On Thu, 17 Jan 2019 21:53:16 +0000 "Singh, Brijesh" <brijesh.si...@amd.com> wrote:
> The RAM device presents a memory region that should be handled > as an IO region and should not be pinned. > > In the case of the vfio-pci, RAM device represents a MMIO BAR > and the memory region is not backed by pages hence > KVM_MEMORY_ENCRYPT_REG_REGION fails to lock the memory range. > > Fixes: https://bugzilla.redhat.com/show_bug.cgi?id=1667249 > Cc: Alex Williamson <alex.william...@redhat.com> > Cc: Paolo Bonzini <pbonz...@redhat.com> > Signed-off-by: Brijesh Singh <brijesh.si...@amd.com> > --- > target/i386/sev.c | 11 +++++++++++ > 1 file changed, 11 insertions(+) > > diff --git a/target/i386/sev.c b/target/i386/sev.c > index 20b2d325d8..3e9d5c02fa 100644 > --- a/target/i386/sev.c > +++ b/target/i386/sev.c > @@ -131,6 +131,17 @@ sev_ram_block_added(RAMBlockNotifier *n, void *host, > size_t size) > { > int r; > struct kvm_enc_region range; > + ram_addr_t offset; > + MemoryRegion *mr; > + > + mr = memory_region_from_host(host, &offset); > + /* > + * The RAM device presents a memory region that should be treated > + * as IO region and should not be pinned. > + */ > + if (memory_region_is_ram_device(mr)) { > + return; > + } > > range.addr = (__u64)(unsigned long)host; > range.size = size; memory_region_from_host() can return NULL, which would give you a segfault at memory_region_is_ram_device(), so you might want to test mr on it's own first and decide which path that would take. Thanks, Alex
