From mboxrd@z Thu Jan 1 00:00:00 1970 From: Pierre Morel Subject: Re: [PATCH v3 2/3] KVM: s390: vsie: Do the CRYCB validation first Date: Thu, 23 Aug 2018 13:39:04 +0200 Message-ID: <33decece-3b10-0baf-9122-8ea76a65101a@linux.ibm.com> References: <1535019956-23539-1-git-send-email-pmorel@linux.ibm.com> <1535019956-23539-3-git-send-email-pmorel@linux.ibm.com> Reply-To: pmorel@linux.ibm.com Mime-Version: 1.0 Content-Type: text/plain; charset=utf-8; format=flowed Content-Transfer-Encoding: 8bit Cc: linux-kernel@vger.kernel.org, cohuck@redhat.com, linux-s390@vger.kernel.org, kvm@vger.kernel.org, frankja@linux.ibm.com, akrowiak@linux.ibm.com, schwidefsky@de.ibm.com, heiko.carstens@de.ibm.com To: Christian Borntraeger , david@redhat.com Return-path: In-Reply-To: Content-Language: en-US Sender: linux-kernel-owner@vger.kernel.org List-Id: kvm.vger.kernel.org On 23/08/2018 13:17, Christian Borntraeger wrote: > > > On 08/23/2018 12:25 PM, Pierre Morel wrote: >> When entering the SIE the CRYCB validation better >> be done independently of the instruction's >> availability. > > Maybe something like > > We need to handle the validity checks for the crycb, no matter what the > settings for the keywrappings are. So lets move the keywrapping checks > after we have done the validy checks. > > ? OK thanks, I use this. regards, Pierre > >> >> Signed-off-by: Pierre Morel >> --- >> arch/s390/kvm/vsie.c | 11 ++++++----- >> 1 file changed, 6 insertions(+), 5 deletions(-) >> >> diff --git a/arch/s390/kvm/vsie.c b/arch/s390/kvm/vsie.c >> index 12b9707..38ea5da 100644 >> --- a/arch/s390/kvm/vsie.c >> +++ b/arch/s390/kvm/vsie.c >> @@ -161,17 +161,18 @@ static int shadow_crycb(struct kvm_vcpu *vcpu, struct vsie_page *vsie_page) >> /* format-1 is supported with message-security-assist extension 3 */ >> if (!test_kvm_facility(vcpu->kvm, 76)) >> return 0; >> - /* we may only allow it if enabled for guest 2 */ >> - ecb3_flags = scb_o->ecb3 & vcpu->arch.sie_block->ecb3 & >> - (ECB3_AES | ECB3_DEA); >> - if (!ecb3_flags) >> - return 0; >> >> if ((crycb_addr & PAGE_MASK) != ((crycb_addr + 128) & PAGE_MASK)) >> return set_validity_icpt(scb_s, 0x003CU); >> else if (!crycb_addr) >> return set_validity_icpt(scb_s, 0x0039U); >> >> + /* we may only allow it if enabled for guest 2 */ >> + ecb3_flags = scb_o->ecb3 & vcpu->arch.sie_block->ecb3 & >> + (ECB3_AES | ECB3_DEA); >> + if (!ecb3_flags) >> + return 0; >> + >> /* copy only the wrapping keys */ >> if (read_guest_real(vcpu, crycb_addr + 72, >> vsie_page->crycb.dea_wrapping_key_mask, 56)) >> -- Pierre Morel Linux/KVM/QEMU in Böblingen - Germany