From ded13fc11b71fd1351e57c68a130d89a0285f1b6 Mon Sep 17 00:00:00 2001 From: Paul Mackerras Date: Wed, 22 Nov 2017 14:38:53 +1100 Subject: KVM: PPC: Book3S HV: Fix migration and HPT resizing of HPT guests on radix hosts This fixes two errors that prevent a guest using the HPT MMU from successfully migrating to a POWER9 host in radix MMU mode, or resizing its HPT when running on a radix host. The first bug was that commit 8dc6cca556e4 ("KVM: PPC: Book3S HV: Don't rely on host's page size information", 2017-09-11) missed two uses of hpte_base_page_size(), one in the HPT rehashing code and one in kvm_htab_write() (which is used on the destination side in migrating a HPT guest). Instead we use kvmppc_hpte_base_page_shift(). Having the shift count means that we can use left and right shifts instead of multiplication and division in a few places. Along the way, this adds a check in kvm_htab_write() to ensure that the page size encoding in the incoming HPTEs is recognized, and if not return an EINVAL error to userspace. The second bug was that kvm_htab_write was performing some but not all of the functions of kvmhv_setup_mmu(), resulting in the destination VM being left in radix mode as far as the hardware is concerned. The simplest fix for now is make kvm_htab_write() call kvmppc_setup_partition_table() like kvmppc_hv_setup_htab_rma() does. In future it would be better to refactor the code more extensively to remove the duplication. Fixes: 8dc6cca556e4 ("KVM: PPC: Book3S HV: Don't rely on host's page size information") Fixes: 7a84084c6054 ("KVM: PPC: Book3S HV: Set partition table rather than SDR1 on POWER9") Reported-by: Suraj Jitindar Singh Tested-by: Suraj Jitindar Singh Signed-off-by: Paul Mackerras --- arch/powerpc/include/asm/kvm_ppc.h | 1 + 1 file changed, 1 insertion(+) (limited to 'arch/powerpc/include/asm/kvm_ppc.h') diff --git a/arch/powerpc/include/asm/kvm_ppc.h b/arch/powerpc/include/asm/kvm_ppc.h index 96753f3aac6d..941c2a3f231b 100644 --- a/arch/powerpc/include/asm/kvm_ppc.h +++ b/arch/powerpc/include/asm/kvm_ppc.h @@ -180,6 +180,7 @@ extern void kvm_spapr_tce_release_iommu_group(struct kvm *kvm, struct iommu_group *grp); extern int kvmppc_switch_mmu_to_hpt(struct kvm *kvm); extern int kvmppc_switch_mmu_to_radix(struct kvm *kvm); +extern void kvmppc_setup_partition_table(struct kvm *kvm); extern long kvm_vm_ioctl_create_spapr_tce(struct kvm *kvm, struct kvm_create_spapr_tce_64 *args); -- cgit v1.2.3