[syzbot] [net?] INFO: rcu detected stall in neigh_timer_handler (8)

[syzbot]

Hello,

syzbot found the following issue on:

HEAD commit: dc772f8237f9 Merge tag 'mm-hotfixes-stable-2024-06-07-15-2..
git tree: upstream
console output: https://syzkaller.appspot.com/x/log.txt?x=106a891c980000
kernel config: https://syzkaller.appspot.com/x/.config?x=333ebe38d43c42e2
dashboard link: https://syzkaller.appspot.com/bug?extid=5127feb52165f8ab165b
compiler: Debian clang version 15.0.6, GNU ld (GNU Binutils for Debian) 2.40
syz repro: https://syzkaller.appspot.com/x/repro.syz?x=17398dce980000
C reproducer: https://syzkaller.appspot.com/x/repro.c?x=112fa5ac980000

Downloadable assets:
disk image: https://storage.googleapis.com/syzbot-assets/8c3aeafbce8e/disk-dc772f82.raw.xz
vmlinux: https://storage.googleapis.com/syzbot-assets/484bb26b914c/vmlinux-dc772f82.xz
kernel image: https://storage.googleapis.com/syzbot-assets/d86a6cb060e3/bzImage-dc772f82.xz

The issue was bisected to:

commit a7f3813e589fd8e2834720829a47b5eb914a9afe
Author: Marcello Sylvester Bauer <sy...@sylv.io>
Date: Thu Apr 11 14:51:28 2024 +0000

usb: gadget: dummy_hcd: Switch to hrtimer transfer scheduler

bisection log: https://syzkaller.appspot.com/x/bisect.txt?x=1327637e980000
final oops: https://syzkaller.appspot.com/x/report.txt?x=10a7637e980000
console output: https://syzkaller.appspot.com/x/log.txt?x=1727637e980000

IMPORTANT: if you fix the issue, please add the following tag to the commit:
Reported-by: syzbot+5127fe...@syzkaller.appspotmail.com
Fixes: a7f3813e589f ("usb: gadget: dummy_hcd: Switch to hrtimer transfer scheduler")

rcu: INFO: rcu_preempt detected expedited stalls on CPUs/tasks: {
0-.... } 2647 jiffies s: 2905 root: 0x1/.
rcu: blocking rcu_node structures (internal RCU debug):

Sending NMI from CPU 1 to CPUs 0:
cdc_wdm 2-1:1.0: nonzero urb status received: -71
NMI backtrace for cpu 0
CPU: 0 PID: 785 Comm: kworker/0:2 Not tainted 6.10.0-rc2-syzkaller-00315-gdc772f8237f9 #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 04/02/2024
Workqueue: usb_hub_wq hub_event
RIP: 0010:io_serial_out+0x7e/0xc0 drivers/tty/serial/8250/8250_port.c:413
Code: fc 89 e9 41 d3 e7 48 83 c3 40 48 89 d8 48 c1 e8 03 42 80 3c 20 00 74 08 48 89 df e8 4c 8b bf fc 44 03 3b 44 89 f0 44 89 fa ee <5b> 41 5c 41 5e 41 5f 5d c3 cc cc cc cc 89 e9 80 e1 07 38 c1 7c a7
RSP: 0018:ffffc90000006ab0 EFLAGS: 00000002
RAX: 0000000000000030 RBX: ffffffff94ad1200 RCX: 0000000000000000
RDX: 00000000000003f8 RSI: 0000000000000000 RDI: 0000000000000020
RBP: 0000000000000000 R08: ffffffff853c5efb R09: 1ffff11003f54046
R10: dffffc0000000000 R11: ffffffff853c5eb0 R12: dffffc0000000000
R13: 0000000000000030 R14: 0000000000000030 R15: 00000000000003f8
FS: 0000000000000000(0000) GS:ffff8880b9400000(0000) knlGS:0000000000000000
CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 00007fa2f6c67850 CR3: 00000000202f6000 CR4: 00000000003506f0
DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000
DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400
Call Trace:
<NMI>
</NMI>
<IRQ>
serial8250_console_write+0x1212/0x1770 drivers/tty/serial/8250/8250_port.c:3393
console_emit_next_record kernel/printk/printk.c:2928 [inline]
console_flush_all+0x865/0xfd0 kernel/printk/printk.c:2994
console_unlock+0x13b/0x4d0 kernel/printk/printk.c:3063
vprintk_emit+0x5a6/0x770 kernel/printk/printk.c:2345
dev_vprintk_emit+0x2ae/0x330 drivers/base/core.c:4951
dev_printk_emit+0xdd/0x120 drivers/base/core.c:4962
_dev_err+0x122/0x170 drivers/base/core.c:5017
wdm_int_callback+0x41f/0xac0 drivers/usb/class/cdc-wdm.c:269
__usb_hcd_giveback_urb+0x373/0x530 drivers/usb/core/hcd.c:1648
dummy_timer+0x830/0x45d0 drivers/usb/gadget/udc/dummy_hcd.c:1987
__run_hrtimer kernel/time/hrtimer.c:1687 [inline]
__hrtimer_run_queues+0x59b/0xd50 kernel/time/hrtimer.c:1751
hrtimer_interrupt+0x396/0x990 kernel/time/hrtimer.c:1813
local_apic_timer_interrupt arch/x86/kernel/apic/apic.c:1032 [inline]
__sysvec_apic_timer_interrupt+0x110/0x3f0 arch/x86/kernel/apic/apic.c:1049
instr_sysvec_apic_timer_interrupt arch/x86/kernel/apic/apic.c:1043 [inline]
sysvec_apic_timer_interrupt+0x52/0xc0 arch/x86/kernel/apic/apic.c:1043
asm_sysvec_apic_timer_interrupt+0x1a/0x20 arch/x86/include/asm/idtentry.h:702
RIP: 0010:rtnl_notify+0x4f/0xc0 net/core/rtnetlink.c:755
Code: 00 00 00 00 00 fc ff df e8 9e 16 38 f8 48 81 c5 f0 02 00 00 48 89 e8 48 c1 e8 03 42 80 3c 30 00 74 08 48 89 ef e8 71 da 9d f8 <48> 8b 6d 00 48 85 db 74 27 e8 73 16 38 f8 48 83 c3 06 48 89 d8 48
RSP: 0018:ffffc90000007b10 EFLAGS: 00010246
RAX: 1ffffffff296c6be RBX: 0000000000000000 RCX: ffff88801fd83c00
RDX: 0000000000000101 RSI: ffffffff94b63300 RDI: ffff88802e1de8c0
RBP: ffffffff94b635f0 R08: 0000000000000000 R09: 0000000000000820
R10: 00004de500001511 R11: 0000000100000001 R12: 0000000000000003
R13: ffff88802e1de8c0 R14: dffffc0000000000 R15: 0000000000000000
neigh_update_notify net/core/neighbour.c:2675 [inline]
neigh_timer_handler+0xaae/0xfd0 net/core/neighbour.c:1166
call_timer_fn+0x18e/0x650 kernel/time/timer.c:1792
expire_timers kernel/time/timer.c:1843 [inline]
__run_timers kernel/time/timer.c:2417 [inline]
__run_timer_base+0x66a/0x8e0 kernel/time/timer.c:2428
run_timer_base kernel/time/timer.c:2437 [inline]
run_timer_softirq+0xb7/0x170 kernel/time/timer.c:2447
handle_softirqs+0x2c4/0x970 kernel/softirq.c:554
__do_softirq kernel/softirq.c:588 [inline]
invoke_softirq kernel/softirq.c:428 [inline]
__irq_exit_rcu+0xf4/0x1c0 kernel/softirq.c:637
irq_exit_rcu+0x9/0x30 kernel/softirq.c:649
instr_sysvec_apic_timer_interrupt arch/x86/kernel/apic/apic.c:1043 [inline]
sysvec_apic_timer_interrupt+0xa6/0xc0 arch/x86/kernel/apic/apic.c:1043
</IRQ>
<TASK>
asm_sysvec_apic_timer_interrupt+0x1a/0x20 arch/x86/include/asm/idtentry.h:702
RIP: 0010:console_flush_all+0xaad/0xfd0 kernel/printk/printk.c:3000
Code: ff ff e8 16 d0 1f 00 90 0f 0b 90 e9 d8 f8 ff ff e8 08 d0 1f 00 e8 83 31 10 0a 4d 85 f6 74 b6 e8 f9 cf 1f 00 fb 48 8b 44 24 70 <42> 0f b6 04 38 84 c0 48 8b 7c 24 30 0f 85 22 02 00 00 0f b6 1f 31
RSP: 0018:ffffc9000333f040 EFLAGS: 00000293
RAX: 1ffff92000667e54 RBX: 0000000000000000 RCX: ffff88801fd83c00
RDX: 0000000000000000 RSI: 0000000000000000 RDI: 0000000000000000
RBP: ffffc9000333f1f0 R08: ffffffff81765624 R09: 1ffffffff25f56ca
R10: dffffc0000000000 R11: fffffbfff25f56cb R12: ffffffff8eb225f8
R13: ffffffff8eb225a0 R14: 0000000000000200 R15: dffffc0000000000
console_unlock+0x13b/0x4d0 kernel/printk/printk.c:3063
vprintk_emit+0x5a6/0x770 kernel/printk/printk.c:2345
dev_vprintk_emit+0x2ae/0x330 drivers/base/core.c:4951
dev_printk_emit+0xdd/0x120 drivers/base/core.c:4962
_dev_info+0x122/0x170 drivers/base/core.c:5020
hub_port_init+0x7bf/0x2670 drivers/usb/core/hub.c:4950
hub_port_connect drivers/usb/core/hub.c:5450 [inline]
hub_port_connect_change drivers/usb/core/hub.c:5661 [inline]
port_event drivers/usb/core/hub.c:5821 [inline]
hub_event+0x295f/0x5150 drivers/usb/core/hub.c:5903
process_one_work kernel/workqueue.c:3231 [inline]
process_scheduled_works+0xa2c/0x1830 kernel/workqueue.c:3312
worker_thread+0x86d/0xd70 kernel/workqueue.c:3393
kthread+0x2f0/0x390 kernel/kthread.c:389
ret_from_fork+0x4b/0x80 arch/x86/kernel/process.c:147
ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:244
</TASK>
INFO: NMI handler (nmi_cpu_backtrace_handler) took too long to run: 4.241 msecs
cdc_wdm 2-1:1.0: wdm_int_callback - 0 bytes
cdc_wdm 2-1:1.0: nonzero urb status received: -71
cdc_wdm 2-1:1.0: wdm_int_callback - 0 bytes
cdc_wdm 2-1:1.0: nonzero urb status received: -71
cdc_wdm 2-1:1.0: wdm_int_callback - 0 bytes
cdc_wdm 2-1:1.0: nonzero urb status received: -71
cdc_wdm 2-1:1.0: wdm_int_callback - 0 bytes
cdc_wdm 2-1:1.0: nonzero urb status received: -71
cdc_wdm 2-1:1.0: wdm_int_callback - 0 bytes
cdc_wdm 2-1:1.0: wdm_int_callback - usb_submit_urb failed with result -19
cdc_wdm 2-1:1.0: nonzero urb status received: -71
cdc_wdm 2-1:1.0: wdm_int_callback - 0 bytes
cdc_wdm 2-1:1.0: nonzero urb status received: -71
cdc_wdm 2-1:1.0: wdm_int_callback - 0 bytes
cdc_wdm 2-1:1.0: nonzero urb status received: -71
cdc_wdm 2-1:1.0: wdm_int_callback - 0 bytes
cdc_wdm 2-1:1.0: nonzero urb status received: -71
cdc_wdm 2-1:1.0: wdm_int_callback - 0 bytes
cdc_wdm 2-1:1.0: nonzero urb status received: -71
cdc_wdm 2-1:1.0: wdm_int_callback - 0 bytes
cdc_wdm 2-1:1.0: nonzero urb status received: -71
cdc_wdm 2-1:1.0: wdm_int_callback - 0 bytes
cdc_wdm 2-1:1.0: nonzero urb status received: -71
cdc_wdm 2-1:1.0: wdm_int_callback - 0 bytes
cdc_wdm 2-1:1.0: wdm_int_callback - usb_submit_urb failed with result -19
cdc_wdm 4-1:1.0: nonzero urb status received: -71
cdc_wdm 4-1:1.0: wdm_int_callback - 0 bytes
cdc_wdm 4-1:1.0: nonzero urb status received: -71
cdc_wdm 4-1:1.0: wdm_int_callback - 0 bytes
cdc_wdm 4-1:1.0: nonzero urb status received: -71
cdc_wdm 4-1:1.0: wdm_int_callback - 0 bytes
cdc_wdm 4-1:1.0: nonzero urb status received: -71
cdc_wdm 4-1:1.0: wdm_int_callback - 0 bytes
cdc_wdm 4-1:1.0: wdm_int_callback - usb_submit_urb failed with result -19
cdc_wdm 2-1:1.0: nonzero urb status received: -71
cdc_wdm 2-1:1.0: wdm_int_callback - 0 bytes
cdc_wdm 2-1:1.0: nonzero urb status received: -71
cdc_wdm 2-1:1.0: wdm_int_callback - 0 bytes
cdc_wdm 2-1:1.0: nonzero urb status received: -71
cdc_wdm 2-1:1.0: wdm_int_callback - 0 bytes
cdc_wdm 2-1:1.0: nonzero urb status received: -71
cdc_wdm 2-1:1.0: wdm_int_callback - 0 bytes
cdc_wdm 2-1:1.0: wdm_int_callback - usb_submit_urb failed with result -19
cdc_wdm 4-1:1.0: nonzero urb status received: -71
cdc_wdm 4-1:1.0: wdm_int_callback - 0 bytes
cdc_wdm 4-1:1.0: nonzero urb status received: -71
cdc_wdm 4-1:1.0: wdm_int_callback - 0 bytes
cdc_wdm 4-1:1.0: wdm_int_callback - usb_submit_urb failed with result -19
cdc_wdm 5-1:1.0: nonzero urb status received: -71
cdc_wdm 5-1:1.0: wdm_int_callback - 0 bytes
cdc_wdm 5-1:1.0: nonzero urb status received: -71
cdc_wdm 5-1:1.0: wdm_int_callback - 0 bytes
cdc_wdm 5-1:1.0: nonzero urb status received: -71
cdc_wdm 5-1:1.0: wdm_int_callback - 0 bytes
cdc_wdm 5-1:1.0: nonzero urb status received: -71
cdc_wdm 5-1:1.0: wdm_int_callback - 0 bytes
cdc_wdm 5-1:1.0: nonzero urb status received: -71
cdc_wdm 5-1:1.0: wdm_int_callback - 0 bytes
cdc_wdm 5-1:1.0: nonzero urb status received: -71
cdc_wdm 5-1:1.0: wdm_int_callback - 0 bytes
cdc_wdm 5-1:1.0: wdm_int_callback - usb_submit_urb failed with result -19
cdc_wdm 4-1:1.0: nonzero urb status received: -71
cdc_wdm 4-1:1.0: wdm_int_callback - 0 bytes
cdc_wdm 4-1:1.0: nonzero urb status received: -71
cdc_wdm 4-1:1.0: wdm_int_callback - 0 bytes
cdc_wdm 4-1:1.0: nonzero urb status received: -71
cdc_wdm 4-1:1.0: wdm_int_callback - 0 bytes
cdc_wdm 4-1:1.0: nonzero urb status received: -71
cdc_wdm 4-1:1.0: wdm_int_callback - 0 bytes
cdc_wdm 4-1:1.0: nonzero urb status received: -71
cdc_wdm 4-1:1.0: wdm_int_callback - 0 bytes
cdc_wdm 4-1:1.0: nonzero urb status received: -71
cdc_wdm 4-1:1.0: wdm_int_callback - 0 bytes
cdc_wdm 4-1:1.0: wdm_int_callback - usb_submit_urb failed with result -19
cdc_wdm 2-1:1.0: nonzero urb status received: -71
cdc_wdm 2-1:1.0: wdm_int_callback - 0 bytes
cdc_wdm 2-1:1.0: nonzero urb status received: -71
cdc_wdm 2-1:1.0: wdm_int_callback - 0 bytes
cdc_wdm 2-1:1.0: wdm_int_callback - usb_submit_urb failed with result -19
cdc_wdm 4-1:1.0: nonzero urb status received: -71
cdc_wdm 4-1:1.0: wdm_int_callback - 0 bytes
cdc_wdm 4-1:1.0: wdm_int_callback - usb_submit_urb failed with result -19
cdc_wdm 2-1:1.0: nonzero urb status received: -71
cdc_wdm 2-1:1.0: wdm_int_callback - 0 bytes
cdc_wdm 2-1:1.0: nonzero urb status received: -71
cdc_wdm 2-1:1.0: wdm_int_callback - 0 bytes
cdc_wdm 2-1:1.0: nonzero urb status received: -71
cdc_wdm 2-1:1.0: wdm_int_callback - 0 bytes
cdc_wdm 2-1:1.0: wdm_int_callback - usb_submit_urb failed with result -19
cdc_wdm 5-1:1.0: nonzero urb status received: -71
cdc_wdm 5-1:1.0: wdm_int_callback - 0 bytes
cdc_wdm 5-1:1.0: nonzero urb status received: -71
cdc_wdm 5-1:1.0: wdm_int_callback - 0 bytes
cdc_wdm 5-1:1.0: nonzero urb status received: -71
cdc_wdm 5-1:1.0: wdm_int_callback - 0 bytes
cdc_wdm 5-1:1.0: nonzero urb status received: -71
cdc_wdm 5-1:1.0: wdm_int_callback - 0 bytes
cdc_wdm 5-1:1.0: nonzero urb status received: -71
cdc_wdm 5-1:1.0: wdm_int_callback - 0 bytes
cdc_wdm 5-1:1.0: wdm_int_callback - usb_submit_urb failed with result -19
cdc_wdm 2-1:1.0: nonzero urb status received: -71
cdc_wdm 2-1:1.0: wdm_int_callback - 0 bytes
cdc_wdm 2-1:1.0: nonzero urb status received: -71
cdc_wdm 2-1:1.0: wdm_int_callback - 0 bytes
cdc_wdm 2-1:1.0: wdm_int_callback - usb_submit_urb failed with result -19
cdc_wdm 1-1:1.0: nonzero urb status received: -71
cdc_wdm 1-1:1.0: wdm_int_callback - 0 bytes
cdc_wdm 1-1:1.0: nonzero urb status received: -71
cdc_wdm 1-1:1.0: wdm_int_callback - 0 bytes
cdc_wdm 1-1:1.0: nonzero urb status received: -71
cdc_wdm 1-1:1.0: wdm_int_callback - 0 bytes
cdc_wdm 1-1:1.0: nonzero urb status received: -71
cdc_wdm 1-1:1.0: wdm_int_callback - 0 bytes
cdc_wdm 1-1:1.0: nonzero urb status received: -71
cdc_wdm 1-1:1.0: wdm_int_callback - 0 bytes
cdc_wdm 1-1:1.0: wdm_int_callback - usb_submit_urb failed with result -19
cdc_wdm 4-1:1.0: nonzero urb status received: -71
cdc_wdm 4-1:1.0: wdm_int_callback - 0 bytes
cdc_wdm 4-1:1.0: nonzero urb status received: -71
cdc_wdm 4-1:1.0: wdm_int_callback - 0 bytes
cdc_wdm 4-1:1.0: nonzero urb status received: -71
cdc_wdm 4-1:1.0: wdm_int_callback - 0 bytes
cdc_wdm 4-1:1.0: nonzero urb status received: -71
cdc_wdm 4-1:1.0: wdm_int_callback - 0 bytes
cdc_wdm 4-1:1.0: nonzero urb status received: -71
cdc_wdm 4-1:1.0: wdm_int_callback - 0 bytes
cdc_wdm 4-1:1.0: nonzero urb status received: -71
cdc_wdm 4-1:1.0: wdm_int_callback - 0 bytes
cdc_wdm 4-1:1.0: wdm_int_callback - usb_submit_urb failed with result -19
cdc_wdm 3-1:1.0: nonzero urb status received: -71
cdc_wdm 3-1:1.0: wdm_int_callback - 0 bytes
cdc_wdm 3-1:1.0: nonzero urb status received: -71
cdc_wdm 3-1:1.0: wdm_int_callback - 0 bytes
cdc_wdm 3-1:1.0: nonzero urb status received: -71
cdc_wdm 3-1:1.0: wdm_int_callback - 0 bytes
cdc_wdm 3-1:1.0: nonzero urb status received: -71
cdc_wdm 3-1:1.0: wdm_int_callback - 0 bytes
cdc_wdm 3-1:1.0: nonzero urb status received: -71
cdc_wdm 3-1:1.0: wdm_int_callback - 0 bytes
cdc_wdm 3-1:1.0: nonzero urb status received: -71
cdc_wdm 3-1:1.0: wdm_int_callback - 0 bytes
cdc_wdm 3-1:1.0: nonzero urb status received: -71
cdc_wdm 3-1:1.0: wdm_int_callback - 0 bytes
cdc_wdm 3-1:1.0: nonzero urb status received: -71
cdc_wdm 3-1:1.0: wdm_int_callback - 0 bytes
cdc_wdm 3-1:1.0: nonzero urb status received: -71
cdc_wdm 3-1:1.0: wdm_int_callback - 0 bytes
cdc_wdm 3-1:1.0: nonzero urb status received: -71
cdc_wdm 3-1:1.0: wdm_int_callback - 0 bytes
cdc_wdm 3-1:1.0: nonzero urb status received: -71
cdc_wdm 3-1:1.0: wdm_int_callback - 0 bytes
cdc_wdm 3-1:1.0: nonzero urb status received: -71
cdc_wdm 3-1:1.0: wdm_int_callback - 0 bytes
cdc_wdm 3-1:1.0: wdm_int_callback - usb_submit_urb failed with result -19
cdc_wdm 4-1:1.0: nonzero urb status received: -71
cdc_wdm 4-1:1.0: wdm_int_callback - 0 bytes
cdc_wdm 4-1:1.0: nonzero urb status received: -71
cdc_wdm 4-1:1.0: wdm_int_callback - 0 bytes
cdc_wdm 4-1:1.0: nonzero urb status received: -71
cdc_wdm 4-1:1.0: wdm_int_callback - 0 bytes
cdc_wdm 4-1:1.0: nonzero urb status received: -71
cdc_wdm 4-1:1.0: wdm_int_callback - 0 bytes
cdc_wdm 4-1:1.0: nonzero urb status received: -71
cdc_wdm 4-1:1.0: wdm_int_callback - 0 bytes
cdc_wdm 4-1:1.0: wdm_int_callback - usb_submit_urb failed with result -19


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