[PATCH] ARM: mm: avoid attempting to flush the gate_vma with VIVT caches

[gilles.chanteperdrix@xenomai.org (Gilles Chanteperdrix)]

On 07/22/2012 05:09 PM, Will Deacon wrote:
> On Sun, Jul 22, 2012 at 02:26:03PM +0100, Gilles Chanteperdrix wrote:
>> On 07/22/2012 03:03 PM, Will Deacon wrote:
>>> On Sat, Jul 21, 2012 at 03:47:37PM +0100, Gilles Chanteperdrix wrote:
>>>> On 07/21/2012 04:40 PM, Gilles Chanteperdrix wrote:
>>>>> On 07/21/2012 04:35 PM, Will Deacon wrote:
>>>>>> It may be writable, but we never actually write to it after it has been
>>>>>> initialised so there's no need to worry about caching issues (the cache is
>>>>>> flushed in devicemaps_init).
>>>>>
>>>>> Except if CONFIG_TLS_REG_EMUL is enabled
>>>>
>>>> is disabled I mean.
>>>
>>> Well spotted! I disagree about the address being flushed though -- it looks
>>> to me like we flush from 0xffff0000 - 0xffff1000, which is what we want. Why
>>> do you think we're flushing from the linear mapping?
>>
>> I do not think we're flushing from the linear mapping, I believe the
>> address used by the elf_core_dump function (elf_core_dump -> kmap ->
>> page_address), to copy the page data to the core is the linear mapping
>> address, which is the reason why we need the flush at all.
> 
> Ok, good, sounds like we're singing the same tune at last. If you're happy
> with my proposed change to the original patch and Uros could re-test, then I
> think we're in business again.

It is OK for me.

-- 
                                                                Gilles.