From ddc9d357b991838c2d975e8d7e4e9db26f37a7ff Mon Sep 17 00:00:00 2001 From: Dexuan Cui Date: Sun, 19 Jan 2020 15:29:22 -0800 Subject: Drivers: hv: vmbus: Ignore CHANNELMSG_TL_CONNECT_RESULT(23) When a Linux hv_sock app tries to connect to a Service GUID on which no host app is listening, a recent host (RS3+) sends a CHANNELMSG_TL_CONNECT_RESULT (23) message to Linux and this triggers such a warning: unknown msgtype=23 WARNING: CPU: 2 PID: 0 at drivers/hv/vmbus_drv.c:1031 vmbus_on_msg_dpc Actually Linux can safely ignore the message because the Linux app's connect() will time out in 2 seconds: see VSOCK_DEFAULT_CONNECT_TIMEOUT and vsock_stream_connect(). We don't bother to make use of the message because: 1) it's only supported on recent hosts; 2) a non-trivial effort is required to use the message in Linux, but the benefit is small. So, let's not see the warning by silently ignoring the message. Signed-off-by: Dexuan Cui Reviewed-by: Michael Kelley Signed-off-by: Sasha Levin --- drivers/hv/channel_mgmt.c | 21 +++++++-------------- drivers/hv/vmbus_drv.c | 4 ++++ 2 files changed, 11 insertions(+), 14 deletions(-) (limited to 'drivers') diff --git a/drivers/hv/channel_mgmt.c b/drivers/hv/channel_mgmt.c index 8eb167540b4f..0370364169c4 100644 --- a/drivers/hv/channel_mgmt.c +++ b/drivers/hv/channel_mgmt.c @@ -1351,6 +1351,8 @@ channel_message_table[CHANNELMSG_COUNT] = { { CHANNELMSG_19, 0, NULL }, { CHANNELMSG_20, 0, NULL }, { CHANNELMSG_TL_CONNECT_REQUEST, 0, NULL }, + { CHANNELMSG_22, 0, NULL }, + { CHANNELMSG_TL_CONNECT_RESULT, 0, NULL }, }; /* @@ -1362,25 +1364,16 @@ void vmbus_onmessage(void *context) { struct hv_message *msg = context; struct vmbus_channel_message_header *hdr; - int size; hdr = (struct vmbus_channel_message_header *)msg->u.payload; - size = msg->header.payload_size; trace_vmbus_on_message(hdr); - if (hdr->msgtype >= CHANNELMSG_COUNT) { - pr_err("Received invalid channel message type %d size %d\n", - hdr->msgtype, size); - print_hex_dump_bytes("", DUMP_PREFIX_NONE, - (unsigned char *)msg->u.payload, size); - return; - } - - if (channel_message_table[hdr->msgtype].message_handler) - channel_message_table[hdr->msgtype].message_handler(hdr); - else - pr_err("Unhandled channel message type %d\n", hdr->msgtype); + /* + * vmbus_on_msg_dpc() makes sure the hdr->msgtype here can not go + * out of bound and the message_handler pointer can not be NULL. + */ + channel_message_table[hdr->msgtype].message_handler(hdr); } /* diff --git a/drivers/hv/vmbus_drv.c b/drivers/hv/vmbus_drv.c index 4ef5a66df680..029378c27421 100644 --- a/drivers/hv/vmbus_drv.c +++ b/drivers/hv/vmbus_drv.c @@ -1033,6 +1033,10 @@ void vmbus_on_msg_dpc(unsigned long data) } entry = &channel_message_table[hdr->msgtype]; + + if (!entry->message_handler) + goto msg_handled; + if (entry->handler_type == VMHT_BLOCKING) { ctx = kmalloc(sizeof(*ctx), GFP_ATOMIC); if (ctx == NULL) -- cgit v1.2.3-59-g8ed1b