Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1753814AbaKXP2t (ORCPT ); Mon, 24 Nov 2014 10:28:49 -0500 Received: from mail-wi0-f181.google.com ([209.85.212.181]:34641 "EHLO mail-wi0-f181.google.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1752915AbaKXP2r convert rfc822-to-8bit (ORCPT ); Mon, 24 Nov 2014 10:28:47 -0500 Content-Type: text/plain; charset=utf-8 Mime-Version: 1.0 (Mac OS X Mail 8.1 \(1993\)) Subject: Re: [CFT PATCH 0/2] KVM: support XSAVES usage in the host From: Nadav Amit In-Reply-To: <547318E5.8070408@redhat.com> Date: Mon, 24 Nov 2014 17:28:41 +0200 Cc: Linux Kernel Mailing List , kvm list , Nadav Amit , Wanpeng Li Content-Transfer-Encoding: 8BIT Message-Id: References: <1416594678-13011-1-git-send-email-pbonzini@redhat.com> <547318E5.8070408@redhat.com> To: Paolo Bonzini X-Mailer: Apple Mail (2.1993) Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org > On Nov 24, 2014, at 13:39, Paolo Bonzini wrote: > > > > On 23/11/2014 09:16, Nadav Amit wrote: >> I’ll try to check it tomorrow (I don’t have access to the failing machine at the moment). > > Thanks, you'll need to squash this in: > > diff --git a/arch/x86/kernel/xsave.c b/arch/x86/kernel/xsave.c > index 4c540c4719d8..0de1fae2bdf0 100644 > --- a/arch/x86/kernel/xsave.c > +++ b/arch/x86/kernel/xsave.c > @@ -738,3 +738,4 @@ void *get_xsave_addr(struct xsave_struct *xsave, int xstate) > > return (void *)xsave + xstate_comp_offsets[feature]; > } > +EXPORT_SYMBOL_GPL(get_xsave_addr); I tested the patches but there are still problems. Since kvm_load_guest_fpu is called before the guest_fpu is ever stored, there are 2 more problems that currently cause #GP: 1. XCOMP_BV[63] = 0 2. XSTATE_BV sets a bit (including bit 63) that is not set in XCOMP_BV (XCOMP_BV is initialised to zero). [see SDM 13.11 "OPERATION OF XRSTORS”] Once I initialise XCOMP_BV to (1ull << 63) | XSTATE_BV, the guest runs successfully. I have not checked any other qemu functionality that might be affected by the patch. Nadav -- To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to majordomo@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/