Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1752127AbbGPEKW (ORCPT ); Thu, 16 Jul 2015 00:10:22 -0400 Received: from mx1.redhat.com ([209.132.183.28]:34290 "EHLO mx1.redhat.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1751820AbbGPEKV (ORCPT ); Thu, 16 Jul 2015 00:10:21 -0400 Message-ID: <1437019818.1391.544.camel@redhat.com> Subject: Re: [PATCH 1/3] KVM: MTRR: fix memory type handling if MTRR is completely disabled From: Alex Williamson To: Xiao Guangrong Cc: pbonzini@redhat.com, gleb@kernel.org, mtosatti@redhat.com, kvm@vger.kernel.org, linux-kernel@vger.kernel.org, bsd@redhat.com, lersek@redhat.com, jordan.l.justen@intel.com, edk2-devel@lists.sourceforge.net, Xiao Guangrong Date: Wed, 15 Jul 2015 22:10:18 -0600 In-Reply-To: <1436988356-4565-1-git-send-email-guangrong.xiao@linux.intel.com> References: <1436988356-4565-1-git-send-email-guangrong.xiao@linux.intel.com> Content-Type: text/plain; charset="UTF-8" Mime-Version: 1.0 Content-Transfer-Encoding: 7bit Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Content-Length: 2729 Lines: 93 On Thu, 2015-07-16 at 03:25 +0800, Xiao Guangrong wrote: > From: Xiao Guangrong > > Currently code uses default memory type if MTRR is fully disabled, > fix it by using UC instead > > Signed-off-by: Xiao Guangrong > --- Seems to work for me. I don't see a 0th patch, but for the series: Tested-by: Alex Williamson Thanks! > arch/x86/kvm/mtrr.c | 21 ++++++++++++++++++++- > 1 file changed, 20 insertions(+), 1 deletion(-) > > diff --git a/arch/x86/kvm/mtrr.c b/arch/x86/kvm/mtrr.c > index de1d2d8..e275013 100644 > --- a/arch/x86/kvm/mtrr.c > +++ b/arch/x86/kvm/mtrr.c > @@ -120,6 +120,16 @@ static u8 mtrr_default_type(struct kvm_mtrr *mtrr_state) > return mtrr_state->deftype & IA32_MTRR_DEF_TYPE_TYPE_MASK; > } > > +static u8 mtrr_disabled_type(void) > +{ > + /* > + * Intel SDM 11.11.2.2: all MTRRs are disabled when > + * IA32_MTRR_DEF_TYPE.E bit is cleared, and the UC > + * memory type is applied to all of physical memory. > + */ > + return MTRR_TYPE_UNCACHABLE; > +} > + > /* > * Three terms are used in the following code: > * - segment, it indicates the address segments covered by fixed MTRRs. > @@ -434,6 +444,8 @@ struct mtrr_iter { > > /* output fields. */ > int mem_type; > + /* mtrr is completely disabled? */ > + bool mtrr_disabled; > /* [start, end) is not fully covered in MTRRs? */ > bool partial_map; > > @@ -549,7 +561,7 @@ static void mtrr_lookup_var_next(struct mtrr_iter *iter) > static void mtrr_lookup_start(struct mtrr_iter *iter) > { > if (!mtrr_is_enabled(iter->mtrr_state)) { > - iter->partial_map = true; > + iter->mtrr_disabled = true; > return; > } > > @@ -563,6 +575,7 @@ static void mtrr_lookup_init(struct mtrr_iter *iter, > iter->mtrr_state = mtrr_state; > iter->start = start; > iter->end = end; > + iter->mtrr_disabled = false; > iter->partial_map = false; > iter->fixed = false; > iter->range = NULL; > @@ -656,6 +669,9 @@ u8 kvm_mtrr_get_guest_memory_type(struct kvm_vcpu *vcpu, gfn_t gfn) > return MTRR_TYPE_WRBACK; > } > > + if (iter.mtrr_disabled) > + return mtrr_disabled_type(); > + > /* It is not covered by MTRRs. */ > if (iter.partial_map) { > /* > @@ -689,6 +705,9 @@ bool kvm_mtrr_check_gfn_range_consistency(struct kvm_vcpu *vcpu, gfn_t gfn, > return false; > } > > + if (iter.mtrr_disabled) > + return true; > + > if (!iter.partial_map) > return true; > -- 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/