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charset=us-ascii Content-Disposition: inline In-Reply-To: X-Scanned-By: MIMEDefang 3.4.1 on 10.30.177.111 X-Rspamd-Server: rspam01 X-Stat-Signature: mcr4si3nrhibffa1eo83e46oxm3gf7aw X-Rspam-User: X-Rspamd-Queue-Id: 1FEDC1C000B X-HE-Tag: 1743516769-495668 X-HE-Meta: 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 CoFts9BR sFuuT1IRI869iMHPZT12rGc0Xclc0/fag8hl4EBZIRrTQE9aZEwmPCLZol7RSEy2jXeh8BY6RzqOdKGG4wkHOxVeNOoOEk54HLl7fZFAzBd/4JoTOKIR6acuqQvOPxE4NXf5eueMZzIzDjaQ71dCL8fIrxu5J3Fzrmji/YwCnrg/UFWwTk6AbKLFyLH/m5a3lDFqmZ6NyhBcWJkXYKrsRkpLAHVbMBKBGkvqsJRbkWWGmfB5OHzC7paugKaZG3Aeru8MMLTF1IJ6jcmsXPbeeJntrJg/SLdfzUF+1erpujwXFs3beOHD+kV/FR8zdQ3g9mjNig/dsTZRh1zqUPFcMLngyRL6vCZavf1Zd7zT2Il2u1dDmHdYEcawUUM4HkzN4GbnKbexU0xBNDNGdQIRjfrHRoB+NrqF1/pTePHl3jUloCekUstCSTVvWnpiUn1etv2z2 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 04/01/25 at 04:00pm, Oscar Salvador wrote: > On Tue, Apr 01, 2025 at 10:10:03AM +0200, David Hildenbrand wrote: > > On 31.03.25 10:13, Baoquan He wrote: > > > --- a/mm/gup.c > > > +++ b/mm/gup.c > > > @@ -2207,8 +2207,8 @@ size_t fault_in_safe_writeable(const char __user *uaddr, size_t size) > > > } while (start != end); > > > mmap_read_unlock(mm); > > > - if (size > (unsigned long)uaddr - start) > > > - return size - ((unsigned long)uaddr - start); > > > + if (size > start - (unsigned long)uaddr) > > > + return size - (start - (unsigned long)uaddr); > > > return 0; > > > } > > > EXPORT_SYMBOL(fault_in_safe_writeable); > > > > Can we instead just use the uaddr and start variables like in > > fault_in_readable? > > > > That is, turn "start" into a const and adjust uaddr instead. > > Yes, I think that would be much cleaner. > > Otherwise, this looks good to me. Will change in v3 as both of you suggested, thanks for reviewing this v2 series.