syzbot

rcu: INFO: rcu_preempt detected stalls on CPUs/tasks:
rcu: 	Tasks blocked on level-0 rcu_node (CPUs 0-1): P10818/1:b..l
rcu: 	(detected by 0, t=10503 jiffies, g=51013, q=1979 ncpus=2)
task:syz.0.1664      state:R  running task     stack:25352 pid:10818 tgid:10816 ppid:5853   task_flags:0x400040 flags:0x00004004
Call Trace:
 <TASK>
 context_switch kernel/sched/core.c:5396 [inline]
 __schedule+0x16f5/0x4d00 kernel/sched/core.c:6785
 preempt_schedule_irq+0xb5/0x150 kernel/sched/core.c:7108
 irqentry_exit+0x6f/0x90 kernel/entry/common.c:307
 asm_sysvec_apic_timer_interrupt+0x1a/0x20 arch/x86/include/asm/idtentry.h:702
RIP: 0010:lock_acquire+0x175/0x360 kernel/locking/lockdep.c:5875
Code: 00 00 00 00 9c 8f 44 24 30 f7 44 24 30 00 02 00 00 0f 85 cd 00 00 00 f7 44 24 08 00 02 00 00 74 01 fb 65 48 8b 05 1b 0a fe 10 <48> 3b 44 24 58 0f 85 f2 00 00 00 48 83 c4 60 5b 41 5c 41 5d 41 5e
RSP: 0000:ffffc9000cddf058 EFLAGS: 00000206
RAX: 800b2c3fd1e10300 RBX: 0000000000000000 RCX: 800b2c3fd1e10300
RDX: 0000000000000000 RSI: ffffffff8db66a62 RDI: ffffffff8be27240
RBP: ffffffff81729e15 R08: 0000000000000000 R09: ffffffff81729e15
R10: ffffc9000cddf228 R11: fffff520019bbe51 R12: 0000000000000002
R13: ffffffff8e13f060 R14: 0000000000000000 R15: 0000000000000246
 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+0xc2/0x2390 arch/x86/kernel/unwind_orc.c:479
 __unwind_start+0x5b9/0x760 arch/x86/kernel/unwind_orc.c:758
 unwind_start arch/x86/include/asm/unwind.h:64 [inline]
 arch_stack_walk+0xe4/0x150 arch/x86/kernel/stacktrace.c:24
 stack_trace_save+0x9c/0xe0 kernel/stacktrace.c:122
 save_stack+0xf5/0x1f0 mm/page_owner.c:156
 __reset_page_owner+0x71/0x1f0 mm/page_owner.c:308
 reset_page_owner include/linux/page_owner.h:25 [inline]
 free_pages_prepare mm/page_alloc.c:1248 [inline]
 __free_frozen_pages+0xc71/0xe70 mm/page_alloc.c:2706
 discard_slab mm/slub.c:2716 [inline]
 __put_partials+0x161/0x1c0 mm/slub.c:3185
 put_cpu_partial+0x17c/0x250 mm/slub.c:3260
 __slab_free+0x2f7/0x400 mm/slub.c:4512
 qlink_free mm/kasan/quarantine.c:163 [inline]
 qlist_free_all+0x97/0x140 mm/kasan/quarantine.c:179
 kasan_quarantine_reduce+0x148/0x160 mm/kasan/quarantine.c:286
 __kasan_kmalloc_large+0x1c/0xa0 mm/kasan/common.c:426
 kasan_kmalloc_large include/linux/kasan.h:270 [inline]
 ___kmalloc_large_node+0x15a/0x210 mm/slub.c:4279
 __kmalloc_large_node_noprof+0x18/0x90 mm/slub.c:4299
 __do_kmalloc_node mm/slub.c:4315 [inline]
 __kmalloc_noprof+0x36f/0x4f0 mm/slub.c:4339
 kmalloc_noprof include/linux/slab.h:909 [inline]
 temp_kmalloc drivers/iommu/iommufd/pages.c:89 [inline]
 __batch_init drivers/iommu/iommufd/pages.c:322 [inline]
 batch_init_backup drivers/iommu/iommufd/pages.c:341 [inline]
 iopt_pages_unfill_xarray+0x443/0xaa0 drivers/iommu/iommufd/pages.c:1743
 iopt_area_remove_access+0x262/0x330 drivers/iommu/iommufd/pages.c:2187
 iommufd_access_unpin_pages+0x309/0x4b0 drivers/iommu/iommufd/device.c:1264
 iommufd_test_access_unmap+0x28c/0x300 drivers/iommu/iommufd/selftest.c:1305
 iommufd_test_staccess_release+0x6a/0xb0 drivers/iommu/iommufd/selftest.c:1346
 __fput+0x449/0xa70 fs/file_table.c:465
 task_work_run+0x1d4/0x260 kernel/task_work.c:227
 resume_user_mode_work include/linux/resume_user_mode.h:50 [inline]
 exit_to_user_mode_loop+0xec/0x110 kernel/entry/common.c:114
 exit_to_user_mode_prepare include/linux/entry-common.h:330 [inline]
 syscall_exit_to_user_mode_work include/linux/entry-common.h:414 [inline]
 syscall_exit_to_user_mode include/linux/entry-common.h:449 [inline]
 do_syscall_64+0x2bd/0x3b0 arch/x86/entry/syscall_64.c:100
 entry_SYSCALL_64_after_hwframe+0x77/0x7f
RIP: 0033:0x7f29ec18e969
RSP: 002b:00007f29ed0b0038 EFLAGS: 00000246 ORIG_RAX: 0000000000000010
RAX: 0000000000000000 RBX: 00007f29ec3b6080 RCX: 00007f29ec18e969
RDX: 00002000000008c0 RSI: 0000000000003ba0 RDI: 0000000000000006
RBP: 00007f29ec210ab1 R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000
R13: 0000000000000000 R14: 00007f29ec3b6080 R15: 00007f29ec4dfa28
 </TASK>