rcu: INFO: rcu_preempt detected stalls on CPUs/tasks:
rcu: Tasks blocked on level-0 rcu_node (CPUs 0-1): P6528/1:b..l
rcu: (detected by 0, t=10503 jiffies, g=15157, q=716 ncpus=2)
task:cmp state:R running task stack:25736 pid:6528 tgid:6528 ppid:6500 task_flags:0x400000 flags:0x00080000
Call Trace:
context_switch kernel/sched/core.c:5260 [inline]
__schedule+0xfe6/0x5fa0 kernel/sched/core.c:6867
preempt_schedule_irq+0x50/0x90 kernel/sched/core.c:7194
irqentry_exit+0x17b/0x670 kernel/entry/common.c:216
asm_sysvec_apic_timer_interrupt+0x1a/0x20 arch/x86/include/asm/idtentry.h:697
RIP: 0010:lock_acquire+0x5e/0x330 kernel/locking/lockdep.c:5872
Code: 05 bb 52 01 12 83 f8 07 0f 87 a4 02 00 00 48 0f a3 05 46 31 d4 0e 0f 82 6f 02 00 00 8b 35 3e 64 d4 0e 85 f6 0f 85 8a 00 00 00 <48> 8b 44 24 30 65 48 2b 05 5d 52 01 12 0f 85 b8 02 00 00 48 83 c4
RSP: 0018:ffffc90003fcee80 EFLAGS: 00000206
RAX: 0000000000000046 RBX: 0000000000000000 RCX: 0000000000000001
RDX: 0000000000000000 RSI: ffffffff8dc20053 RDI: ffffffff8bfa38a0
RBP: ffffffff8e5e32e0 R08: 00000000a1bbbf67 R09: 0000000000000007
R10: 0000000000000200 R11: 0000000000000000 R12: 0000000000000002
R13: 0000000000000000 R14: 0000000000000000 R15: 0000000000000000
rcu_lock_acquire include/linux/rcupdate.h:331 [inline]
rcu_read_lock include/linux/rcupdate.h:867 [inline]
class_rcu_constructor include/linux/rcupdate.h:1195 [inline]
unwind_next_frame+0xd1/0x1ea0 arch/x86/kernel/unwind_orc.c:495
arch_stack_walk+0x94/0xf0 arch/x86/kernel/stacktrace.c:25
stack_trace_save+0x8e/0xc0 kernel/stacktrace.c:122
kasan_save_stack+0x30/0x50 mm/kasan/common.c:57
kasan_save_track+0x14/0x30 mm/kasan/common.c:78
unpoison_slab_object mm/kasan/common.c:340 [inline]
__kasan_slab_alloc+0x89/0x90 mm/kasan/common.c:366
kasan_slab_alloc include/linux/kasan.h:253 [inline]
slab_post_alloc_hook mm/slub.c:4953 [inline]
slab_alloc_node mm/slub.c:5263 [inline]
kmem_cache_alloc_noprof+0x2ad/0x780 mm/slub.c:5270
mt_alloc_one lib/maple_tree.c:174 [inline]
mas_alloc_nodes+0x280/0x390 lib/maple_tree.c:1110
mas_preallocate+0x39c/0xf10 lib/maple_tree.c:5194
vma_iter_prealloc mm/vma.h:505 [inline]
__split_vma+0x33d/0xe30 mm/vma.c:526
vms_gather_munmap_vmas+0x3aa/0x1320 mm/vma.c:1423
__mmap_setup mm/vma.c:2405 [inline]
__mmap_region+0x46e/0x2820 mm/vma.c:2734
mmap_region+0x180/0x3e0 mm/vma.c:2830
do_mmap+0xc63/0x12f0 mm/mmap.c:558
vm_mmap_pgoff+0x29e/0x470 mm/util.c:581
ksys_mmap_pgoff+0x328/0x5b0 mm/mmap.c:604
__do_sys_mmap arch/x86/kernel/sys_x86_64.c:89 [inline]
__se_sys_mmap arch/x86/kernel/sys_x86_64.c:82 [inline]
__x64_sys_mmap+0x125/0x190 arch/x86/kernel/sys_x86_64.c:82
do_syscall_x64 arch/x86/entry/syscall_64.c:63 [inline]
do_syscall_64+0xc9/0xf80 arch/x86/entry/syscall_64.c:94
entry_SYSCALL_64_after_hwframe+0x77/0x7f
RIP: 0033:0x7f935fb8f242
RSP: 002b:00007ffc4b98e898 EFLAGS: 00000206 ORIG_RAX: 0000000000000009
RAX: ffffffffffffffda RBX: 00007f935f8ad000 RCX: 00007f935fb8f242
RDX: 0000000000000001 RSI: 0000000000001000 RDI: 00007f935f8ad000
RBP: 0000000000000812 R08: 0000000000000003 R09: 0000000000004000
R10: 0000000000000812 R11: 0000000000000206 R12: 00007ffc4b98e920
R13: 00007f935fb64050 R14: 00007ffc4b98ecd0 R15: 00000fff89731d16
rcu: rcu_preempt kthread starved for 10506 jiffies! g15157 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:28408 pid:16 tgid:16 ppid:2 task_flags:0x208040 flags:0x00080000
Call Trace:
context_switch kernel/sched/core.c:5260 [inline]
__schedule+0xfe6/0x5fa0 kernel/sched/core.c:6867
rcu: Stack dump where RCU GP kthread last ran:
Sending NMI from CPU 0 to CPUs 1:
NMI backtrace for cpu 1
CPU: 1 UID: 0 PID: 6531 Comm: syz.3.32 Not tainted syzkaller #0 PREEMPT(full)
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/24/2026
RIP: 0010:csd_lock_wait kernel/smp.c:342 [inline]
RIP: 0010:smp_call_function_many_cond+0x576/0x14a0 kernel/smp.c:877
Code: b8 00 00 00 00 00 fc ff df 48 8b 54 24 10 49 89 d5 49 89 d4 49 c1 ed 03 41 83 e4 07 49 01 c5 41 83 c4 03 e8 5c 56 0c 00 f3 90 <41> 0f b6 45 00 41 38 c4 7c 08 84 c0 0f 85 3f 0d 00 00 8b 45 08 31
RSP: 0018:ffffc90003a2f360 EFLAGS: 00000293
RAX: 0000000000000000 RBX: 0000000000000000 RCX: ffffffff81faa90a
RDX: ffff888026d68000 RSI: ffffffff81faa8e4 RDI: ffff888026d68000
RBP: ffff8880b84431e0 R08: 0000000000000005 R09: 0000000000000000
R10: 0000000000000001 R11: 0000000000000000 R12: 0000000000000003
R13: ffffed101708863d R14: 0000000000000001 R15: ffff8880b853bf00
FS: 0000000000000000(0000) GS:ffff8881246d9000(0000) knlGS:0000000000000000
CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 0000200000000058 CR3: 00000000309ab000 CR4: 00000000003526f0
Call Trace:
on_each_cpu_cond_mask+0x40/0x90 kernel/smp.c:1043
__flush_tlb_multi arch/x86/include/asm/paravirt.h:91 [inline]
flush_tlb_multi arch/x86/mm/tlb.c:1382 [inline]
flush_tlb_mm_range+0x45f/0x1710 arch/x86/mm/tlb.c:1472
tlb_flush arch/x86/include/asm/tlb.h:23 [inline]
tlb_flush_mmu_tlbonly include/asm-generic/tlb.h:506 [inline]
tlb_flush_mmu_tlbonly include/asm-generic/tlb.h:496 [inline]
zap_pte_range mm/memory.c:1885 [inline]
zap_pmd_range mm/memory.c:1950 [inline]
zap_pud_range mm/memory.c:1978 [inline]
zap_p4d_range mm/memory.c:1999 [inline]
unmap_page_range+0x2360/0x43e0 mm/memory.c:2020
unmap_single_vma+0x153/0x240 mm/memory.c:2062
unmap_vmas+0x218/0x470 mm/memory.c:2104
exit_mmap+0x181/0xae0 mm/mmap.c:1277
__mmput+0x12a/0x410 kernel/fork.c:1173
mmput+0x67/0x80 kernel/fork.c:1196
exit_mm kernel/exit.c:581 [inline]
do_exit+0x78a/0x2a30 kernel/exit.c:959
do_group_exit+0xd5/0x2a0 kernel/exit.c:1112
get_signal+0x1ec7/0x21e0 kernel/signal.c:3034
arch_do_signal_or_restart+0x91/0x7a0 arch/x86/kernel/signal.c:337
__exit_to_user_mode_loop kernel/entry/common.c:41 [inline]
exit_to_user_mode_loop+0x86/0x4b0 kernel/entry/common.c:75
__exit_to_user_mode_prepare include/linux/irq-entry-common.h:226 [inline]
syscall_exit_to_user_mode_prepare include/linux/irq-entry-common.h:256 [inline]
syscall_exit_to_user_mode_work include/linux/entry-common.h:159 [inline]
syscall_exit_to_user_mode include/linux/entry-common.h:194 [inline]
do_syscall_64+0x4fe/0xf80 arch/x86/entry/syscall_64.c:100
entry_SYSCALL_64_after_hwframe+0x77/0x7f
RIP: 0033:0x7f6b6bd94ad7
Code: Unable to access opcode bytes at 0x7f6b6bd94aad.
RSP: 002b:00007ffe45f46b88 EFLAGS: 00000206 ORIG_RAX: 0000000000000027
RAX: 0000000000000019 RBX: 00007ffe45f46cf0 RCX: 00007f6b6bd94ad7
RDX: 00007ffe45f46bc0 RSI: 00007ffe45f46cf0 RDI: 0000000000000021
RBP: 0000000000000000 R08: 000000000000000f R09: 0000000000000000
R10: 00007f6b6c015fa0 R11: 0000000000000206 R12: 0000000000000000
R13: 00007f6b6c015fac R14: 00007f6b6c015fa8 R15: 00007f6b6c015fa0