syzbot

rcu: INFO: rcu_preempt detected stalls on CPUs/tasks:
rcu: 	0-...!: (1 GPs behind) idle=373/1/0x4000000000000002 softirq=17565/17567 fqs=0 
rcu: 	Tasks blocked on level-0 rcu_node (CPUs 0-1): P7868/2:b..l
	(detected by 1, t=10502 jiffies, g=23849, q=73)
Sending NMI from CPU 1 to CPUs 0:
NMI backtrace for cpu 0
CPU: 0 PID: 4234 Comm: kworker/0:5 Not tainted syzkaller #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 10/25/2025
Workqueue: events bpf_prog_free_deferred
RIP: 0010:memory_is_nonzero mm/kasan/generic.c:101 [inline]
RIP: 0010:memory_is_poisoned_n mm/kasan/generic.c:128 [inline]
RIP: 0010:memory_is_poisoned mm/kasan/generic.c:159 [inline]
RIP: 0010:check_region_inline mm/kasan/generic.c:180 [inline]
RIP: 0010:kasan_check_range+0x58/0x290 mm/kasan/generic.c:189
Code: 00 00 49 bf 01 00 00 00 00 fc ff df 49 89 fb 49 c1 eb 03 49 b8 00 00 00 00 00 fc ff df 4f 8d 0c 03 48 8d 5c 37 ff 48 c1 eb 03 <4e> 8d 14 3b 4d 89 d6 4d 29 ce 49 83 fe 10 7f 26 4d 85 f6 0f 84 39
RSP: 0018:ffffc9000423f580 EFLAGS: 00000803
RAX: 0000000000000001 RBX: 1ffffffff1ff5419 RCX: ffffffff815cb124
RDX: 0000000000000000 RSI: 0000000000000008 RDI: ffffffff8ffaa0c8
RBP: 0000000000000006 R08: dffffc0000000000 R09: fffffbfff1ff5419
R10: fffffbfff1ff5432 R11: 1ffffffff1ff5419 R12: 0000000000000040
R13: dffffc0000000000 R14: ffff8880239fe480 R15: dffffc0000000001
FS:  0000000000000000(0000) GS:ffff8880b9000000(0000) knlGS:0000000000000000
CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 00007ffcd61d8d78 CR3: 000000001afc1000 CR4: 00000000003506f0
DR0: 0000200000000380 DR1: 0000200000000380 DR2: 0000200000000380
DR3: 0000200000000380 DR6: 00000000ffff0ff0 DR7: 0000000000000600
Call Trace:
 <TASK>
 instrument_atomic_read include/linux/instrumented.h:71 [inline]
 test_bit include/asm-generic/bitops/instrumented-non-atomic.h:134 [inline]
 hlock_class kernel/locking/lockdep.c:197 [inline]
 mark_lock+0x94/0x320 kernel/locking/lockdep.c:4569
 mark_held_locks kernel/locking/lockdep.c:4193 [inline]
 __trace_hardirqs_on_caller kernel/locking/lockdep.c:4219 [inline]
 lockdep_hardirqs_on_prepare+0x365/0x760 kernel/locking/lockdep.c:4278
 trace_hardirqs_on+0x67/0x80 kernel/trace/trace_preemptirq.c:49
 asm_sysvec_irq_work+0x16/0x20 arch/x86/include/asm/idtentry.h:713
RIP: 0010:rcu_read_unlock_special+0x84/0x480 kernel/rcu/tree_plugin.h:674
Code: f1 f1 f1 00 f2 f2 f2 4a 89 04 2b 66 42 c7 44 2b 09 f3 f3 42 c6 44 2b 0b f3 65 44 8b 35 ed 11 9e 7e 41 f7 c6 00 00 f0 00 74 45 <48> c7 44 24 20 0e 36 e0 45 4a c7 04 2b 00 00 00 00 66 42 c7 44 2b
RSP: 0018:ffffc9000423f760 EFLAGS: 00000206
RAX: 592e0127dc191900 RBX: 1ffff92000847ef0 RCX: 592e0127dc191900
RDX: dffffc0000000000 RSI: ffffffff8a0b1be0 RDI: ffffffff8a59e800
RBP: ffffc9000423f838 R08: dffffc0000000000 R09: fffffbfff1ff5419
R10: fffffbfff1ff5419 R11: 1ffffffff1ff5418 R12: ffffffff8c120c00
R13: dffffc0000000000 R14: 0000000000000246 R15: 0000000000000001
 __rcu_read_unlock+0x78/0xd0 kernel/rcu/tree_plugin.h:422
 rcu_read_unlock include/linux/rcupdate.h:772 [inline]
 pfn_valid include/linux/mmzone.h:-1 [inline]
 __virt_addr_valid+0x3b8/0x470 arch/x86/mm/physaddr.c:65
 free_pages+0x12/0x50 mm/page_alloc.c:5573
 kasan_depopulate_vmalloc_pte+0x67/0x80 mm/kasan/shadow.c:375
 apply_to_pte_range mm/memory.c:2573 [inline]
 apply_to_pmd_range mm/memory.c:2617 [inline]
 apply_to_pud_range mm/memory.c:2653 [inline]
 apply_to_p4d_range mm/memory.c:2689 [inline]
 __apply_to_page_range+0x983/0xd10 mm/memory.c:2725
 kasan_release_vmalloc+0x93/0xb0 mm/kasan/shadow.c:485
 __purge_vmap_area_lazy+0xc6e/0x18f0 mm/vmalloc.c:1711
 _vm_unmap_aliases+0x410/0x4a0 mm/vmalloc.c:2114
 vm_remove_mappings mm/vmalloc.c:2591 [inline]
 __vunmap+0x70d/0xa40 mm/vmalloc.c:2618
 bpf_jit_binary_free kernel/bpf/core.c:918 [inline]
 bpf_jit_free+0x92/0x180 kernel/bpf/core.c:931
 process_one_work+0x863/0x1000 kernel/workqueue.c:2310
 worker_thread+0xaa8/0x12a0 kernel/workqueue.c:2457
 kthread+0x436/0x520 kernel/kthread.c:334
 ret_from_fork+0x1f/0x30 arch/x86/entry/entry_64.S:287
 </TASK>
task:syz.3.862       state:R  running task     stack:26688 pid: 7868 ppid:  4194 flags:0x00004000
Call Trace:
 <TASK>
 context_switch kernel/sched/core.c:5049 [inline]
 __schedule+0x11bb/0x4390 kernel/sched/core.c:6395
 preempt_schedule_irq+0xb1/0x150 kernel/sched/core.c:6799
 irqentry_exit+0x63/0x70 kernel/entry/common.c:432
 asm_sysvec_apic_timer_interrupt+0x16/0x20 arch/x86/include/asm/idtentry.h:676
RIP: 0010:check_region_inline mm/kasan/generic.c:169 [inline]
RIP: 0010:kasan_check_range+0xf/0x290 mm/kasan/generic.c:189
Code: 0b b8 ea ff ff ff c3 0f 0b b8 ea ff ff ff c3 00 00 cc cc 00 00 cc cc 00 00 cc cc b0 01 48 85 f6 0f 84 a4 01 00 00 41 57 41 56 <53> 49 89 f8 49 01 f0 0f 82 57 02 00 00 49 89 f8 49 c1 e8 2f 41 81
RSP: 0018:ffffc900034afb88 EFLAGS: 00000202
RAX: 0000000000000001 RBX: 0000000000000000 RCX: ffffffff815bfaab
RDX: 0000000000000000 RSI: 0000000000000008 RDI: ffffffff8d6935a8
RBP: ffffc900034afcb8 R08: 0000000000000000 R09: 0000000000000000
R10: fffffbfff1ff5419 R11: 1ffffffff1ff5418 R12: ffffffff8c11c720
R13: 1ffff92000695f80 R14: 0000000000000001 R15: dffffc0000000000
 instrument_atomic_read include/linux/instrumented.h:71 [inline]
 test_bit include/asm-generic/bitops/instrumented-non-atomic.h:134 [inline]
 cpumask_test_cpu include/linux/cpumask.h:344 [inline]
 cpu_online include/linux/cpumask.h:895 [inline]
 trace_lock_acquire include/trace/events/lock.h:13 [inline]
 lock_acquire+0xbb/0x3f0 kernel/locking/lockdep.c:5594
 rcu_lock_acquire+0x2a/0x30 include/linux/rcupdate.h:313
 rcu_read_lock include/linux/rcupdate.h:740 [inline]
 percpu_ref_tryget_many include/linux/percpu-refcount.h:241 [inline]
 percpu_ref_tryget include/linux/percpu-refcount.h:266 [inline]
 css_tryget include/linux/cgroup.h:355 [inline]
 cgroup_tryget+0x52/0x270 include/linux/cgroup.h:428
 cgroup_sk_alloc+0x223/0x380 kernel/cgroup/cgroup.c:6771
 sk_alloc+0x20b/0x310 net/core/sock.c:1942
 unix_create1+0xb0/0x610 net/unix/af_unix.c:-1
 unix_create+0x143/0x1f0 net/unix/af_unix.c:929
 __sock_create+0x47b/0x900 net/socket.c:1496
 sock_create net/socket.c:1552 [inline]
 __sys_socketpair+0x232/0x540 net/socket.c:1656
 __do_sys_socketpair net/socket.c:1705 [inline]
 __se_sys_socketpair net/socket.c:1702 [inline]
 __x64_sys_socketpair+0x97/0xb0 net/socket.c:1702
 do_syscall_x64 arch/x86/entry/common.c:50 [inline]
 do_syscall_64+0x4c/0xa0 arch/x86/entry/common.c:80
 entry_SYSCALL_64_after_hwframe+0x66/0xd0
RIP: 0033:0x7f741b33d749
RSP: 002b:00007f74195a4038 EFLAGS: 00000246 ORIG_RAX: 0000000000000035
RAX: ffffffffffffffda RBX: 00007f741b593fa0 RCX: 00007f741b33d749
RDX: 0000000000000000 RSI: 0000000000000001 RDI: 0000000000000001
RBP: 00007f741b3c1f91 R08: 0000000000000000 R09: 0000000000000000
R10: 0000200000000000 R11: 0000000000000246 R12: 0000000000000000
R13: 00007f741b594038 R14: 00007f741b593fa0 R15: 00007fff1c767c28
 </TASK>
rcu: rcu_preempt kthread starved for 10502 jiffies! g23849 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:27688 pid:   15 ppid:     2 flags:0x00004000
Call Trace:
 <TASK>
 context_switch kernel/sched/core.c:5049 [inline]
 __schedule+0x11bb/0x4390 kernel/sched/core.c:6395
 schedule+0x11b/0x1e0 kernel/sched/core.c:6478
 schedule_timeout+0x15c/0x280 kernel/time/timer.c:1914
 rcu_gp_fqs_loop+0x29e/0x11b0 kernel/rcu/tree.c:1972
 rcu_gp_kthread+0x98/0x350 kernel/rcu/tree.c:2145
 kthread+0x436/0x520 kernel/kthread.c:334
 ret_from_fork+0x1f/0x30 arch/x86/entry/entry_64.S:287
 </TASK>
rcu: Stack dump where RCU GP kthread last ran:
NMI backtrace for cpu 1
CPU: 1 PID: 7877 Comm: syz.0.865 Not tainted syzkaller #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 10/25/2025
Call Trace:
 <IRQ>
 dump_stack_lvl+0x168/0x230 lib/dump_stack.c:106
 nmi_cpu_backtrace+0x397/0x3d0 lib/nmi_backtrace.c:111
 nmi_trigger_cpumask_backtrace+0x163/0x280 lib/nmi_backtrace.c:62
 trigger_single_cpu_backtrace include/linux/nmi.h:166 [inline]
 rcu_check_gp_kthread_starvation+0x1cd/0x250 kernel/rcu/tree_stall.h:487
 print_other_cpu_stall+0x10c8/0x1220 kernel/rcu/tree_stall.h:592
 check_cpu_stall kernel/rcu/tree_stall.h:745 [inline]
 rcu_pending kernel/rcu/tree.c:3936 [inline]
 rcu_sched_clock_irq+0x831/0x1110 kernel/rcu/tree.c:2619
 update_process_times+0x193/0x200 kernel/time/timer.c:1818
 tick_sched_handle kernel/time/tick-sched.c:254 [inline]
 tick_sched_timer+0x37d/0x560 kernel/time/tick-sched.c:1473
 __run_hrtimer kernel/time/hrtimer.c:1685 [inline]
 __hrtimer_run_queues+0x4fe/0xc40 kernel/time/hrtimer.c:1749
 hrtimer_interrupt+0x3bb/0x8d0 kernel/time/hrtimer.c:1811
 local_apic_timer_interrupt arch/x86/kernel/apic/apic.c:1097 [inline]
 __sysvec_apic_timer_interrupt+0x137/0x4a0 arch/x86/kernel/apic/apic.c:1114
 instr_sysvec_apic_timer_interrupt arch/x86/kernel/apic/apic.c:1108 [inline]
 sysvec_apic_timer_interrupt+0x9b/0xc0 arch/x86/kernel/apic/apic.c:1108
 </IRQ>
 <TASK>
 asm_sysvec_apic_timer_interrupt+0x16/0x20 arch/x86/include/asm/idtentry.h:676
RIP: 0010:native_safe_halt arch/x86/include/asm/irqflags.h:51 [inline]
RIP: 0010:arch_safe_halt arch/x86/include/asm/irqflags.h:89 [inline]
RIP: 0010:kvm_wait+0x141/0x190 arch/x86/kernel/kvm.c:918
Code: 89 df 48 89 f8 48 c1 e8 03 42 0f b6 04 30 84 c0 75 47 0f b6 1f e8 1f e2 49 00 44 38 e3 75 10 66 90 0f 00 2d c1 68 d4 08 fb f4 <e9> 33 ff ff ff fb e9 2d ff ff ff e8 4f df 6d 08 89 f9 80 e1 07 38
RSP: 0018:ffffc90002fef480 EFLAGS: 00000246
RAX: c6d1522cd76e1c00 RBX: 0000000000000003 RCX: c6d1522cd76e1c00
RDX: dffffc0000000000 RSI: ffffffff8a0b1be0 RDI: ffffffff8a59e800
RBP: ffffc90002fef530 R08: dffffc0000000000 R09: fffffbfff1ff5419
R10: fffffbfff1ff5419 R11: 1ffffffff1ff5418 R12: 0000000000000003
R13: ffff8880b913b154 R14: dffffc0000000000 R15: 1ffff920005fde90
 pv_wait arch/x86/include/asm/paravirt.h:597 [inline]
 pv_wait_head_or_lock kernel/locking/qspinlock_paravirt.h:470 [inline]
 __pv_queued_spin_lock_slowpath+0x60f/0x9c0 kernel/locking/qspinlock.c:508
 pv_queued_spin_lock_slowpath arch/x86/include/asm/paravirt.h:585 [inline]
 queued_spin_lock_slowpath+0x43/0x50 arch/x86/include/asm/qspinlock.h:51
 queued_spin_lock include/asm-generic/qspinlock.h:85 [inline]
 do_raw_spin_lock+0x217/0x280 kernel/locking/spinlock_debug.c:115
 spin_lock include/linux/spinlock.h:364 [inline]
 preload_this_cpu_lock mm/vmalloc.c:1507 [inline]
 alloc_vmap_area+0x228/0x1b20 mm/vmalloc.c:1549
 __get_vm_area_node+0x14f/0x2d0 mm/vmalloc.c:2430
 __vmalloc_node_range+0xef/0x8b0 mm/vmalloc.c:3027
 alloc_thread_stack_node kernel/fork.c:246 [inline]
 dup_task_struct+0x3f5/0xb30 kernel/fork.c:899
 copy_process+0x5b3/0x3e00 kernel/fork.c:2121
 kernel_clone+0x219/0x930 kernel/fork.c:2679
 __do_sys_clone3 kernel/fork.c:2954 [inline]
 __se_sys_clone3+0x2d5/0x360 kernel/fork.c:2938
 do_syscall_x64 arch/x86/entry/common.c:50 [inline]
 do_syscall_64+0x4c/0xa0 arch/x86/entry/common.c:80
 entry_SYSCALL_64_after_hwframe+0x66/0xd0
RIP: 0033:0x7f43618cee89
Code: ef 08 00 48 8d 3d 5c ef 08 00 e8 12 29 f6 ff 66 90 b8 ea ff ff ff 48 85 ff 74 2c 48 85 d2 74 27 49 89 c8 b8 b3 01 00 00 0f 05 <48> 85 c0 7c 18 74 01 c3 31 ed 48 83 e4 f0 4c 89 c7 ff d2 48 89 c7
RSP: 002b:00007fffe31e9778 EFLAGS: 00000206 ORIG_RAX: 00000000000001b3
RAX: ffffffffffffffda RBX: 00007f43618512a0 RCX: 00007f43618cee89
RDX: 00007f43618512a0 RSI: 0000000000000058 RDI: 00007fffe31e97c0
RBP: 00007f435fabf6c0 R08: 00007f435fabf6c0 R09: 00007fffe31e98a7
R10: 0000000000000008 R11: 0000000000000206 R12: ffffffffffffffa8
R13: 000000000000000b R14: 00007fffe31e97c0 R15: 00007fffe31e98a8
 </TASK>