rcu: INFO: rcu_preempt detected stalls on CPUs/tasks: rcu: Tasks blocked on level-0 rcu_node (CPUs 0-1): P7498/1:b..l rcu: (detected by 1, t=10503 jiffies, g=16233, q=668 ncpus=2) task:syz.1.414 state:R running task stack:26632 pid:7498 tgid:7495 ppid:5829 task_flags:0x40054c flags:0x00004006 Call Trace: context_switch kernel/sched/core.c:5382 [inline] __schedule+0x116f/0x5de0 kernel/sched/core.c:6767 preempt_schedule_irq+0x51/0x90 kernel/sched/core.c:7090 irqentry_exit+0x36/0x90 kernel/entry/common.c:354 asm_sysvec_apic_timer_interrupt+0x1a/0x20 arch/x86/include/asm/idtentry.h:702 RIP: 0010:__sanitizer_cov_trace_pc+0x66/0x70 kernel/kcov.c:235 Code: 82 18 16 00 00 83 f8 02 75 20 48 8b 8a 20 16 00 00 8b 92 1c 16 00 00 48 8b 01 48 83 c0 01 48 39 d0 73 07 48 89 01 48 89 34 c1 cc cc cc cc 0f 1f 44 00 00 90 90 90 90 90 90 90 90 90 90 90 90 RSP: 0018:ffffc90003e2f8a0 EFLAGS: 00000293 RAX: 0000000000000000 RBX: 0000000000000001 RCX: ffffffff822c33d9 RDX: ffff88807a158000 RSI: ffffffff822c3215 RDI: 0000000000000001 RBP: 0000000000000001 R08: 0000000000000001 R09: 0000000000000000 R10: 0000000000000001 R11: 0000000000000000 R12: ffff88801d18c6d0 R13: ffff88801d18c6cc R14: 0000000000000000 R15: dffffc0000000000 rcu_lock_release include/linux/rcupdate.h:341 [inline] rcu_read_unlock include/linux/rcupdate.h:871 [inline] __page_table_check_zero+0x315/0x5b0 mm/page_table_check.c:145 page_table_check_free include/linux/page_table_check.h:41 [inline] free_pages_prepare mm/page_alloc.c:1263 [inline] __free_frozen_pages+0x704/0xff0 mm/page_alloc.c:2680 discard_slab mm/slub.c:2720 [inline] __put_partials+0x16d/0x1c0 mm/slub.c:3189 qlink_free mm/kasan/quarantine.c:163 [inline] qlist_free_all+0x4e/0x120 mm/kasan/quarantine.c:179 kasan_quarantine_reduce+0x195/0x1e0 mm/kasan/quarantine.c:286 __kasan_slab_alloc+0x69/0x90 mm/kasan/common.c:329 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+0x1cb/0x3b0 mm/slub.c:4207 taskstats_tgid_alloc kernel/taskstats.c:576 [inline] taskstats_exit+0x654/0xbe0 kernel/taskstats.c:615 do_exit+0x85f/0x2c30 kernel/exit.c:938 do_group_exit+0xd3/0x2a0 kernel/exit.c:1102 get_signal+0x2673/0x26d0 kernel/signal.c:3034 arch_do_signal_or_restart+0x8f/0x7d0 arch/x86/kernel/signal.c:337 exit_to_user_mode_loop kernel/entry/common.c:111 [inline] exit_to_user_mode_prepare include/linux/entry-common.h:329 [inline] __syscall_exit_to_user_mode_work kernel/entry/common.c:207 [inline] syscall_exit_to_user_mode+0x150/0x2a0 kernel/entry/common.c:218 do_syscall_64+0xda/0x260 arch/x86/entry/syscall_64.c:100 entry_SYSCALL_64_after_hwframe+0x77/0x7f RIP: 0033:0x7f12e2d8d169 RSP: 002b:00007f12e3ca9038 EFLAGS: 00000246 ORIG_RAX: 0000000000000014 RAX: 0000000000007f7f RBX: 00007f12e2fa5fa0 RCX: 00007f12e2d8d169 RDX: 0000000000000002 RSI: 0000200000000840 RDI: 0000000000000008 RBP: 00007f12e2e0e2a0 R08: 0000000000000000 R09: 0000000000000000 R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000 R13: 0000000000000000 R14: 00007f12e2fa5fa0 R15: 00007fff03a1ed18