Re: regression in iwlwifi: page fault in iwl_dbg_tlv_alloc_region() (commit ba8f6f4ae254)

From: Takashi Iwai
Date: Tue Jan 12 2021 - 11:00:12 EST


On Tue, 12 Jan 2021 16:46:21 +0100,
Kalle Valo wrote:
>
> Takashi Iwai <tiwai@xxxxxxx> writes:
>
> > On Tue, 12 Jan 2021 13:45:33 +0100,
> > Kalle Valo wrote:
> >>
> >> Takashi Iwai <tiwai@xxxxxxx> writes:
> >>
> >> > On Tue, 12 Jan 2021 12:33:14 +0100,
> >> > Kalle Valo wrote:
> >> >>
> >> >> (adding luca)
> >> >>
> >> >> Michal Kubecek <mkubecek@xxxxxxx> writes:
> >> >>
> >> >> > FYI, there is a regression in iwlwifi driver caused by commit
> >> >> > ba8f6f4ae254 ("iwlwifi: dbg: add dumping special device memory")
> >> >> > reported at
> >> >> >
> >> >> > https://bugzilla.kernel.org/show_bug.cgi?id=210733
> >> >> > https://bugzilla.suse.com/show_bug.cgi?id=1180344
> >> >> >
> >> >> > The problem seems to be an attempt to write terminating null character
> >> >> > into a string which may be read only. There is also a proposed fix.
> >> >>
> >> >> Can someone submit a proper patch, please? See instructions below how to
> >> >> submit.
> >> >>
> >> >> And please add Fixes tag to the commit log:
> >> >>
> >> >> Fixes: ba8f6f4ae254 ("iwlwifi: dbg: add dumping special device memory")
> >> >
> >> > OK, I'll do it for my own
> >>
> >> Thanks.
> >>
> >> > but really I hoped that someone would have reacted on the bugzilla
> >> > report before the official patch submission. So far no one from the
> >> > upstream devs showed interest in the bug at all, unfortunately.
> >>
> >> Bugzilla is problematic as I don't know if anyone tracks it actively, at
> >> least I don't have time for that. I recommend reporting all wireless
> >> issues to mailing lists to make sure everyone see it.
> >
> > I share your feeling as a subsystem maintainer, but at the same time,
> > I see it's a big problem if the whole bugzilla reports are just
> > silently ignored. If it's a void, shouldn't we rather shut it down?
>
> I'm all for shutting down bugzilla.kernel.org as silent bug reports are
> frustrating the users. But I don't know what others would think about
> that, maybe some subsystems use it actively?

Yes, I'm still checking bugzilla.kernel.org for sound bug reports.
Not always promptly reacting like the distro bugzilla, but it's
regularly scanned and covered in the best effort basis.

Graphics people already moved out of bugzilla to gitlab Issues in
their own gitlab.freedesktop.org. Not sure about others.

> At least there should be a big warning for wireless bugs.

Maybe we can ask Konstantin about that at least for wireless
components?

> > And, although a mailing list is fine to report via only some texts or
> > some patches, it's not suitable to attach large logs or such, which is
> > often essential for debugging. Thanks to lore, the archivability is
> > no longer a problem with ML recently, but the lack of data assignment
> > is another problem, IMO.
>
> Sure, I fully agree on the benefits of a bug tracker. The issue here is
> the lack of people managing bug reports, not the tool.

Yeah, it's not only about wireless but true in general: handling bug
reports is a tough task and often annoying. Moreover, everyone of
course wants to believe that their driver is bug free :)


Takashi