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[35.233.69.230]) by smtp.gmail.com with ESMTPSA id k4sm29442912wrd.9.2021.03.23.02.47.11 (version=TLS1_3 cipher=TLS_AES_256_GCM_SHA384 bits=256/256); Tue, 23 Mar 2021 02:47:11 -0700 (PDT) Date: Tue, 23 Mar 2021 09:47:08 +0000 From: Quentin Perret To: Marc Zyngier Cc: catalin.marinas@arm.com, james.morse@arm.com, julien.thierry.kdev@gmail.com, suzuki.poulose@arm.com, android-kvm@google.com, seanjc@google.com, mate.toth-pal@arm.com, linux-kernel@vger.kernel.org, linux-arm-kernel@lists.infradead.org, kernel-team@android.com, kvmarm@lists.cs.columbia.edu, tabba@google.com, ardb@kernel.org, mark.rutland@arm.com, dbrazdil@google.com Subject: Re: [PATCH 2/3] KVM: arm64: Generate final CTR_EL0 value when running in Protected mode Message-ID: References: <20210322164828.800662-1-maz@kernel.org> <20210322164828.800662-3-maz@kernel.org> <87k0pzghlx.wl-maz@kernel.org> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <87k0pzghlx.wl-maz@kernel.org> Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Hi Marc, On Monday 22 Mar 2021 at 18:37:14 (+0000), Marc Zyngier wrote: > Can't say I'm keen on the yucky bit, but here's an alternative (ha!) > for you: > > diff --git a/arch/arm64/include/asm/assembler.h b/arch/arm64/include/asm/assembler.h > index 1a4cee7eb3c9..7582c3bd2f05 100644 > --- a/arch/arm64/include/asm/assembler.h > +++ b/arch/arm64/include/asm/assembler.h > @@ -278,6 +278,9 @@ alternative_else > ldr_l \reg, arm64_ftr_reg_ctrel0 + ARM64_FTR_SYSVAL > alternative_endif > #else > +alternative_if_not ARM64_KVM_PROTECTED_MODE > + ASM_BUG() > +alternative_else_nop_endif > alternative_cb kvm_compute_final_ctr_el0 > movz \reg, #0 > movk \reg, #0, lsl #16 > > Yes, it is one more instruction, but it is cleaner and allows us to > from the first patch of the series. > > What do you think? Yes, I think having the ASM_BUG() in this macro is bit nicer and I doubt the additional nop will make any difference, so this is looking good to me! Thanks, Quentin 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=-8.6 required=3.0 tests=BAYES_00,DKIM_ADSP_CUSTOM_MED, DKIM_INVALID,DKIM_SIGNED,HEADER_FROM_DIFFERENT_DOMAINS,INCLUDES_PATCH, MAILING_LIST_MULTI,SPF_HELO_NONE,SPF_PASS 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 6A093C433C1 for ; Tue, 23 Mar 2021 09:47:17 +0000 (UTC) Received: from mm01.cs.columbia.edu (mm01.cs.columbia.edu [128.59.11.253]) by mail.kernel.org (Postfix) with ESMTP id D26E6619C0 for ; Tue, 23 Mar 2021 09:47:16 +0000 (UTC) DMARC-Filter: OpenDMARC Filter v1.3.2 mail.kernel.org D26E6619C0 Authentication-Results: mail.kernel.org; dmarc=fail (p=reject dis=none) header.from=google.com Authentication-Results: mail.kernel.org; spf=pass smtp.mailfrom=kvmarm-bounces@lists.cs.columbia.edu Received: from localhost (localhost [127.0.0.1]) by mm01.cs.columbia.edu (Postfix) with ESMTP id 46FCE4B401; Tue, 23 Mar 2021 05:47:16 -0400 (EDT) X-Virus-Scanned: at lists.cs.columbia.edu Authentication-Results: mm01.cs.columbia.edu (amavisd-new); dkim=softfail (fail, message has been altered) header.i=@google.com Received: from mm01.cs.columbia.edu ([127.0.0.1]) by localhost (mm01.cs.columbia.edu [127.0.0.1]) (amavisd-new, port 10024) with ESMTP id hKZvsCwvAe1d; Tue, 23 Mar 2021 05:47:15 -0400 (EDT) Received: from mm01.cs.columbia.edu (localhost [127.0.0.1]) by mm01.cs.columbia.edu (Postfix) with ESMTP id 474D94B3E8; Tue, 23 Mar 2021 05:47:15 -0400 (EDT) Received: from localhost (localhost [127.0.0.1]) by mm01.cs.columbia.edu (Postfix) with ESMTP id 0C7924B3E5 for ; Tue, 23 Mar 2021 05:47:14 -0400 (EDT) X-Virus-Scanned: at lists.cs.columbia.edu Received: from mm01.cs.columbia.edu ([127.0.0.1]) by localhost (mm01.cs.columbia.edu [127.0.0.1]) (amavisd-new, port 10024) with ESMTP id OULiGgk9UEix for ; Tue, 23 Mar 2021 05:47:13 -0400 (EDT) Received: from mail-wr1-f48.google.com (mail-wr1-f48.google.com [209.85.221.48]) by mm01.cs.columbia.edu (Postfix) with ESMTPS id EE5484B3B0 for ; Tue, 23 Mar 2021 05:47:12 -0400 (EDT) Received: by mail-wr1-f48.google.com with SMTP id v4so20054934wrp.13 for ; Tue, 23 Mar 2021 02:47:12 -0700 (PDT) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=google.com; s=20161025; h=date:from:to:cc:subject:message-id:references:mime-version :content-disposition:in-reply-to; bh=oEiL3agt/74r7enmoTbEE0QlFnF8CJn1Y4avzKhgTiU=; b=YUFx/qgDiqyZgnG8fBQV5CEOQ9+BCRiJTNLw0U/Sjtwv7xDzYaCvOnt/DijlqjJDeq 4gQ1ijgTeZbWSdb+trVyRWjQKbmgFIyw4kGzPHLfck/FJdRXsv6bJpcjqeUqY7ghYvwq pRcEi12K2xC6zj3zsdQHR7GQAz649sWNk0M5X3vcihlgBrPbW/ysFTU3zhgqPGfOiyln Ce/J3a+l+5yKFk7jm7otSR8CvCnQGsnVqlJVGNBKTlVXojSRlpjhpm+gC9AtYVeX6D4+ uJijgatuuL+mfS0/3DkfrCgbc1Hn0xyCXdplBpsN8aHekogkBv5nmPi8VJ893Vsd2gbg iDTA== X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20161025; h=x-gm-message-state:date:from:to:cc:subject:message-id:references :mime-version:content-disposition:in-reply-to; bh=oEiL3agt/74r7enmoTbEE0QlFnF8CJn1Y4avzKhgTiU=; b=oPGdRgDf7oDEEma4uE4ZGRCpRFwfwAInqG29cTVXatt7x3difMuPiqAGK64Vx2ZB89 n7Z6urWseoMRYWHDTztT4x2CWoA7UZAsyBlRKOgk21pkuVGgrBADm1pRPyITvSBN5HA6 ZVWz1PRIOvI4WksOhyISkK7IAvdEzabAFk7NeuiIpJ5C/iptLqM4A+86hHrBXrzExv1Y AW1uM4FT3pKLDaY4O/PHMqPhCt0+cuL0xG6pId4s43RuNGs5WEMVDHVM0DvBzpW1Ghlt gPjzASvnOr6xtcpc+Ir+R+a/m7EsB4IGUBbNZXe5dzAWB6hXTVvSHsuh4R6H8pYPDIh+ 41Vg== X-Gm-Message-State: AOAM532CoP6YCCb5Sc3bQv2GLv2rgTgHvG5Gz/1Bd2IeXAcyexgRMZ5c 2mn0l0oYp6PgtfYzHhbyTDS2Cw== X-Google-Smtp-Source: ABdhPJwZod2yQE1XjdtryqkkNyVhfuXXaVYhV4/ZQg1dkULLQ1uIrVQJ3DN+46T9qwKAV2wA8h4DIw== X-Received: by 2002:adf:ee4f:: with SMTP id w15mr3039063wro.199.1616492831791; Tue, 23 Mar 2021 02:47:11 -0700 (PDT) Received: from google.com (230.69.233.35.bc.googleusercontent.com. [35.233.69.230]) by smtp.gmail.com with ESMTPSA id k4sm29442912wrd.9.2021.03.23.02.47.11 (version=TLS1_3 cipher=TLS_AES_256_GCM_SHA384 bits=256/256); Tue, 23 Mar 2021 02:47:11 -0700 (PDT) Date: Tue, 23 Mar 2021 09:47:08 +0000 From: Quentin Perret To: Marc Zyngier Subject: Re: [PATCH 2/3] KVM: arm64: Generate final CTR_EL0 value when running in Protected mode Message-ID: References: <20210322164828.800662-1-maz@kernel.org> <20210322164828.800662-3-maz@kernel.org> <87k0pzghlx.wl-maz@kernel.org> MIME-Version: 1.0 Content-Disposition: inline In-Reply-To: <87k0pzghlx.wl-maz@kernel.org> Cc: android-kvm@google.com, catalin.marinas@arm.com, mate.toth-pal@arm.com, tabba@google.com, linux-kernel@vger.kernel.org, linux-arm-kernel@lists.infradead.org, seanjc@google.com, kernel-team@android.com, kvmarm@lists.cs.columbia.edu X-BeenThere: kvmarm@lists.cs.columbia.edu X-Mailman-Version: 2.1.14 Precedence: list List-Id: Where KVM/ARM decisions are made List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Content-Type: text/plain; charset="us-ascii" Content-Transfer-Encoding: 7bit Errors-To: kvmarm-bounces@lists.cs.columbia.edu Sender: kvmarm-bounces@lists.cs.columbia.edu Hi Marc, On Monday 22 Mar 2021 at 18:37:14 (+0000), Marc Zyngier wrote: > Can't say I'm keen on the yucky bit, but here's an alternative (ha!) > for you: > > diff --git a/arch/arm64/include/asm/assembler.h b/arch/arm64/include/asm/assembler.h > index 1a4cee7eb3c9..7582c3bd2f05 100644 > --- a/arch/arm64/include/asm/assembler.h > +++ b/arch/arm64/include/asm/assembler.h > @@ -278,6 +278,9 @@ alternative_else > ldr_l \reg, arm64_ftr_reg_ctrel0 + ARM64_FTR_SYSVAL > alternative_endif > #else > +alternative_if_not ARM64_KVM_PROTECTED_MODE > + ASM_BUG() > +alternative_else_nop_endif > alternative_cb kvm_compute_final_ctr_el0 > movz \reg, #0 > movk \reg, #0, lsl #16 > > Yes, it is one more instruction, but it is cleaner and allows us to > from the first patch of the series. > > What do you think? Yes, I think having the ASM_BUG() in this macro is bit nicer and I doubt the additional nop will make any difference, so this is looking good to me! Thanks, Quentin _______________________________________________ kvmarm mailing list kvmarm@lists.cs.columbia.edu https://lists.cs.columbia.edu/mailman/listinfo/kvmarm 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=-9.0 required=3.0 tests=BAYES_00,DKIMWL_WL_HIGH, DKIM_ADSP_CUSTOM_MED,DKIM_SIGNED,DKIM_VALID,HEADER_FROM_DIFFERENT_DOMAINS, INCLUDES_PATCH,MAILING_LIST_MULTI,SPF_HELO_NONE,SPF_PASS 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 29528C433C1 for ; Tue, 23 Mar 2021 09:48:46 +0000 (UTC) Received: from desiato.infradead.org (desiato.infradead.org [90.155.92.199]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by mail.kernel.org (Postfix) with ESMTPS id BF24D619BD for ; Tue, 23 Mar 2021 09:48:45 +0000 (UTC) DMARC-Filter: OpenDMARC Filter v1.3.2 mail.kernel.org BF24D619BD Authentication-Results: mail.kernel.org; dmarc=fail (p=reject dis=none) header.from=google.com Authentication-Results: mail.kernel.org; spf=none smtp.mailfrom=linux-arm-kernel-bounces+linux-arm-kernel=archiver.kernel.org@lists.infradead.org DKIM-Signature: v=1; a=rsa-sha256; q=dns/txt; c=relaxed/relaxed; d=lists.infradead.org; s=desiato.20200630; h=Sender:Content-Transfer-Encoding :Content-Type:List-Subscribe:List-Help:List-Post:List-Archive: List-Unsubscribe:List-Id:In-Reply-To:MIME-Version:References:Message-ID: Subject:Cc:To:From:Date:Reply-To:Content-ID:Content-Description:Resent-Date: Resent-From:Resent-Sender:Resent-To:Resent-Cc:Resent-Message-ID:List-Owner; bh=hia2aBLCWBQxCxeQPyc4ntxKX9gvkDVLFwRtUsoOlUM=; b=h8Agv4d/WJ5yGRm+w95nd606e rz0G6Nc0hriqtRCPD0UOvhVPWlRK1mR2Zswb7zT+ppE2Ox7o41mLfPy5vXuxlv2Eyo95mPWxi2YSl seq1i+bDSJ+j2klnQw2jyLJaO0leoG6REuK4pOLkcOiehoAQjnF3eF3KWh9e/xU5vWAOeAFR/ya1I 7uC11feG4g2uiJOqRu0F1Ts2Jwy722ZGRpg6gIg37LkGWgKQ6e2E4c29Hq/Vhom8SmdrUBLdUrZ1e 519bCL+cTPXYeXb56tDxKRuVrZPGec6RLNNdKgG0ZwDduyFYkYgXsplaznmev6OJkiFP7FQj2e2ND qyuL8UYIQ==; Received: from localhost ([::1] helo=desiato.infradead.org) by desiato.infradead.org with esmtp (Exim 4.94 #2 (Red Hat Linux)) id 1lOdd9-00EVls-NR; Tue, 23 Mar 2021 09:47:19 +0000 Received: from mail-wr1-x432.google.com ([2a00:1450:4864:20::432]) by desiato.infradead.org with esmtps (Exim 4.94 #2 (Red Hat Linux)) id 1lOdd2-00EVkA-Jz for linux-arm-kernel@lists.infradead.org; Tue, 23 Mar 2021 09:47:14 +0000 Received: by mail-wr1-x432.google.com with SMTP id c8so7146147wrq.11 for ; Tue, 23 Mar 2021 02:47:12 -0700 (PDT) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=google.com; s=20161025; h=date:from:to:cc:subject:message-id:references:mime-version :content-disposition:in-reply-to; bh=oEiL3agt/74r7enmoTbEE0QlFnF8CJn1Y4avzKhgTiU=; b=YUFx/qgDiqyZgnG8fBQV5CEOQ9+BCRiJTNLw0U/Sjtwv7xDzYaCvOnt/DijlqjJDeq 4gQ1ijgTeZbWSdb+trVyRWjQKbmgFIyw4kGzPHLfck/FJdRXsv6bJpcjqeUqY7ghYvwq pRcEi12K2xC6zj3zsdQHR7GQAz649sWNk0M5X3vcihlgBrPbW/ysFTU3zhgqPGfOiyln Ce/J3a+l+5yKFk7jm7otSR8CvCnQGsnVqlJVGNBKTlVXojSRlpjhpm+gC9AtYVeX6D4+ uJijgatuuL+mfS0/3DkfrCgbc1Hn0xyCXdplBpsN8aHekogkBv5nmPi8VJ893Vsd2gbg iDTA== X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20161025; h=x-gm-message-state:date:from:to:cc:subject:message-id:references :mime-version:content-disposition:in-reply-to; bh=oEiL3agt/74r7enmoTbEE0QlFnF8CJn1Y4avzKhgTiU=; b=RVIxTRKaANhrE0b9ldZxX7xj+ZhcZ5NH7xHfE8xiKd5SGoWwQiNRzL+sgR6dP/wxZf IMKcYaWX9oQMQAblzFVMG2BMpICnbHgx9hFikTYYBVvZW+f9YWMQs+cC1wmnK+OBbJxp 6PpHtNJobmdwanQAma2XO64A3l0Z7UbBKS1xdL70TJ14MD4+hI6J4xlDYBfMUhgQBlLk PsvFql21PnhG5Z+m+D9fB6omDsmgvMPX+tCOfIyifLdRjp0108y08tVexbv0ZXZeOBGs gNHQAAJrp8B76ypi9+e6X4hLrMW8mqxyfQSr/Zjrqt5eNpRt40vvkDOXnnKsFffICoPo sbvg== X-Gm-Message-State: AOAM533nY5ZEeAIsTKyg30JqTG1UfI093qvycSYpYlkwOaiT+ufE9cDs vhuPPHkGkq6fnJQwYV41aXKGLQ== X-Google-Smtp-Source: ABdhPJwZod2yQE1XjdtryqkkNyVhfuXXaVYhV4/ZQg1dkULLQ1uIrVQJ3DN+46T9qwKAV2wA8h4DIw== X-Received: by 2002:adf:ee4f:: with SMTP id w15mr3039063wro.199.1616492831791; Tue, 23 Mar 2021 02:47:11 -0700 (PDT) Received: from google.com (230.69.233.35.bc.googleusercontent.com. [35.233.69.230]) by smtp.gmail.com with ESMTPSA id k4sm29442912wrd.9.2021.03.23.02.47.11 (version=TLS1_3 cipher=TLS_AES_256_GCM_SHA384 bits=256/256); Tue, 23 Mar 2021 02:47:11 -0700 (PDT) Date: Tue, 23 Mar 2021 09:47:08 +0000 From: Quentin Perret To: Marc Zyngier Cc: catalin.marinas@arm.com, james.morse@arm.com, julien.thierry.kdev@gmail.com, suzuki.poulose@arm.com, android-kvm@google.com, seanjc@google.com, mate.toth-pal@arm.com, linux-kernel@vger.kernel.org, linux-arm-kernel@lists.infradead.org, kernel-team@android.com, kvmarm@lists.cs.columbia.edu, tabba@google.com, ardb@kernel.org, mark.rutland@arm.com, dbrazdil@google.com Subject: Re: [PATCH 2/3] KVM: arm64: Generate final CTR_EL0 value when running in Protected mode Message-ID: References: <20210322164828.800662-1-maz@kernel.org> <20210322164828.800662-3-maz@kernel.org> <87k0pzghlx.wl-maz@kernel.org> MIME-Version: 1.0 Content-Disposition: inline In-Reply-To: <87k0pzghlx.wl-maz@kernel.org> X-CRM114-Version: 20100106-BlameMichelson ( TRE 0.8.0 (BSD) ) MR-646709E3 X-CRM114-CacheID: sfid-20210323_094712_777300_40B46232 X-CRM114-Status: GOOD ( 17.36 ) X-BeenThere: linux-arm-kernel@lists.infradead.org X-Mailman-Version: 2.1.34 Precedence: list List-Id: List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , 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 Hi Marc, On Monday 22 Mar 2021 at 18:37:14 (+0000), Marc Zyngier wrote: > Can't say I'm keen on the yucky bit, but here's an alternative (ha!) > for you: > > diff --git a/arch/arm64/include/asm/assembler.h b/arch/arm64/include/asm/assembler.h > index 1a4cee7eb3c9..7582c3bd2f05 100644 > --- a/arch/arm64/include/asm/assembler.h > +++ b/arch/arm64/include/asm/assembler.h > @@ -278,6 +278,9 @@ alternative_else > ldr_l \reg, arm64_ftr_reg_ctrel0 + ARM64_FTR_SYSVAL > alternative_endif > #else > +alternative_if_not ARM64_KVM_PROTECTED_MODE > + ASM_BUG() > +alternative_else_nop_endif > alternative_cb kvm_compute_final_ctr_el0 > movz \reg, #0 > movk \reg, #0, lsl #16 > > Yes, it is one more instruction, but it is cleaner and allows us to > from the first patch of the series. > > What do you think? Yes, I think having the ASM_BUG() in this macro is bit nicer and I doubt the additional nop will make any difference, so this is looking good to me! Thanks, Quentin _______________________________________________ linux-arm-kernel mailing list linux-arm-kernel@lists.infradead.org http://lists.infradead.org/mailman/listinfo/linux-arm-kernel