On Mon, Aug 18, 2014 at 03:30:58PM -0500, Joel Schopp wrote: > > #endif /* __ARM_KVM_MMU_H__ */ > diff --git a/arch/arm/kvm/mmu.c b/arch/arm/kvm/mmu.c > index 16e7994..70f0f02 100644 > --- a/arch/arm/kvm/mmu.c > +++ b/arch/arm/kvm/mmu.c > @@ -521,6 +521,7 @@ int create_hyp_io_mappings(void *from, void *to, phys_addr_t phys_addr) > */ > int kvm_alloc_stage2_pgd(struct kvm *kvm) > { > + unsigned int s2_pgds, s2_pgd_order; > pgd_t *pgd; > > if (kvm->arch.pgd != NULL) { > @@ -528,10 +529,18 @@ int kvm_alloc_stage2_pgd(struct kvm *kvm) > return -EINVAL; > } > > - pgd = (pgd_t *)__get_free_pages(GFP_KERNEL, S2_PGD_ORDER); > + s2_pgds = (1 << (kvm_get_phys_addr_shift() - PGDIR_SHIFT)); > + s2_pgd_order = get_order(s2_pgds * sizeof(pgd_t)); > + > + pgd = (pgd_t *)__get_free_pages(GFP_KERNEL, s2_pgd_order); > if (!pgd) > return -ENOMEM; > > + if ((unsigned long)pgd & ~vttbr_baddr_mask) { > + kvm_err("Stage-2 pgd not correctly aligned: %p\n", pgd); > + return -EFAULT; > + } > > > There are two problems that I've found here. The first problem is that > vttbr_baddr_mask isn't allocated yet at this point in the code. allocated? you mean assigned? aren't you setting vttbr_baddr_mask in kvm_arch_init()? that's certainly called before kvm_arch_init_vm(). > The > second problem is that pgd is a virtual address, ie pgd == > 0xfffffe03bbb40000 while the vttbr masks off the high bits for a > physical address, ie vttbr_baddr_mask=0x00007ffffffe0000 . Even > correcting for those issues I haven't been able to make this check work > properly. I'll resend v5 the patch with all the other suggested changes. > What are the issues that you face? Iow. what is the alignment of the returned physical address? (You should be able to just to virt_to_phys(pgd) and use that to test for the vttbr_baddr_mask). Thanks, -Christoffer -- To unsubscribe from this list: send the line "unsubscribe kvm" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html