Re: [PATCH] mm,hwpoison: unmap poisoned page before invalidation
From: Miaohe Lin
Date: Sun Mar 27 2022 - 22:41:57 EST
On 2022/3/28 10:24, Rik van Riel wrote:
> On Mon, 2022-03-28 at 10:14 +0800, Miaohe Lin wrote:
>> On 2022/3/27 4:14, Rik van Riel wrote:
>>
>>
>>>
>>>>> /* Retry if a clean page was removed
>>>>> from
>>>>> the cache. */
>>>>> - if (invalidate_inode_page(vmf->page))
>>>>> - poisonret = 0;
>>>>> - unlock_page(vmf->page);
>>>>> + if (invalidate_inode_page(page))
>>>>> + poisonret = VM_FAULT_NOPAGE;
>>>>> + unlock_page(page);
>>>
>>
>> Sure, but when I think more about this, it seems this fix isn't
>> ideal:
>> If VM_FAULT_NOPAGE is returned with page table unset, the process
>> will
>> re-trigger page fault again and again until invalidate_inode_page
>> succeeds
>> to evict the inode page. This might hang the process a really long
>> time.
>> Or am I miss something?
>>
> If invalidate_inode_page fails, we will return
> VM_FAULT_HWPOISON, and kill the task, instead
> of looping indefinitely.
Oh, really sorry! It's a drowsy Monday morning. :)
This patch looks good to me. Thanks!
Reviewed-by: Miaohe Lin <linmiaohe@xxxxxxxxxx>
>