Daniel P. Berrange writes ("[Xen-devel] RFC: Making QEMU honour 'readonly' flag
for disks"):
The Xen disk configuration syntax allows a block device to be marked as
readonly, exclusive writable or shared writeable. The xen hotplug scripts
will clash for clashing configs between domains, but it is upto the
backend drivers to actually enforce the readonly flag on I/O operations.
The paravirt backend disk driver does this fine, but QEMU's emulated
backend driver does not.
I still think this is a fix we should have but your patch is very
intrusive. Is there some reason why you didn't just invent
BDRV_O_RDONLY_NO__ACTUALLY__READONLY ? A new parameter to bdrv_new
seems quite wrong.
(It's a shame that the existing BDRV_O_RDONLY does something strange
and probably wrong, but we probably don't want to fix that in our
branch.)
Would you be willing to prepare a revised patch along those lines ?
If you don't want to deal with upstream I can put your change in the
pile with the others ...
Ian.
7 messages in com.xensource.lists.xen-develRe: [Xen-devel] RFC: Making QEMU hono...