rcu: INFO: rcu_preempt detected stalls on CPUs/tasks: rcu: Tasks blocked on level-0 rcu_node (CPUs 0-1): P5842/1:b..l rcu: (detected by 0, t=10503 jiffies, g=21829, q=1967 ncpus=2) task:syz-executor state:R running task stack:20680 pid:5842 tgid:5842 ppid:1 task_flags:0x400140 flags:0x00000004 Call Trace: context_switch kernel/sched/core.c:5382 [inline] __schedule+0x1b88/0x5240 kernel/sched/core.c:6767 preempt_schedule_irq+0xfe/0x1c0 kernel/sched/core.c:7090 irqentry_exit+0x5e/0x90 kernel/entry/common.c:354 asm_sysvec_apic_timer_interrupt+0x1a/0x20 arch/x86/include/asm/idtentry.h:702 RIP: 0010:lock_acquire+0x167/0x2f0 arch/x86/include/asm/irqflags.h:-1 Code: c7 44 24 10 00 00 00 00 9c 8f 44 24 10 f7 44 24 10 00 02 00 00 0f 85 fd 00 00 00 41 f7 c6 00 02 00 00 74 01 fb 65 48 8b 45 00 <48> 3b 44 24 38 0f 85 72 01 00 00 48 83 c4 40 5b 41 5c 41 5d 41 5e RSP: 0018:ffffc9000460ec48 EFLAGS: 00000206 RAX: 85fee81cafe4c000 RBX: ffffffff8ed3dfe0 RCX: 85fee81cafe4c000 RDX: 0000000000000000 RSI: ffffffff8e4fce8a RDI: ffffffff8ca1b120 RBP: ffffffff9368a020 R08: 0000000000000000 R09: 0000000000000000 R10: 0000000000000000 R11: 0000000000000000 R12: 0000000000000000 R13: 0000000000000002 R14: 0000000000000246 R15: 0000000000000000 rcu_lock_acquire include/linux/rcupdate.h:331 [inline] rcu_read_lock include/linux/rcupdate.h:841 [inline] class_rcu_constructor include/linux/rcupdate.h:1155 [inline] unwind_next_frame+0xd5/0x23b0 arch/x86/kernel/unwind_orc.c:479 arch_stack_walk+0x11e/0x150 arch/x86/kernel/stacktrace.c:25 stack_trace_save+0x11a/0x1d0 kernel/stacktrace.c:122 kasan_save_stack mm/kasan/common.c:47 [inline] kasan_save_track+0x3f/0x80 mm/kasan/common.c:68 unpoison_slab_object mm/kasan/common.c:319 [inline] __kasan_slab_alloc+0x66/0x80 mm/kasan/common.c:345 kasan_slab_alloc include/linux/kasan.h:250 [inline] slab_post_alloc_hook mm/slub.c:4151 [inline] slab_alloc_node mm/slub.c:4200 [inline] kmem_cache_alloc_noprof+0x1e1/0x390 mm/slub.c:4207 ptlock_alloc+0x20/0x70 mm/memory.c:7354 ptlock_init include/linux/mm.h:3057 [inline] pagetable_pte_ctor include/linux/mm.h:3105 [inline] __pte_alloc_one_noprof include/asm-generic/pgalloc.h:73 [inline] pte_alloc_one+0x6d/0x160 arch/x86/mm/pgtable.c:17 __pte_alloc+0x7b/0x240 mm/memory.c:430 copy_pte_range+0x607b/0x6680 mm/memory.c:1100 copy_pmd_range mm/memory.c:1255 [inline] copy_pud_range mm/memory.c:1292 [inline] copy_p4d_range mm/memory.c:1316 [inline] copy_page_range+0xe57/0x13a0 mm/memory.c:1410 dup_mmap kernel/fork.c:726 [inline] dup_mm kernel/fork.c:1734 [inline] copy_mm+0x130d/0x22c0 kernel/fork.c:1786 copy_process+0x17de/0x3d10 kernel/fork.c:2429 kernel_clone+0x242/0x930 kernel/fork.c:2844 __do_sys_clone kernel/fork.c:2987 [inline] __se_sys_clone kernel/fork.c:2971 [inline] __x64_sys_clone+0x268/0x2e0 kernel/fork.c:2971 do_syscall_x64 arch/x86/entry/syscall_64.c:63 [inline] do_syscall_64+0xf3/0x230 arch/x86/entry/syscall_64.c:94 entry_SYSCALL_64_after_hwframe+0x77/0x7f RIP: 0033:0x7fbba45839d3 RSP: 002b:00007fff55445728 EFLAGS: 00000246 ORIG_RAX: 0000000000000038 RAX: ffffffffffffffda RBX: 0000000000000000 RCX: 00007fbba45839d3 RDX: 0000000000000000 RSI: 0000000000000000 RDI: 0000000001200011 RBP: 0000000000000001 R08: 0000000000000000 R09: 0000000000000001 R10: 000055557d5077d0 R11: 0000000000000246 R12: 0000000000000000 R13: 00000000000927c0 R14: 00000000000271c4 R15: 00007fff554458c0