Re: [PATCH] mm/page_table_check: fix accessing unmapped ptep

[Miaohe Lin]

On 2022/5/27 2:31, Pasha Tatashin wrote:
>>> Miaohe, please store the ptep, or maybe drop this patch entirely.
>>
>> I think it's best to fix it.  I rewrote the changelog as
>>
>> : ptep is unmapped too early, so ptep could theoretically be accessed while
>> : it's unmapped.  This might become a problem if/when CONFIG_HIGHPTE becomes
>> : available on riscv.
>> :
>> : Fix it by deferring pte_unmap() until page table checking is done.
>>
>> I'll retain the Fixes:.  This doesn't imply cc:stable in MM, and anyone
>> who backports the original patchset will want to know about this fixup.
> Makes sense.
> 
> 
>> And I queued a fixup for the thing Matthew noticed.
> Thank you Andrew.
> 

Many thanks for all of your comments, review and fixup! :)

> Pasha
> .
>