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charset=us-ascii Content-Disposition: inline In-Reply-To: X-Rspamd-Queue-Id: D124618000D X-Rspam-User: X-Stat-Signature: keksgkf3wxthbxonqrnc53k8zdynhtzz X-Rspamd-Server: rspam03 X-HE-Tag: 1707525698-72310 X-HE-Meta: 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 8OjMyMy8 YndXp91mJ7D0N1qFZehpnKtRc39DcWUKy7MRd0+cGkfY4dtolqpcrJMKHuU71I2IDN6LHek28Q+QCb14HH90aOtxf4oT7MNk+cqzlizuB3bDdvEaSdaQCoIrEDEP2QWSQKGC4 X-Bogosity: Ham, tests=bogofilter, spamicity=0.000003, 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 Fri, Feb 09, 2024 at 03:30:37PM +0300, Alexey Dobriyan wrote: > 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. Well, it's nicer to have meaningful words to describe these things. In fact, PAGE_SHIFT already exists for 12, and HPAGE_SHIFT already exists for 21. Please use those, and add another, perhaps GBPAGE_SHIFT, for 30. -Kees -- Kees Cook