rcu: INFO: rcu_preempt detected stalls on CPUs/tasks: rcu: (detected by 1, t=10502 jiffies, g=43685, q=234 ncpus=2) rcu: All QSes seen, last rcu_preempt kthread activity 10427 (4294989519-4294979092), jiffies_till_next_fqs=1, root ->qsmask 0x0 rcu: rcu_preempt kthread starved for 10427 jiffies! g43685 f0x2 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:26296 pid:17 tgid:17 ppid:2 flags:0x00004000 Call Trace: context_switch kernel/sched/core.c:5408 [inline] __schedule+0x17e8/0x4a20 kernel/sched/core.c:6745 __schedule_loop kernel/sched/core.c:6822 [inline] schedule+0x14b/0x320 kernel/sched/core.c:6837 schedule_timeout+0x1be/0x310 kernel/time/timer.c:2581 rcu_gp_fqs_loop+0x2df/0x1330 kernel/rcu/tree.c:2000 rcu_gp_kthread+0xa7/0x3b0 kernel/rcu/tree.c:2202 kthread+0x2f2/0x390 kernel/kthread.c:389 ret_from_fork+0x4d/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 1 to CPUs 0: NMI backtrace for cpu 0 CPU: 0 PID: 10344 Comm: syz.2.1718 Not tainted 6.10.0-rc5-syzkaller-00012-g626737a5791b #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 06/07/2024 RIP: 0010:kcov_remote_start+0x12e/0x7e0 kernel/kcov.c:877 Code: 99 04 00 00 48 c7 c7 e0 c4 37 8e e8 7c 7d fa 09 48 b8 eb 83 b5 80 46 86 c8 61 48 0f af c5 48 c1 e8 3c 4c 8b 3c c5 60 73 7e 94 <4d> 85 ff 74 18 49 83 c7 f0 74 12 49 39 2f 0f 84 8b 00 00 00 4d 8b RSP: 0018:ffffc90000006b10 EFLAGS: 00000013 RAX: 0000000000000004 RBX: ffff888027b25a00 RCX: 0000000000000001 RDX: dffffc0000000000 RSI: 0000000000000004 RDI: ffffc90000006a80 RBP: 0100000000000001 R08: 0000000000000003 R09: fffff52000000d50 R10: dffffc0000000000 R11: fffff52000000d50 R12: ffffffff81962f3e R13: ffff88801bbabf00 R14: 0000000000000006 R15: ffff888024dd2e50 FS: 0000000000000000(0000) GS:ffff8880b9400000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: 0000001b2c506ff8 CR3: 000000007d778000 CR4: 0000000000350ef0 Call Trace: kcov_remote_start_usb include/linux/kcov.h:55 [inline] kcov_remote_start_usb_softirq include/linux/kcov.h:89 [inline] __usb_hcd_giveback_urb+0x405/0x6e0 drivers/usb/core/hcd.c:1649 dummy_timer+0x830/0x45d0 drivers/usb/gadget/udc/dummy_hcd.c:1987 __run_hrtimer kernel/time/hrtimer.c:1687 [inline] __hrtimer_run_queues+0x59d/0xd50 kernel/time/hrtimer.c:1751 hrtimer_interrupt+0x396/0x990 kernel/time/hrtimer.c:1813 local_apic_timer_interrupt arch/x86/kernel/apic/apic.c:1032 [inline] __sysvec_apic_timer_interrupt+0x112/0x3f0 arch/x86/kernel/apic/apic.c:1049 instr_sysvec_apic_timer_interrupt arch/x86/kernel/apic/apic.c:1043 [inline] sysvec_apic_timer_interrupt+0x52/0xc0 arch/x86/kernel/apic/apic.c:1043 asm_sysvec_apic_timer_interrupt+0x1a/0x20 arch/x86/include/asm/idtentry.h:702 RIP: 0010:__orc_find arch/x86/kernel/unwind_orc.c:102 [inline] RIP: 0010:orc_find arch/x86/kernel/unwind_orc.c:227 [inline] RIP: 0010:unwind_next_frame+0x514/0x2a00 arch/x86/kernel/unwind_orc.c:494 Code: c1 e8 03 48 b9 00 00 00 00 00 fc ff df 0f b6 04 08 84 c0 75 34 48 63 2b 48 01 dd 48 89 ef 4c 89 f6 e8 f0 32 55 00 48 8d 43 04 <4c> 39 f5 4c 0f 46 e8 48 8d 43 fc 4c 0f 47 e0 4c 0f 46 fb 4d 39 e5 RSP: 0018:ffffc900000072a8 EFLAGS: 00000246 RAX: ffffffff8fbc8f04 RBX: ffffffff8fbc8f00 RCX: ffff888027b25a00 RDX: 0000000080000103 RSI: ffffffff81325ae5 RDI: ffffffff81325a58 RBP: ffffffff81325a58 R08: ffffffff8140f500 R09: ffffc90000007470 R10: 0000000000000003 R11: ffffffff8181de80 R12: ffffffff8fbc8f00 R13: ffffffff8fbc8f00 R14: ffffffff81325ae5 R15: ffffffff8fbc8efc arch_stack_walk+0x151/0x1b0 arch/x86/kernel/stacktrace.c:25 stack_trace_save+0x118/0x1d0 kernel/stacktrace.c:122 kasan_save_stack mm/kasan/common.c:47 [inline] kasan_save_track+0x3f/0x80 mm/kasan/common.c:68 unpoison_slab_object mm/kasan/common.c:312 [inline] __kasan_slab_alloc+0x66/0x80 mm/kasan/common.c:338 kasan_slab_alloc include/linux/kasan.h:201 [inline] slab_post_alloc_hook mm/slub.c:3941 [inline] slab_alloc_node mm/slub.c:4001 [inline] kmem_cache_alloc_node_noprof+0x16b/0x320 mm/slub.c:4044 __alloc_skb+0x1c3/0x440 net/core/skbuff.c:656 skb_copy+0x12b/0x820 net/core/skbuff.c:2124 mac80211_hwsim_tx_frame_no_nl+0x1068/0x18d0 drivers/net/wireless/virtual/mac80211_hwsim.c:1857 mac80211_hwsim_tx_frame+0x1cc/0x220 drivers/net/wireless/virtual/mac80211_hwsim.c:2206 mac80211_hwsim_beacon_tx+0x3bf/0x850 drivers/net/wireless/virtual/mac80211_hwsim.c:2306 __iterate_interfaces+0x225/0x4c0 net/mac80211/util.c:772 ieee80211_iterate_active_interfaces_atomic+0xd8/0x170 net/mac80211/util.c:808 mac80211_hwsim_beacon+0xd4/0x1f0 drivers/net/wireless/virtual/mac80211_hwsim.c:2336 __run_hrtimer kernel/time/hrtimer.c:1687 [inline] __hrtimer_run_queues+0x59d/0xd50 kernel/time/hrtimer.c:1751 hrtimer_run_softirq+0x19a/0x2c0 kernel/time/hrtimer.c:1768 handle_softirqs+0x2c6/0x970 kernel/softirq.c:554 __do_softirq kernel/softirq.c:588 [inline] invoke_softirq kernel/softirq.c:428 [inline] __irq_exit_rcu+0xf4/0x1c0 kernel/softirq.c:637 irq_exit_rcu+0x9/0x30 kernel/softirq.c:649 instr_sysvec_apic_timer_interrupt arch/x86/kernel/apic/apic.c:1043 [inline] sysvec_apic_timer_interrupt+0xa6/0xc0 arch/x86/kernel/apic/apic.c:1043 asm_sysvec_apic_timer_interrupt+0x1a/0x20 arch/x86/include/asm/idtentry.h:702 RIP: 0010:variable_test_bit arch/x86/include/asm/bitops.h:227 [inline] RIP: 0010:arch_test_bit arch/x86/include/asm/bitops.h:239 [inline] RIP: 0010:_test_bit include/asm-generic/bitops/instrumented-non-atomic.h:142 [inline] RIP: 0010:cpumask_test_cpu include/linux/cpumask.h:571 [inline] RIP: 0010:cpu_online include/linux/cpumask.h:1181 [inline] RIP: 0010:trace_lock_acquire include/trace/events/lock.h:24 [inline] RIP: 0010:lock_acquire+0xd4/0x550 kernel/locking/lockdep.c:5725 Code: 8b 05 1c 6f 91 7e 83 f8 08 0f 83 f4 02 00 00 89 c3 48 89 d8 48 c1 e8 06 48 8d 3c c5 28 4d ad 8f be 08 00 00 00 e8 1c 6f 89 00 <48> 0f a3 1d 4c e7 3a 0e 73 16 e8 6d ef 09 00 84 c0 75 0d 80 3d d0 RSP: 0018:ffffc90004bb7120 EFLAGS: 00000256 RAX: 0000000000000001 RBX: 0000000000000000 RCX: ffffffff817265d4 RDX: 0000000000000000 RSI: 0000000000000008 RDI: ffffffff8fad4d28 RBP: ffffc90004bb7278 R08: ffffffff8fad4d2f R09: 1ffffffff1f5a9a5 R10: dffffc0000000000 R11: fffffbfff1f5a9a6 R12: 1ffff92000976e2c R13: dffffc0000000000 R14: 0000000000000000 R15: ffffea00017eec00 rcu_lock_acquire include/linux/rcupdate.h:329 [inline] rcu_read_lock include/linux/rcupdate.h:781 [inline] page_ext_get+0x3d/0x2a0 mm/page_ext.c:521 page_table_check_clear+0x4b/0x550 mm/page_table_check.c:74 get_and_clear_full_ptes include/linux/pgtable.h:678 [inline] zap_present_folio_ptes mm/memory.c:1481 [inline] zap_present_ptes mm/memory.c:1564 [inline] zap_pte_range mm/memory.c:1606 [inline] zap_pmd_range mm/memory.c:1724 [inline] zap_pud_range mm/memory.c:1753 [inline] zap_p4d_range mm/memory.c:1774 [inline] unmap_page_range+0x2cd0/0x40f0 mm/memory.c:1795 unmap_vmas+0x3cc/0x5f0 mm/memory.c:1885 exit_mmap+0x264/0xc80 mm/mmap.c:3341 __mmput+0x115/0x3c0 kernel/fork.c:1346 exit_mm+0x220/0x310 kernel/exit.c:565 do_exit+0x9aa/0x27e0 kernel/exit.c:861 do_group_exit+0x207/0x2c0 kernel/exit.c:1023 get_signal+0x16a1/0x1740 kernel/signal.c:2909 arch_do_signal_or_restart+0x96/0x860 arch/x86/kernel/signal.c:310 exit_to_user_mode_loop kernel/entry/common.c:111 [inline] exit_to_user_mode_prepare include/linux/entry-common.h:328 [inline] irqentry_exit_to_user_mode+0x79/0x280 kernel/entry/common.c:231 exc_page_fault+0x590/0x8c0 arch/x86/mm/fault.c:1542 asm_exc_page_fault+0x26/0x30 arch/x86/include/asm/idtentry.h:623 RIP: 0033:0x7f1fb6c55bc6 Code: Unable to access opcode bytes at 0x7f1fb6c55b9c. RSP: 002b:00007ffd46f043e0 EFLAGS: 00010202 RAX: 0000000000019008 RBX: 00007f1fb7a35720 RCX: 0000000000000000 RDX: 0000001b2c507000 RSI: 0000000000000008 RDI: 00007f1fb7a35720 RBP: ffffffff81d271b0 R08: 00007f1fb6401050 R09: 0000000000000008 R10: 0000000081d28c1b R11: 0000000081d28c1f R12: 00000000000005da R13: 00007f1fb6f04038 R14: 0000000000000146 R15: fffffffffffe7000