Re: a question of split_huge_page

[Alex Shi]

å 2020/7/10 äå6:33, Kirill A. Shutemov åé:
> On Fri, Jul 10, 2020 at 12:51:58PM +0800, Alex Shi wrote:
>>
>>
>> å 2020/7/10 äå12:07, Kirill A. Shutemov åé:
>>> Right, and it's never got removed from LRU during the split. The tail
>>> pages have to be added to LRU because they now separate from the tail
>>> page.
>>>
>> According to the explaination, looks like we could remove the code path,
>> since it's never got into. (base on my v15 patchset). Any comments?
> 
> Yes. But why? It's reasonable failsafe that gives chance to recover if
> something goes wrong.
> 

Hi Kirill,

Sorry, I didn't get your points. IMHO, this fallback cann't work well,
since the head page isn't and shouldn't be added to lru. like the iommu issue
if a dma page added into lru list, it may be reclaim and lost. So, sorry, I
still don't know how this path could fix some wrong.

Thanks
Alex