4.14-stable review patch. If anyone has any objections, please let me know.
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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);