The spapr-vty device implements the PAPR defined virtual console,
which is also implemented by IBM's proprietary PowerVM hypervisor.
PowerVM's implementation has a bug where it inserts an extra \0 after
every \r going to the guest. Because of that Linux's guest side
driver has a workaround which strips \0 characters that appear
immediately after a \r.
That means that when running under qemu, sending a binary stream from
host to guest via spapr-vty which happens to include a \r\0 sequence
will get corrupted by that workaround.
To deal with that, this patch duplicates PowerVM's bug, inserting an
extra \0 after each \r. Ugly, but the best option available.
Signed-off-by: David Gibson <david@gibson.dropbear.id.au>
Reviewed-by: Thomas Huth <thuth@redhat.com>
Reviewed-by: Greg Kurz <groug@kaod.org>
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