Re: [GIT PULL] Please pull powerpc/linux.git powerpc-5.8-1 tag

[Michael Ellerman <mpe@ellerman.id.au>]

Linus Torvalds <torvalds@linux-foundation.org> writes:
> On Fri, Jun 5, 2020 at 9:38 AM Michael Ellerman <mpe@ellerman.id.au> wrote:
>>
>> I've pushed the result of my resolution of the conflicts to the powerpc/merge
>> branch, if you want to look at that, though I've also tried to describe it in
>> full below.
>
> I ended up doing the machine_check_exception() differently, because I
> felt the code itself was done wrong and I wanted to add a note about
> that.
>
> Having the same function have completely different semantics depending
> on a platform issue is just fundamentally wrong, and makes not just
> for fragile code, but also means that you can't do single image
> kernels.

Yeah I agree it's not that nicely structured.

In this case CONFIG_PPC_BOOK3S_64 is one of our top-level compile time
switches anyway, so the single image thing at least isn't a concern.

> It should be two different functions, possibly just
>
>    non_nmi_fn() { ... }
>
>    nmi_fn() { nmi_enter(); non_nmi_fn(); nmi_exit(); }
>
> and now you don't have odd rules for the same function that depends on
> how the platform happens to call it.

Agreed.

> I didn't do the above. I did something that looked like the old code,
> but had a comment. Oh well.

Thanks, we can restructure it later.

> But thanks for describing the merge, I'd have missed the place where
> there was a new use of pgd_oiffset().

Yeah I missed it to begin with :}

> ..and then when I actually compared whether I otherwise got the same
> result as you, I realized that this all depends on the module tree.
>
> I'll go merge that first, and then re-do this all. Oh well.

Darn it. I figured you'd have merged that by the time you saw my pull,
will mention anything similar in future.

cheers