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=-10.5 required=3.0 tests=BAYES_00,DKIMWL_WL_HIGH, DKIM_SIGNED,DKIM_VALID,INCLUDES_PATCH,MAILING_LIST_MULTI,SPF_HELO_NONE, SPF_PASS,URIBL_BLOCKED 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 1BD17C63777 for ; Mon, 30 Nov 2020 15:41:36 +0000 (UTC) Received: from merlin.infradead.org (merlin.infradead.org [205.233.59.134]) (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 9D1B920706 for ; Mon, 30 Nov 2020 15:41:35 +0000 (UTC) Authentication-Results: mail.kernel.org; dkim=pass (2048-bit key) header.d=lists.infradead.org header.i=@lists.infradead.org header.b="Q4mtK0tI"; dkim=fail reason="signature verification failed" (1024-bit key) header.d=kernel.org header.i=@kernel.org header.b="kSS5E+Wk" DMARC-Filter: OpenDMARC Filter v1.3.2 mail.kernel.org 9D1B920706 Authentication-Results: mail.kernel.org; dmarc=fail (p=none dis=none) header.from=kernel.org 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=merlin.20170209; h=Sender:Content-Type: Content-Transfer-Encoding:Cc:List-Subscribe:List-Help:List-Post:List-Archive: List-Unsubscribe:List-Id:Message-ID:References:In-Reply-To:Subject:To:From: Date:MIME-Version:Reply-To:Content-ID:Content-Description:Resent-Date: Resent-From:Resent-Sender:Resent-To:Resent-Cc:Resent-Message-ID:List-Owner; bh=4ndroHaKuL6iomXLDqMGyrjzIUNHkNa2vL6lJ3AGtX0=; b=Q4mtK0tIw3fJ5AdT00P7N6fBK 5leDckK+bXoo2abnEbAGmJs/mGXAcThkm3Bzu1iGz3ij3QrJ6cniFjcjoG2kl6fLFHqLN63+StVSW jVu1gkMldC1WoDYwqqxskHtOahgqsURn1AfxTOz2dBl8Qe/sh0S+P1rH2B2ZkWp4uc6XDsiiq6obT E44PSisKjNm7dnUylIONCGeeY2ggfzGfmM72uBJ6CkjT0BMTHIFCyYWBL/tjM7O2AjX8OMi8tkkPo IhxmaY05nT8gVMj/YBhWiTd6Ux1JJ3tbywGYSzwbWSvwW0EQC/AvRjWf2iwXE7Mr/6WKDBnJWuLQu ODQafnOpQ==; Received: from localhost ([::1] helo=merlin.infradead.org) by merlin.infradead.org with esmtp (Exim 4.92.3 #3 (Red Hat Linux)) id 1kjlHr-0001wf-Nh; Mon, 30 Nov 2020 15:40:23 +0000 Received: from mail.kernel.org ([198.145.29.99]) by merlin.infradead.org with esmtps (Exim 4.92.3 #3 (Red Hat Linux)) id 1kjlHn-0001vX-K1 for linux-arm-kernel@lists.infradead.org; Mon, 30 Nov 2020 15:40:20 +0000 Received: from disco-boy.misterjones.org (disco-boy.misterjones.org [51.254.78.96]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by mail.kernel.org (Postfix) with ESMTPSA id 5F880206C0; Mon, 30 Nov 2020 15:40:18 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=default; t=1606750818; bh=xvn4o/Ps2MmjI/dRiv8oM22Yyzf+9XlrLVdNZNcgBko=; h=Date:From:To:Cc:Subject:In-Reply-To:References:From; b=kSS5E+WkPTc5oeXpPcINZm3eSBnDfvMq4J4iFv4rFWgZE78tctxrEWiefyOS7HuLy RIanrltHcrVOvGM/Tc+oyVthAQAS0lEOEmZAcg7+U0L8R7oL2yr3PXWF2pNi/Rzmjm WDvG8Hbkk7BplkrnRgmyn4gSEjGfR2v17P2sLvLU= Received: from disco-boy.misterjones.org ([51.254.78.96] helo=www.loen.fr) by disco-boy.misterjones.org with esmtpsa (TLS1.2) tls TLS_ECDHE_RSA_WITH_AES_128_GCM_SHA256 (Exim 4.94) (envelope-from ) id 1kjlHk-00Ejeo-7O; Mon, 30 Nov 2020 15:40:16 +0000 MIME-Version: 1.0 Date: Mon, 30 Nov 2020 15:40:16 +0000 From: Marc Zyngier To: David Brazdil Subject: Re: [PATCH 2/2] KVM: arm64: Advertise ID_AA64PFR0_EL1.CSV3=1 if the CPUs are Meltdown-safe In-Reply-To: <20201130152655.oyzs2l4qg2pfzxmv@google.com> References: <20201128124659.669578-1-maz@kernel.org> <20201128124659.669578-3-maz@kernel.org> <20201130152655.oyzs2l4qg2pfzxmv@google.com> User-Agent: Roundcube Webmail/1.4.9 Message-ID: <4a398347b173c5c1a7a0ebd4b54a64bd@kernel.org> X-Sender: maz@kernel.org X-SA-Exim-Connect-IP: 51.254.78.96 X-SA-Exim-Rcpt-To: dbrazdil@google.com, linux-arm-kernel@lists.infradead.org, kvmarm@lists.cs.columbia.edu, kvm@vger.kernel.org, will@kernel.org, james.morse@arm.com, julien.thierry.kdev@gmail.com, suzuki.poulose@arm.com, kernel-team@android.com X-SA-Exim-Mail-From: maz@kernel.org X-SA-Exim-Scanned: No (on disco-boy.misterjones.org); SAEximRunCond expanded to false X-CRM114-Version: 20100106-BlameMichelson ( TRE 0.8.0 (BSD) ) MR-646709E3 X-CRM114-CacheID: sfid-20201130_104020_124301_BD1A9C51 X-CRM114-Status: GOOD ( 13.32 ) 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: kvm@vger.kernel.org, Suzuki K Poulose , kernel-team@android.com, James Morse , linux-arm-kernel@lists.infradead.org, Will Deacon , kvmarm@lists.cs.columbia.edu, Julien Thierry Content-Transfer-Encoding: 7bit Content-Type: text/plain; charset="us-ascii"; Format="flowed" Sender: "linux-arm-kernel" Errors-To: linux-arm-kernel-bounces+linux-arm-kernel=archiver.kernel.org@lists.infradead.org Hi David, On 2020-11-30 15:26, David Brazdil wrote: >> @@ -1227,9 +1229,16 @@ static int set_id_aa64pfr0_el1(struct kvm_vcpu >> *vcpu, >> (csv2 && arm64_get_spectre_v2_state() != SPECTRE_UNAFFECTED)) >> return -EINVAL; >> >> - /* We can only differ with CSV2, and anything else is an error */ >> + /* Same thing for CSV3 */ >> + csv3 = cpuid_feature_extract_unsigned_field(val, >> ID_AA64PFR0_CSV3_SHIFT); >> + if (csv3 > 1 || >> + (csv3 && arm64_get_meltdown_state() != SPECTRE_UNAFFECTED)) >> + return -EINVAL; >> + >> + /* We can only differ with CSV[23], and anything else is an error */ >> val ^= read_id_reg(vcpu, rd, false); >> - val &= ~(0xFUL << ID_AA64PFR0_CSV2_SHIFT); >> + val &= ~((0xFUL << ID_AA64PFR0_CSV2_SHIFT) || >> + (0xFUL << ID_AA64PFR0_CSV3_SHIFT)); > > That boolean OR looks like a typo. It definitely is. Who the hell is writing this code? Thanks, M. -- Jazz is not dead. It just smells funny... _______________________________________________ linux-arm-kernel mailing list linux-arm-kernel@lists.infradead.org http://lists.infradead.org/mailman/listinfo/linux-arm-kernel