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

Linus Torvalds [off-list ref] writes:

On Fri, Jun 5, 2020 at 9:38 AM Michael Ellerman [off-list ref] wrote:

quoted

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