Re: [PATCH 3/5] x86/vmsi: use the newly introduced EOI callbacks

[Jan Beulich <jbeulich@xxxxxxxx>]

On 12.08.2020 14:47, Roger Pau Monne wrote:
> Remove the unconditional call to hvm_dpci_msi_eoi in vlapic_handle_EOI
> and instead use the newly introduced EOI callback mechanism in order
> to register a callback for MSI vectors injected from passed through
> devices.

In patch 2 you merely invoke the callback when the EOI arrived,
but you don't clear the callback (unless I've missed something).
Here you register the callback once per triggering of the IRQ,
without clearing it from the callback itself either. Why is it
correct / safe to keep the callback registered? What about
conflicting callbacks for shared vectors?

Jan