On 2023/08/30 20:26, Hillf Danton wrote:
>> <4>[ 399.014716] Call trace:
>> <4>[ 399.015702] percpu_counter_add_batch+0x28/0xd0
>> <4>[ 399.016399] dst_destroy+0x44/0x1e4
>> <4>[ 399.016681] dst_destroy_rcu+0x14/0x20
>> <4>[ 399.017009] rcu_core+0x2d0/0x5e0
>> <4>[ 399.017311] rcu_core_si+0x10/0x1c
>> <4>[ 399.017609] __do_softirq+0xd4/0x23c
>> <4>[ 399.017991] ____do_softirq+0x10/0x1c
>> <4>[ 399.018320] call_on_irq_stack+0x24/0x4c
>> <4>[ 399.018723] do_softirq_own_stack+0x1c/0x28
>> <4>[ 399.022639] __irq_exit_rcu+0x6c/0xcc
>> <4>[ 399.023434] irq_exit_rcu+0x10/0x1c
>> <4>[ 399.023962] el1_interrupt+0x8c/0xc0
>> <4>[ 399.024810] el1h_64_irq_handler+0x18/0x24
>> <4>[ 399.025324] el1h_64_irq+0x64/0x68
>> <4>[ 399.025612] _raw_spin_lock_bh+0x0/0x6c
>> <4>[ 399.026102] cleanup_net+0x280/0x45c
>> <4>[ 399.026403] process_one_work+0x1d4/0x310
>> <4>[ 399.027140] worker_thread+0x248/0x470
>> <4>[ 399.027621] kthread+0xfc/0x184
>> <4>[ 399.028068] ret_from_fork+0x10/0x20
>
> static void cleanup_net(struct work_struct *work)
> {
> ...
>
> synchronize_rcu();
>
> /* Run all of the network namespace exit methods */
> list_for_each_entry_reverse(ops, &pernet_list, list)
> ops_exit_list(ops, &net_exit_list);
> ...
>
> Why did the RCU sync above fail to work in this report, Eric?
Why do you assume that synchronize_rcu() failed to work?
The trace merely says that an interrupt handler ran somewhere from
cleanup_net(), and something went wrong inside dst_destroy().
Please decode the trace into filename:line format (like syzbot reports)
using scripts/faddr2line tool, in order to find the exact location.