trace: context_switch kernel/sched/core.c:5408 [inline] __schedule+0xf15/0x5d00 kernel/sched/core.c:6745 __schedule_loop kernel/sched/core.c:6822 [inline] schedule+0xe7/0x350 kernel/sched/core.c:6837 schedule_timeout+0x136/0x2a0 kernel/time/timer.c:2581 rcu_gp_fqs_loop+0x1eb/0xb00 kernel/rcu/tree.c:2000 rcu_gp_kthread+0x271/0x380 kernel/rcu/tree.c:2202 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: 1 PID: 0 Comm: swapper/1 Not tainted 6.10.0-rc6-syzkaller-00212-g1dd28064d416 #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 06/07/2024 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+0x1a/0x20 drivers/acpi/processor_idle.c:113 Code: 90 90 90 90 90 90 90 90 90 90 90 90 90 90 90 90 65 48 8b 05 68 54 1c 75 48 8b 00 a8 08 75 0c 66 90 0f 00 2d 18 ae b3 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:ffffc900001a7d58 EFLAGS: 00000246 RAX: 0000000000004000 RBX: 0000000000000001 RCX: ffffffff8ae767b9 RDX: 0000000000000001 RSI: ffff888019a82000 RDI: ffff888019a82064 RBP: ffff888019a82064 R08: 0000000000000001 R09: ffffed1017266fdd R10: ffff8880b9337eeb R11: 0000000000000000 R12: ffff88801b79b000 R13: ffffffff8e741e00 R14: 0000000000000001 R15: 0000000000000000 FS: 0000000000000000(0000) GS:ffff8880b9300000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: 00007f9e74cdfd90 CR3: 000000002513a000 CR4: 00000000003506f0 DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000 DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400 Call Trace: acpi_idle_enter+0xc5/0x160 drivers/acpi/processor_idle.c:707 cpuidle_enter_state+0x85/0x500 drivers/cpuidle/cpuidle.c:267 cpuidle_enter+0x4e/0xa0 drivers/cpuidle/cpuidle.c:388 cpuidle_idle_call kernel/sched/idle.c:236 [inline] do_idle+0x313/0x3f0 kernel/sched/idle.c:332 cpu_startup_entry+0x4f/0x60 kernel/sched/idle.c:430 start_secondary+0x220/0x2b0 arch/x86/kernel/smpboot.c:313 common_startup_64+0x13e/0x148