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x86_64-pc-linux-gnu) Mime-Version: 1.0 X-BeenThere: linux-arm-kernel@lists.infradead.org X-Mailman-Version: 2.1.29 Precedence: list List-Id: List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Cc: linux-arch@vger.kernel.org, Szabolcs Nagy , Andrey Konovalov , Kevin Brodsky , Steven Price , Peter Collingbourne , linux-mm@kvack.org, Vincenzo Frascino , Will Deacon , Dave P Martin , linux-arm-kernel@lists.infradead.org Content-Type: text/plain; charset="us-ascii" Content-Transfer-Encoding: 7bit Sender: "linux-arm-kernel" Errors-To: linux-arm-kernel-bounces+linux-arm-kernel=archiver.kernel.org@lists.infradead.org On Wed, 24 Jun 2020 18:52:25 +0100 Catalin Marinas wrote: > From: Steven Price > > For arm64 MTE support it is necessary to be able to mark pages that > contain user space visible tags that will need to be saved/restored e.g. > when swapped out. > > To support this add a new arch specific flag (PG_ARCH_2) that arch code > can opt into using ARCH_USES_PG_ARCH_2. > > ... > > --- a/fs/proc/page.c > +++ b/fs/proc/page.c > @@ -217,6 +217,9 @@ u64 stable_page_flags(struct page *page) > u |= kpf_copy_bit(k, KPF_PRIVATE_2, PG_private_2); > u |= kpf_copy_bit(k, KPF_OWNER_PRIVATE, PG_owner_priv_1); > u |= kpf_copy_bit(k, KPF_ARCH, PG_arch_1); > +#ifdef CONFIG_ARCH_USES_PG_ARCH_2 > + u |= kpf_copy_bit(k, KPF_ARCH_2, PG_arch_2); > +#endif Do we need CONFIG_ARCH_USES_PG_ARCH_2? What would be the downside to giving every architecture a PG_arch_2, but only arm64 uses it (at present)? _______________________________________________ linux-arm-kernel mailing list linux-arm-kernel@lists.infradead.org http://lists.infradead.org/mailman/listinfo/linux-arm-kernel