On 25/10/2023 15:50, David Woodhouse wrote:
From: David Woodhouse <d...@amazon.co.uk>When fire_watch_cb() found the response buffer empty, it would call deliver_watch() to generate the XS_WATCH_EVENT message in the response buffer and send an event channel notification to the guest… without actually *copying* the response buffer into the ring. So there was nothing for the guest to see. The pending response didn't actually get processed into the ring until the guest next triggered some activity from its side. Add the missing call to put_rsp(). It might have been slightly nicer to call xen_xenstore_event() here, which would *almost* have worked. Except for the fact that it calls xen_be_evtchn_pending() to check that it really does have an event pending (and clear the eventfd for next time). And under Xen it's defined that setting that fd to O_NONBLOCK isn't guaranteed to work, so the emu implementation follows suit. This fixes Xen device hot-unplug. Fixes: 0254c4d19df ("hw/xen: Add xenstore wire implementation and implementation stubs") Signed-off-by: David Woodhouse <d...@amazon.co.uk> --- hw/i386/kvm/xen_xenstore.c | 8 +++++--- 1 file changed, 5 insertions(+), 3 deletions(-)
Reviewed-by: Paul Durrant <p...@xen.org>
