rcu: INFO: rcu_preempt detected stalls on CPUs/tasks: rcu: Tasks blocked on level-0 rcu_node (CPUs 0-1): P29545/1:b..l (detected by 1, t=10502 jiffies, g=282209, q=8) task:syz-executor.5 state:R running task stack:29248 pid:29546 ppid: 8564 flags:0x00004000 Call Trace: context_switch kernel/sched/core.c:4322 [inline] __schedule+0x911/0x21b0 kernel/sched/core.c:5073 preempt_schedule_irq+0x4e/0x90 kernel/sched/core.c:5530 irqentry_exit_cond_resched kernel/entry/common.c:392 [inline] irqentry_exit_cond_resched kernel/entry/common.c:384 [inline] irqentry_exit+0x7a/0xa0 kernel/entry/common.c:428 asm_sysvec_apic_timer_interrupt+0x12/0x20 arch/x86/include/asm/idtentry.h:632 RIP: 0010:lock_acquire+0x1ef/0x740 kernel/locking/lockdep.c:5478 Code: 4b a8 7e 83 f8 01 0f 85 ee 03 00 00 9c 58 f6 c4 02 0f 85 d9 03 00 00 48 83 7c 24 08 00 74 01 fb 48 b8 00 00 00 00 00 fc ff df <48> 01 c3 48 c7 03 00 00 00 00 48 c7 43 08 00 00 00 00 48 8b 84 24 RSP: 0018:ffffc9001164f9a0 EFLAGS: 00000206 RAX: dffffc0000000000 RBX: 1ffff920022c9f36 RCX: 0000000008ef54f4 RDX: 1ffff110056eebd5 RSI: 0000000000000000 RDI: 0000000000000000 RBP: 0000000000000000 R08: 0000000000000000 R09: ffffffff8fad58a7 R10: fffffbfff1f5ab14 R11: 0000000000000000 R12: 0000000000000002 R13: ffffffff8bf74360 R14: 0000000000000000 R15: 0000000000000000 rcu_lock_acquire include/linux/rcupdate.h:267 [inline] rcu_read_lock include/linux/rcupdate.h:656 [inline] ext4_get_group_desc+0x146/0x510 fs/ext4/balloc.c:284 recently_deleted fs/ext4/ialloc.c:682 [inline] find_inode_bit+0x1b8/0x570 fs/ext4/ialloc.c:728 __ext4_new_inode+0xc4d/0x5570 fs/ext4/ialloc.c:1063 ext4_symlink+0x489/0xd50 fs/ext4/namei.c:3347 vfs_symlink fs/namei.c:4176 [inline] vfs_symlink+0x10f/0x270 fs/namei.c:4161 do_symlinkat+0x27a/0x300 fs/namei.c:4206 do_syscall_64+0x2d/0x70 arch/x86/entry/common.c:46 entry_SYSCALL_64_after_hwframe+0x44/0xae RIP: 0033:0x465f07 RSP: 002b:00007ffc1b464228 EFLAGS: 00000206 ORIG_RAX: 0000000000000058 RAX: ffffffffffffffda RBX: 0000000000000000 RCX: 0000000000465f07 RDX: 00007ffc1b464313 RSI: 00000000004bfc70 RDI: 00007ffc1b464300 RBP: 0000000000000000 R08: 0000000000000000 R09: 00007ffc1b4640c0 R10: 00007ffc1b463f77 R11: 0000000000000206 R12: 0000000000000001 R13: 0000000000000000 R14: 0000000000000001 R15: 00007ffc1b464300 task:syz-executor.3 state:R running task stack:29248 pid:29545 ppid: 19250 flags:0x00004000 Call Trace: context_switch kernel/sched/core.c:4322 [inline] __schedule+0x911/0x21b0 kernel/sched/core.c:5073 preempt_schedule_irq+0x4e/0x90 kernel/sched/core.c:5530 irqentry_exit_cond_resched kernel/entry/common.c:392 [inline] irqentry_exit_cond_resched kernel/entry/common.c:384 [inline] irqentry_exit+0x7a/0xa0 kernel/entry/common.c:428 asm_sysvec_apic_timer_interrupt+0x12/0x20 arch/x86/include/asm/idtentry.h:632 RIP: 0010:lock_is_held_type+0xfd/0x140 kernel/locking/lockdep.c:5554 Code: 00 00 b8 ff ff ff ff 65 0f c1 05 7e 55 fc 76 83 f8 01 75 29 9c 58 f6 c4 02 75 3d 48 f7 04 24 00 02 00 00 74 01 fb 48 83 c4 08 <44> 89 e8 5b 5d 41 5c 41 5d 41 5e 41 5f c3 45 31 ed eb b9 0f 0b 48 RSP: 0018:ffffc9001163fa58 EFLAGS: 00000282 RAX: 0000000000000046 RBX: 0000000000000002 RCX: 0000000000000001 RDX: 0000000000000000 RSI: 0000000000000000 RDI: 0000000000000000 RBP: ffffffff8bf74360 R08: 0000000000000001 R09: 0000000000000000 R10: ffffffff820229f6 R11: 0000000000000000 R12: ffff88805d7b9c40 R13: 0000000000000001 R14: 00000000ffffffff R15: ffff88805d7ba680 ext4_get_group_desc+0x36c/0x510 fs/ext4/balloc.c:284 recently_deleted fs/ext4/ialloc.c:682 [inline] find_inode_bit+0x1b8/0x570 fs/ext4/ialloc.c:728 __ext4_new_inode+0xc4d/0x5570 fs/ext4/ialloc.c:1063 ext4_symlink+0x489/0xd50 fs/ext4/namei.c:3347 vfs_symlink fs/namei.c:4176 [inline] vfs_symlink+0x10f/0x270 fs/namei.c:4161 do_symlinkat+0x27a/0x300 fs/namei.c:4206 do_syscall_64+0x2d/0x70 arch/x86/entry/common.c:46 entry_SYSCALL_64_after_hwframe+0x44/0xae RIP: 0033:0x465f07 RSP: 002b:00007ffec5a781a8 EFLAGS: 00000202 ORIG_RAX: 0000000000000058 RAX: ffffffffffffffda RBX: 0000000000000000 RCX: 0000000000465f07 RDX: 00007ffec5a78293 RSI: 00000000004bfc70 RDI: 00007ffec5a78280 RBP: 0000000000000000 R08: 0000000000000000 R09: 00007ffec5a78040 R10: 00007ffec5a77ef7 R11: 0000000000000202 R12: 0000000000000001 R13: 0000000000000000 R14: 0000000000000001 R15: 00007ffec5a78280 rcu: rcu_preempt kthread timer wakeup didn't happen for 10501 jiffies! g282209 f0x0 RCU_GP_WAIT_FQS(5) ->state=0x402 rcu: Possible timer handling issue on cpu=1 timer-softirq=138699 rcu: rcu_preempt kthread starved for 10502 jiffies! g282209 f0x0 RCU_GP_WAIT_FQS(5) ->state=0x402 ->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:I stack:29112 pid: 14 ppid: 2 flags:0x00004000 Call Trace: context_switch kernel/sched/core.c:4322 [inline] __schedule+0x911/0x21b0 kernel/sched/core.c:5073 schedule+0xcf/0x270 kernel/sched/core.c:5152 schedule_timeout+0x14a/0x250 kernel/time/timer.c:1892 rcu_gp_fqs_loop kernel/rcu/tree.c:2005 [inline] rcu_gp_kthread+0xd07/0x2250 kernel/rcu/tree.c:2178 kthread+0x3b1/0x4a0 kernel/kthread.c:292 ret_from_fork+0x1f/0x30 arch/x86/entry/entry_64.S:294 rcu: Stack dump where RCU GP kthread last ran: NMI backtrace for cpu 1 CPU: 1 PID: 29550 Comm: syz-executor.4 Not tainted 5.12.0-rc4-syzkaller #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011 Call Trace: __dump_stack lib/dump_stack.c:79 [inline] dump_stack+0x141/0x1d7 lib/dump_stack.c:120 nmi_cpu_backtrace.cold+0x44/0xd7 lib/nmi_backtrace.c:105 nmi_trigger_cpumask_backtrace+0x1b3/0x230 lib/nmi_backtrace.c:62 trigger_single_cpu_backtrace include/linux/nmi.h:164 [inline] rcu_check_gp_kthread_starvation+0x1c7/0x1e4 kernel/rcu/tree_stall.h:478 print_other_cpu_stall kernel/rcu/tree_stall.h:582 [inline] check_cpu_stall kernel/rcu/tree_stall.h:706 [inline] rcu_pending kernel/rcu/tree.c:3830 [inline] rcu_sched_clock_irq.cold+0x9a3/0x11dd kernel/rcu/tree.c:2650 update_process_times+0x16d/0x200 kernel/time/timer.c:1796 tick_sched_handle+0x9b/0x180 kernel/time/tick-sched.c:226 tick_sched_timer+0x1b0/0x2d0 kernel/time/tick-sched.c:1369 __run_hrtimer kernel/time/hrtimer.c:1537 [inline] __hrtimer_run_queues+0x1c0/0xe40 kernel/time/hrtimer.c:1601 hrtimer_interrupt+0x330/0xa00 kernel/time/hrtimer.c:1663 local_apic_timer_interrupt arch/x86/kernel/apic/apic.c:1089 [inline] __sysvec_apic_timer_interrupt+0x146/0x540 arch/x86/kernel/apic/apic.c:1106 sysvec_apic_timer_interrupt+0x8e/0xc0 arch/x86/kernel/apic/apic.c:1100 asm_sysvec_apic_timer_interrupt+0x12/0x20 arch/x86/include/asm/idtentry.h:632 RIP: 0010:pv_wait_head_or_lock kernel/locking/qspinlock_paravirt.h:434 [inline] RIP: 0010:__pv_queued_spin_lock_slowpath+0x3ba/0xb40 kernel/locking/qspinlock.c:508 Code: eb c6 45 01 01 41 bc 00 80 00 00 48 c1 e9 03 83 e3 07 41 be 01 00 00 00 48 b8 00 00 00 00 00 fc ff df 4c 8d 2c 01 eb 0c f3 90 <41> 83 ec 01 0f 84 72 04 00 00 41 0f b6 45 00 38 d8 7f 08 84 c0 0f RSP: 0018:ffffc900116ef528 EFLAGS: 00000206 RAX: 0000000000000003 RBX: 0000000000000000 RCX: 1ffffffff18118d0 RDX: 0000000000000001 RSI: ffffffff8179e5d1 RDI: ffffffff813214c1 RBP: ffffffff8c08c680 R08: 0000000000000001 R09: 0000000000000001 R10: ffffffff8179e599 R11: 0000000000000000 R12: 0000000000005bde R13: fffffbfff18118d0 R14: 0000000000000001 R15: ffff8880b9d35f40 pv_queued_spin_lock_slowpath arch/x86/include/asm/paravirt.h:554 [inline] queued_spin_lock_slowpath arch/x86/include/asm/qspinlock.h:51 [inline] queued_spin_lock include/asm-generic/qspinlock.h:85 [inline] do_raw_spin_lock+0x200/0x2b0 kernel/locking/spinlock_debug.c:113 spin_lock include/linux/spinlock.h:354 [inline] alloc_vmap_area+0x1ba/0x1e10 mm/vmalloc.c:1215 __get_vm_area_node+0x128/0x380 mm/vmalloc.c:2096 __vmalloc_node_range mm/vmalloc.c:2571 [inline] __vmalloc_node mm/vmalloc.c:2619 [inline] vmalloc+0xf2/0x1a0 mm/vmalloc.c:2652 bpf_prog_calc_tag+0xc0/0x740 kernel/bpf/core.c:276 resolve_pseudo_ldimm64 kernel/bpf/verifier.c:11089 [inline] bpf_check+0x36e0/0xcd10 kernel/bpf/verifier.c:13302 bpf_prog_load+0xe47/0x1f40 kernel/bpf/syscall.c:2216 __do_sys_bpf+0x1272/0x4f40 kernel/bpf/syscall.c:4399 do_syscall_64+0x2d/0x70 arch/x86/entry/common.c:46 entry_SYSCALL_64_after_hwframe+0x44/0xae RIP: 0033:0x4665f9 Code: ff ff c3 66 2e 0f 1f 84 00 00 00 00 00 0f 1f 40 00 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 73 01 c3 48 c7 c1 bc ff ff ff f7 d8 64 89 01 48 RSP: 002b:00007f37896c6188 EFLAGS: 00000246 ORIG_RAX: 0000000000000141 RAX: ffffffffffffffda RBX: 000000000056bf60 RCX: 00000000004665f9 RDX: 000000000000004a RSI: 0000000020000200 RDI: 0000000000000005 RBP: 00000000004bfbb9 R08: 0000000000000000 R09: 0000000000000000 R10: 0000000000000000 R11: 0000000000000246 R12: 000000000056bf60 R13: 00007ffe3d8f1e6f R14: 00007f37896c6300 R15: 0000000000022000