Re: Unable to handle kernel NULL pointer dereference at virtual address 0000000000000008

[Naresh Kamboju]

Hi Saravana,

On Tue, 23 Aug 2022 at 02:09, Saravana Kannan <saravanak@xxxxxxxxxx> wrote:
>
> On Mon, Aug 22, 2022 at 7:00 AM Naresh Kamboju
> <naresh.kamboju@xxxxxxxxxx> wrote:
> >
> > The arm64 Qualcomm db410c device boot failed intermittently on
> > Linux next-20220822 and Linux mainline 6.0.0-rc1.
> >
> > Reported-by: Linux Kernel Functional Testing <lkft@xxxxxxxxxx>
> >
> > [    0.000000] Linux version 6.0.0-rc1 (tuxmake@tuxmake)
> > (aarch64-linux-gnu-gcc (Debian 11.3.0-3) 11.3.0, GNU ld (GNU Binutils
> > for Debian) 2.38.90.20220713) #1 SMP PREEMPT @1661110347
> > [    0.000000] Machine model: Qualcomm Technologies, Inc. APQ 8016 SBC
> > <trim>
> > [    3.609382] Loading compiled-in X.509 certificates
> > [    3.702306] Unable to handle kernel NULL pointer dereference at
> > virtual address 0000000000000008
> > [    3.702380] Mem abort info:

<trim>

> > [    3.771199] pc : pl011_probe+0x30/0x154
> > [    3.778480] l8: Bringing 0uV into 1750000-1750000uV
> > [    3.783073] lr : amba_probe+0x11c/0x1b0

<trim>

>
> Hi Naresh,
>
> Thanks for the report!
>
> These two patches together should fix the issue:
> https://lore.kernel.org/lkml/20220818172852.3548-1-isaacmanjarres@xxxxxxxxxx/
> https://lore.kernel.org/lkml/20220817184026.3468620-1-isaacmanjarres@xxxxxxxxxx/

Reported-by and Tested-by: Naresh Kamboju <naresh.kamboju@xxxxxxxxxx>
Reported-by and Tested-by: Linux Kernel Functional Testing <lkft@xxxxxxxxxx>


> Can you give them a shot please?

I have applied the above two patches on Linus master branch and built
and boot tested on db410c the boot is successful now [1].

> Also, in general, it'd be nice if you could report issues in the
> original thread of the patch causing issues. It would make it easier
> to keep track of all the issues.

When I bisect and confirm bad commits then I will reply to that thread.

[1] https://lkft.validation.linaro.org/scheduler/job/5423144#L2005

- Naresh