[v6.1] INFO: rcu detected stall in sys_mlockall (2)

[syzbot]

Hello,

syzbot found the following issue on:

HEAD commit: 48d525b0e463 Linux 6.1.103
git tree: linux-6.1.y
console output: https://syzkaller.appspot.com/x/log.txt?x=14f559d3980000
kernel config: https://syzkaller.appspot.com/x/.config?x=2fb3032ebb754b2c
dashboard link: https://syzkaller.appspot.com/bug?extid=483c77c90a5d2b48f598
compiler: Debian clang version 15.0.6, GNU ld (GNU Binutils for Debian) 2.40

Unfortunately, I don't have any reproducer for this issue yet.

Downloadable assets:
disk image: https://storage.googleapis.com/syzbot-assets/07f111bf78d8/disk-48d525b0.raw.xz
vmlinux: https://storage.googleapis.com/syzbot-assets/99cfdc824bac/vmlinux-48d525b0.xz
kernel image: https://storage.googleapis.com/syzbot-assets/86360d7c4c73/bzImage-48d525b0.xz

IMPORTANT: if you fix the issue, please add the following tag to the commit:
Reported-by: syzbot+483c77...@syzkaller.appspotmail.com

rcu: INFO: rcu_preempt detected stalls on CPUs/tasks:
rcu: Tasks blocked on level-0 rcu_node (CPUs 0-1): P4817/1:b..l
(detected by 1, t=10502 jiffies, g=15221, q=350 ncpus=2)
task:syz.3.330 state:R running task stack:26456 pid:4817 ppid:3646 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:lock_is_held_type+0x137/0x180
Code: 75 40 48 c7 04 24 00 00 00 00 9c 8f 04 24 f7 04 24 00 02 00 00 75 46 41 f7 c4 00 02 00 00 74 01 fb 65 48 8b 04 25 28 00 00 00 <48> 3b 44 24 08 75 3c 89 e8 48 83 c4 10 5b 41 5c 41 5d 41 5e 41 5f
RSP: 0018:ffffc90004bbf8a8 EFLAGS: 00000206
RAX: b7d451d9fa951800 RBX: 0000000000000002 RCX: 0000000080000000
RDX: ffff8880273dd940 RSI: ffffffff8b0c13e0 RDI: ffffffff8b5d5de0
RBP: 0000000000000000 R08: ffffffff84250dbc R09: fffffbfff20e7245
R10: 0000000000000000 R11: dffffc0000000001 R12: 0000000000000246
R13: ffff8880273dd940 R14: 00000000ffffffff R15: ffffffff8d353858
lock_is_held include/linux/lockdep.h:283 [inline]
task_css include/linux/cgroup.h:509 [inline]
blkcg_css+0xc8/0x1c0 block/blk-cgroup.c:77
blk_cgroup_congested+0xb9/0x220 block/blk-cgroup.c:1998
__cgroup_throttle_swaprate+0x6d/0x1b0 mm/swapfile.c:3671
cgroup_throttle_swaprate include/linux/swap.h:662 [inline]
do_anonymous_page mm/memory.c:4178 [inline]
handle_pte_fault mm/memory.c:5011 [inline]
__handle_mm_fault mm/memory.c:5155 [inline]
handle_mm_fault+0x3b53/0x5340 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]
__do_sys_mlockall mm/mlock.c:721 [inline]
__se_sys_mlockall+0x32f/0x3c0 mm/mlock.c:697
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: 0033:0x7fb7b67779f9
RSP: 002b:00007fb7b7639038 EFLAGS: 00000246 ORIG_RAX: 0000000000000097
RAX: ffffffffffffffda RBX: 00007fb7b6905f80 RCX: 00007fb7b67779f9
RDX: 0000000000000000 RSI: 0000000000000000 RDI: 0000000000000001
RBP: 00007fb7b67e58ee R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000
R13: 0000000000000000 R14: 00007fb7b6905f80 R15: 00007fff8d7beee8
</TASK>
rcu: rcu_preempt kthread starved for 9767 jiffies! g15221 f0x0 RCU_GP_WAIT_FQS(5) ->state=0x0 ->cpu=0
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:27288 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 1 to CPUs 0:
NMI backtrace for cpu 0 skipped: idling at native_safe_halt arch/x86/include/asm/irqflags.h:51 [inline]
NMI backtrace for cpu 0 skipped: idling at arch_safe_halt arch/x86/include/asm/irqflags.h:89 [inline]
NMI backtrace for cpu 0 skipped: idling at acpi_safe_halt drivers/acpi/processor_idle.c:111 [inline]
NMI backtrace for cpu 0 skipped: idling at acpi_idle_do_entry+0x10f/0x340 drivers/acpi/processor_idle.c:567


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