From mboxrd@z Thu Jan 1 00:00:00 1970 From: Paolo Bonzini Subject: Re: [PATCH] KVM: x86: don't expose syscall/sysret to intel 32-bit guest Date: Thu, 19 Nov 2015 13:02:40 +0100 Message-ID: <564DBA60.2010707@redhat.com> References: <564DACF5.9090908@redhat.com> Mime-Version: 1.0 Content-Type: text/plain; charset=windows-1252 Content-Transfer-Encoding: 7bit Cc: Wanpeng li , kvm , "linux-kernel@vger.kernel.org" To: Wanpeng Li Return-path: In-Reply-To: Sender: linux-kernel-owner@vger.kernel.org List-Id: kvm.vger.kernel.org On 19/11/2015 13:01, Wanpeng Li wrote: > > This is not correct. As far as I know, the SYSCALL bit is always > > present in CPUID, even if the machine is running in 32-bit mode; CPUID > > documentation (SDM Volume 2) explicitly documents bit 11 as "Bit 11: > > SYSCALL/SYSRET available in 64-bit mode". > > No, I try a 32-bit linux host kernel, cpuid tool shows that SYSCALL > bit is not set. Ok, let me try... Paolo