Re: [PATCH v7 bpf-next 0/9] introduce support for XDP programs in CPUMAP

Lorenzo Bianconi
2020-07-17T11:01:42Z

[-- Attachment #1: Type: text/plain, Size: 1584 bytes --]

[...]

> This started showing up with when running ./test_progs from recent
> bpf-next (bfdfa51702de). Any chance it is related?
>
> [ 2950.440613] =============================================
>
> [ 3073.281578] INFO: task cpumap/0/map:26:536 blocked for more than 860 seconds.
> [ 3073.285492] Tainted: G W 5.8.0-rc4-01471-g15d51f3a516b #814
> [ 3073.289177] "echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message.
> [ 3073.293021] cpumap/0/map:26 D 0 536 2 0x00004000
> [ 3073.295755] Call Trace:
> [ 3073.297143] __schedule+0x5ad/0xf10
> [ 3073.299032] ? pci_mmcfg_check_reserved+0xd0/0xd0
> [ 3073.301416] ? static_obj+0x31/0x80
> [ 3073.303277] ? mark_held_locks+0x24/0x90
> [ 3073.305313] ? cpu_map_update_elem+0x6d0/0x6d0
> [ 3073.307544] schedule+0x6f/0x160
> [ 3073.309282] schedule_preempt_disabled+0x14/0x20
> [ 3073.311593] kthread+0x175/0x240
> [ 3073.313299] ? kthread_create_on_node+0xd0/0xd0
> [ 3073.315106] ret_from_fork+0x1f/0x30
> [ 3073.316365]
> Showing all locks held in the system:
> [ 3073.318423] 1 lock held by khungtaskd/33:
> [ 3073.319642] #0: ffffffff82d246a0 (rcu_read_lock){....}-{1:2}, at: debug_show_all_locks+0x28/0x1c3
>
> [ 3073.322249] =============================================

Hi Jakub,

can you please provide more info? can you please identify the test that trigger
the issue? I run test_progs with bpf-next master branch and it works fine for me.
I run the tests in a vm with 4 vcpus and 4G of memory.

Regards,
Lorenzo

[-- Attachment #2: signature.asc --]
[-- Type: application/pgp-signature, Size: 228 bytes --]