Re: [Patch v2 2/4] mm/page_alloc.c: bad_[reason|flags] is not necessary when PageHWPoison

From: Wei Yang
Date: Mon Jan 20 2020 - 07:13:08 EST


On Mon, Jan 20, 2020 at 11:58:04AM +0530, Anshuman Khandual wrote:
>
>
>On 01/20/2020 08:34 AM, Wei Yang wrote:
>> Since function returns directly, bad_[reason|flags] is not used any
>> where.
>>
>> This is a following cleanup for commit e570f56cccd21 ("mm:
>> check_new_page_bad() directly returns in __PG_HWPOISON case")
>>
>> Signed-off-by: Wei Yang <richardw.yang@xxxxxxxxxxxxxxx>
>> Acked-by: David Rientjes <rientjes@xxxxxxxxxx>
>> ---
>> mm/page_alloc.c | 2 --
>> 1 file changed, 2 deletions(-)
>>
>> diff --git a/mm/page_alloc.c b/mm/page_alloc.c
>> index 0cf6218aaba7..a43b9d2482f2 100644
>> --- a/mm/page_alloc.c
>> +++ b/mm/page_alloc.c
>> @@ -2051,8 +2051,6 @@ static void check_new_page_bad(struct page *page)
>> if (unlikely(page_ref_count(page) != 0))
>> bad_reason = "nonzero _refcount";
>> if (unlikely(page->flags & __PG_HWPOISON)) {
>> - bad_reason = "HWPoisoned (hardware-corrupted)";
>> - bad_flags = __PG_HWPOISON;
>> /* Don't complain about hwpoisoned pages */
>> page_mapcount_reset(page); /* remove PageBuddy */
>> return;
>
>This bail out condition should be the first in the function
>check_new_page_bad() before evaluating bad_[reason|flags]
>as they will never be used.
>

This is reasonable.

>>

--
Wei Yang
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