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charset=us-ascii Content-Disposition: inline In-Reply-To: <20250819215156.2494305-2-smostafa@google.com> X-BeenThere: linux-arm-kernel@lists.infradead.org X-Mailman-Version: 2.1.34 Precedence: list List-Id: List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Sender: "linux-arm-kernel" Errors-To: linux-arm-kernel-bounces+linux-arm-kernel=archiver.kernel.org@lists.infradead.org On Tue, Aug 19, 2025 at 09:51:29PM +0000, Mostafa Saleh wrote: > Soon, IOMMU drivers running in the hypervisor might interact with > non-coherent devices, so it needs a mechanism to map memory as > non cacheable. > Add ___pkvm_host_donate_hyp() which accepts a new argument for prot, > so the driver can add KVM_PGTABLE_PROT_NORMAL_NC. > > Signed-off-by: Mostafa Saleh > --- > arch/arm64/kvm/hyp/include/nvhe/mem_protect.h | 1 + > arch/arm64/kvm/hyp/nvhe/mem_protect.c | 11 +++++++++-- > 2 files changed, 10 insertions(+), 2 deletions(-) > > diff --git a/arch/arm64/kvm/hyp/include/nvhe/mem_protect.h b/arch/arm64/kvm/hyp/include/nvhe/mem_protect.h > index 5f9d56754e39..52d7ee91e18c 100644 > --- a/arch/arm64/kvm/hyp/include/nvhe/mem_protect.h > +++ b/arch/arm64/kvm/hyp/include/nvhe/mem_protect.h > @@ -36,6 +36,7 @@ int __pkvm_prot_finalize(void); > int __pkvm_host_share_hyp(u64 pfn); > int __pkvm_host_unshare_hyp(u64 pfn); > int __pkvm_host_donate_hyp(u64 pfn, u64 nr_pages); > +int ___pkvm_host_donate_hyp(u64 pfn, u64 nr_pages, enum kvm_pgtable_prot prot); > int __pkvm_hyp_donate_host(u64 pfn, u64 nr_pages); > int __pkvm_host_share_ffa(u64 pfn, u64 nr_pages); > int __pkvm_host_unshare_ffa(u64 pfn, u64 nr_pages); > diff --git a/arch/arm64/kvm/hyp/nvhe/mem_protect.c b/arch/arm64/kvm/hyp/nvhe/mem_protect.c > index 8957734d6183..861e448183fd 100644 > --- a/arch/arm64/kvm/hyp/nvhe/mem_protect.c > +++ b/arch/arm64/kvm/hyp/nvhe/mem_protect.c > @@ -769,13 +769,15 @@ int __pkvm_host_unshare_hyp(u64 pfn) > return ret; > } > > -int __pkvm_host_donate_hyp(u64 pfn, u64 nr_pages) > +int ___pkvm_host_donate_hyp(u64 pfn, u64 nr_pages, enum kvm_pgtable_prot prot) > { > u64 phys = hyp_pfn_to_phys(pfn); > u64 size = PAGE_SIZE * nr_pages; > void *virt = __hyp_va(phys); > int ret; > > + WARN_ON(prot & KVM_PGTABLE_PROT_X); Should this actually just enforce that the permissions are KVM_PGTABLE_PROT_RW: WARN_ON((prot & KVM_PGTABLE_PROT_RWX) != KVM_PGTABLE_PROT_RW); ? Since the motivation is about the memory type rather than the permissions, it would be best to preserve the current behaviour. Will