From: Stephen Hemminger <[email protected]> [ Upstream commit 06028d15177a1b406b7b075ea47c6a352732f23a ]
In order for userspace application to signal host, it needs the host to support the monitor page property. Check for the flag and fail if this is not supported. Signed-off-by: Stephen Hemminger <[email protected]> Signed-off-by: Greg Kroah-Hartman <[email protected]> Signed-off-by: Sasha Levin <[email protected]> --- drivers/uio/uio_hv_generic.c | 7 +++++++ 1 file changed, 7 insertions(+) diff --git a/drivers/uio/uio_hv_generic.c b/drivers/uio/uio_hv_generic.c index 48d5327d38d4..fe5cdda80b2c 100644 --- a/drivers/uio/uio_hv_generic.c +++ b/drivers/uio/uio_hv_generic.c @@ -124,6 +124,13 @@ hv_uio_probe(struct hv_device *dev, if (ret) goto fail; + /* Communicating with host has to be via shared memory not hypercall */ + if (!dev->channel->offermsg.monitor_allocated) { + dev_err(&dev->device, "vmbus channel requires hypercall\n"); + ret = -ENOTSUPP; + goto fail_close; + } + dev->channel->inbound.ring_buffer->interrupt_mask = 1; set_channel_read_mode(dev->channel, HV_CALL_DIRECT); -- 2.14.1
