Re: [PATCH v8 00/14] Convert powerpc to default topdown mmap layout (v8)

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

Christophe Leroy <christophe.leroy@csgroup.eu> writes:
> Hi Michael, hi Andrew
>
> Le 09/03/2022 à 18:44, Christophe Leroy a écrit :
>> Rebased on top of powerpc/next branch
>> 
>> This series converts powerpc to default topdown mmap layout.
>> 
>> powerpc requires its own arch_get_unmapped_area() only when
>> slices are needed, which is only for book3s/64. First part of
>> the series moves slices into book3s/64 specific directories
>> and cleans up other subarchitectures.
>> 
>> Last part converts to default topdown mmap layout.
>> 
>> A small modification is done to core mm to allow
>> powerpc to still provide its own arch_randomize_brk()
>> 
>> Another modification is done to core mm to allow powerpc
>> to use generic versions of get_unmapped_area functions for Radix
>> while still providing its own implementation for Hash, the
>> selection between Radix and Hash being doing at runtime.
>> 
>> Last modification to core mm is to give len and flags to
>> arch_get_mmap_end().
>> 
>> Signed-off-by: Christophe Leroy <christophe.leroy@csgroup.eu>
>
> What's the way forward for this series ?

It's a bit of a tricky series.

> Patches 1 has been merged in PCI tree.

That's fine I guess, it can go into v5.18, it's only patch 14 that
depends on it.

> Patches 2 to 5 are core mm, patch 5 being a fix.

A fix for arm64 even, just to complicate things :)

> Then patches 6 to 14 are powerpc.

With a fairly sizable diffstat, ie. likely to conflict.

> What will be the merge strategy ? I guess it's a bit late to get it 
> through powerpc tree, so I was just wondering whether we could get 
> patches 2 to 5 in mm this cycle, and the powerpc ones next cycle ?

Yeah I didn't pick it up because the mm changes don't have many acks and
I'm always nervous about carrying generic mm changes.

It would be my preference if Andrew could take 2-5 through mm for v5.18,
but it is quite late, so I'm not sure how he will feel about that.

Arguably 2, 3, 4 do very little. It's only patch 5 that has much effect,
and it has a reviewed-by from Catalin at least.

cheers