From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from eggs.gnu.org ([2001:4830:134:3::10]:37743) by lists.gnu.org with esmtp (Exim 4.71) (envelope-from ) id 1fXk9H-0003TF-RW for qemu-devel@nongnu.org; Tue, 26 Jun 2018 05:20:32 -0400 Received: from Debian-exim by eggs.gnu.org with spam-scanned (Exim 4.71) (envelope-from ) id 1fXk9E-0000ps-9s for qemu-devel@nongnu.org; Tue, 26 Jun 2018 05:20:31 -0400 Received: from mx3-rdu2.redhat.com ([66.187.233.73]:57992 helo=mx1.redhat.com) by eggs.gnu.org with esmtps (TLS1.0:DHE_RSA_AES_256_CBC_SHA1:32) (Exim 4.71) (envelope-from ) id 1fXk9E-0000pk-36 for qemu-devel@nongnu.org; Tue, 26 Jun 2018 05:20:28 -0400 References: <1529897961-134132-1-git-send-email-robert.hu@linux.intel.com> <1529897961-134132-2-git-send-email-robert.hu@linux.intel.com> <03c394d5-6099-2f59-2dbf-c92b54281e91@redhat.com> <1530003511.22880.5.camel@linux.intel.com> From: Paolo Bonzini Message-ID: Date: Tue, 26 Jun 2018 11:20:23 +0200 MIME-Version: 1.0 In-Reply-To: <1530003511.22880.5.camel@linux.intel.com> Content-Type: text/plain; charset=utf-8 Content-Language: en-US Content-Transfer-Encoding: 7bit Subject: Re: [Qemu-devel] [PATCH 1/5] i386: Add support for IA32_PRED_CMD and IA32_ARCH_CAPABILITIES MSRs List-Id: List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , To: Robert Hoo Cc: qemu-devel@nongnu.org, rth@twiddle.net, ehabkost@redhat.com On 26/06/2018 10:58, Robert Hoo wrote: >> This is not needed, because pred_cmd is write only and arch_capabilities >> is read only. The guest cannot modify any of them. >> > Thanks Paolo. Yes, indeed unnecessary. > I looked into the > 336996-Speculative-Execution-Side-Channel-Mitigations.pdf again, looks > like the vmstate_spec_ctrl is similar to pred_cmd, wirte only. Shall I > remove it as well in v2 patch? No, spec_ctrl is read-write. Paolo