Re: [PATCH 2/2] powerpc/lib: Implement UACCESS_FLUSHCACHE API

[Oliver <oohall@gmail.com>]

On Thu, Oct 19, 2017 at 10:14 PM, Christophe LEROY
<christophe.leroy@c-s.fr> wrote:
>
>
> Le 19/10/2017 =C3=A0 09:13, Oliver O'Halloran a =C3=A9crit :
>>
>> Implement the architecture specific portitions of the UACCESS_FLUSHCACHE
>> API. This provides functions for the copy_user_flushcache iterator that
>> ensure that when the copy is finished the destination buffer contains
>> a copy of the original and that the destination buffer is clean in the
>> processor caches.
>>
>> Signed-off-by: Oliver O'Halloran <oohall@gmail.com>
>> ---
>>   arch/powerpc/Kconfig               |  1 +
>>   arch/powerpc/include/asm/string.h  |  2 ++
>>   arch/powerpc/include/asm/uaccess.h |  5 +++++
>>   arch/powerpc/lib/pmem.c            | 33
>> +++++++++++++++++++++++++++++++++
>>   4 files changed, 41 insertions(+)
>>
>> diff --git a/arch/powerpc/Kconfig b/arch/powerpc/Kconfig
>> index 0996add8a572..09a207468f8b 100644
>> --- a/arch/powerpc/Kconfig
>> +++ b/arch/powerpc/Kconfig
>> @@ -142,6 +142,7 @@ config PPC
>>         select ARCH_HAS_SCALED_CPUTIME          if
>> VIRT_CPU_ACCOUNTING_NATIVE
>>         select ARCH_HAS_SG_CHAIN
>>         select ARCH_HAS_TICK_BROADCAST          if
>> GENERIC_CLOCKEVENTS_BROADCAST
>> +       select ARCH_HAS_UACCESS_FLUSHCACHE      if PPC64
>
>
> Same as previous patch in the serye, why restrict it to PPC64 ?

It's not highmem aware and as I said  in the previous reply I'd rather
not enable it on platforms where no one has tested it.


Oliver