Re: [PATCH] mm/memory-failure: fix infinite UCE for VM_PFNMAP pfn

[Jinjiang Tu <tujinjiang@huawei.com>]

在 2025/8/6 20:39, David Hildenbrand 写道:
> On 06.08.25 04:05, Jinjiang Tu wrote:
>> When memory_failure() is called for a already hwpoisoned pfn,
>> kill_accessing_process() will be called to kill current task. 
>> However, if
>> the vma of the accessing vaddr is VM_PFNMAP, walk_page_range() will skip
>> the vma in walk_page_test() and return 0.
>
> That check is dubious and it's on my todo list to revisit that, 
> because it doesn't make sense for COW VM_PFNMAP mappings.
>
> But I am curious, is this about having an anon page in a COW 
> VM_PFNMAP, or on "what kidn of page" do you get the fault?
The pfn is RAM pfn, which is mapped with remap_pfn_range(). There is no 
COW.