On Tue, 2025-08-19 at 12:59 +0530, Harsh Prateek Bora wrote: > + Gautam, Glenn > > Hi Fabian, > > > On 8/19/25 08:25, Fabiano Rosas wrote: > > Fabian Vogt <fv...@suse.de> writes: > > > > +CC Peter > > > > > An obsolete wrapper function with a workaround was removed entirely, > > > without restoring the call it wrapped. > > > > > > Without this, the guest is stuck after savevm/loadvm. > > > > > > > I'd note that this only affects guests that have actually negotiated > > XICS, so guests using ic-mode=xive are safe. > > Since this affected only guests using XICS, would it be a better idea to > mention this explicitly in commit log as well (? > > > With this patch, backward migration to QEMU versions >= 9.2 is > > broken. Which I can only assume is ok, since the hard break (vmstate > > gets rejected) is better than weird post-migration hangs. > > > > If the PPC folks can spot a scenario where migration would provide > > reasonable results even without the emulated interrupt controller state > > being migrated, then we'll need a compat property for this. > >
I don't know much about the XICS controller, but migration without restoring the interrupt controller state seems pretty risky to me. I wouldn't recommend it. Glenn > > Also, a 9.2 guest cannot move to a more recent QEMU version without a > > reboot. If this is an important scenario, then the new QEMU needs to > > provide some compatibility knob. > > Gautam, Glenn - thoughts on above comments? > > Thanks for the patch. > > regards, > Harsh > > > Otherwise: > > > > Acked-by: Fabiano Rosas <faro...@suse.de> > > Cc: qemu-sta...@nongnu.org
