[PATCH 4.4 45/48] Drivers: hv: utils: Invoke the poll function after handshake

From: Greg Kroah-Hartman
Date: Thu Oct 18 2018 - 14:06:53 EST


4.4-stable review patch. If anyone has any objections, please let me know.

------------------

From: K. Y. Srinivasan <kys@xxxxxxxxxxxxx>

commit 2d0c3b5ad739697a68dc8a444f5b9f4817cf8f8f upstream.

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@xxxxxxxxxxxxx>
Signed-off-by: Dexuan Cui <decui@xxxxxxxxxxxxx>
Signed-off-by: Greg Kroah-Hartman <gregkh@xxxxxxxxxxxxxxxxxxx>
---
drivers/hv/hv_kvp.c | 2 +-
drivers/hv/hv_snapshot.c | 2 +-
2 files changed, 2 insertions(+), 2 deletions(-)

--- a/drivers/hv/hv_kvp.c
+++ b/drivers/hv/hv_kvp.c
@@ -155,7 +155,7 @@ static int kvp_handle_handshake(struct h
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;
}
--- a/drivers/hv/hv_snapshot.c
+++ b/drivers/hv/hv_snapshot.c
@@ -114,7 +114,7 @@ static int vss_handle_handshake(struct h
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;
}