On 14/11/23 16:13, David Woodhouse wrote:
On 14 November 2023 09:38:02 GMT-05:00, "Philippe Mathieu-Daudé" <philmd@xxxxxxxxxx> wrote:
Similarly to the restriction in hw/pci/msix.c (see commit
e1e4bf2252 "msix: fix msix_vector_masked"), restrict the
xen_is_pirq_msi() call in msi_is_masked() to Xen.
Signed-off-by: Philippe Mathieu-Daudé <philmd@xxxxxxxxxx>
Hm, we do also support the Xen abomination of snooping on MSI table writes to see if they're targeted at a Xen PIRQ, then actually unmasking the MSI from QEMU when the guest binds the corresponding event channel to that PIRQ.
I think this is going to break in CI as kvm_xen_guest.py does deliberately exercise that use case, doesn't it?
Hmmm I see what you mean.
So you mentioned these checks:
- host Xen accel
- Xen accel emulated to guest via KVM host accel
Maybe we need here:
- guest expected to run Xen
Being (
Xen accel emulated to guest via KVM host accel
OR
host Xen accel
)
If so, possibly few places incorrectly check 'xen_enabled()'
instead of this 'xen_guest()'.
"Xen on KVM" is a tricky case...
I deliberately *didn't* switch to testing the Xen PV net device, with a comment that testing MSI and irqchip permutations was far more entertaining. So I hope it should catch this?
¯\_(ツ)_/¯
