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charset=utf-8 Content-Disposition: inline In-Reply-To: <202402050445.0331B94A73@keescook> X-Rspam-User: X-Rspamd-Server: rspam12 X-Rspamd-Queue-Id: 66327C0032 X-Stat-Signature: ut7q7ewy3r8aein46jy8ufrbs1sqtuw1 X-HE-Tag: 1707481842-512447 X-HE-Meta: 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 Ub04yvrs 0UH8hcDAigNJt6nOsXTebUoSnisnuF9F8V2RvJ0ZxubJu5cdqbwwOK2TSGIoOXD9+2tIqh/2RlsmNcl7frQEZJpNDyXFCLwU7il5kU0dEvSvRhcJVVPdRVbu07OGE1xvXTa0yRXTgRiIdwCWmXoprof41ClupCy/nMtGcbQLohleyTMaAOnL63W/+yh8HYoGme7OI6CD/+nCX254GEpLma/dRz5H0Fv764JHQvO035HrPu03niJWzVAExSPOIWG1Lf08lNiKl0kyizSMf/7oNVCbfgiRAp5dQOoSJ+78laG1JQD3+TkGwwA4vvSdtec9+2Ixrc11TZIYJVYDx3TjXtkDDQUdvGq9yyHdGsjnb3cFjPcc3Z9wLzwKGsoxebN2MlasLlhX1G+EhbiWuiKkb6me1JfbH3mig9x4ccbiI+sqq0lxJqQO+QilVyA64pmQRCxFkqjQOjC6oMqQzI3juBuPBwrA/e/4a0sqU 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 Mon, Feb 05, 2024 at 04:48:08AM -0800, Kees Cook wrote: > On Mon, Feb 05, 2024 at 12:51:43PM +0300, Alexey Dobriyan wrote: > > +#define ARCH_AT_PAGE_SHIFT_MASK \ > > + do { \ > > + u32 val = 1 << 12; \ > > + if (boot_cpu_has(X86_FEATURE_PSE)) { \ > > + val |= 1 << 21; \ > > + } \ > > + if (boot_cpu_has(X86_FEATURE_GBPAGES)) { \ > > + val |= 1 << 30; \ > > + } \ > > Can we use something besides literal "12", "21", and "30" values here? Ehh, no, why? Inside x86_64 the page shifts are very specific numbers, they won't change.