Re: [Regression][BISECTED] kernel boot hang after 19898ce9cf8a ("wifi: iwlwifi: split 22000.c into multiple files")

From: Zhang, Rui
Date: Sun Jul 09 2023 - 09:27:45 EST


On Sat, 2023-07-08 at 16:17 +0200, Thorsten Leemhuis wrote:
> On 07.07.23 12:55, Linux regression tracking (Thorsten Leemhuis)
> wrote:
> > On 07.07.23 10:25, Zhang, Rui wrote:
> > >
> > > I run into a NULL pointer dereference and kernel boot hang after
> > > switching to latest upstream kernel, and git bisect shows that
> > > below
> > > commit is the first offending commit, and I have confirmed that
> > > commit
> > > 19898ce9cf8a has the issue while 19898ce9cf8a~1 does not.
> >
> > FWIW, this is the fourth such report about this that I'm aware of.
> >
> > The first is this one (with two affected users afaics):
> > https://bugzilla.kernel.org/show_bug.cgi?id=217622
> >
> > The second is this one:
> > https://lore.kernel.org/all/CAAJw_Zug6VCS5ZqTWaFSr9sd85k%3DtyPm9DEE%2BmV%3DAKoECZM%2BsQ@xxxxxxxxxxxxxx/
> >
> > The third:
> > https://lore.kernel.org/all/9274d9bd3d080a457649ff5addcc1726f08ef5b2.camel@xxxxxxxxxxx/
> >
> > And in the past few days two people from Fedora land talked to me
> > on IRC
> > with problems that in retrospective might be caused by this as
> > well.
>
> I got confirmation: one of those cases is also caused by 19898ce9cf8a
> But I write for a different reason:
>
> Larry (now CCed) looked at the culprit and spotted something that
> looked
> suspicious to him; he posted a patch and looks for testers:
> https://lore.kernel.org/all/0068af47-e475-7e8d-e476-c374e90dff5f@xxxxxxxxxxxx/

I applied this patch but the problem still exists.

thanks,
rui
>
> Ciao, Thorsten
>
> > This many reports about a problem at this stage of the cycle makes
> > me
> > suspect we'll see a lot more once -rc1 is out. That's why I raising
> > the
> > awareness of this. Sadly a simple revert of just this commit is not
> > possible. :-/
> >
> > Ciao, Thorsten
> >
> > > commit 19898ce9cf8a33e0ac35cb4c7f68de297cc93cb2 (refs/bisect/bad)
> > > Author:     Johannes Berg <johannes.berg@xxxxxxxxx>
> > > AuthorDate: Wed Jun 21 13:12:07 2023 +0300
> > > Commit:     Johannes Berg <johannes.berg@xxxxxxxxx>
> > > CommitDate: Wed Jun 21 14:07:00 2023 +0200
> > >
> > >     wifi: iwlwifi: split 22000.c into multiple files
> > >    
> > >     Split the configuration list in 22000.c into four new files,
> > >     per new device family, so we don't have this huge unusable
> > >     file. Yes, this duplicates a few small things, but that's
> > >     still much better than what we have now.
> > >    
> > >     Signed-off-by: Johannes Berg <johannes.berg@xxxxxxxxx>
> > >     Signed-off-by: Gregory Greenman <gregory.greenman@xxxxxxxxx>
> > >     Link:
> > > https://lore.kernel.org/r/20230621130443.7543603b2ee7.Ia8dd54216d341ef1ddc0531f2c9aa30d30536a5d@changeid
> > >     Signed-off-by: Johannes Berg <johannes.berg@xxxxxxxxx>
> > >
> > > I have some screenshots which show that RIP points to
> > > iwl_mem_free_skb,
> > > I can create a kernel bugzilla and attach the screenshots there
> > > if
> > > needed.
> > >
> > > BTW, lspci output of the wifi device and git bisect log attached.
> > >
> > > If any other information needed, please let me know.
> >
> > --
> > Everything you wanna know about Linux kernel regression tracking:
> > https://linux-regtracking.leemhuis.info/about/#tldr
> > That page also explains what to do if mails like this annoy you.
> >
> > P.S.: for regzbot
> >
> > #regzbot ^introduced 19898ce9cf8a
> > #regzbot dup-of:
> > https://lore.kernel.org/all/a5cdc7f8-b340-d372-2971-0d24b01de217@xxxxxxxxx/