rcu: INFO: rcu_preempt detected stalls on CPUs/tasks: rcu: Tasks blocked on level-0 rcu_node (CPUs 0-1): P12776/1:b..l P12772/1:b..l rcu: (detected by 0, t=10503 jiffies, g=45793, q=1724 ncpus=2) task:modprobe state:R running task stack:23072 pid:12772 tgid:12772 ppid:6769 flags:0x00004002 Call Trace: context_switch kernel/sched/core.c:5328 [inline] __schedule+0x17fa/0x4bd0 kernel/sched/core.c:6690 preempt_schedule_common+0x84/0xd0 kernel/sched/core.c:6869 preempt_schedule+0xe1/0xf0 kernel/sched/core.c:6893 preempt_schedule_thunk+0x1a/0x30 arch/x86/entry/thunk.S:12 unwind_next_frame+0x18f8/0x22d0 arch/x86/kernel/unwind_orc.c:672 arch_stack_walk+0x11c/0x150 arch/x86/kernel/stacktrace.c:25 stack_trace_save+0x118/0x1d0 kernel/stacktrace.c:122 save_stack+0xfb/0x1f0 mm/page_owner.c:156 __reset_page_owner+0x76/0x430 mm/page_owner.c:297 reset_page_owner include/linux/page_owner.h:25 [inline] free_pages_prepare mm/page_alloc.c:1108 [inline] free_unref_page+0xcd0/0xf00 mm/page_alloc.c:2638 discard_slab mm/slub.c:2677 [inline] __put_partials+0xeb/0x130 mm/slub.c:3145 put_cpu_partial+0x17c/0x250 mm/slub.c:3220 __slab_free+0x2ea/0x3d0 mm/slub.c:4449 qlink_free mm/kasan/quarantine.c:163 [inline] qlist_free_all+0x9a/0x140 mm/kasan/quarantine.c:179 kasan_quarantine_reduce+0x14f/0x170 mm/kasan/quarantine.c:286 __kasan_slab_alloc+0x23/0x80 mm/kasan/common.c:329 kasan_slab_alloc include/linux/kasan.h:247 [inline] slab_post_alloc_hook mm/slub.c:4085 [inline] kmem_cache_alloc_bulk_noprof+0x4fa/0x7c0 mm/slub.c:4975 mt_alloc_bulk lib/maple_tree.c:167 [inline] mas_alloc_nodes+0x3d5/0x840 lib/maple_tree.c:1263 mas_node_count_gfp lib/maple_tree.c:1321 [inline] mas_preallocate+0x554/0x8c0 lib/maple_tree.c:5546 vma_iter_prealloc mm/vma.h:440 [inline] __split_vma+0x302/0xc50 mm/vma.c:397 split_vma mm/vma.c:460 [inline] vma_modify+0x153a/0x1a80 mm/vma.c:1440 vma_modify_flags+0x3a5/0x430 mm/vma.c:1458 mprotect_fixup+0x45a/0xaa0 mm/mprotect.c:664 do_mprotect_pkey+0x8d4/0xd70 mm/mprotect.c:838 __do_sys_mprotect mm/mprotect.c:859 [inline] __se_sys_mprotect mm/mprotect.c:856 [inline] __x64_sys_mprotect+0x80/0x90 mm/mprotect.c:856 do_syscall_x64 arch/x86/entry/common.c:52 [inline] do_syscall_64+0xf3/0x230 arch/x86/entry/common.c:83 entry_SYSCALL_64_after_hwframe+0x77/0x7f RIP: 0033:0x7f7f384a4bb7 RSP: 002b:00007ffdb514fdb8 EFLAGS: 00000206 ORIG_RAX: 000000000000000a RAX: ffffffffffffffda RBX: 00007f7f38481fc0 RCX: 00007f7f384a4bb7 RDX: 0000000000000001 RSI: 0000000000001000 RDI: 00007f7f381f9000 RBP: 00007ffdb514fed0 R08: 00007ffdb514fd48 R09: 00007f7f384815c0 R10: 00007f7f381d8168 R11: 0000000000000206 R12: 00007f7f38481fc0 R13: 00007f7f384aceda R14: 00007f7f381f9f40 R15: 00007f7f381f9740 task:modprobe state:R running task stack:23072 pid:12776 tgid:12776 ppid:35 flags:0x00000002 Call Trace: context_switch kernel/sched/core.c:5328 [inline] __schedule+0x17fa/0x4bd0 kernel/sched/core.c:6690 preempt_schedule_irq+0xfb/0x1c0 kernel/sched/core.c:7012 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+0x0/0x550 kernel/locking/lockdep.c:5793 Code: 05 7d 90 93 7e a9 00 ff ff 00 0f 95 c0 c3 cc cc cc cc 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 55 48 89 e5 41 57 41 56 41 55 41 54 53 48 83 e4 e0 48 RSP: 0018:ffffc9000ab575f8 EFLAGS: 00000246 RAX: 0000000000000001 RBX: ffffea0001a8da00 RCX: 0000000000000002 RDX: 0000000000000000 RSI: 0000000000000000 RDI: ffffffff8e937da0 RBP: dffffc0000000000 R08: 0000000000000000 R09: 0000000000000000 R10: dffffc0000000000 R11: ffffed100c64ebdc R12: 0000000000000000 R13: 1ffffd4000351b40 R14: ffffffff82084b90 R15: ffffea0001a8da00 rcu_lock_acquire include/linux/rcupdate.h:337 [inline] rcu_read_lock include/linux/rcupdate.h:849 [inline] page_ext_get+0x3d/0x2a0 mm/page_ext.c:525 __page_table_check_zero+0xb1/0x350 mm/page_table_check.c:148 page_table_check_free include/linux/page_table_check.h:41 [inline] free_pages_prepare mm/page_alloc.c:1109 [inline] free_unref_page+0xce4/0xf00 mm/page_alloc.c:2638 discard_slab mm/slub.c:2677 [inline] __put_partials+0xeb/0x130 mm/slub.c:3145 put_cpu_partial+0x17c/0x250 mm/slub.c:3220 __slab_free+0x2ea/0x3d0 mm/slub.c:4449 qlink_free mm/kasan/quarantine.c:163 [inline] qlist_free_all+0x9a/0x140 mm/kasan/quarantine.c:179 kasan_quarantine_reduce+0x14f/0x170 mm/kasan/quarantine.c:286 __kasan_slab_alloc+0x23/0x80 mm/kasan/common.c:329 kasan_slab_alloc include/linux/kasan.h:247 [inline] slab_post_alloc_hook mm/slub.c:4085 [inline] slab_alloc_node mm/slub.c:4134 [inline] kmem_cache_alloc_noprof+0x135/0x2a0 mm/slub.c:4141 alloc_empty_file+0x9e/0x1d0 fs/file_table.c:209 path_openat+0x107/0x3590 fs/namei.c:3919 do_filp_open+0x235/0x490 fs/namei.c:3960 do_sys_openat2+0x13e/0x1d0 fs/open.c:1415 do_sys_open fs/open.c:1430 [inline] __do_sys_openat fs/open.c:1446 [inline] __se_sys_openat fs/open.c:1441 [inline] __x64_sys_openat+0x247/0x2a0 fs/open.c:1441 do_syscall_x64 arch/x86/entry/common.c:52 [inline] do_syscall_64+0xf3/0x230 arch/x86/entry/common.c:83 entry_SYSCALL_64_after_hwframe+0x77/0x7f RIP: 0033:0x7f04671b49a4 RSP: 002b:00007ffcd7e093a0 EFLAGS: 00000246 ORIG_RAX: 0000000000000101 RAX: ffffffffffffffda RBX: 0000000000000008 RCX: 00007f04671b49a4 RDX: 0000000000080000 RSI: 00007f04670d1707 RDI: 00000000ffffff9c RBP: 00007f04670d1707 R08: 0000000000000008 R09: 0000000000000001 R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000080000 R13: 00007f04670d17fc R14: 0000000000000001 R15: 0000000000000000 rcu: rcu_preempt kthread starved for 9535 jiffies! g45793 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:24272 pid:17 tgid:17 ppid:2 flags:0x00004000 Call Trace: context_switch kernel/sched/core.c:5328 [inline] __schedule+0x17fa/0x4bd0 kernel/sched/core.c:6690 __schedule_loop kernel/sched/core.c:6767 [inline] schedule+0x14b/0x320 kernel/sched/core.c:6782 schedule_timeout+0x1be/0x310 kernel/time/timer.c:2615 rcu_gp_fqs_loop+0x2df/0x1330 kernel/rcu/tree.c:2045 rcu_gp_kthread+0xa7/0x3b0 kernel/rcu/tree.c:2247 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 0 to CPUs 1: NMI backtrace for cpu 1 CPU: 1 UID: 0 PID: 24 Comm: ksoftirqd/1 Not tainted 6.12.0-rc6-syzkaller-00279-gde2f378f2b77 #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 10/30/2024 RIP: 0010:native_safe_halt arch/x86/include/asm/irqflags.h:48 [inline] RIP: 0010:arch_safe_halt arch/x86/include/asm/irqflags.h:106 [inline] RIP: 0010:kvm_wait+0x250/0x2c0 arch/x86/kernel/kvm.c:1064 Code: 3b 45 0f b6 f6 44 89 ff 44 89 f6 e8 6a 33 54 00 e8 d5 f9 5b 00 45 38 f7 75 15 66 90 e8 d9 32 54 00 0f 00 2d 72 8d c7 0a fb f4 50 fe ff ff e8 c6 32 54 00 fb e9 45 fe ff ff 89 d9 80 e1 07 38 RSP: 0018:ffffc900001e6ee0 EFLAGS: 00000246 RAX: ffffffff8140a727 RBX: ffff888059878900 RCX: ffff88801da88000 RDX: 0000000000000100 RSI: ffffffff8c0acac0 RDI: ffffffff8c6035e0 RBP: ffffc900001e6fb0 R08: ffffffff94298987 R09: 1ffffffff2853130 R10: dffffc0000000000 R11: fffffbfff2853131 R12: 1ffff9200003cde0 R13: dffffc0000000000 R14: 0000000000000003 R15: 0000000000000003 FS: 0000000000000000(0000) GS:ffff8880b8700000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: 00007f6797f09178 CR3: 00000000351e6000 CR4: 00000000003526f0 DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000 DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400 Call Trace: pv_wait arch/x86/include/asm/paravirt.h:596 [inline] pv_wait_head_or_lock kernel/locking/qspinlock_paravirt.h:466 [inline] __pv_queued_spin_lock_slowpath+0x8d0/0xdb0 kernel/locking/qspinlock.c:508 pv_queued_spin_lock_slowpath arch/x86/include/asm/paravirt.h:584 [inline] queued_spin_lock_slowpath+0x42/0x50 arch/x86/include/asm/qspinlock.h:51 queued_spin_lock include/asm-generic/qspinlock.h:114 [inline] do_raw_spin_lock+0x272/0x370 kernel/locking/spinlock_debug.c:116 spin_lock include/linux/spinlock.h:351 [inline] __netif_tx_lock include/linux/netdevice.h:4371 [inline] __dev_queue_xmit+0x17ca/0x3ed0 net/core/dev.c:4428 dev_queue_xmit include/linux/netdevice.h:3094 [inline] can_send+0x8b3/0xcd0 net/can/af_can.c:276 can_can_gw_rcv+0xde7/0x1070 net/can/gw.c:561 deliver net/can/af_can.c:572 [inline] can_rcv_filter+0x20b/0x7f0 net/can/af_can.c:590 can_receive+0x31c/0x470 net/can/af_can.c:663 can_rcv+0x144/0x260 net/can/af_can.c:687 __netif_receive_skb_one_core net/core/dev.c:5670 [inline] __netif_receive_skb+0x2e0/0x650 net/core/dev.c:5783 process_backlog+0x662/0x15b0 net/core/dev.c:6115 __napi_poll+0xcb/0x490 net/core/dev.c:6779 napi_poll net/core/dev.c:6848 [inline] net_rx_action+0x89b/0x1240 net/core/dev.c:6970 handle_softirqs+0x2c5/0x980 kernel/softirq.c:554 run_ksoftirqd+0xca/0x130 kernel/softirq.c:927 smpboot_thread_fn+0x544/0xa30 kernel/smpboot.c:164 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