On 05.06.19 01:25, Sasha Levin wrote: > From: Christian Borntraeger <[email protected]> > > [ Upstream commit 19ec166c3f39fe1d3789888a74cc95544ac266d4 ] > > kselftests exposed a problem in the s390 handling for memory slots. > Right now we only do proper memory slot handling for creation of new > memory slots. Neither MOVE, nor DELETION are handled properly. Let us > implement those.
I gave this a quick spin on 4.4.y and it seems to work fine. > > Signed-off-by: Christian Borntraeger <[email protected]> > Signed-off-by: Paolo Bonzini <[email protected]> > Signed-off-by: Sasha Levin <[email protected]> > --- > arch/s390/kvm/kvm-s390.c | 35 +++++++++++++++++++++-------------- > 1 file changed, 21 insertions(+), 14 deletions(-) > > diff --git a/arch/s390/kvm/kvm-s390.c b/arch/s390/kvm/kvm-s390.c > index 5ddb1debba95..23911ecfbad6 100644 > --- a/arch/s390/kvm/kvm-s390.c > +++ b/arch/s390/kvm/kvm-s390.c > @@ -2721,21 +2721,28 @@ void kvm_arch_commit_memory_region(struct kvm *kvm, > const struct kvm_memory_slot *new, > enum kvm_mr_change change) > { > - int rc; > - > - /* If the basics of the memslot do not change, we do not want > - * to update the gmap. Every update causes several unnecessary > - * segment translation exceptions. This is usually handled just > - * fine by the normal fault handler + gmap, but it will also > - * cause faults on the prefix page of running guest CPUs. > - */ > - if (old->userspace_addr == mem->userspace_addr && > - old->base_gfn * PAGE_SIZE == mem->guest_phys_addr && > - old->npages * PAGE_SIZE == mem->memory_size) > - return; > + int rc = 0; > > - rc = gmap_map_segment(kvm->arch.gmap, mem->userspace_addr, > - mem->guest_phys_addr, mem->memory_size); > + switch (change) { > + case KVM_MR_DELETE: > + rc = gmap_unmap_segment(kvm->arch.gmap, old->base_gfn * > PAGE_SIZE, > + old->npages * PAGE_SIZE); > + break; > + case KVM_MR_MOVE: > + rc = gmap_unmap_segment(kvm->arch.gmap, old->base_gfn * > PAGE_SIZE, > + old->npages * PAGE_SIZE); > + if (rc) > + break; > + /* FALLTHROUGH */ > + case KVM_MR_CREATE: > + rc = gmap_map_segment(kvm->arch.gmap, mem->userspace_addr, > + mem->guest_phys_addr, mem->memory_size); > + break; > + case KVM_MR_FLAGS_ONLY: > + break; > + default: > + WARN(1, "Unknown KVM MR CHANGE: %d\n", change); > + } > if (rc) > pr_warn("failed to commit memory region\n"); > return; >
