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charset="UTF-8" X-Rspamd-Server: rspam02 X-Rspamd-Queue-Id: 4C045100011 X-Stat-Signature: 1tr4busht9cruegca769b4jmjhjj6a4s X-Rspam-User: X-HE-Tag: 1756466439-591382 X-HE-Meta: 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 m7V7LxPN 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 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: List-Subscribe: List-Unsubscribe: On Thu Aug 28, 2025 at 6:31 PM UTC, Vlastimil Babka wrote: > On 8/27/25 17:30, Brendan Jackman wrote: >> On Wed Aug 27, 2025 at 2:13 AM UTC, Andrew Morton wrote: >>> On Tue, 26 Aug 2025 14:06:54 +0000 Brendan Jackman wrote: >>> >>>> Currently order is signed in one version of the function and unsigned in >>>> the other. Tidy that up. >>>> >>>> In page_alloc.c, order is unsigned in the vast majority of cases. But, >>>> there is a cluster of exceptions in compaction-related code (probably >>>> stemming from the fact that compact_control.order is signed). So, prefer >>>> local consistency and make this one signed too. >>>> >>> >>> grumble, pet peeve. Negative orders make no sense. Can we make >>> cc->order unsigned in order (heh) to make everything nice? >> >> I think we can't "just" do that: > > That part should be easy to convert to a compact_control flag. > Zi's point about going negative seems like more prone to overlook some case. > But worth trying and the cleanups I'd say. OK, I can take a look next week. From a quick glance it does seem to be worth having a sniff, there could be bugs in there where code is expecting non-negative and doing stuff like using it as a shift index, in cases where it can actually be negative.