Hi Gavin, FYI, this has been fixed by Marc in commit 262b003d059c. Thanks, Keqian On 2021/3/15 12:18, Gavin Shan wrote: > The last (IPA) page can't be specified when a new memory slot is > added. The error -EFAULT is returned when the memory slot is added > with the following parameters for the VM, which has 40-bits IPA > limit. The host has 4KB base page size. It's not correct because > the last (IPA) page is still usable. > > struct kvm_userspace_memory_region { > __u32 slot; /* 1 */ > __u32 flags; /* 0 */ > __u64 guest_phys_addr; /* 0xfffffff000 */ > __u64 memory_size; /* 0x1000 */ > __u64 userspace_addr; > }; > > Signed-off-by: Gavin Shan <gshan@xxxxxxxxxx> > --- > arch/arm64/kvm/mmu.c | 2 +- > 1 file changed, 1 insertion(+), 1 deletion(-) > > diff --git a/arch/arm64/kvm/mmu.c b/arch/arm64/kvm/mmu.c > index 286b603ed0d3..a5a8ade9fde4 100644 > --- a/arch/arm64/kvm/mmu.c > +++ b/arch/arm64/kvm/mmu.c > @@ -1313,7 +1313,7 @@ int kvm_arch_prepare_memory_region(struct kvm *kvm, > * Prevent userspace from creating a memory region outside of the IPA > * space addressable by the KVM guest IPA space. > */ > - if (memslot->base_gfn + memslot->npages >= > + if (memslot->base_gfn + memslot->npages > > (kvm_phys_size(kvm) >> PAGE_SHIFT)) > return -EFAULT; > > _______________________________________________ kvmarm mailing list kvmarm@xxxxxxxxxxxxxxxxxxxxx https://lists.cs.columbia.edu/mailman/listinfo/kvmarm