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=-15.8 required=3.0 tests=BAYES_00,DKIMWL_WL_HIGH, DKIM_SIGNED,DKIM_VALID,INCLUDES_CR_TRAILER,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 32201C433E0 for ; Tue, 9 Mar 2021 13:45:34 +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 A8E9064F69 for ; Tue, 9 Mar 2021 13:45:32 +0000 (UTC) DMARC-Filter: OpenDMARC Filter v1.3.2 mail.kernel.org A8E9064F69 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=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=1MfWBl7r9cTBdq/GPOfIVogrKW3dQVayww5nrGpP/L8=; b=biUQsWPpvWnxTNgaNzcmunzi1 a4/kdMda+2JWGx8pTsO15e/B2BseKLw/9BJVMuFDhVPoG8kQ3JH+IKpnKcDTlV1rVINOgWd3hUqqv 0EjwTPX0xPtHK2mnToVfxmAayfKqWl4QcYqEpnjwxoylDtNIYztUofKuVRGKKMXoOml/hXvuva7Ol vXCUaX6DT/S/TajGvDKvSCFHsfq3e9BUd2SIUAcxlmSRySUmVzKbj7aXySgG2d7FtIlcQGIlAbB1/ RIFLLz/v0eXiW9NQZ0bvBLXhhoflNuZrfo0ohWktVaW0H/wHyhkQWNeYXXNLrf9D1RsajR5qfthhk 3pzO4TziQ==; Received: from localhost ([::1] helo=desiato.infradead.org) by desiato.infradead.org with esmtp (Exim 4.94 #2 (Red Hat Linux)) id 1lJce4-004icM-Mz; Tue, 09 Mar 2021 13:43:33 +0000 Received: from mail.kernel.org ([198.145.29.99]) by desiato.infradead.org with esmtps (Exim 4.94 #2 (Red Hat Linux)) id 1lJcNz-004ceR-LC for linux-arm-kernel@lists.infradead.org; Tue, 09 Mar 2021 13:27:07 +0000 Received: by mail.kernel.org (Postfix) with ESMTPSA id BC30064D8F; Tue, 9 Mar 2021 13:26:49 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=k20201202; t=1615296411; bh=GW/0WIVybU+FKZci+pHzO6MpN/bNiJDrh5DoiKRhFGo=; h=Date:From:To:Cc:Subject:References:In-Reply-To:From; b=ZgLBDtYY4aIDeUHdlKwtssqYTc3uPuKrCzBJUYdtFYSrE1mQA2FiUxsEh6PX+DCf4 SQrAAhLsr6Pp5qvvgoyWI5P4OLszI7f7dBuIkSx/g4+tIbeXcBEwybscpR3BJXjbQe uuLsBFErYny4EmsPbJkucFL+VYcY/CxXovHyidKU0C44zYl+siFpQp82qsoH1JfME3 yLXglUMvBgDqhZde+oRzWHYWnMxUf700y8JIvPreQMpqzla1Pp6NDw1vvrqyb/+EKM RwbBN2UTIbmuxxZY2DTuX2F2tDTOh+5TY1tNK5oBp6Ot7+E4FgCnmeuhOulkcfjyBS +ndJVCHjsd5/A== Date: Tue, 9 Mar 2021 13:26:46 +0000 From: Will Deacon To: Marc Zyngier Cc: linux-arm-kernel@lists.infradead.org, kvmarm@lists.cs.columbia.edu, kvm@vger.kernel.org, kernel-team@android.com, James Morse , Julien Thierry , Suzuki K Poulose , Mark Rutland , Catalin Marinas , Alexandru Elisei Subject: Re: [PATCH] KVM: arm64: Ensure I-cache isolation between vcpus of a same VM Message-ID: <20210309132645.GA28297@willie-the-truck> References: <20210303164505.68492-1-maz@kernel.org> MIME-Version: 1.0 Content-Disposition: inline In-Reply-To: <20210303164505.68492-1-maz@kernel.org> User-Agent: Mutt/1.10.1 (2018-07-13) X-CRM114-Version: 20100106-BlameMichelson ( TRE 0.8.0 (BSD) ) MR-646709E3 X-CRM114-CacheID: sfid-20210309_132656_925581_A3EA0900 X-CRM114-Status: GOOD ( 18.83 ) 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 On Wed, Mar 03, 2021 at 04:45:05PM +0000, Marc Zyngier wrote: > It recently became apparent that the ARMv8 architecture has interesting > rules regarding attributes being used when fetching instructions > if the MMU is off at Stage-1. > > In this situation, the CPU is allowed to fetch from the PoC and > allocate into the I-cache (unless the memory is mapped with > the XN attribute at Stage-2). > > If we transpose this to vcpus sharing a single physical CPU, > it is possible for a vcpu running with its MMU off to influence > another vcpu running with its MMU on, as the latter is expected to > fetch from the PoU (and self-patching code doesn't flush below that > level). > > In order to solve this, reuse the vcpu-private TLB invalidation > code to apply the same policy to the I-cache, nuking it every time > the vcpu runs on a physical CPU that ran another vcpu of the same > VM in the past. > > This involve renaming __kvm_tlb_flush_local_vmid() to > __kvm_flush_cpu_context(), and inserting a local i-cache invalidation > there. > > Cc: stable@vger.kernel.org > Signed-off-by: Marc Zyngier > --- > arch/arm64/include/asm/kvm_asm.h | 4 ++-- > arch/arm64/kvm/arm.c | 7 ++++++- > arch/arm64/kvm/hyp/nvhe/hyp-main.c | 6 +++--- > arch/arm64/kvm/hyp/nvhe/tlb.c | 3 ++- > arch/arm64/kvm/hyp/vhe/tlb.c | 3 ++- > 5 files changed, 15 insertions(+), 8 deletions(-) Since the FWB discussion doesn't affect the correctness of this patch: Acked-by: Will Deacon Will _______________________________________________ linux-arm-kernel mailing list linux-arm-kernel@lists.infradead.org http://lists.infradead.org/mailman/listinfo/linux-arm-kernel