On Thu, Feb 09, 2023 at 01:54:42PM +0000, Daniel P. Berrangé wrote: > On Thu, Feb 09, 2023 at 01:45:33PM +0000, Richard W.M. Jones wrote: > > This machine type is more modern than the older 'pc' type and as most > > qemu development is now focused there we expect it will perform and > > behave better. In almost all respects this change should make no > > difference. > > The key differences with q35 that have caused problems for > apps in the past > > - CDROMs must use 'sata' bus not 'ide' > - PCI topology is completely different, so if you're > trying to associate between the host side view of > the config and the guest side view, your logic may > need adapting > - Hotplug of devices is limited to 1 device unless you > pre-create a bunch of pcie-root-port devices > > If you're already using 'virt' machine for aarch64 successfully > though, you should have already known about the last 2 points, > if they did indeed affect libguestfs. > > The first point could conceivably affect the way to detect > devices, depending on what approach is used, but could equally > be a non issue. > > I presume the libguestfs test suite would have complained if > there was any genuine problem with the change, since it is > pretty comphrensive.
I ran the full test suite and there were no complaints. In particular we do now do some complicated mapping between PCI and our internal device names[1] and at least the test of that didn't complain. I suspect we could see problems in guestfs-tools, especially things like virt-customize which are running things inside the appliance. For RHEL I have scheduled this change for early in the 9.3 cycle so there is plenty of time to test it. Rich. [1] https://github.com/libguestfs/libguestfs/blob/master/daemon/device-name-translation.c > > > > Fixes: https://bugzilla.redhat.com/show_bug.cgi?id=2168578 > > --- > > lib/guestfs-internal.h | 3 +++ > > 1 file changed, 3 insertions(+) > > > > diff --git a/lib/guestfs-internal.h b/lib/guestfs-internal.h > > index 07a2b9f617..4e9a103d78 100644 > > --- a/lib/guestfs-internal.h > > +++ b/lib/guestfs-internal.h > > @@ -128,6 +128,9 @@ cleanup_mutex_unlock (pthread_mutex_t **ptr) > > #define MAX_WINDOWS_EXPLORER_SIZE (4 * 1000 * 1000) > > > > /* Machine types. */ > > +#if defined(__x86_64__) > > +#define MACHINE_TYPE "q35" > > +#endif > > #ifdef __arm__ > > #define MACHINE_TYPE "virt" > > #endif > > -- > > 2.39.0 > > > > _______________________________________________ > > Libguestfs mailing list > > Libguestfs@redhat.com > > https://listman.redhat.com/mailman/listinfo/libguestfs > > > > With regards, > Daniel > -- > |: https://berrange.com -o- https://www.flickr.com/photos/dberrange :| > |: https://libvirt.org -o- https://fstop138.berrange.com :| > |: https://entangle-photo.org -o- https://www.instagram.com/dberrange :| -- Richard Jones, Virtualization Group, Red Hat http://people.redhat.com/~rjones Read my programming and virtualization blog: http://rwmj.wordpress.com virt-top is 'top' for virtual machines. Tiny program with many powerful monitoring features, net stats, disk stats, logging, etc. http://people.redhat.com/~rjones/virt-top _______________________________________________ Libguestfs mailing list Libguestfs@redhat.com https://listman.redhat.com/mailman/listinfo/libguestfs
