rcu: INFO: rcu_preempt detected stalls on CPUs/tasks: rcu: Tasks blocked on level-0 rcu_node (CPUs 0-1): P7449/1:b..l P5829/1:b..l rcu: (detected by 0, t=10503 jiffies, g=15757, q=636 ncpus=2) task:syz-executor state:R running task stack:20216 pid:5829 tgid:5829 ppid:5822 flags:0x00004002 Call Trace: context_switch kernel/sched/core.c:5369 [inline] __schedule+0x1850/0x4c30 kernel/sched/core.c:6756 preempt_schedule_common+0x84/0xd0 kernel/sched/core.c:6935 preempt_schedule+0xe1/0xf0 kernel/sched/core.c:6959 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:1127 [inline] free_unref_page+0xd3f/0x1010 mm/page_alloc.c:2659 discard_slab mm/slub.c:2688 [inline] __put_partials+0x160/0x1c0 mm/slub.c:3157 put_cpu_partial+0x17c/0x250 mm/slub.c:3232 __slab_free+0x290/0x380 mm/slub.c:4483 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:250 [inline] slab_post_alloc_hook mm/slub.c:4119 [inline] slab_alloc_node mm/slub.c:4168 [inline] __do_kmalloc_node mm/slub.c:4297 [inline] __kmalloc_noprof+0x236/0x4c0 mm/slub.c:4310 kmalloc_noprof include/linux/slab.h:905 [inline] kzalloc_noprof include/linux/slab.h:1037 [inline] tomoyo_encode2 security/tomoyo/realpath.c:45 [inline] tomoyo_encode+0x26f/0x540 security/tomoyo/realpath.c:80 tomoyo_realpath_from_path+0x59e/0x5e0 security/tomoyo/realpath.c:283 tomoyo_get_realpath security/tomoyo/file.c:151 [inline] tomoyo_path_perm+0x2b7/0x740 security/tomoyo/file.c:822 security_inode_getattr+0x130/0x330 security/security.c:2372 vfs_getattr+0x2a/0x3b0 fs/stat.c:243 vfs_statx_path fs/stat.c:283 [inline] vfs_statx+0x18c/0x490 fs/stat.c:347 vfs_fstatat+0xe5/0x130 fs/stat.c:366 __do_sys_newfstatat fs/stat.c:530 [inline] __se_sys_newfstatat fs/stat.c:524 [inline] __x64_sys_newfstatat+0x11d/0x1a0 fs/stat.c:524 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: 0033:0x7ff9f8d8453a RSP: 002b:00007ffd36d66c08 EFLAGS: 00000286 ORIG_RAX: 0000000000000106 RAX: ffffffffffffffda RBX: 00007ff9f8e018f4 RCX: 00007ff9f8d8453a RDX: 00007ffd36d66c30 RSI: 00007ffd36d66cc0 RDI: 00000000ffffff9c RBP: 00007ffd36d66cc0 R08: 0000000000000000 R09: 0000000000000000 R10: 0000000000000100 R11: 0000000000000286 R12: 00007ffd36d67d40 R13: 00007ff9f8e018f4 R14: 00007ffd36d67d80 R15: 0000000000000062 task:syz-executor state:R running task stack:27328 pid:7449 tgid:7449 ppid:5815 flags:0x00004002 Call Trace: context_switch kernel/sched/core.c:5369 [inline] __schedule+0x1850/0x4c30 kernel/sched/core.c:6756 preempt_schedule_irq+0xfb/0x1c0 kernel/sched/core.c:7078 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:unwind_get_return_address+0x3b/0x90 arch/x86/kernel/unwind_orc.c:369 Code: 00 00 fc ff df 48 89 f8 48 c1 e8 03 42 0f b6 04 30 84 c0 75 4b 83 3b 00 74 3a 48 83 c3 48 49 89 df 49 c1 ef 03 43 80 3c 37 00 <74> 08 48 89 df e8 5b 30 ba 00 48 8b 3b e8 83 72 1e 00 85 c0 74 14 RSP: 0018:ffffc900054f77c0 EFLAGS: 00000246 RAX: 0000000000000000 RBX: ffffc900054f7828 RCX: 0000000080000000 RDX: dffffc0000000000 RSI: ffffc900054f0000 RDI: ffffc900054f77e0 RBP: ffffc900054f7870 R08: ffffc900054f7f48 R09: 0000000000000000 R10: ffffc900054f7830 R11: fffff52000a9ef08 R12: ffff88801c7ada00 R13: ffffffff818b4a10 R14: dffffc0000000000 R15: 1ffff92000a9ef05 arch_stack_walk+0xfd/0x150 arch/x86/kernel/stacktrace.c:26 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:1127 [inline] free_unref_page+0xd3f/0x1010 mm/page_alloc.c:2659 discard_slab mm/slub.c:2688 [inline] __put_partials+0x160/0x1c0 mm/slub.c:3157 put_cpu_partial+0x17c/0x250 mm/slub.c:3232 __slab_free+0x290/0x380 mm/slub.c:4483 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:250 [inline] slab_post_alloc_hook mm/slub.c:4119 [inline] slab_alloc_node mm/slub.c:4168 [inline] kmem_cache_alloc_noprof+0x1d9/0x380 mm/slub.c:4175 vm_area_alloc+0x24/0x1d0 kernel/fork.c:472 __bprm_mm_init fs/exec.c:259 [inline] bprm_mm_init fs/exec.c:393 [inline] alloc_bprm+0x374/0xa30 fs/exec.c:1544 do_execveat_common+0x18c/0x6f0 fs/exec.c:1900 do_execve fs/exec.c:2023 [inline] __do_sys_execve fs/exec.c:2099 [inline] __se_sys_execve fs/exec.c:2094 [inline] __x64_sys_execve+0x92/0xb0 fs/exec.c:2094 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: 0033:0x7f747c7b93f7 RSP: 002b:00007f747d68fdf8 EFLAGS: 00000206 ORIG_RAX: 000000000000003b RAX: ffffffffffffffda RBX: 00007ffdd75b6ef4 RCX: 00007f747c7b93f7 RDX: 00007ffdd75b48d0 RSI: 00007ffdd75b4b10 RDI: 00007ffdd75b6ef4 RBP: 00007f747d68fe70 R08: 00007f747d68ff20 R09: 0000000000000000 R10: 0000000000000008 R11: 0000000000000206 R12: 00007ffdd75b4b10 R13: 00007ffdd75b48d0 R14: 0000000000000000 R15: 0000000000000000 rcu: rcu_preempt kthread starved for 3240 jiffies! g15757 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:25976 pid:17 tgid:17 ppid:2 flags:0x00004000 Call Trace: context_switch kernel/sched/core.c:5369 [inline] __schedule+0x1850/0x4c30 kernel/sched/core.c:6756 __schedule_loop kernel/sched/core.c:6833 [inline] schedule+0x14b/0x320 kernel/sched/core.c:6848 schedule_timeout+0x15a/0x290 kernel/time/sleep_timeout.c:99 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: CPU: 0 UID: 0 PID: 16 Comm: ksoftirqd/0 Not tainted 6.13.0-rc6-syzkaller-00127-g8c7a6efc017e #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 09/13/2024 RIP: 0010:__raw_spin_unlock_irqrestore include/linux/spinlock_api_smp.h:152 [inline] RIP: 0010:_raw_spin_unlock_irqrestore+0xd8/0x140 kernel/locking/spinlock.c:194 Code: 9c 8f 44 24 20 42 80 3c 23 00 74 08 4c 89 f7 e8 8e 3a 3a f6 f6 44 24 21 02 75 52 41 f7 c7 00 02 00 00 74 01 fb bf 01 00 00 00 43 e5 a1 f5 65 8b 05 a4 28 38 74 85 c0 74 43 48 c7 04 24 0e 36 RSP: 0018:ffffc90000156e60 EFLAGS: 00000206 RAX: 53693f8ea4db8e00 RBX: 1ffff9200002add0 RCX: ffffffff817b378a RDX: dffffc0000000000 RSI: ffffffff8c0a98e0 RDI: 0000000000000001 RBP: ffffc90000156f00 R08: ffffffff942a59cf R09: 1ffffffff2854b39 R10: dffffc0000000000 R11: fffffbfff2854b3a R12: dffffc0000000000 R13: 1ffff9200002adcc R14: ffffc90000156e80 R15: 0000000000000246 FS: 0000000000000000(0000) GS:ffff8880b8600000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: 00005575688e3628 CR3: 000000003469e000 CR4: 00000000003526f0 DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000 DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400 Call Trace: spin_unlock_irqrestore include/linux/spinlock.h:406 [inline] backlog_unlock_irq_restore net/core/dev.c:250 [inline] enqueue_to_backlog+0x8b2/0xc80 net/core/dev.c:4925 netif_rx_internal+0x17a/0x630 net/core/dev.c:5233 netif_rx+0x59/0x90 net/core/dev.c:5286 vxcan_xmit+0x482/0x760 drivers/net/can/vxcan.c:73 __netdev_start_xmit include/linux/netdevice.h:5002 [inline] netdev_start_xmit include/linux/netdevice.h:5011 [inline] xmit_one net/core/dev.c:3620 [inline] dev_hard_start_xmit+0x27a/0x7d0 net/core/dev.c:3636 __dev_queue_xmit+0x1b73/0x3f50 net/core/dev.c:4466 dev_queue_xmit include/linux/netdevice.h:3168 [inline] can_send+0x9a3/0xe20 net/can/af_can.c:277 can_can_gw_rcv+0xde7/0x1070 net/can/gw.c:561 deliver net/can/af_can.c:573 [inline] can_rcv_filter+0x11c/0x7f0 net/can/af_can.c:600 can_receive+0x327/0x480 net/can/af_can.c:664 can_rcv+0x144/0x260 net/can/af_can.c:688 __netif_receive_skb_one_core net/core/dev.c:5704 [inline] __netif_receive_skb+0x2e0/0x650 net/core/dev.c:5817 process_backlog+0x662/0x15b0 net/core/dev.c:6149 __napi_poll+0xcb/0x490 net/core/dev.c:6902 napi_poll net/core/dev.c:6971 [inline] net_rx_action+0x89b/0x1240 net/core/dev.c:7093 handle_softirqs+0x2d4/0x9b0 kernel/softirq.c:561 run_ksoftirqd+0xca/0x130 kernel/softirq.c:950 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