syzbot

rcu: INFO: rcu_preempt detected stalls on CPUs/tasks:
rcu: 	Tasks blocked on level-0 rcu_node (CPUs 0-1): P5492/1:b..l
	(detected by 0, t=10502 jiffies, g=18169, q=142 ncpus=2)
task:syz.2.531       state:R  running task     stack:24792 pid:5492  ppid:3642   flags:0x00004000
Call Trace:
 <TASK>
 context_switch kernel/sched/core.c:5241 [inline]
 __schedule+0x143f/0x4570 kernel/sched/core.c:6558
 preempt_schedule_irq+0xf7/0x1c0 kernel/sched/core.c:6870
 irqentry_exit+0x53/0x80 kernel/entry/common.c:439
 asm_sysvec_apic_timer_interrupt+0x16/0x20 arch/x86/include/asm/idtentry.h:653
RIP: 0010:__kasan_check_read+0x6/0x10 mm/kasan/shadow.c:31
Code: 41 5e 41 5f 5d c3 48 c7 c7 54 96 b7 8c eb 0a 48 c7 c7 8c 96 b7 8c 4c 89 fe e8 c6 f9 c0 08 31 db eb d7 cc cc 89 f6 48 8b 0c 24 <31> d2 e9 d3 ec ff ff 0f 1f 00 89 f6 48 8b 0c 24 ba 01 00 00 00 e9
RSP: 0018:ffffc9000531f1f8 EFLAGS: 00000246
RAX: 0000000000000000 RBX: 0000000000000001 RCX: ffffffff816a72bb
RDX: 0000000000000000 RSI: 0000000000000008 RDI: ffffffff8e99c4a8
RBP: ffffc9000531f350 R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: dffffc0000000001 R12: 1ffff92000a63e48
R13: dffffc0000000000 R14: 0000000000000000 R15: 0000000000000000
 instrument_atomic_read include/linux/instrumented.h:72 [inline]
 _test_bit include/asm-generic/bitops/instrumented-non-atomic.h:141 [inline]
 cpumask_test_cpu include/linux/cpumask.h:444 [inline]
 cpu_online include/linux/cpumask.h:1030 [inline]
 trace_lock_acquire include/trace/events/lock.h:24 [inline]
 lock_acquire+0xeb/0x5a0 kernel/locking/lockdep.c:5633
 rcu_lock_acquire include/linux/rcupdate.h:350 [inline]
 rcu_read_lock include/linux/rcupdate.h:791 [inline]
 percpu_ref_put_many include/linux/percpu-refcount.h:330 [inline]
 percpu_ref_put+0x36/0x180 include/linux/percpu-refcount.h:351
 css_put include/linux/cgroup.h:407 [inline]
 __mem_cgroup_charge+0x55/0x80 mm/memcontrol.c:6921
 mem_cgroup_charge include/linux/memcontrol.h:672 [inline]
 shmem_add_to_page_cache+0xaa6/0x1e60 mm/shmem.c:708
 shmem_get_folio_gfp+0x164e/0x3470 mm/shmem.c:1971
 shmem_fault+0x235/0x9c0 mm/shmem.c:2156
 __do_fault+0x136/0x4f0 mm/memory.c:4261
 do_read_fault mm/memory.c:4612 [inline]
 do_fault mm/memory.c:4741 [inline]
 handle_pte_fault mm/memory.c:5013 [inline]
 __handle_mm_fault mm/memory.c:5155 [inline]
 handle_mm_fault+0x3412/0x5340 mm/memory.c:5276
 faultin_page mm/gup.c:1009 [inline]
 __get_user_pages+0x4f3/0x1190 mm/gup.c:1233
 populate_vma_page_range+0x217/0x2b0 mm/gup.c:1590
 __mm_populate+0x275/0x440 mm/gup.c:1704
 mm_populate include/linux/mm.h:2797 [inline]
 vm_mmap_pgoff+0x22b/0x2d0 mm/util.c:525
 do_syscall_x64 arch/x86/entry/common.c:51 [inline]
 do_syscall_64+0x3b/0xb0 arch/x86/entry/common.c:81
 entry_SYSCALL_64_after_hwframe+0x68/0xd2
RIP: 0033:0x7fa8d45779f9
RSP: 002b:00007fa8d5423038 EFLAGS: 00000246 ORIG_RAX: 0000000000000009
RAX: ffffffffffffffda RBX: 00007fa8d4705f80 RCX: 00007fa8d45779f9
RDX: 000000000000000f RSI: 0000000000b36000 RDI: 0000000020000000
RBP: 00007fa8d45e58ee R08: ffffffffffffffff R09: 0000000000000000
R10: 0000000004008031 R11: 0000000000000246 R12: 0000000000000000
R13: 0000000000000001 R14: 00007fa8d4705f80 R15: 00007fffa348b4e8
 </TASK>
rcu: rcu_preempt kthread starved for 9859 jiffies! g18169 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:25528 pid:16    ppid:2      flags:0x00004000
Call Trace:
 <TASK>
 context_switch kernel/sched/core.c:5241 [inline]
 __schedule+0x143f/0x4570 kernel/sched/core.c:6558
 schedule+0xbf/0x180 kernel/sched/core.c:6634
 schedule_timeout+0x1b9/0x300 kernel/time/timer.c:1965
 rcu_gp_fqs_loop+0x2d2/0x1150 kernel/rcu/tree.c:1706
 rcu_gp_kthread+0xa3/0x3b0 kernel/rcu/tree.c:1905
 kthread+0x28d/0x320 kernel/kthread.c:376
 ret_from_fork+0x1f/0x30 arch/x86/entry/entry_64.S:295
 </TASK>
rcu: Stack dump where RCU GP kthread last ran:
Sending NMI from CPU 0 to CPUs 1:
NMI backtrace for cpu 1 skipped: idling at native_safe_halt arch/x86/include/asm/irqflags.h:51 [inline]
NMI backtrace for cpu 1 skipped: idling at arch_safe_halt arch/x86/include/asm/irqflags.h:89 [inline]
NMI backtrace for cpu 1 skipped: idling at acpi_safe_halt drivers/acpi/processor_idle.c:111 [inline]
NMI backtrace for cpu 1 skipped: idling at acpi_idle_do_entry+0x10f/0x340 drivers/acpi/processor_idle.c:567