Patch "uio_hv_generic: check that host supports monitor page" has been added to the 4.14-stable tree

This is a note to let you know that I've just added the patch titled

uio_hv_generic: check that host supports monitor page

to the 4.14-stable tree which can be found at:
http://www.kernel.org/git/?p=linux/kernel/git/stable/stable-queue.git;a=summary

The filename of the patch is:
uio_hv_generic-check-that-host-supports-monitor-page.patch
and it can be found in the queue-4.14 subdirectory.

If you, or anyone else, feels it should not be added to the stable tree, please let <[email protected]> know about it.

From: Stephen Hemminger <[email protected]>
Date: Tue, 9 Jan 2018 12:57:31 -0800
Subject: uio_hv_generic: check that host supports monitor page

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.

---
 drivers/uio/uio_hv_generic.c |    7 +++++++
 1 file changed, 7 insertions(+)

@@ -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);
 

Patches currently in stable-queue which might be from [email protected] are

queue-4.14/uio_hv_generic-check-that-host-supports-monitor-page.patch