Re: [GIT] Networking

From: Doug Ledford
Date: Mon Feb 24 2020 - 11:35:59 EST




> On Feb 24, 2020, at 11:33 AM, Leon Romanovsky <leon@xxxxxxxxxx> wrote:
>
> On Mon, Feb 24, 2020 at 01:47:32PM +0100, Greg KH wrote:
>> On Mon, Feb 24, 2020 at 11:01:09AM +0100, Geert Uytterhoeven wrote:
>>> Hi Linus,
>>>
>>> On Thu, Jun 25, 2015 at 1:38 AM Linus Torvalds
>>> <torvalds@xxxxxxxxxxxxxxxxxxxx> wrote:
>>>> On Wed, Jun 24, 2015 at 6:39 AM, David Miller <davem@xxxxxxxxxxxxx> wrote:
>>>>> git://git.kernel.org/pub/scm/linux/kernel/git/davem/net-next.git master
>>>>
>>>> On the *other* side of the same conflict, I find an even more
>>>> offensive commit, namely commit 4cd7c9479aff ("IB/mad: Add support for
>>>> additional MAD info to/from drivers") which adds a BUG_ON() for a
>>>> sanity check, rather than just returning -EINVAL or something sane
>>>> like that.
>>>>
>>>> I'm getting *real* tired of that BUG_ON() shit. I realize that
>>>> infiniband is a niche market, and those "commercial grade" niche
>>>> markets are more-than-used-to crap code and horrible hacks, but this
>>>> is still the kernel. We don't add random machine-killing debug checks
>>>> when it is *so* simple to just do
>>>>
>>>> if (WARN_ON_ONCE(..))
>>>> return -EINVAL;
>>>>
>>>> instead.
>>>
>>> And if we follow that advice, friendly Greg will respond with:
>>> "We really do not want WARN_ON() anywhere, as that causes systems with
>>> panic-on-warn to reboot."
>>> https://lore.kernel.org/lkml/20191121135743.GA552517@xxxxxxxxx/
>>
>> Yes, we should not have any WARN_ON calls for something that userspace
>> can trigger, because then syzbot will trigger it and we will get an
>> annoying report saying to fix it :)
>
> Impressive backlog :)
> Geert, you replied on original discussion from 2015.

Yeah, that threw me for a loop too ;-). Took several double takes on that one just to make sure none of the IB comments from Linus were related to anything current!

--
Doug Ledford <dledford@xxxxxxxxxx>
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