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Shutemov" Subject: Re: [RFC PATCH v11 08/29] KVM: Introduce per-page memory attributes Message-ID: References: <20230718234512.1690985-1-seanjc@google.com> <20230718234512.1690985-9-seanjc@google.com> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: X-Rspam-User: X-Rspamd-Server: rspam12 X-Rspamd-Queue-Id: 2C7C2100009 X-Stat-Signature: ad6htz6ij7usnsxa7h9uih6b5ftwboyh X-HE-Tag: 1690428448-537974 X-HE-Meta: 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 ff+MbztA LT8AYR0ji0xt86BKZIdDBy20l03+0tG30H1+HEUD02/bDlIsUuc7gcv1APNlUTHHIYmHGeQEicBLmb6MMrpTepWJGPlNAnA82EQHaWxm4zIM6+ARslrcIGpskJjzI4J20xgIH1TYNxdirwLLFfdfI/5krDVA/+6+lG34AyFAk7g+2+5Q0Lsb18tB+WeAmeM5iSEKNgOeGXhsN0Ozj5Gf49zjgEdxah0Um5SpEyAKf98t0Qn8hx80212x8wrpffO1FtpSh4a+AFAnM/ELYSjjAJLI/4iNHXDsKUTyukda9OiglaXo= 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 2023-07-26 at 08:59:53 -0700, Sean Christopherson wrote: > On Mon, Jul 24, 2023, Xu Yilun wrote: > > On 2023-07-18 at 16:44:51 -0700, Sean Christopherson wrote: > > > + if (WARN_ON_ONCE(start == end)) > > > + return -EINVAL; > > > > Also, is this check possible to be hit? Maybe remove it? > > It should be impossible to, hence the WARN. I added the check for two reasons: > (1) to help document that end is exclusive, and (2) to guard against future bugs. Understood. I'm good to it.