rcu: INFO: rcu_preempt detected stalls on CPUs/tasks: rcu: Tasks blocked on level-0 rcu_node (CPUs 0-1): P5872/1:b..l P6420/2:b..l P6432/1:b..l P6437/1:b..l rcu: (detected by 1, t=10502 jiffies, g=14825, q=351 ncpus=2) task:dhcpcd state:R running task stack:24376 pid:6437 tgid:6437 ppid:5465 task_flags:0x400040 flags:0x00080000 Call Trace: context_switch kernel/sched/core.c:5256 [inline] __schedule+0x1480/0x50a0 kernel/sched/core.c:6863 preempt_schedule_irq+0xb5/0x150 kernel/sched/core.c:7190 irqentry_exit+0x5d8/0x660 kernel/entry/common.c:216 asm_sysvec_apic_timer_interrupt+0x1a/0x20 arch/x86/include/asm/idtentry.h:697 RIP: 0010:unwind_next_frame+0x728/0x23d0 arch/x86/kernel/unwind_orc.c:527 Code: 16 00 00 4c 89 e0 48 c1 e8 03 0f b6 04 28 84 c0 0f 85 5a 16 00 00 0f b7 1e c1 eb 0b 80 e3 01 48 8b 44 24 28 0f b6 04 28 84 c0 <4c> 8b 7c 24 78 0f 85 64 16 00 00 48 8b 44 24 18 88 18 0f b7 1e 83 RSP: 0018:ffffc90005156758 EFLAGS: 00000246 RAX: 0000000000000000 RBX: 0000000000000000 RCX: ffffffff8ef9d3e8 RDX: ffffffff8f734550 RSI: ffffffff8f734554 RDI: ffffffff8b3f5700 RBP: dffffc0000000000 R08: 0000000000000001 R09: ffffffff8d5ae8c0 R10: ffffc90005156878 R11: ffffffff81ac4310 R12: ffffffff8f734555 R13: ffffc90005156878 R14: ffffc90005156828 R15: ffffffff81741f55 arch_stack_walk+0x11c/0x150 arch/x86/kernel/stacktrace.c:25 stack_trace_save+0x9c/0xe0 kernel/stacktrace.c:122 kasan_save_stack mm/kasan/common.c:56 [inline] kasan_save_track+0x3e/0x80 mm/kasan/common.c:77 unpoison_slab_object mm/kasan/common.c:339 [inline] __kasan_slab_alloc+0x6c/0x80 mm/kasan/common.c:365 kasan_slab_alloc include/linux/kasan.h:252 [inline] slab_post_alloc_hook mm/slub.c:4953 [inline] kmem_cache_alloc_from_sheaf_noprof+0xa7/0x1a0 mm/slub.c:5570 mas_pop_node lib/maple_tree.c:1086 [inline] mas_new_ma_node lib/maple_tree.c:2140 [inline] mas_mab_to_node lib/maple_tree.c:2163 [inline] mas_spanning_rebalance+0x694/0x2db0 lib/maple_tree.c:2655 mas_rebalance lib/maple_tree.c:2793 [inline] mas_commit_b_node+0xe3e/0x10a0 lib/maple_tree.c:3070 mas_wr_bnode lib/maple_tree.c:3739 [inline] mas_wr_store_entry+0x52a/0x27a0 lib/maple_tree.c:3771 mas_store_gfp+0x682/0x810 lib/maple_tree.c:5138 vma_iter_clear_gfp include/linux/mm.h:1137 [inline] do_vmi_align_munmap+0x2bd/0x450 mm/vma.c:1534 do_vmi_munmap+0x253/0x2e0 mm/vma.c:1587 __vm_munmap+0x207/0x380 mm/vma.c:3203 __do_sys_munmap mm/mmap.c:1077 [inline] __se_sys_munmap mm/mmap.c:1074 [inline] __x64_sys_munmap+0x60/0x70 mm/mmap.c:1074 do_syscall_x64 arch/x86/entry/syscall_64.c:63 [inline] do_syscall_64+0xfa/0xf80 arch/x86/entry/syscall_64.c:94 entry_SYSCALL_64_after_hwframe+0x77/0x7f RIP: 0033:0x7fd4890492e7 RSP: 002b:00007fffdcc7ecb8 EFLAGS: 00000206 ORIG_RAX: 000000000000000b RAX: ffffffffffffffda RBX: 000055d1924623f0 RCX: 00007fd4890492e7 RDX: 0000000000000002 RSI: 0000000000061018 RDI: 00007fd488d79000 RBP: 00007fffdcc7edc0 R08: 0000000000000030 R09: 000055d192462fa0 R10: 00007fffdcc7ebf0 R11: 0000000000000206 R12: 00007fffdcc7ed08 R13: 00007fd48905c000 R14: 000055d1924623f0 R15: 0000000000000000 task:syz.3.127 state:R running task stack:25912 pid:6432 tgid:6431 ppid:5808 task_flags:0x400040 flags:0x00080000 Call Trace: context_switch kernel/sched/core.c:5256 [inline] __schedule+0x1480/0x50a0 kernel/sched/core.c:6863 preempt_schedule_irq+0xb5/0x150 kernel/sched/core.c:7190 irqentry_exit+0x5d8/0x660 kernel/entry/common.c:216 asm_sysvec_apic_timer_interrupt+0x1a/0x20 arch/x86/include/asm/idtentry.h:697 RIP: 0010:__list_del_entry_valid_or_report+0x4/0x190 lib/list_debug.c:46 Code: 4c 89 f1 e8 ee da 9e fc 90 0f 0b 66 66 2e 0f 1f 84 00 00 00 00 00 90 90 90 90 90 90 90 90 90 90 90 90 90 90 90 90 f3 0f 1e fa <41> 57 41 56 41 55 41 54 53 48 89 fb 49 bd 00 00 00 00 00 fc ff df RSP: 0018:ffffc90004adf598 EFLAGS: 00000246 RAX: 14eefa405200a900 RBX: ffffc90004adf620 RCX: 0000000000000000 RDX: 000000009a2c4cf5 RSI: ffffffff8b3f5740 RDI: ffffc90004adf638 RBP: dffffc0000000000 R08: ffffffff8ad5f5d1 R09: ffffffff8d5ae8c0 R10: dffffc0000000000 R11: fffffbfff1db666f R12: ffff888029f09788 R13: ffff888037afaa40 R14: 1ffff9200095bec7 R15: ffffc90004adf638 __list_del_entry_valid include/linux/list.h:132 [inline] __list_del_entry include/linux/list.h:223 [inline] list_del_init include/linux/list.h:295 [inline] finish_wait+0xc7/0x1f0 kernel/sched/wait.c:395 unix_wait_for_peer+0x22f/0x2e0 net/unix/af_unix.c:1620 unix_dgram_sendmsg+0xb6d/0x1840 net/unix/af_unix.c:2250 sock_sendmsg_nosec net/socket.c:727 [inline] __sock_sendmsg+0x21c/0x270 net/socket.c:742 ____sys_sendmsg+0x534/0x810 net/socket.c:2592 ___sys_sendmsg+0x21f/0x2a0 net/socket.c:2646 __sys_sendmmsg+0x22d/0x430 net/socket.c:2735 __do_sys_sendmmsg net/socket.c:2762 [inline] __se_sys_sendmmsg net/socket.c:2759 [inline] __x64_sys_sendmmsg+0xa0/0xc0 net/socket.c:2759 do_syscall_x64 arch/x86/entry/syscall_64.c:63 [inline] do_syscall_64+0xfa/0xf80 arch/x86/entry/syscall_64.c:94 entry_SYSCALL_64_after_hwframe+0x77/0x7f RIP: 0033:0x7fa8fd1cf749 RSP: 002b:00007fa8fb42e038 EFLAGS: 00000246 ORIG_RAX: 0000000000000133 RAX: ffffffffffffffda RBX: 00007fa8fd425fa0 RCX: 00007fa8fd1cf749 RDX: 0000000000000318 RSI: 00002000000bd000 RDI: 0000000000000004 RBP: 00007fa8fd253f91 R08: 0000000000000000 R09: 0000000000000000 R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000 R13: 00007fa8fd426038 R14: 00007fa8fd425fa0 R15: 00007ffed0e0f308 task:syz.2.123 state:R running task stack:25064 pid:6420 tgid:6415 ppid:5799 task_flags:0x400040 flags:0x00080002 Call Trace: context_switch kernel/sched/core.c:5256 [inline] __schedule+0x1480/0x50a0 kernel/sched/core.c:6863 preempt_schedule_common+0x83/0xd0 kernel/sched/core.c:7047 preempt_schedule+0xae/0xc0 kernel/sched/core.c:7071 preempt_schedule_thunk+0x16/0x30 arch/x86/entry/thunk.S:12 __raw_spin_unlock_irqrestore include/linux/spinlock_api_smp.h:152 [inline] _raw_spin_unlock_irqrestore+0xfd/0x110 kernel/locking/spinlock.c:194 unlock_rt_mutex_safe kernel/locking/rtmutex.c:344 [inline] rt_mutex_slowunlock+0x493/0x8a0 kernel/locking/rtmutex.c:1454 spin_unlock include/linux/spinlock_rt.h:105 [inline] __folio_batch_add_and_move+0x5da/0xa90 mm/swap.c:201 wp_page_copy mm/memory.c:3787 [inline] do_wp_page+0x1bdb/0x4970 mm/memory.c:4180 handle_pte_fault mm/memory.c:6289 [inline] __handle_mm_fault mm/memory.c:6411 [inline] handle_mm_fault+0x9f6/0x1330 mm/memory.c:6580 do_user_addr_fault+0x764/0x1380 arch/x86/mm/fault.c:1387 handle_page_fault arch/x86/mm/fault.c:1476 [inline] exc_page_fault+0x82/0x100 arch/x86/mm/fault.c:1532 asm_exc_page_fault+0x26/0x30 arch/x86/include/asm/idtentry.h:618 RIP: 0010:__put_user_nocheck_4+0x3/0x10 arch/x86/lib/putuser.S:104 Code: d9 0f 01 cb 89 01 31 c9 0f 01 ca c3 cc cc cc cc 90 90 90 90 90 90 90 90 90 90 90 90 90 90 90 90 90 90 90 90 90 90 90 0f 01 cb <89> 01 31 c9 0f 01 ca e9 01 51 04 00 90 90 90 90 90 90 90 90 90 90 RSP: 0018:ffffc90004e4f8b8 EFLAGS: 00050202 RAX: 0000000000000000 RBX: 0000000000000000 RCX: 00002000002d2030 RDX: 0000000000000002 RSI: 0000000000000002 RDI: 00000000ffffffff RBP: ffffc90004e4fa30 R08: 0000000000000000 R09: 0000000000000000 R10: dffffc0000000000 R11: fffffbfff1db666f R12: 00002000002d2000 R13: 0000000000000002 R14: 0000000000000000 R15: dffffc0000000000 ____sys_recvmsg+0x298/0x470 net/socket.c:2825 ___sys_recvmsg+0x1b5/0x510 net/socket.c:2854 do_recvmmsg+0x30d/0x770 net/socket.c:2949 __sys_recvmmsg net/socket.c:3023 [inline] __do_sys_recvmmsg net/socket.c:3046 [inline] __se_sys_recvmmsg net/socket.c:3039 [inline] __x64_sys_recvmmsg+0x190/0x240 net/socket.c:3039 do_syscall_x64 arch/x86/entry/syscall_64.c:63 [inline] do_syscall_64+0xfa/0xf80 arch/x86/entry/syscall_64.c:94 entry_SYSCALL_64_after_hwframe+0x77/0x7f RIP: 0033:0x7f6fbffcf749 RSP: 002b:00007f6fbe20d038 EFLAGS: 00000246 ORIG_RAX: 000000000000012b RAX: ffffffffffffffda RBX: 00007f6fc0226090 RCX: 00007f6fbffcf749 RDX: 0000000000010106 RSI: 00002000000000c0 RDI: 0000000000000004 RBP: 00007f6fc0053f91 R08: 0000000000000000 R09: 0000000000000000 R10: 0000000000000002 R11: 0000000000000246 R12: 0000000000000000 R13: 00007f6fc0226128 R14: 00007f6fc0226090 R15: 00007ffef9027c38 task:kworker/0:3 state:R running task stack:19352 pid:5872 tgid:5872 ppid:2 task_flags:0x4208060 flags:0x00080000 Workqueue: events request_firmware_work_func Call Trace: context_switch kernel/sched/core.c:5256 [inline] __schedule+0x1480/0x50a0 kernel/sched/core.c:6863 preempt_schedule_notrace+0xd1/0x110 kernel/sched/core.c:7140 preempt_schedule_notrace_thunk+0x16/0x30 arch/x86/entry/thunk.S:13 rcu_is_watching+0x7f/0xb0 kernel/rcu/tree.c:752 rcu_read_unlock include/linux/rcupdate.h:895 [inline] class_rcu_destructor include/linux/rcupdate.h:1195 [inline] unwind_next_frame+0x1a6d/0x23d0 arch/x86/kernel/unwind_orc.c:695 arch_stack_walk+0x11c/0x150 arch/x86/kernel/stacktrace.c:25 stack_trace_save+0x9c/0xe0 kernel/stacktrace.c:122 kasan_save_stack mm/kasan/common.c:56 [inline] kasan_save_track+0x3e/0x80 mm/kasan/common.c:77 poison_kmalloc_redzone mm/kasan/common.c:397 [inline] __kasan_kmalloc+0x93/0xb0 mm/kasan/common.c:414 kasan_kmalloc include/linux/kasan.h:262 [inline] __do_kmalloc_node mm/slub.c:5657 [inline] __kmalloc_noprof+0x23e/0x7e0 mm/slub.c:5669 kmalloc_noprof include/linux/slab.h:961 [inline] usb_alloc_urb+0x46/0x150 drivers/usb/core/urb.c:75 ath9k_hif_usb_alloc_reg_in_urbs drivers/net/wireless/ath/ath9k/hif_usb.c:982 [inline] ath9k_hif_usb_alloc_urbs+0xbb1/0x1130 drivers/net/wireless/ath/ath9k/hif_usb.c:1048 ath9k_hif_usb_dev_init drivers/net/wireless/ath/ath9k/hif_usb.c:1134 [inline] ath9k_hif_usb_firmware_cb+0x127/0x4c0 drivers/net/wireless/ath/ath9k/hif_usb.c:1267 request_firmware_work_func+0x105/0x1c0 drivers/base/firmware_loader/main.c:1152 process_one_work kernel/workqueue.c:3257 [inline] process_scheduled_works+0xad1/0x1770 kernel/workqueue.c:3340 worker_thread+0x8a0/0xda0 kernel/workqueue.c:3421 kthread+0x711/0x8a0 kernel/kthread.c:463 ret_from_fork+0x599/0xb30 arch/x86/kernel/process.c:158 ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:246 rcu: rcu_preempt kthread starved for 10015 jiffies! g14825 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:27160 pid:18 tgid:18 ppid:2 task_flags:0x208040 flags:0x00080000 Call Trace: context_switch kernel/sched/core.c:5256 [inline] __schedule+0x1480/0x50a0 kernel/sched/core.c:6863 __schedule_loop kernel/sched/core.c:6945 [inline] schedule+0x165/0x360 kernel/sched/core.c:6960 schedule_timeout+0x12b/0x270 kernel/time/sleep_timeout.c:99 rcu_gp_fqs_loop+0x301/0x1540 kernel/rcu/tree.c:2083 rcu_gp_kthread+0x99/0x390 kernel/rcu/tree.c:2285 kthread+0x711/0x8a0 kernel/kthread.c:463 ret_from_fork+0x599/0xb30 arch/x86/kernel/process.c:158 ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:246 rcu: Stack dump where RCU GP kthread last ran: CPU: 1 UID: 0 PID: 0 Comm: swapper/1 Not tainted syzkaller #0 PREEMPT_{RT,(full)} Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 10/25/2025 RIP: 0010:pv_native_safe_halt+0x13/0x20 arch/x86/kernel/paravirt.c:82 Code: cc cc cc cc cc cc cc 90 90 90 90 90 90 90 90 90 90 90 90 90 90 90 90 f3 0f 1e fa 66 90 0f 00 2d 63 b6 14 00 f3 0f 1e fa fb f4 cc cc cc cc cc cc cc cc cc cc cc cc 90 90 90 90 90 90 90 90 90 RSP: 0018:ffffc900001d7de0 EFLAGS: 000002c2 RAX: 6c3d640d024a2700 RBX: ffffffff819654fa RCX: 6c3d640d024a2700 RDX: 0000000000000001 RSI: ffffffff8ce0c048 RDI: ffffffff8b3f5760 RBP: ffffc900001d7f10 R08: ffff8880b8933c5b R09: 1ffff1101712678b R10: dffffc0000000000 R11: ffffed101712678c R12: ffffffff8edb3370 R13: 1ffff11003757b58 R14: 0000000000000001 R15: 0000000000000001 FS: 0000000000000000(0000) GS:ffff888126e01000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: 00007f99d5584830 CR3: 000000001082a000 CR4: 00000000003526f0 Call Trace: arch_safe_halt arch/x86/include/asm/paravirt.h:107 [inline] default_idle+0x13/0x20 arch/x86/kernel/process.c:767 default_idle_call+0x73/0xb0 kernel/sched/idle.c:122 cpuidle_idle_call kernel/sched/idle.c:191 [inline] do_idle+0x1ea/0x520 kernel/sched/idle.c:332 cpu_startup_entry+0x44/0x60 kernel/sched/idle.c:430 start_secondary+0x101/0x110 arch/x86/kernel/smpboot.c:312 common_startup_64+0x13e/0x147