Commit d56ec1e9 authored by Michael S. Tsirkin's avatar Michael S. Tsirkin
Browse files

vhost: skip ROM sections 



vhost does not support RO protections on memory at the moment - adding
ROMs would mean that e.g. a buggy guest might change them in-memory - a
condition from which guest reset does not recover. Not nice.

We also definitely don't want to try logging writes into ROMs -
in particular guests set very high addresses for ROM BARs
so logging these writes would waste a lot of memory.

Maybe ROMs could be supported with the iotlb variant -
not sure, but there seems to be no good reason for virtio
to try to do DMA from ROM. So let's just skip ROM memory.

Suggested-by: default avatarLaurent Vivier <lvivier@redhat.com>
Signed-off-by: default avatarMichael S. Tsirkin <mst@redhat.com>
Reviewed-by: default avatarLaurent Vivier <lvivier@redhat.com>
Tested-by: default avatarLaurent Vivier <lvivier@redhat.com>
parent c25d97c4

hw/virtio/vhost.c

+2 −1
Original line number Diff line number Diff line
@@ -612,7 +612,8 @@ static void vhost_set_memory(MemoryListener *listener, 


static bool vhost_section(MemoryRegionSection *section)

{

    return memory_region_is_ram(section->mr);

    return memory_region_is_ram(section->mr) &&

        !memory_region_is_rom(section->mr);

}



static void vhost_begin(MemoryListener *listener)