Vexpress TC2 no longer booting on v4.12-rc1

[Mathieu Poirier]

On 2 June 2017 at 16:24, Russell King - ARM Linux <linux at armlinux.org.uk> wrote:
> On Fri, Jun 02, 2017 at 04:16:59PM -0600, Mathieu Poirier wrote:
>> Good afternoon Russell and friends,
>>
>> I noticed that my vexpress-TC2 platform stopped booting when moving to
>> kernel v4.12-rc1 (same with -rc2 and 3).  The last time things worked
>> properly was on v4.11.  I did a bisect between v4.11 and v4.12-rc1 and
>> ended up on [1], hence this email.
>>
>> Since CONFIG_ARM_VIRT_EXT is selected by  default I removed the
>> "#ifdef CONFIG_ARM_VIRT_EXT" section in the last hunk of the patch and
>> the system sprung up to life again.
>
> Hmm, this doesn't make much sense.  The code in last hunk of the patch
> you refer to should only get run during system shutdown, not during
> system boot, so I think something else is going on...
>
> Please could you test again, this time rather than removing the #ifdef,
> add two "mov r0, r0" there?  (So replacing the two instructions that
> removing the ifdef would have exposed.)

That works - by replacing the original code with a couple of "mov r0,
r0" the system is able to boot again.

>
> Thanks.
>
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