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From:   Michael Ellerman <mpe@ellerman.id.au>
To:     Linus Torvalds <torvalds@linux-foundation.org>
Cc:     Julia Lawall <Julia.Lawall@inria.fr>,
        Alexey Kardashevskiy <aik@ozlabs.ru>,
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Subject: Re: [GIT PULL] Please pull powerpc/linux.git powerpc-5.18-1 tag
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Date:   Mon, 28 Mar 2022 20:07:13 +1100
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Linus Torvalds <torvalds@linux-foundation.org> writes:
> On Fri, Mar 25, 2022 at 3:25 AM Michael Ellerman <mpe@ellerman.id.au> wrote:
>>
>> Livepatch support for 32-bit is probably the standout new feature, otherwise mostly just
>> lots of bits and pieces all over the board.
>
> Heh. I would have expected 32-bit ppc to be entirely legacy by now, so
> it's a bit surprising to see that being a standout feature.

We still get the odd bug report from people running mainline, or recent
stable kernels, on 32-bit.

And obviously Christophe has been doing lots of work on the Linux side,
so in that sense 32-bit is alive and well.

Having said that I don't think we'll see any new 32-bit CPU designs, so
the clock is slowly ticking.

> That said:
>
>> There's a series of commits cleaning up function descriptor handling,
>
> For some reason I also thought that powerpc had actually moved away
> from function descriptors, so I'm clearly not keeping up with the
> times.

No you're right, we have moved away from them, but not entirely.

Functions descriptors are still used for 64-bit big endian, but they're
not used for 64-bit little endian, or 32-bit.

cheers