Re: [PATCH v2 0/2] x86/mm: support memory-failure on 32-bits with SPARSEMEM

David Hildenbrand (Red Hat)
2025-11-17T13:03:54Z

On 17.11.25 03:09, Xie Yuanbin wrote:
> On Wed, 5 Nov 2025 17:05:36 +0800, Xie Yuanbin wrote:
>> On Wed, 5 Nov 2025 09:12:04 +0100, Dave Hansen wrote:
>>> Let me clarify what we need to know:
>>>
>>> Will you (or your employer) be running such updated 32bit kernels on
>>> hardware that supports MCEs.
>>>
>>> In other words: is this change driver by *real demand*
>>
>> Thanks! Asking like this, I completely understand now.
>>
>> We won't directly upgrade the kernel to 6.18.x (or later versions) to use
>> this feature, but if Linux community approves these patches, we will
>> backport it to 5.10.x and use it. I know that the page-flags in 5.10.x
>> have been exhausted, but we can work around them by adjusting
>> SECTION_SIZE_BITS/MAX_PHYSMEM_BITS to free up a page flag.
>> Another patch I submitted for arm32:
>> Link: https://lore.kernel.org/20250922021453.3939-1-xieyuanbin1@huawei.com
>> , follows the same logic.
>>
>> Currently, there is a clear demand for ARM32, while the demand for x86 is
>> still under discussion.
>>
>>> or just by "oh
>>> look, we can enable that now, I can come up with a theoretical use case
>>> but I don't know if anybody would actually care"?
>>
>> It can also be said that way. In fact, when developing the demand
>> "support MEMORY_FAILURE for 32-bit OS" in version 5.10.x, I found that the
>> latest version already supported this feature, so I submitted these
>> patches, and hope others can benefit from it as well.
>
> Hello, David Hildenbrand and Dave Hansen!
>
> Do you have any other comments on this patch? If you think that
> supporting memory-failure on x86_32 is meaningless, I will only submit
> patch 2 in the v3 patches.

I'd say, if nobody will really make use of that right now (customer
request etc), just leave x86 alone for now.

--
Cheers

David