On Thu, Jul 02, 2020 at 04:10:57PM +0100, Andrew Cooper wrote: [...] > > > +#include <stdlib.h> > > +#include <stdio.h> > > +#include <sys/mman.h> > > +#include <signal.h> > > + > > +#include <xenctrl.h> > > +#include <xen/xen.h> > > +#include <xenforeignmemory.h> > > + > > +#define BUF_SIZE (16384 * XC_PAGE_SIZE) > > This hardcodes the size of the buffer which is configurable per VM. > Mapping the buffer fails when it is smaller than this. > > It appears there is still outstanding bug from the acquire_resource work > which never got fixed. The guest_handle_is_null(xmar.frame_list) path > in Xen is supposed to report the size of the resource, not the size of > Xen's local buffer, so userspace can ask "how large is this resource". > > I'll try and find some time to fix this and arrange for backports, but > the current behaviour is nonsense, and problematic for new users.
I can't quite figure out if this is a blocking comment of this tool to be accepted. Can you clarify? Wei. > > ~Andrew