From mboxrd@z Thu Jan 1 00:00:00 1970 Return-path: Received: from mail.skyhub.de ([5.9.137.197]) by bombadil.infradead.org with esmtps (Exim 4.94.2 #2 (Red Hat Linux)) id 1m8mPW-001ch8-Uz for kexec@lists.infradead.org; Wed, 28 Jul 2021 16:28:02 +0000 Date: Wed, 28 Jul 2021 18:28:01 +0200 From: Borislav Petkov Subject: Re: [PATCH 01/11] mm: Introduce a function to check for virtualization protection features Message-ID: References: MIME-Version: 1.0 Content-Disposition: inline In-Reply-To: List-Id: List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Content-Type: text/plain; charset="us-ascii" Content-Transfer-Encoding: 7bit Sender: "kexec" Errors-To: kexec-bounces+dwmw2=infradead.org@lists.infradead.org To: Christoph Hellwig Cc: Tom Lendacky , linux-kernel@vger.kernel.org, x86@kernel.org, linuxppc-dev@lists.ozlabs.org, linux-s390@vger.kernel.org, iommu@lists.linux-foundation.org, kvm@vger.kernel.org, linux-efi@vger.kernel.org, platform-driver-x86@vger.kernel.org, linux-graphics-maintainer@vmware.com, amd-gfx@lists.freedesktop.org, dri-devel@lists.freedesktop.org, kexec@lists.infradead.org, linux-fsdevel@vger.kernel.org, Andi Kleen , Tianyu Lan , Brijesh Singh On Wed, Jul 28, 2021 at 02:17:27PM +0100, Christoph Hellwig wrote: > So common checks obviously make sense, but I really hate the stupid > multiplexer. Having one well-documented helper per feature is much > easier to follow. We had that in x86 - it was called cpu_has_ where xxx is the feature bit. It didn't scale with the sheer amount of feature bits that kept getting added so we do cpu_feature_enabled(X86_FEATURE_XXX) now. The idea behind this is very similar - those protected guest flags will only grow in the couple of tens range - at least - so having a multiplexer is a lot simpler, I'd say, than having a couple of tens of helpers. And those PATTR flags should have good, readable names, btw. Thx. -- Regards/Gruss, Boris. https://people.kernel.org/tglx/notes-about-netiquette _______________________________________________ kexec mailing list kexec@lists.infradead.org http://lists.infradead.org/mailman/listinfo/kexec