rcu: INFO: rcu_preempt detected stalls on CPUs/tasks: rcu: Tasks blocked on level-0 rcu_node (CPUs 0-1): P11872/1:b..l P13354/1:b..l rcu: (detected by 1, t=10502 jiffies, g=351313, q=1688 ncpus=2) task:syz.9.6536 state:R running task stack:23712 pid:13354 tgid:13353 ppid:11029 flags:0x00004006 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] kmem_cache_alloc_node_noprof+0x1d9/0x380 mm/slub.c:4220 __alloc_skb+0x1c3/0x440 net/core/skbuff.c:668 alloc_skb include/linux/skbuff.h:1323 [inline] alloc_uevent_skb+0x74/0x230 lib/kobject_uevent.c:289 uevent_net_broadcast_untagged lib/kobject_uevent.c:326 [inline] kobject_uevent_net_broadcast+0x2fd/0x580 lib/kobject_uevent.c:410 kobject_uevent_env+0x57d/0x8e0 lib/kobject_uevent.c:608 device_remove drivers/base/dd.c:567 [inline] __device_release_driver drivers/base/dd.c:1273 [inline] device_release_driver_internal+0x4a9/0x7c0 drivers/base/dd.c:1296 driver_detach+0x1fb/0x2d0 drivers/base/dd.c:1359 bus_remove_driver+0x1f3/0x320 drivers/base/bus.c:744 usb_gadget_unregister_driver+0x4e/0x70 drivers/usb/gadget/udc/core.c:1732 raw_release+0xf6/0x1e0 drivers/usb/gadget/legacy/raw_gadget.c:462 __fput+0x23c/0xa50 fs/file_table.c:450 task_work_run+0x24f/0x310 kernel/task_work.c:239 exit_task_work include/linux/task_work.h:43 [inline] do_exit+0xa2a/0x28e0 kernel/exit.c:938 do_group_exit+0x207/0x2c0 kernel/exit.c:1087 get_signal+0x16b2/0x1750 kernel/signal.c:3017 arch_do_signal_or_restart+0x96/0x860 arch/x86/kernel/signal.c:337 exit_to_user_mode_loop kernel/entry/common.c:111 [inline] exit_to_user_mode_prepare include/linux/entry-common.h:329 [inline] __syscall_exit_to_user_mode_work kernel/entry/common.c:207 [inline] syscall_exit_to_user_mode+0xce/0x340 kernel/entry/common.c:218 do_syscall_64+0x100/0x230 arch/x86/entry/common.c:89 entry_SYSCALL_64_after_hwframe+0x77/0x7f RIP: 0033:0x7f8c4dd8592b RSP: 002b:00007f8c4ebe8f10 EFLAGS: 00000246 ORIG_RAX: 0000000000000010 RAX: fffffffffffffffc RBX: 0000000000000006 RCX: 00007f8c4dd8592b RDX: 00007f8c4ebe9fe0 RSI: 0000000080085502 RDI: 0000000000000006 RBP: 00007f8c4ebe9fe0 R08: 0000000000000080 R09: 00007f8c4ebe8fd8 R10: 0000000000000000 R11: 0000000000000246 R12: 0000000080085502 R13: 0000000800000000 R14: 0000000000000008 R15: 00007f8c4de0bd68 task:syz-executor state:R running task stack:20544 pid:11872 tgid:11872 ppid:11861 flags:0x00000000 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:__kasan_check_read+0x0/0x20 mm/kasan/shadow.c:30 Code: 8e 4c 89 fe e8 c1 17 01 ff 31 db eb d0 66 2e 0f 1f 84 00 00 00 00 00 0f 1f 00 90 90 90 90 90 90 90 90 90 90 90 90 90 90 90 90 0f 1e fa 89 f6 48 8b 0c 24 31 d2 e9 6f e6 ff ff 66 2e 0f 1f 84 RSP: 0018:ffffc9000500f728 EFLAGS: 00000282 RAX: 0000000000000000 RBX: 0000000000000000 RCX: ffffffff82117b8e RDX: ffff88803014da00 RSI: 0000000000000004 RDI: ffff88801e1a6bbc RBP: ffff88801e1a6bbc R08: ffffffff82117ba9 R09: 1ffff11003c34d77 R10: dffffc0000000000 R11: ffffed1003c34d78 R12: ffff88801e1a6b70 R13: 1ffffffff34839dc R14: 0000000000000003 R15: 0000000000000003 instrument_atomic_read include/linux/instrumented.h:68 [inline] atomic_read include/linux/atomic/atomic-instrumented.h:32 [inline] __page_table_check_zero+0x172/0x350 mm/page_table_check.c:157 page_table_check_free include/linux/page_table_check.h:41 [inline] free_pages_prepare mm/page_alloc.c:1128 [inline] free_unref_page+0xd53/0x1010 mm/page_alloc.c:2659 __slab_free+0x2c2/0x380 mm/slub.c:4524 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_kmalloc+0x23/0xb0 mm/kasan/common.c:385 kasan_kmalloc include/linux/kasan.h:260 [inline] __do_kmalloc_node mm/slub.c:4298 [inline] __kmalloc_noprof+0x285/0x4c0 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 tomoyo_path_unlink+0xd0/0x110 security/tomoyo/tomoyo.c:162 security_path_unlink+0x169/0x360 security/security.c:1960 do_unlinkat+0x3e6/0x830 fs/namei.c:4584 __do_sys_unlink fs/namei.c:4635 [inline] __se_sys_unlink fs/namei.c:4633 [inline] __x64_sys_unlink+0x47/0x50 fs/namei.c:4633 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: 0033:0x7f06b2d852d7 RSP: 002b:00007f06b309ecc8 EFLAGS: 00000206 ORIG_RAX: 0000000000000057 RAX: ffffffffffffffda RBX: 0000000000000000 RCX: 00007f06b2d852d7 RDX: 00007f06b309ecf0 RSI: 00007f06b309ed80 RDI: 00007f06b309ed80 RBP: 00007f06b309ed80 R08: 0000000000000000 R09: 0000000000000000 R10: 0000000000000100 R11: 0000000000000206 R12: 00007f06b309fe00 R13: 00007f06b2e018f4 R14: 00007f06b309fe40 R15: 000000000000003e rcu: rcu_preempt kthread starved for 10497 jiffies! g351313 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:25904 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: 1 UID: 0 PID: 3398 Comm: kworker/R-bat_e Not tainted 6.13.0-rc7-syzkaller-00043-g619f0b6fad52 #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 12/27/2024 Workqueue: 0x0 (bat_events) RIP: 0010:kthread_set_per_cpu+0x0/0x1c0 kernel/kthread.c:589 Code: 0d ff ff ff 48 89 ef e8 1e 59 9b 00 e9 00 ff ff ff 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 <66> 0f 1f 00 55 41 57 41 56 41 55 41 54 53 41 89 f6 48 89 fb 48 bd RSP: 0018:ffffc9000cacfd10 EFLAGS: 00000246 RAX: ffffffff816965dd RBX: 0000000000000001 RCX: ffff8880314c5a00 RDX: 0000000000000000 RSI: 00000000ffffffff RDI: ffff8880314c5a00 RBP: ffffc9000cacfed0 R08: ffffffff816965d0 R09: 1ffffffff2033076 R10: dffffc0000000000 R11: fffffbfff2033077 R12: 1ffff11005f618aa R13: ffff8880314c5a18 R14: ffff88802fb0c550 R15: dffffc0000000000 FS: 0000000000000000(0000) GS:ffff8880b8700000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: 00007f173ec9ecdc CR3: 000000006ed8c000 CR4: 00000000003526f0 Call Trace: unbind_worker+0x9b/0x180 kernel/workqueue.c:2703 detach_worker kernel/workqueue.c:2715 [inline] worker_detach_from_pool kernel/workqueue.c:2735 [inline] rescuer_thread+0xb60/0x10a0 kernel/workqueue.c:3533 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 GRED: Unable to relocate VQ 0x0 after dequeue, screwing up backlog GRED: Unable to relocate VQ 0x0 after dequeue, screwing up backlog GRED: Unable to relocate VQ 0x0 after dequeue, screwing up backlog GRED: Unable to relocate VQ 0x0 after dequeue, screwing up backlog