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charset=us-ascii Content-Disposition: inline In-Reply-To: <7525a9f6-b431-4404-2878-898e52905d4a@linux.alibaba.com> X-Rspam-User: X-Rspamd-Server: rspam03 X-Stat-Signature: sz1dqrrk8dz5df5sh6gj6smqzz9iecoa X-Rspamd-Queue-Id: F151940011 X-HE-Tag: 1682333656-85038 X-HE-Meta: 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 H0hNxJcn BCcVrG93RvrPz7JOoV2bjptCLS+odplNkx6PkYK0d3wKBvGTdCQKotKSFUAsg50UAEHysinokvxpnVWsjAxnRtjJuk2nHZayBBYItHvp1vglZfkkqEQ/u+XdjS65Q+CENldT9MpzWn6jqu6jyhDibW3NcoNrN4scAr33pU0MLNRWm6Z+rYdXr410K2o5COvpjEHftTToBXJYUzCYkV8ZNqA6bC2k4BfwHJuNoxxnIs8fL8arSl/nfnxm1RWIf/sjXVD8Peh1wd3Fgwblqo9B7QUne2EYF2+vD2S1nIbn5lZ5xMUOykFJELyrxE8LIjXqx6n3t X-Bogosity: Ham, tests=bogofilter, spamicity=0.000000, version=1.2.4 Sender: owner-linux-mm@kvack.org Precedence: bulk X-Loop: owner-majordomo@kvack.org List-ID: On Mon 24-04-23 18:46:40, Baolin Wang wrote: > > > On 4/24/2023 5:50 PM, Michal Hocko wrote: > > On Sun 23-04-23 18:59:10, Baolin Wang wrote: > > > We've already used pfn_to_online_page() for start pfn to make sure > > > > Who is we? I do not see any note explicitly requiring that start_pfn has > > to be valid for __pageblock_pfn_to_page. > > Sorry for confusing, what I mean is the __pageblock_pfn_to_page() function, > which has used pfn_to_online_page() for start pfn. So the pfn_valid() in > __pageblock_pfn_to_page() for start pfn is unnecessary. > > I will update the commit log to make it clear. Your comment suggested that the check _has_ already been done. Which is not the case. pfn_to_online_page is called later in the function so I guess you should rephrase as following: " __pageblock_pfn_to_page currently performs both pfn_valid check and pfn_to_online_page. The former one is redundant because the latter is a stronger check. Drop pfn_valid. " With that or something going along with that. Feel free to add Acked-by: Michal Hocko > > > it is online and valid, so the pfn_valid() for the start pfn is > > > unnecessary, drop it. > > > > > > Signed-off-by: Baolin Wang > > > Reviewed-by: David Hildenbrand > > > Reviewed-by: "Huang, Ying" > > > --- > > > Changes from v1: > > > - Collect reviewed tags. Thanks David and Ying. > > > --- > > > mm/page_alloc.c | 2 +- > > > 1 file changed, 1 insertion(+), 1 deletion(-) > > > > > > diff --git a/mm/page_alloc.c b/mm/page_alloc.c > > > index 9de2a18519a1..6457b64fe562 100644 > > > --- a/mm/page_alloc.c > > > +++ b/mm/page_alloc.c > > > @@ -1512,7 +1512,7 @@ struct page *__pageblock_pfn_to_page(unsigned long start_pfn, > > > /* end_pfn is one past the range we are checking */ > > > end_pfn--; > > > - if (!pfn_valid(start_pfn) || !pfn_valid(end_pfn)) > > > + if (!pfn_valid(end_pfn)) > > > return NULL; > > > start_page = pfn_to_online_page(start_pfn); > > > -- > > > 2.27.0 > > -- Michal Hocko SUSE Labs