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charset="UTF-8" From: Ackerley Tng Update the KVM MMU fault handler to service guest page faults for memory slots backed by guest_memfd with mmap support. For such slots, the MMU must always fault in pages directly from guest_memfd, bypassing the host's userspace_addr. This ensures that guest_memfd-backed memory is always handled through the guest_memfd specific faulting path, regardless of whether it's for private or non-private (shared) use cases. Additionally, rename kvm_mmu_faultin_pfn_private() to kvm_mmu_faultin_pfn_gmem(), as this function is now used to fault in pages from guest_memfd for both private and non-private memory, accommodating the new use cases. Co-developed-by: David Hildenbrand Signed-off-by: David Hildenbrand Signed-off-by: Ackerley Tng Co-developed-by: Fuad Tabba Signed-off-by: Fuad Tabba --- arch/x86/kvm/mmu/mmu.c | 13 +++++++++---- 1 file changed, 9 insertions(+), 4 deletions(-) diff --git a/arch/x86/kvm/mmu/mmu.c b/arch/x86/kvm/mmu/mmu.c index 94be15cde6da..ad5f337b496c 100644 --- a/arch/x86/kvm/mmu/mmu.c +++ b/arch/x86/kvm/mmu/mmu.c @@ -4511,8 +4511,8 @@ static void kvm_mmu_finish_page_fault(struct kvm_vcpu *vcpu, r == RET_PF_RETRY, fault->map_writable); } -static int kvm_mmu_faultin_pfn_private(struct kvm_vcpu *vcpu, - struct kvm_page_fault *fault) +static int kvm_mmu_faultin_pfn_gmem(struct kvm_vcpu *vcpu, + struct kvm_page_fault *fault) { int max_order, r; @@ -4536,13 +4536,18 @@ static int kvm_mmu_faultin_pfn_private(struct kvm_vcpu *vcpu, return RET_PF_CONTINUE; } +static bool fault_from_gmem(struct kvm_page_fault *fault) +{ + return fault->is_private || kvm_memslot_is_gmem_only(fault->slot); +} + static int __kvm_mmu_faultin_pfn(struct kvm_vcpu *vcpu, struct kvm_page_fault *fault) { unsigned int foll = fault->write ? FOLL_WRITE : 0; - if (fault->is_private) - return kvm_mmu_faultin_pfn_private(vcpu, fault); + if (fault_from_gmem(fault)) + return kvm_mmu_faultin_pfn_gmem(vcpu, fault); foll |= FOLL_NOWAIT; fault->pfn = __kvm_faultin_pfn(fault->slot, fault->gfn, foll, -- 2.50.0.727.gbf7dc18ff4-goog