rcu: INFO: rcu_preempt self-detected stall on CPU rcu: 0-...!: (10489 ticks this GP) idle=cc6/1/0x4000000000000000 softirq=229433/229443 fqs=0 (t=10501 jiffies g=413857 q=34) rcu: rcu_preempt kthread starved for 10502 jiffies! g413857 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:29088 pid: 10 ppid: 2 flags:0x00004000 Call Trace: context_switch kernel/sched/core.c:3778 [inline] __schedule+0x8fc/0x2240 kernel/sched/core.c:4527 schedule+0xd0/0x2a0 kernel/sched/core.c:4602 schedule_timeout+0x148/0x250 kernel/time/timer.c:1879 rcu_gp_fqs_loop kernel/rcu/tree.c:1888 [inline] rcu_gp_kthread+0xb2c/0x1ca0 kernel/rcu/tree.c:2058 kthread+0x3b5/0x4a0 kernel/kthread.c:292 ret_from_fork+0x1f/0x30 arch/x86/entry/entry_64.S:294 NMI backtrace for cpu 0 CPU: 0 PID: 13553 Comm: syz-executor.0 Not tainted 5.9.0-rc1-syzkaller #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011 Call Trace: __dump_stack lib/dump_stack.c:77 [inline] dump_stack+0x18f/0x20d lib/dump_stack.c:118 nmi_cpu_backtrace.cold+0x70/0xb1 lib/nmi_backtrace.c:101 nmi_trigger_cpumask_backtrace+0x1b3/0x223 lib/nmi_backtrace.c:62 trigger_single_cpu_backtrace include/linux/nmi.h:164 [inline] rcu_dump_cpu_stacks+0x1e3/0x21e kernel/rcu/tree_stall.h:318 print_cpu_stall kernel/rcu/tree_stall.h:551 [inline] check_cpu_stall kernel/rcu/tree_stall.h:625 [inline] rcu_pending kernel/rcu/tree.c:3637 [inline] rcu_sched_clock_irq.cold+0x4db/0xdfd kernel/rcu/tree.c:2519 update_process_times+0x25/0xa0 kernel/time/timer.c:1710 tick_sched_handle+0x9b/0x180 kernel/time/tick-sched.c:176 tick_sched_timer+0x1d1/0x2a0 kernel/time/tick-sched.c:1328 __run_hrtimer kernel/time/hrtimer.c:1524 [inline] __hrtimer_run_queues+0x1d5/0xfc0 kernel/time/hrtimer.c:1588 hrtimer_interrupt+0x334/0x940 kernel/time/hrtimer.c:1650 local_apic_timer_interrupt arch/x86/kernel/apic/apic.c:1080 [inline] __sysvec_apic_timer_interrupt+0x147/0x5f0 arch/x86/kernel/apic/apic.c:1097 run_on_irqstack_cond arch/x86/include/asm/irq_stack.h:50 [inline] sysvec_apic_timer_interrupt+0x4c/0xf0 arch/x86/kernel/apic/apic.c:1091 asm_sysvec_apic_timer_interrupt+0x12/0x20 arch/x86/include/asm/idtentry.h:581 RIP: 0010:mac80211_hwsim_tx_frame_no_nl.isra.0+0x72c/0x12d0 drivers/net/wireless/mac80211_hwsim.c:1408 Code: 00 00 00 c6 84 24 98 00 00 00 00 74 bb e8 dc 30 52 fc 48 8d bb c4 19 00 00 48 89 f8 48 89 fa 48 c1 e8 03 83 e2 07 0f b6 04 28 <38> d0 7f 08 84 c0 0f 85 39 09 00 00 44 0f b6 bb c4 19 00 00 31 ff RSP: 0018:ffffc90000007b68 EFLAGS: 00000202 RAX: 0000000000000000 RBX: ffff888087b93120 RCX: ffffffff8524471a RDX: 0000000000000004 RSI: ffffffff852446e4 RDI: ffff888087b94ae4 RBP: dffffc0000000000 R08: 0000000000000001 R09: 0000000000000003 R10: 0000000000000000 R11: 0000000000000000 R12: ffff88803a29fb40 R13: ffff888050203120 R14: ffff888050203350 R15: 0000000000000000 mac80211_hwsim_tx_frame+0x14f/0x1e0 drivers/net/wireless/mac80211_hwsim.c:1654 mac80211_hwsim_beacon_tx+0x439/0x810 drivers/net/wireless/mac80211_hwsim.c:1694 __iterate_interfaces+0x124/0x4d0 net/mac80211/util.c:737 ieee80211_iterate_active_interfaces_atomic+0x8d/0x170 net/mac80211/util.c:773 mac80211_hwsim_beacon+0xd5/0x1a0 drivers/net/wireless/mac80211_hwsim.c:1717 __run_hrtimer kernel/time/hrtimer.c:1524 [inline] __hrtimer_run_queues+0x6a9/0xfc0 kernel/time/hrtimer.c:1588 hrtimer_run_softirq+0x17b/0x360 kernel/time/hrtimer.c:1605 __do_softirq+0x2ed/0xab4 kernel/softirq.c:298 asm_call_on_stack+0xf/0x20 arch/x86/entry/entry_64.S:706 __run_on_irqstack arch/x86/include/asm/irq_stack.h:22 [inline] run_on_irqstack_cond arch/x86/include/asm/irq_stack.h:48 [inline] do_softirq_own_stack+0x9d/0xd0 arch/x86/kernel/irq_64.c:77 invoke_softirq kernel/softirq.c:393 [inline] __irq_exit_rcu kernel/softirq.c:423 [inline] irq_exit_rcu+0x1f3/0x230 kernel/softirq.c:435 sysvec_apic_timer_interrupt+0x51/0xf0 arch/x86/kernel/apic/apic.c:1091 asm_sysvec_apic_timer_interrupt+0x12/0x20 arch/x86/include/asm/idtentry.h:581 RIP: 0010:__orc_find+0xa8/0xf0 arch/x86/kernel/unwind_orc.c:59 Code: 75 48 48 63 03 48 01 d8 48 39 c1 73 b0 4c 8d 63 fc 49 39 ec 73 b3 4d 29 ee 49 c1 fe 02 4b 8d 04 76 48 8d 04 46 48 83 c4 10 5b <5d> 41 5c 41 5d 41 5e 41 5f c3 48 83 c4 10 31 c0 5b 5d 41 5c 41 5d RSP: 0018:ffffc90007447328 EFLAGS: 00000282 RAX: ffffffff8bd0ecbc RBX: 1ffff92000e88e73 RCX: ffffffff81c7a267 RDX: 0000000000000000 RSI: ffffffff8bd0ec92 RDI: ffffffff8b6e6e00 RBP: ffffffff8b6e6e20 R08: ffffffff8bd0ecc2 R09: ffffffff8bd0ec92 R10: 000000000007601e R11: 000000000002d7e1 R12: ffffffff8b6e6e1c R13: ffffffff8b6e6e00 R14: 0000000000000007 R15: dffffc0000000000 orc_find arch/x86/kernel/unwind_orc.c:172 [inline] unwind_next_frame+0x342/0x1f90 arch/x86/kernel/unwind_orc.c:449 arch_stack_walk+0x81/0xf0 arch/x86/kernel/stacktrace.c:25 stack_trace_save+0x8c/0xc0 kernel/stacktrace.c:123 kasan_save_stack+0x1b/0x40 mm/kasan/common.c:48 kasan_set_track mm/kasan/common.c:56 [inline] __kasan_kmalloc.constprop.0+0xbf/0xd0 mm/kasan/common.c:461 slab_post_alloc_hook mm/slab.h:518 [inline] slab_alloc mm/slab.c:3312 [inline] kmem_cache_alloc+0x138/0x3e0 mm/slab.c:3482 ext4_es_alloc_extent fs/ext4/extents_status.c:449 [inline] __es_insert_extent+0x39b/0x13b0 fs/ext4/extents_status.c:788 __es_remove_extent+0x4ac/0x15d0 fs/ext4/extents_status.c:1335 ext4_es_remove_extent+0x13f/0x420 fs/ext4/extents_status.c:1438 ext4_punch_hole+0xeb2/0x1180 fs/ext4/inode.c:4060 ext4_fallocate+0x1089/0x3f20 fs/ext4/extents.c:4653 vfs_fallocate+0x48d/0x9d0 fs/open.c:309 ioctl_preallocate+0x18e/0x200 fs/ioctl.c:494 file_ioctl fs/ioctl.c:537 [inline] do_vfs_ioctl+0xde1/0x1090 fs/ioctl.c:732 __do_sys_ioctl fs/ioctl.c:751 [inline] __se_sys_ioctl fs/ioctl.c:739 [inline] __x64_sys_ioctl+0x108/0x200 fs/ioctl.c:739 do_syscall_64+0x2d/0x70 arch/x86/entry/common.c:46 entry_SYSCALL_64_after_hwframe+0x44/0xa9 RIP: 0033:0x45e179 Code: 3d b2 fb ff c3 66 2e 0f 1f 84 00 00 00 00 00 66 90 48 89 f8 48 89 f7 48 89 d6 48 89 ca 4d 89 c2 4d 89 c8 4c 8b 4c 24 08 0f 05 <48> 3d 01 f0 ff ff 0f 83 0b b2 fb ff c3 66 2e 0f 1f 84 00 00 00 00 RSP: 002b:00007fa888df4c78 EFLAGS: 00000246 ORIG_RAX: 0000000000000010 RAX: ffffffffffffffda RBX: 0000000000012e40 RCX: 000000000045e179 RDX: 0000000020000040 RSI: 0000000040305829 RDI: 0000000000000004 RBP: 000000000118d028 R08: 0000000000000000 R09: 0000000000000000 R10: 0000000000000000 R11: 0000000000000246 R12: 000000000118cff4 R13: 00007ffca2c8462f R14: 00007fa888df59c0 R15: 000000000118cff4