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/kvm/book3s_hv.c | 3 +-- 1 file changed, 1 insertion(+), 2 deletions(-) (limited to 'arch/powerpc/kvm/book3s_hv.c') diff --git a/arch/powerpc/kvm/book3s_hv.c b/arch/powerpc/kvm/book3s_hv.c index 79ea3d9269db..2d46037ce936 100644 --- a/arch/powerpc/kvm/book3s_hv.c +++ b/arch/powerpc/kvm/book3s_hv.c @@ -120,7 +120,6 @@ MODULE_PARM_DESC(h_ipi_redirect, "Redirect H_IPI wakeup to a free host core"); static void kvmppc_end_cede(struct kvm_vcpu *vcpu); static int kvmppc_hv_setup_htab_rma(struct kvm_vcpu *vcpu); -static void kvmppc_setup_partition_table(struct kvm *kvm); static inline struct kvm_vcpu *next_runnable_thread(struct kvmppc_vcore *vc, int *ip) @@ -3574,7 +3573,7 @@ static void kvmppc_mmu_destroy_hv(struct kvm_vcpu *vcpu) return; } -static void kvmppc_setup_partition_table(struct kvm *kvm) +void kvmppc_setup_partition_table(struct kvm *kvm) { unsigned long dw0, dw1; -- cgit v1.2.3