When the handshake with daemon is complete, we should poll the channel since during the handshake, we will not be processing any messages. This is a potential bug if the host is waiting for a response from the guest. I would like to thank Dexuan for pointing this out.

Signed-off-by: K. Y. Srinivasan kys@microsoft.com Signed-off-by: Greg Kroah-Hartman gregkh@linuxfoundation.org Signed-off-by: Dexuan Cui decui@microsoft.com ---

This is cherry-picked from the mainline: 2d0c3b5 ("Drivers: hv: utils: Invoke the poll function after handshake")

I added my Signed-off-by as I identified and tested the patches. If this is unnecessary, please feel free to remove it.

drivers/hv/hv_kvp.c | 2 +- drivers/hv/hv_snapshot.c | 2 +- 2 files changed, 2 insertions(+), 2 deletions(-)

diff --git a/drivers/hv/hv_kvp.c b/drivers/hv/hv_kvp.c index ce4d3a9..b97ef3e 100644 --- a/drivers/hv/hv_kvp.c +++ b/drivers/hv/hv_kvp.c @@ -155,7 +155,7 @@ static int kvp_handle_handshake(struct hv_kvp_msg *msg) pr_debug("KVP: userspace daemon ver. %d registered\n", KVP_OP_REGISTER); kvp_register(dm_reg_value); - kvp_transaction.state = HVUTIL_READY; + hv_poll_channel(kvp_transaction.recv_channel, kvp_poll_wrapper);

return 0; } diff --git a/drivers/hv/hv_snapshot.c b/drivers/hv/hv_snapshot.c index faad79a..c5fb249 100644 --- a/drivers/hv/hv_snapshot.c +++ b/drivers/hv/hv_snapshot.c @@ -114,7 +114,7 @@ static int vss_handle_handshake(struct hv_vss_msg *vss_msg) default: return -EINVAL; } - vss_transaction.state = HVUTIL_READY; + hv_poll_channel(vss_transaction.recv_channel, vss_poll_wrapper); pr_debug("VSS: userspace daemon ver. %d registered\n", dm_reg_value); return 0; }