From: kys@exchange.microsoft.com
To: gregkh@linuxfoundation.org, linux-kernel@vger.kernel.org,
        devel@linuxdriverproject.org, olaf@aepfle.de, apw@canonical.com,
        vkuznets@redhat.com, jasowang@redhat.com,
        leann.ogasawara@canonical.com, sthemmin@microsoft.com
Cc: Alex Ng <alexng@messages.microsoft.com>,
        Alex Ng <alexng@microsoft.com>, "K. Y. Srinivasan" <kys@microsoft.com>
Subject: [PATCH V3 04/14] Drivers: hv: balloon: Disable hot add when CONFIG_MEMORY_HOTPLUG is not set
Date: Sun,  6 Nov 2016 13:14:08 -0800
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From: Alex Ng <alexng@messages.microsoft.com>

If the guest does not support memory hotplugging, it should respond to
the host with zero pages added and successful result code. This signals
to the host that hotplugging is not supported and the host will avoid
sending future hot-add requests.

Signed-off-by: Alex Ng <alexng@microsoft.com>
Signed-off-by: K. Y. Srinivasan <kys@microsoft.com>
---
 drivers/hv/hv_balloon.c |    4 ++++
 1 files changed, 4 insertions(+), 0 deletions(-)

diff --git a/drivers/hv/hv_balloon.c b/drivers/hv/hv_balloon.c
index fdf8da9..8f932aa 100644
--- a/drivers/hv/hv_balloon.c
+++ b/drivers/hv/hv_balloon.c
@@ -1501,7 +1501,11 @@ static int balloon_probe(struct hv_device *dev,
 	struct dm_version_request version_req;
 	struct dm_capabilities cap_msg;
 
+#ifdef CONFIG_MEMORY_HOTPLUG
 	do_hot_add = hot_add;
+#else
+	do_hot_add = false;
+#endif
 
 	/*
 	 * First allocate a send buffer.
-- 
1.7.4.1