From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from eggs.gnu.org ([2001:4830:134:3::10]:43571) by lists.gnu.org with esmtp (Exim 4.71) (envelope-from ) id 1fddp8-0008T8-RK for qemu-devel@nongnu.org; Thu, 12 Jul 2018 11:48:07 -0400 Received: from Debian-exim by eggs.gnu.org with spam-scanned (Exim 4.71) (envelope-from ) id 1fddp8-0005OC-41 for qemu-devel@nongnu.org; Thu, 12 Jul 2018 11:48:06 -0400 Received: from mx3-rdu2.redhat.com ([66.187.233.73]:57938 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 1fddp7-0005Nk-Ul for qemu-devel@nongnu.org; Thu, 12 Jul 2018 11:48:06 -0400 References: <1530098844-236851-1-git-send-email-robert.hu@linux.intel.com> <1530098844-236851-3-git-send-email-robert.hu@linux.intel.com> <20180628182820.GE914@localhost.localdomain> <1530603313.22880.36.camel@linux.intel.com> <20180703110007.GL7451@localhost.localdomain> <1531387131.78672.1.camel@linux.intel.com> From: Paolo Bonzini Message-ID: Date: Thu, 12 Jul 2018 17:47:57 +0200 MIME-Version: 1.0 In-Reply-To: <1531387131.78672.1.camel@linux.intel.com> Content-Type: text/plain; charset=utf-8 Content-Language: en-US Content-Transfer-Encoding: 7bit Subject: Re: [Qemu-devel] [PATCH v2 2/5] i386: Add CPUID bit and feature words for IA32_ARCH_CAPABILITIES MSR List-Id: List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , To: Robert Hoo , Eduardo Habkost Cc: robert.hu@intel.com, qemu-devel@nongnu.org, rth@twiddle.net On 12/07/2018 11:18, Robert Hoo wrote: >>> And you'd like to set IA32_ARCH_CAPABILITIES.RSBA by default in qemu or >>> kvm layer? >> Probably we need to make this decision in QEMU. If KVM set RSBA >> automatically on .get_msr_feature(), QEMU won't be able to >> differentiate a host with RSBA set from a host with RSBA unset. >> > What's the default value for MSR IA32_ARCH_CAPABILITIES? is it clear > now? > It's the host value. However, QEMU never sets the CPUID bit so it doesn't matter if you are using QEMU. Paolo