rcu: INFO: rcu_preempt detected stalls on CPUs/tasks: rcu: Tasks blocked on level-0 rcu_node (CPUs 0-1): P20725/1:b..l P20728/1:b..l rcu: (detected by 0, t=10502 jiffies, g=139377, q=1066485 ncpus=1) task:syz.0.6245 state:R running task stack:26360 pid:20728 tgid:20728 ppid:5595 task_flags:0x40044c flags:0x00080002 Call Trace: context_switch kernel/sched/core.c:5526 [inline] __schedule+0x1259/0x6920 kernel/sched/core.c:7277 preempt_schedule_common+0x3c/0xb0 kernel/sched/core.c:7456 preempt_schedule_thunk+0x16/0x40 arch/x86/entry/thunk.S:12 __raw_spin_unlock include/linux/spinlock_api_smp.h:201 [inline] _raw_spin_unlock+0x3e/0x50 kernel/locking/spinlock.c:213 spin_unlock include/linux/spinlock.h:401 [inline] zap_pte_range mm/memory.c:2095 [inline] zap_pmd_range mm/memory.c:2151 [inline] zap_pud_range mm/memory.c:2179 [inline] zap_p4d_range mm/memory.c:2200 [inline] __zap_vma_range+0x16b0/0x48e0 mm/memory.c:2240 unmap_vmas+0x299/0x5f0 mm/memory.c:2309 exit_mmap+0x1ef/0xa00 mm/mmap.c:1315 __mmput+0x12a/0x410 kernel/fork.c:1193 mmput+0x67/0x80 kernel/fork.c:1216 exit_mm kernel/exit.c:617 [inline] do_exit+0x8b1/0x2ae0 kernel/exit.c:999 do_group_exit+0xd5/0x2a0 kernel/exit.c:1154 get_signal+0x1ec7/0x21e0 kernel/signal.c:3051 arch_do_signal_or_restart+0x91/0x7e0 arch/x86/kernel/signal.c:337 __exit_to_user_mode_loop kernel/entry/common.c:66 [inline] exit_to_user_mode_loop+0x139/0x700 kernel/entry/common.c:101 __exit_to_user_mode_prepare include/linux/irq-entry-common.h:207 [inline] syscall_exit_to_user_mode_prepare include/linux/irq-entry-common.h:230 [inline] syscall_exit_to_user_mode include/linux/entry-common.h:343 [inline] do_syscall_64+0x661/0x790 arch/x86/entry/syscall_64.c:89 entry_SYSCALL_64_after_hwframe+0x77/0x7f RIP: 0033:0x7fe93519e159 RSP: 002b:00007fff54669f68 EFLAGS: 00000246 ORIG_RAX: 00000000000000ca RAX: ffffffffffffff92 RBX: 0000000000085c4c RCX: 00007fe93519e159 RDX: 0000000000000000 RSI: 0000000000000080 RDI: 00007fe935425fac RBP: 0000000000000bea R08: 0000000000000001 R09: 0000000000000000 R10: 00007fff5466a070 R11: 0000000000000246 R12: 00007fff5466a090 R13: 00007fe935425fac R14: 0000000000086836 R15: 00007fff5466a070 task:syz.4.6243 state:R running task stack:27160 pid:20725 tgid:20723 ppid:17745 task_flags:0x40054c flags:0x00080001 Call Trace: context_switch kernel/sched/core.c:5526 [inline] __schedule+0x1259/0x6920 kernel/sched/core.c:7277 preempt_schedule_irq+0x4e/0x90 kernel/sched/core.c:7599 irqentry_exit_to_kernel_mode_preempt include/linux/irq-entry-common.h:468 [inline] irqentry_exit_to_kernel_mode include/linux/irq-entry-common.h:539 [inline] irqentry_exit+0x205/0xa10 kernel/entry/common.c:167 asm_sysvec_apic_timer_interrupt+0x1a/0x20 arch/x86/include/asm/idtentry.h:674 RIP: 0010:lock_release+0x1b9/0x310 kernel/locking/lockdep.c:5968 Code: 00 00 41 f7 c6 00 02 00 00 0f 85 c8 00 00 00 48 8b 44 24 10 65 48 2b 05 1d 29 a5 12 0f 85 4d 01 00 00 48 83 c4 18 5b 5d 41 5c <41> 5e 41 5f c3 cc cc cc cc 65 8b 05 2f 29 a5 12 83 f8 07 0f 87 c8 RSP: 0018:ffffc90004b9f178 EFLAGS: 00000296 RAX: 0000000000000000 RBX: ffffc90004b9f840 RCX: ffffc90004b9f154 RDX: 0000000000000000 RSI: ffffffff8e365ea9 RDI: ffffffff8c622e80 RBP: 0000000000000001 R08: 0000000000000001 R09: 0000000000000007 R10: 0000000000000200 R11: 000000000000f0db R12: ffffc90004b9f250 R13: ffffc90004b9f200 R14: 0000000000000202 R15: 0000000000000003 rcu_lock_release include/linux/rcupdate.h:319 [inline] rcu_read_unlock include/linux/rcupdate.h:880 [inline] class_rcu_destructor include/linux/rcupdate.h:1216 [inline] unwind_next_frame+0x3c3/0x2090 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:4683 [inline] slab_alloc_node mm/slub.c:4996 [inline] kmem_cache_alloc_noprof+0x269/0x6a0 mm/slub.c:5010 kmem_alloc_batch+0x49/0x170 lib/debugobjects.c:371 fill_pool lib/debugobjects.c:420 [inline] debug_objects_fill_pool lib/debugobjects.c:780 [inline] debug_objects_fill_pool+0x24d/0x590 lib/debugobjects.c:758 debug_object_activate+0x103/0x4b0 lib/debugobjects.c:869 debug_rcu_head_queue kernel/rcu/rcu.h:245 [inline] __call_rcu_common.constprop.0+0x35/0x9b0 kernel/rcu/tree.c:3166 slab_free_hook mm/slub.c:2712 [inline] slab_free mm/slub.c:6508 [inline] kmem_cache_free+0x43b/0x6c0 mm/slub.c:6635 tear_down_vmas+0x2a5/0x610 mm/mmap.c:1277 exit_mmap+0x469/0xa00 mm/mmap.c:1335 __mmput+0x12a/0x410 kernel/fork.c:1193 mmput+0x67/0x80 kernel/fork.c:1216 exit_mm kernel/exit.c:617 [inline] do_exit+0x8b1/0x2ae0 kernel/exit.c:999 do_group_exit+0xd5/0x2a0 kernel/exit.c:1154 get_signal+0x1ec7/0x21e0 kernel/signal.c:3051 arch_do_signal_or_restart+0x91/0x7e0 arch/x86/kernel/signal.c:337 __exit_to_user_mode_loop kernel/entry/common.c:66 [inline] exit_to_user_mode_loop+0x139/0x700 kernel/entry/common.c:101 __exit_to_user_mode_prepare include/linux/irq-entry-common.h:207 [inline] syscall_exit_to_user_mode_prepare include/linux/irq-entry-common.h:230 [inline] syscall_exit_to_user_mode include/linux/entry-common.h:343 [inline] do_syscall_64+0x661/0x790 arch/x86/entry/syscall_64.c:89 entry_SYSCALL_64_after_hwframe+0x77/0x7f RIP: 0033:0x7f0efb59e159 RSP: 002b:00007f0efc394028 EFLAGS: 00000246 ORIG_RAX: 0000000000000001 RAX: ffffffffffffffea RBX: 00007f0efb825fa0 RCX: 00007f0efb59e159 RDX: 0000000000000000 RSI: 0000000000000000 RDI: 0000000000000003 RBP: 00007f0efb63506b R08: 0000000000000000 R09: 0000000000000000 R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000 R13: 00007f0efb826038 R14: 00007f0efb825fa0 R15: 00007ffde93df5f8