[v6.1] INFO: rcu detected stall in sys_creat

[syzbot]

Hello,

syzbot found the following issue on:

HEAD commit: 6c44e13dc284 Linux 6.1.46
git tree: linux-6.1.y
console output: https://syzkaller.appspot.com/x/log.txt?x=12f2f7f3a80000
kernel config: https://syzkaller.appspot.com/x/.config?x=d53bfb03cd3f0d5d
dashboard link: https://syzkaller.appspot.com/bug?extid=ee51aa0ec51dd5807eba
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/706045968752/disk-6c44e13d.raw.xz
vmlinux: https://storage.googleapis.com/syzbot-assets/2f25349b69b4/vmlinux-6c44e13d.xz
kernel image: https://storage.googleapis.com/syzbot-assets/e6791616e516/bzImage-6c44e13d.xz

IMPORTANT: if you fix the issue, please add the following tag to the commit:
Reported-by: syzbot+ee51aa...@syzkaller.appspotmail.com

rcu: INFO: rcu_preempt detected stalls on CPUs/tasks:
rcu: Tasks blocked on level-0 rcu_node (CPUs 0-1): P4087/1:b..l P5768/1:b..l
(detected by 1, t=10502 jiffies, g=191981, q=21 ncpus=2)
task:syz-executor.4 state:R running task stack:24552 pid:5768 ppid:3557 flags:0x00004006
Call Trace:
<TASK>
context_switch kernel/sched/core.c:5241 [inline]
__schedule+0x132c/0x4330 kernel/sched/core.c:6554
preempt_schedule_irq+0xf7/0x1c0 kernel/sched/core.c:6866
irqentry_exit+0x53/0x80 kernel/entry/common.c:433
asm_sysvec_apic_timer_interrupt+0x16/0x20 arch/x86/include/asm/idtentry.h:649
RIP: 0010:lock_is_held include/linux/lockdep.h:283 [inline]
RIP: 0010:rcu_read_lock_held+0x2a/0x40 kernel/rcu/update.c:311
Code: 53 e8 0a 3a 13 09 85 c0 74 26 31 db e8 bf 3a 01 00 84 c0 74 20 e8 26 3c 01 00 84 c0 74 17 48 c7 c7 e0 9e 12 8d be ff ff ff ff <5b> e9 70 36 13 09 bb 01 00 00 00 89 d8 5b c3 0f 1f 80 00 00 00 00
RSP: 0018:ffffc9000478f130 EFLAGS: 00000202
RAX: 1ffffffff1a25d01 RBX: 0000000000000000 RCX: 0000000080000000
RDX: ffffc9000b293000 RSI: 00000000ffffffff RDI: ffffffff8d129ee0
RBP: 0000000000000220 R08: ffffffff81eb0a35 R09: fffffbfff2093445
R10: 0000000000000000 R11: dffffc0000000001 R12: 0000000000000000
R13: ffffea0002227540 R14: ffff8880155c0000 R15: 00000000000889d5
lookup_page_ext mm/page_ext.c:277 [inline]
page_ext_get+0x169/0x270 mm/page_ext.c:158
__page_table_check_zero+0x139/0x4a0 mm/page_table_check.c:140
page_table_check_free include/linux/page_table_check.h:46 [inline]
free_pages_prepare mm/page_alloc.c:1461 [inline]
free_pcp_prepare mm/page_alloc.c:1510 [inline]
free_unref_page_prepare+0xf73/0x1120 mm/page_alloc.c:3388
free_unref_page_list+0x107/0x810 mm/page_alloc.c:3530
release_pages+0x2836/0x2b40 mm/swap.c:1055
__pagevec_release+0x80/0xf0 mm/swap.c:1075
pagevec_release include/linux/pagevec.h:71 [inline]
folio_batch_release include/linux/pagevec.h:135 [inline]
truncate_inode_pages_range+0x48a/0x1340 mm/truncate.c:373
truncate_inode_pages mm/truncate.c:452 [inline]
truncate_pagecache+0x68/0x80 mm/truncate.c:753
ext4_setattr+0xfb2/0x1a00 fs/ext4/inode.c:5566
notify_change+0xdcd/0x1080 fs/attr.c:482
do_truncate+0x21c/0x300 fs/open.c:65
handle_truncate fs/namei.c:3216 [inline]
do_open fs/namei.c:3561 [inline]
path_openat+0x27e2/0x2e60 fs/namei.c:3714
do_filp_open+0x230/0x480 fs/namei.c:3741
do_sys_openat2+0x13b/0x500 fs/open.c:1318
do_sys_open fs/open.c:1334 [inline]
__do_sys_creat fs/open.c:1410 [inline]
__se_sys_creat fs/open.c:1404 [inline]
__x64_sys_creat+0x11f/0x160 fs/open.c:1404
do_syscall_x64 arch/x86/entry/common.c:50 [inline]
do_syscall_64+0x3d/0xb0 arch/x86/entry/common.c:80
entry_SYSCALL_64_after_hwframe+0x63/0xcd
RIP: 0033:0x7f285167cae9
RSP: 002b:00007f285233b0c8 EFLAGS: 00000246 ORIG_RAX: 0000000000000055
RAX: ffffffffffffffda RBX: 00007f285179c050 RCX: 00007f285167cae9
RDX: 0000000000000000 RSI: 0000000000000000 RDI: 0000000020000000
RBP: 00007f28516c847a R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000
R13: 000000000000006e R14: 00007f285179c050 R15: 00007ffeadd88918
</TASK>
task:kworker/u4:17 state:R running task stack:22200 pid:4087 ppid:2 flags:0x00004000
Workqueue: bat_events batadv_iv_send_outstanding_bat_ogm_packet
Call Trace:
<TASK>
context_switch kernel/sched/core.c:5241 [inline]
__schedule+0x132c/0x4330 kernel/sched/core.c:6554
preempt_schedule_irq+0xf7/0x1c0 kernel/sched/core.c:6866
irqentry_exit+0x53/0x80 kernel/entry/common.c:433
asm_sysvec_apic_timer_interrupt+0x16/0x20 arch/x86/include/asm/idtentry.h:649
RIP: 0010:lock_acquire+0x26f/0x5a0 kernel/locking/lockdep.c:5673
Code: 2b 00 74 08 4c 89 f7 e8 df a2 76 00 f6 44 24 61 02 0f 85 84 01 00 00 41 f7 c7 00 02 00 00 74 01 fb 48 c7 44 24 40 0e 36 e0 45 <4b> c7 44 25 00 00 00 00 00 43 c7 44 25 09 00 00 00 00 43 c7 44 25
RSP: 0018:ffffc9000ac9f8e0 EFLAGS: 00000206
RAX: 0000000000000001 RBX: 1ffff92001593f28 RCX: 1ffff92001593ec8
RDX: dffffc0000000000 RSI: ffffffff8aebf3a0 RDI: ffffffff8b3ceae0
RBP: ffffc9000ac9fa40 R08: dffffc0000000000 R09: fffffbfff2093445
R10: 0000000000000000 R11: dffffc0000000001 R12: 1ffff92001593f24
R13: dffffc0000000000 R14: ffffc9000ac9f940 R15: 0000000000000246
rcu_lock_acquire+0x2a/0x30 include/linux/rcupdate.h:306
rcu_read_lock include/linux/rcupdate.h:747 [inline]
batadv_iv_ogm_slide_own_bcast_window net/batman-adv/bat_iv_ogm.c:755 [inline]
batadv_iv_ogm_schedule_buff net/batman-adv/bat_iv_ogm.c:826 [inline]
batadv_iv_ogm_schedule+0x425/0x1000 net/batman-adv/bat_iv_ogm.c:869
batadv_iv_send_outstanding_bat_ogm_packet+0x6fa/0x800 net/batman-adv/bat_iv_ogm.c:1713
process_one_work+0x8aa/0x11f0 kernel/workqueue.c:2292
worker_thread+0xa5f/0x1210 kernel/workqueue.c:2439
kthread+0x26e/0x300 kernel/kthread.c:376
ret_from_fork+0x1f/0x30 arch/x86/entry/entry_64.S:306
</TASK>
rcu: rcu_preempt kthread timer wakeup didn't happen for 10501 jiffies! g191981 f0x0 RCU_GP_WAIT_FQS(5) ->state=0x402
rcu: Possible timer handling issue on cpu=0 timer-softirq=183509
rcu: rcu_preempt kthread starved for 10502 jiffies! g191981 f0x0 RCU_GP_WAIT_FQS(5) ->state=0x402 ->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:I stack:26008 pid:16 ppid:2 flags:0x00004000
Call Trace:
<TASK>
context_switch kernel/sched/core.c:5241 [inline]
__schedule+0x132c/0x4330 kernel/sched/core.c:6554
schedule+0xbf/0x180 kernel/sched/core.c:6630
schedule_timeout+0x1b9/0x300 kernel/time/timer.c:1935
rcu_gp_fqs_loop+0x2c2/0x1010 kernel/rcu/tree.c:1661
rcu_gp_kthread+0xa3/0x3a0 kernel/rcu/tree.c:1860
kthread+0x26e/0x300 kernel/kthread.c:376
ret_from_fork+0x1f/0x30 arch/x86/entry/entry_64.S:306
</TASK>
rcu: Stack dump where RCU GP kthread last ran:
Sending NMI from CPU 1 to CPUs 0:
NMI backtrace for cpu 0
CPU: 0 PID: 4810 Comm: kworker/u4:6 Not tainted 6.1.46-syzkaller #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 07/26/2023
Workqueue: netns cleanup_net
RIP: 0010:advance_sched+0x3c2/0x940 net/sched/sch_taprio.c:734
Code: 28 8b 03 48 01 c5 48 8b 44 24 08 48 8d 58 28 48 89 d8 48 c1 e8 03 42 80 3c 30 00 4c 8b 64 24 20 74 08 48 89 df e8 ee 19 2a f9 <4c> 8b 3b 4c 39 fd 4c 0f 4c fd 4d 85 e4 0f 84 88 00 00 00 4c 89 f0
RSP: 0018:ffffc90000007cc0 EFLAGS: 00000046
RAX: 1ffff1100fba91a5 RBX: ffff88807dd48d28 RCX: dffffc0000000000
RDX: 0000000080010001 RSI: 0000000000000000 RDI: 188fb626096661c8
RBP: 188fb6268818a710 R08: ffffffff88b6755a R09: 0000000000000003
R10: ffffffffffffffff R11: dffffc0000000001 R12: 0000000000000000
R13: 1ffff11003f2bd95 R14: dffffc0000000000 R15: ffff88807dd48d10
FS: 0000000000000000(0000) GS:ffff8880b9800000(0000) knlGS:0000000000000000
CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 000000002029d000 CR3: 0000000032163000 CR4: 00000000003506f0
DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000
DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400
Call Trace:
<NMI>
</NMI>
<IRQ>
__run_hrtimer kernel/time/hrtimer.c:1685 [inline]
__hrtimer_run_queues+0x5e5/0xe50 kernel/time/hrtimer.c:1749
hrtimer_interrupt+0x392/0x980 kernel/time/hrtimer.c:1811
local_apic_timer_interrupt arch/x86/kernel/apic/apic.c:1095 [inline]
__sysvec_apic_timer_interrupt+0x156/0x580 arch/x86/kernel/apic/apic.c:1112
sysvec_apic_timer_interrupt+0x8c/0xb0 arch/x86/kernel/apic/apic.c:1106
</IRQ>
<TASK>
asm_sysvec_apic_timer_interrupt+0x16/0x20 arch/x86/include/asm/idtentry.h:649
RIP: 0010:unwind_next_frame+0x7/0x2220 arch/x86/kernel/unwind_orc.c:423
Code: 41 5f c3 44 89 f1 80 e1 07 80 c1 03 38 c1 7c 95 4c 89 f7 e8 6b 1b a4 00 eb 8b 66 0f 1f 84 00 00 00 00 00 55 41 57 41 56 41 55 <41> 54 53 48 81 ec a8 00 00 00 48 89 fb 49 be 00 00 00 00 00 fc ff
RSP: 0018:ffffc900051bf498 EFLAGS: 00000202
RAX: 0000000000000001 RBX: ffffc900051bf4c0 RCX: ffffffff8fb13000
RDX: dffffc0000000000 RSI: ffffffff810058ef RDI: ffffc900051bf4c0
RBP: ffffc900051bf550 R08: 000000000000000e R09: ffffc900051bf5b0
R10: 0000000000000000 R11: dffffc0000000001 R12: ffff888073dd3b80
R13: ffffffff8177e6c0 R14: ffffc900051bf5a0 R15: 0000000000000000
arch_stack_walk+0x10d/0x140 arch/x86/kernel/stacktrace.c:25
stack_trace_save+0x113/0x1c0 kernel/stacktrace.c:122
kasan_save_stack mm/kasan/common.c:45 [inline]
kasan_set_track+0x4b/0x70 mm/kasan/common.c:52
kasan_save_free_info+0x27/0x40 mm/kasan/generic.c:516
____kasan_slab_free+0xd6/0x120 mm/kasan/common.c:236
kasan_slab_free include/linux/kasan.h:177 [inline]
slab_free_hook mm/slub.c:1724 [inline]
slab_free_freelist_hook mm/slub.c:1750 [inline]
slab_free mm/slub.c:3661 [inline]
__kmem_cache_free+0x25c/0x3c0 mm/slub.c:3674
kernfs_put+0x1c1/0x4a0 fs/kernfs/dir.c:553
kernfs_remove_by_name_ns+0xdc/0x150 fs/kernfs/dir.c:1639
kernfs_remove_by_name include/linux/kernfs.h:618 [inline]
remove_files fs/sysfs/group.c:28 [inline]
sysfs_remove_group+0xfa/0x2a0 fs/sysfs/group.c:288
sysfs_remove_groups+0x50/0xa0 fs/sysfs/group.c:312
destroy_port drivers/infiniband/core/sysfs.c:1285 [inline]
ib_free_port_attrs+0x266/0x3d0 drivers/infiniband/core/sysfs.c:1415
remove_one_compat_dev drivers/infiniband/core/device.c:1002 [inline]
rdma_dev_exit_net+0x1ef/0x350 drivers/infiniband/core/device.c:1140
ops_exit_list net/core/net_namespace.c:169 [inline]
cleanup_net+0x6ce/0xb60 net/core/net_namespace.c:601
process_one_work+0x8aa/0x11f0 kernel/workqueue.c:2292
worker_thread+0xa5f/0x1210 kernel/workqueue.c:2439
kthread+0x26e/0x300 kernel/kthread.c:376
ret_from_fork+0x1f/0x30 arch/x86/entry/entry_64.S:306
</TASK>


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[syzbot]

Auto-closing this bug as obsolete.
Crashes did not happen for a while, no reproducer and no activity.