Re: Arm64 crash while reading memory sysfs

[Anshuman Khandual]

On 5/28/21 10:43 AM, Mike Rapoport wrote:
> On Thu, May 27, 2021 at 03:56:44PM -0700, Andrew Morton wrote:
>> On Thu, 27 May 2021 18:50:48 +0100 Catalin Marinas <catalin.marinas@xxxxxxx> wrote:
>>
>>>> Can you please try Anshuman's patch "arm64/mm: Drop HAVE_ARCH_PFN_VALID":
>>>>
>>>> https://lore.kernel.org/lkml/1621947349-25421-1-git-send-email-anshuman.khandual@xxxxxxx
>>>>
>>>> It seems to me that the check for memblock_is_memory() in
>>>> arm64::pfn_valid() is what makes init_unavailable_range() to bail out for
>>>> section parts that are not actually populated and then we have
>>>> VM_BUG_ON_PAGE(PagePoisoned(p)) for these pages.
>>>
>>> I acked Anshuman's patch, I think they all need to go in together.
>>
>> That's neat.   Specifically which patches are we referring to here?
> 
> arm64: drop pfn_valid_within() and simplify pfn_valid():
> https://lore.kernel.org/lkml/20210511100550.28178-5-rppt@xxxxxxxxxx
> 
> arm64/mm: Drop HAVE_ARCH_PFN_VALID:
> https://lore.kernel.org/lkml/1621947349-25421-1-git-send-email-anshuman.khandual@xxxxxxx

I dont see the above patch (which drops HAVE_ARCH_PFN_VALID on arm64) on linux-next
i.e. next-20210607. I might have missed some earlier context here but do not we want
to fallback on generic pfn_valid() after Mike's series ?