From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: X-Spam-Checker-Version: SpamAssassin 3.4.0 (2014-02-07) on aws-us-west-2-korg-lkml-1.web.codeaurora.org X-Spam-Level: X-Spam-Status: No, score=-12.7 required=3.0 tests=BAYES_00,DKIMWL_WL_HIGH, DKIM_SIGNED,DKIM_VALID,DKIM_VALID_AU,INCLUDES_PATCH,MAILING_LIST_MULTI, SPF_HELO_NONE,SPF_PASS,USER_AGENT_SANE_1 autolearn=ham autolearn_force=no version=3.4.0 Received: from mail.kernel.org (mail.kernel.org [198.145.29.99]) by smtp.lore.kernel.org (Postfix) with ESMTP id B1860C433E6 for ; Fri, 12 Mar 2021 09:26:51 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id 883CE64FDD for ; Fri, 12 Mar 2021 09:26:51 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S232915AbhCLJ0V (ORCPT ); Fri, 12 Mar 2021 04:26:21 -0500 Received: from mail.kernel.org ([198.145.29.99]:46706 "EHLO mail.kernel.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S232932AbhCLJ0C (ORCPT ); Fri, 12 Mar 2021 04:26:02 -0500 Received: by mail.kernel.org (Postfix) with ESMTPSA id B85FE64ED7; Fri, 12 Mar 2021 09:25:59 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=k20201202; t=1615541162; bh=lt1IwrNUaz19OAxDfxgi2aiw3GOvHySCHyMhts/ttlc=; h=Date:From:To:Cc:Subject:References:In-Reply-To:From; b=fj6Lfc2WDvpu5FN2uF4nmKoY/pKj+yD6c1fxrHH/2C9G+WxYhA5XcICxqbDZryfHb UILcjc19PqDMIxnxPslMIKU2n5/nLiV1Ky0Z9E//xMmLGgTQbxgeTfZU2kAWYZBxoK Rw0RHvov/Ewu9lspDaalDVnJc6UQlHkTT0o+ubMrV+1eER3D8uUTJ/+L6pVBO3wu1g kIfJ2rWYtUX9JtkeoRaoE/+5gOfR4fv6xG95DkxlY7BkzgE1Yyi8ZdhqCgebkwanaU mLNNKPkrM9JHPA5MDb6489q/r3qq5RVsRy0VwZST8KtNuShKhUgPjyWON19f6p7gH9 G9dOWm5SsN/+g== Date: Fri, 12 Mar 2021 09:25:56 +0000 From: Will Deacon To: Quentin Perret Cc: catalin.marinas@arm.com, maz@kernel.org, james.morse@arm.com, julien.thierry.kdev@gmail.com, suzuki.poulose@arm.com, android-kvm@google.com, linux-kernel@vger.kernel.org, kernel-team@android.com, kvmarm@lists.cs.columbia.edu, linux-arm-kernel@lists.infradead.org, tabba@google.com, mark.rutland@arm.com, dbrazdil@google.com, mate.toth-pal@arm.com, seanjc@google.com, robh+dt@kernel.org, ardb@kernel.org Subject: Re: [PATCH v4 13/34] KVM: arm64: Enable access to sanitized CPU features at EL2 Message-ID: <20210312092556.GA32016@willie-the-truck> References: <20210310175751.3320106-1-qperret@google.com> <20210310175751.3320106-14-qperret@google.com> <20210311193638.GE31586@willie-the-truck> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: User-Agent: Mutt/1.10.1 (2018-07-13) Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On Fri, Mar 12, 2021 at 06:34:09AM +0000, Quentin Perret wrote: > On Thursday 11 Mar 2021 at 19:36:39 (+0000), Will Deacon wrote: > > On Wed, Mar 10, 2021 at 05:57:30PM +0000, Quentin Perret wrote: > > > diff --git a/arch/arm64/kvm/sys_regs.c b/arch/arm64/kvm/sys_regs.c > > > index 4f2f1e3145de..84be93df52fa 100644 > > > --- a/arch/arm64/kvm/sys_regs.c > > > +++ b/arch/arm64/kvm/sys_regs.c > > > @@ -21,6 +21,7 @@ > > > #include > > > #include > > > #include > > > +#include > > > #include > > > #include > > > #include > > > @@ -2775,3 +2776,23 @@ void kvm_sys_reg_table_init(void) > > > /* Clear all higher bits. */ > > > cache_levels &= (1 << (i*3))-1; > > > } > > > + > > > +#undef KVM_HYP_CPU_FTR_REG > > > +#define KVM_HYP_CPU_FTR_REG(id, name) \ > > > + { .sys_id = id, .dst = (struct arm64_ftr_reg *)&kvm_nvhe_sym(name) }, > > > +struct __ftr_reg_copy_entry { > > > + u32 sys_id; > > > + struct arm64_ftr_reg *dst; > > > +} hyp_ftr_regs[] __initdata = { > > > + #include > > > +}; > > > > This looks a bit elaborate to me. Why can't you just spell things out here > > like: > > > > #define KVM_HYP_CPU_FTR_REG(id, name) \ > > { .sys_id = id, .dst = (struct arm64_ftr_reg *)&kvm_nvhe_sym(name) } > > > > struct __ftr_reg_copy_entry { > > u32 sys_id; > > struct arm64_ftr_reg *dst; > > } hyp_ftr_regs[] __initdata = { > > KVM_HYP_CPU_FTR_REG(SYS_CTR_EL0, arm64_ftr_reg_ctrel0), > > ... > > }; > > > > and then have the header file be a normal, guarded header which just > > declares these things? The id parameter to the macro isn't used there. > > I just tried to reduce the boilerplate as much as possible -- in the > current form you only need to add additional features to the header > it'll 'just work'. I don't really think it's worth it -- people are used to having to add declarations for things, so keeping it simple should be fine. Will