Re: [PATCH V14] mm/debug: Add tests validating architecture page table helpers

Christophe Leroy
2020-03-05T05:43:37Z

Le 05/03/2020 à 01:54, Anshuman Khandual a écrit :
>
>
> On 03/04/2020 04:59 PM, Qian Cai wrote:
>>
>>
>>> On Mar 4, 2020, at 1:49 AM, Christophe Leroy <christophe.leroy@c-s.fr> wrote:
>>>
>>> AFAIU, you are not taking an interrupt here. You are stuck in the pte_update(), most likely due to nested locks. Try with LOCKDEP ?
>>
>> Not exactly sure what did you mean here, but the kernel has all lockdep enabled and did not flag anything here.
>
> As the patch has been dropped from Linux next (next-20200304) perhaps in
> order to fold back the __pa_symbol() fix [1], so I am planning to respin
> the original patch once more as V15 while adding Qian's signed off by for
> the powerpc part. For now lets enable radix MMU ppc64 along with existing
> ppc32. As PPC_RADIX_MMU depends on PPC_BOOK3S_64, the following change
> should be good enough ?

I don't think so, even if you have the Radix MMU compiled in, hash MMU
is used when Radix is not available or disabled. So until the Hash MMU
problem is fixed, you cannot enable it by default.

Christophe