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Peter Anvin" , Peter Zijlstra , Ingo Molnar , Arnaldo Carvalho de Melo , Namhyung Kim , Paolo Bonzini , Thomas Gleixner , Borislav Petkov , Josh Poimboeuf , Jarkko Sakkinen , Vitaly Kuznetsov , Dave Hansen , "Kirill A. Shutemov" , Halil Pasic , Jason Herne , Harald Freudenberger , Holger Dengler Cc: linuxppc-dev@lists.ozlabs.org, kvm@vger.kernel.org, linux-kernel@vger.kernel.org, linux-perf-users@vger.kernel.org, linux-sgx@vger.kernel.org, x86@kernel.org, linux-coco@lists.linux.dev, linux-s390@vger.kernel.org References: <20250729174238.593070-1-seanjc@google.com> <20250729174238.593070-2-seanjc@google.com> Content-Language: en-US From: Anthony Krowiak In-Reply-To: <20250729174238.593070-2-seanjc@google.com> Content-Type: text/plain; charset=UTF-8; format=flowed Content-Transfer-Encoding: 7bit X-TM-AS-GCONF: 00 X-Proofpoint-GUID: wUyLy7r54uq5s4N33KjtyxxIF6IG3KA9 X-Proofpoint-Spam-Details-Enc: AW1haW4tMjUwODEyMDE4NiBTYWx0ZWRfX7aP/l7ZcVtZa dZX9+xrlp4zkFuGVW4392P+pol6seqW/hahqEiQqy5LqXmJIftaeIAqDiK6lxM08bCcVJRcLLS9 ON2guFIKLHia+Q7PMxonf8VSge5GnRjyY+1rMpAybUP2cAGqNwT+R1ifllolXCTsDJOHI4FQp9q /DKo36tMXVC/xVIEGIeOVRnGqt2DCHyaBP9vFHFeNCPpFbLVXEdIXt1isSmG/aUmAsqqYSNkqzq jXASDGRHh3KryL9EGDcD1vu3eW2VGvuMiovWzjjmO6J8d6oE6clCyLvuLbf2Uvw8wJSNDkm6hh/ sE1YPL1lgeMCkjw/iqJO933TO4RUCTm+R3Gi70kvErflhOFpG3+J2MNomx960M1O6hVLlnKSEpJ EZAAblAxhsKNGkn+v8tAv1QyuzdhnrlXxv/x/ezGWnM72keyIESm9hZybrHQYh2UjwixLv1X X-Authority-Analysis: v=2.4 cv=QtNe3Uyd c=1 sm=1 tr=0 ts=689b98c5 cx=c_pps a=aDMHemPKRhS1OARIsFnwRA==:117 a=aDMHemPKRhS1OARIsFnwRA==:17 a=IkcTkHD0fZMA:10 a=2OwXVqhp2XgA:10 a=1XWaLZrsAAAA:8 a=VnNF1IyMAAAA:8 a=WMn4R6eJaF8VgN3aVUEA:9 a=QEXdDO2ut3YA:10 X-Proofpoint-ORIG-GUID: PGtZzgNN4fjfj6Pu373XoqOssQ1e8xOb X-Proofpoint-Virus-Version: vendor=baseguard engine=ICAP:2.0.293,Aquarius:18.0.1099,Hydra:6.1.9,FMLib:17.12.80.40 definitions=2025-08-12_07,2025-08-11_01,2025-03-28_01 X-Proofpoint-Spam-Details: rule=outbound_notspam policy=outbound score=0 adultscore=0 priorityscore=1501 lowpriorityscore=0 clxscore=1011 mlxlogscore=999 impostorscore=0 suspectscore=0 bulkscore=0 mlxscore=0 phishscore=0 malwarescore=0 spamscore=0 classifier=spam authscore=0 authtc=n/a authcc= route=outbound adjust=0 reason=mlx scancount=1 engine=8.19.0-2507300000 definitions=main-2508120186 On 7/29/25 1:42 PM, Sean Christopherson wrote: > Use kvm_is_gpa_in_memslot() to check the validity of the notification > indicator byte address instead of open coding equivalent logic in the VFIO > AP driver. > > Opportunistically use a dedicated wrapper that exists and is exported > expressly for the VFIO AP module. kvm_is_gpa_in_memslot() is generally > unsuitable for use outside of KVM; other drivers typically shouldn't rely > on KVM's memslots, and using the API requires kvm->srcu (or slots_lock) to > be held for the entire duration of the usage, e.g. to avoid TOCTOU bugs. > handle_pqap() is a bit of a special case, as it's explicitly invoked from > KVM with kvm->srcu already held, and the VFIO AP driver is in many ways an > extension of KVM that happens to live in a separate module. > > Providing a dedicated API for the VFIO AP driver will allow restricting > the vast majority of generic KVM's exports to KVM submodules (e.g. to x86's > kvm-{amd,intel}.ko vendor mdoules). > > No functional change intended. > > Signed-off-by: Sean Christopherson Acked-by: Anthony Krowiak I only reviewed this patch in the series. > --- > arch/s390/include/asm/kvm_host.h | 2 ++ > arch/s390/kvm/priv.c | 8 ++++++++ > drivers/s390/crypto/vfio_ap_ops.c | 2 +- > 3 files changed, 11 insertions(+), 1 deletion(-) > > diff --git a/arch/s390/include/asm/kvm_host.h b/arch/s390/include/asm/kvm_host.h > index cb89e54ada25..449bc34e7cc3 100644 > --- a/arch/s390/include/asm/kvm_host.h > +++ b/arch/s390/include/asm/kvm_host.h > @@ -719,6 +719,8 @@ bool kvm_s390_pv_cpu_is_protected(struct kvm_vcpu *vcpu); > extern int kvm_s390_gisc_register(struct kvm *kvm, u32 gisc); > extern int kvm_s390_gisc_unregister(struct kvm *kvm, u32 gisc); > > +bool kvm_s390_is_gpa_in_memslot(struct kvm *kvm, gpa_t gpa); > + > static inline void kvm_arch_free_memslot(struct kvm *kvm, > struct kvm_memory_slot *slot) {} > static inline void kvm_arch_memslots_updated(struct kvm *kvm, u64 gen) {} > diff --git a/arch/s390/kvm/priv.c b/arch/s390/kvm/priv.c > index 9253c70897a8..7773e1e323bc 100644 > --- a/arch/s390/kvm/priv.c > +++ b/arch/s390/kvm/priv.c > @@ -605,6 +605,14 @@ static int handle_io_inst(struct kvm_vcpu *vcpu) > } > } > > +#if IS_ENABLED(CONFIG_VFIO_AP) > +bool kvm_s390_is_gpa_in_memslot(struct kvm *kvm, gpa_t gpa) > +{ > + return kvm_is_gpa_in_memslot(kvm, gpa); > +} > +EXPORT_SYMBOL_GPL_FOR_MODULES(kvm_s390_is_gpa_in_memslot, "vfio_ap"); > +#endif > + > /* > * handle_pqap: Handling pqap interception > * @vcpu: the vcpu having issue the pqap instruction > diff --git a/drivers/s390/crypto/vfio_ap_ops.c b/drivers/s390/crypto/vfio_ap_ops.c > index 766557547f83..eb5ff49f6fe7 100644 > --- a/drivers/s390/crypto/vfio_ap_ops.c > +++ b/drivers/s390/crypto/vfio_ap_ops.c > @@ -354,7 +354,7 @@ static int vfio_ap_validate_nib(struct kvm_vcpu *vcpu, dma_addr_t *nib) > > if (!*nib) > return -EINVAL; > - if (kvm_is_error_hva(gfn_to_hva(vcpu->kvm, *nib >> PAGE_SHIFT))) > + if (!kvm_s390_is_gpa_in_memslot(vcpu->kvm, *nib)) > return -EINVAL; > > return 0;