Re: [linux-safety] [PATCH] usb: host: ehci-sched: add comment about find_tt() not returning error

From: Lukas Bulwahn
Date: Tue Oct 13 2020 - 04:02:56 EST




On Tue, 13 Oct 2020, Greg Kroah-Hartman wrote:

> On Tue, Oct 13, 2020 at 09:16:27AM +0200, Lukas Bulwahn wrote:
> > Some others actually believe that the use of static analysis tools
> > increase software quality and ONLY IF a static analysis tool is used, a
> > specific level of software quality is achieved and they want to prove
> > that the software reaches a certain level that way. (I do not
> > understand that argument but some have been repeating it quite often
> > around me. This argument seems to come from a specific interpretation of
> > safety standards that claim to have methods to predict the absense of
> > bugs up to a certain confidence.)
>
> So do those others also audit the static analysis tools to ensure that
> they actually work as they "think" they do? If not, then their
> requirement is pretty pointless :)
>

Yes, they do audit the tools, but those audits and why that proves the
absense of a bug class is yet a completely different story...

> > I am doing it for the fun and learning about tools, and I am not such a
> > believer but those others would be forced by their beliefs until they
> > understand what static analysis tools and their janitors really already
> > contribute to the kernel development and where the real gaps might be.
> >
> > I hope that helps to get a bit of the motivation. Consider us
> > kernel newbies :)
>
> Watch out, sending patches to subsystems to "fix" issues that really
> are not real problems is a sure way to get your patches rejected and
> make maintainers grumpy.
>
> I recommend starting out with code that we all "know" needs help, in
> drivers/staging/ for stuff like this, so you can learn the process
> better, as well as start to understand the limitations of your tools
> better.
>
> good luck!
>

Thanks for the advice. We will need to learn about the limitations and
what is worth a patch and what is not and we will need luck on the way
learning that.

Lukas