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%3Ba=su...

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 stable@vger.kernel.org know about it.

From foo@baz Mon Apr 9 13:58:16 CEST 2018

From: Stephen Hemminger stephen@networkplumber.org Date: Tue, 9 Jan 2018 12:57:31 -0800 Subject: uio_hv_generic: check that host supports monitor page

From: Stephen Hemminger stephen@networkplumber.org

[ 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 sthemmin@microsoft.com Signed-off-by: Greg Kroah-Hartman gregkh@linuxfoundation.org Signed-off-by: Sasha Levin alexander.levin@microsoft.com Signed-off-by: Greg Kroah-Hartman gregkh@linuxfoundation.org --- drivers/uio/uio_hv_generic.c | 7 +++++++ 1 file changed, 7 insertions(+)

--- 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);

Patches currently in stable-queue which might be from stephen@networkplumber.org are

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