Jordan Justen <jljus...@gmail.com> writes: > On Tue, Nov 26, 2013 at 5:32 AM, Laszlo Ersek <ler...@redhat.com> wrote: >> On 11/26/13 13:36, Markus Armbruster wrote: >> >>> Your stated purpose for multiple -pflash: >>> >>> This accommodates the following use case: suppose that OVMF is split in >>> two parts, a writeable host file for non-volatile variable storage, and >>> a >>> read-only part for bootstrap and decompressible executable code. >>> >>> Such a split between writable part and read-only part makes sense to me. >>> How is it done in physical hardware? Single device with configurable >>> write-protect, or two separate devices? >> >> (Jordan could help more.) >> >> Likely one device that's fully writeable. > > Most parts will have a dedicated read-only line. > > Many devices have 'block-locking' that will make some subset of blocks > read-only until a reset. > > In addition to this, many chipsets will allow flash writes to be > protected by triggering SMM when a flash write occurs. > > Using multiple chips are less common due to cost, but this is not a > factor for QEMU. :)
Should we stick to what real hardware does? Single device, perhaps with block locking.
