From mboxrd@z Thu Jan 1 00:00:00 1970 From: Bandan Das Subject: [PATCH v2 4/5] mmu: change unconditional setting of the u bit in fault bitmap Date: Tue, 12 Jul 2016 18:18:51 -0400 Message-ID: <1468361932-16580-5-git-send-email-bsd@redhat.com> References: <1468361932-16580-1-git-send-email-bsd@redhat.com> Cc: pbonzini@redhat.com, guangrong.xiao@linux.intel.com, kernellwp@gmail.com, linux-kernel@vger.kernel.org To: kvm@vger.kernel.org Return-path: In-Reply-To: <1468361932-16580-1-git-send-email-bsd@redhat.com> Sender: linux-kernel-owner@vger.kernel.org List-Id: kvm.vger.kernel.org For the nested EPT case, we assume that the read bit (u) is always set since we used to unconditionally set it in set_spte(). Modify it to only be set when host ept execute only support isn't present. Signed-off-by: Bandan Das --- arch/x86/kvm/mmu.c | 7 ++++--- 1 file changed, 4 insertions(+), 3 deletions(-) diff --git a/arch/x86/kvm/mmu.c b/arch/x86/kvm/mmu.c index c364dcb..566eea5 100644 --- a/arch/x86/kvm/mmu.c +++ b/arch/x86/kvm/mmu.c @@ -3923,9 +3923,10 @@ static void update_permission_bitmask(struct kvm_vcpu *vcpu, * clearer. */ smap = cr4_smap && u && !uf && !ff; - } else - /* Not really needed: no U/S accesses on ept */ - u = 1; + } else { + if (shadow_present_mask) + u = 1; + } fault = (ff && !x) || (uf && !u) || (wf && !w) || (smapf && smap); -- 2.5.5