From: Roman Kisel <[email protected]> Sent: Monday, July 14, 2025 3:16 PM > > When the confidential VMBus is available, the guest should post > messages to the paravisor. > > Update hv_post_message() to post messages to the paravisor rather than > through GHCB or TD calls. > > Signed-off-by: Roman Kisel <[email protected]>
Reviewed-by: Michael Kelley <[email protected]> > --- > drivers/hv/hv.c | 11 ++++++++++- > 1 file changed, 10 insertions(+), 1 deletion(-) > > diff --git a/drivers/hv/hv.c b/drivers/hv/hv.c > index e9ee0177d765..816f8a14ff63 100644 > --- a/drivers/hv/hv.c > +++ b/drivers/hv/hv.c > @@ -74,7 +74,11 @@ int hv_post_message(union hv_connection_id connection_id, > aligned_msg->payload_size = payload_size; > memcpy((void *)aligned_msg->payload, payload, payload_size); > > - if (ms_hyperv.paravisor_present) { > + if (ms_hyperv.paravisor_present && !vmbus_is_confidential()) { > + /* > + * If the VMBus isn't confidential, use the CoCo-specific > + * mechanism to communicate with the hypervisor. > + */ > if (hv_isolation_type_tdx()) > status = hv_tdx_hypercall(HVCALL_POST_MESSAGE, > virt_to_phys(aligned_msg), 0); > @@ -85,6 +89,11 @@ int hv_post_message(union hv_connection_id connection_id, > else > status = HV_STATUS_INVALID_PARAMETER; > } else { > + /* > + * If there is no paravisor, this will go to the hypervisor. > + * In the Confidential VMBus case, there is the paravisor > + * to which this will trap. > + */ > status = hv_do_hypercall(HVCALL_POST_MESSAGE, > aligned_msg, NULL); > } > -- > 2.43.0
