4080a13c11
When an I/O port is more than 1 byte long, ioport.c is currently creating "short" regions, for example 0x1ce-0x1ce for the 16-bit Bochs index port. When I/O ports are memory mapped, and thus accessed via a subpage_ops memory region, subpage_accepts gets confused because it finds a hole at 0x1cf and rejects the access. In order to fix this, modify registration of the region to cover the whole size of the I/O port. Attempts to access an invalid port will be blocked by find_portio returning NULL. This only affects the VBE DISPI regions. For all other cases, the MemoryRegionPortio entries for 2- or 4-byte accesses overlap an entry for 1-byte accesses, thus the size of the memory region is not affected. Reported-by: Zoltan Balaton <balaton@eik.bme.hu> Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
Read the documentation in qemu-doc.html or on http://wiki.qemu-project.org - QEMU team