Subject: Re: [PATCH bpf] xdp: Handle device unregister for devmap_hash map type

From: Toke Høiland-Jørgensen <[email-masked]>
Date: Fri, 18 Oct 2019 12:31:11 +0200

Andrii Nakryiko <[email-masked]> writes:

> On Wed, Oct 16, 2019 at 9:07 AM Toke Høiland-Jørgensen <[email-masked]> wrote:
>>
>> It seems I forgot to add handling of devmap_hash type maps to the device
>> unregister hook for devmaps. This omission causes devices to not be
>> properly released, which causes hangs.
>>
>> Fix this by adding the missing handler.
>>
>> Fixes: 6f9d451ab1a3 ("xdp: Add devmap_hash map type for looking up devices by hashed index")
>> Reported-by: Tetsuo Handa <[email-masked]>
>> Signed-off-by: Toke Høiland-Jørgensen <[email-masked]>
>> ---
>>  kernel/bpf/devmap.c | 34 ++++++++++++++++++++++++++++++++++
>>  1 file changed, 34 insertions(+)
>>
>
> [...]
>
>> +
>> +               while (dev) {
>> +                       odev = (netdev == dev->dev) ? dev : NULL;
>> +                       dev = hlist_entry_safe(rcu_dereference_raw(hlist_next_rcu(&dev->index_hlist)),
>
> Please run scripts/checkpatch.pl, this looks like a rather long line.

That was a deliberate departure from the usual line length, actually. I
don't think it helps readability to split that into three lines just to
adhere to a strict line length requirement...

-Toke