Received-SPF: pass (google.com: domain of linux-kernel-owner@vger.kernel.org designates 23.128.96.18 as permitted sender) client-ip=23.128.96.18;
From:   Xiongfeng Wang <wangxiongfeng2@huawei.com>
To:     <airlied@linux.ie>, <daniel@ffwll.ch>
CC:     <zhenyuw@linux.intel.com>, <intel-gvt-dev@lists.freedesktop.org>,
        <intel-gfx@lists.freedesktop.org>,
        <dri-devel@lists.freedesktop.org>, <linux-kernel@vger.kernel.org>,
        <wangxiongfeng2@huawei.com>, <chenzhou10@huawei.com>
Subject: [PATCH] drm/i915/gvt: return error when failing to take the module reference
Date:   Thu, 12 Nov 2020 21:22:32 +0800
Message-ID: <1605187352-51761-1-git-send-email-wangxiongfeng2@huawei.com>
MIME-Version: 1.0
Content-Type: text/plain
Precedence: bulk

When we fail to take the module reference, we go to the 'undo*' branch and
return. But the returned variable 'ret' has been set as zero by the
above code. Change 'ret' to '-ENODEV' in this situation.

Fixes: 9bdb073464d6 ("drm/i915/gvt: Change KVMGT as self load module")
Reported-by: Hulk Robot <hulkci@huawei.com>
Signed-off-by: Xiongfeng Wang <wangxiongfeng2@huawei.com>
---
 drivers/gpu/drm/i915/gvt/kvmgt.c | 4 +++-
 1 file changed, 3 insertions(+), 1 deletion(-)

diff --git a/drivers/gpu/drm/i915/gvt/kvmgt.c b/drivers/gpu/drm/i915/gvt/kvmgt.c
index ad8a9df..778eb8c 100644
--- a/drivers/gpu/drm/i915/gvt/kvmgt.c
+++ b/drivers/gpu/drm/i915/gvt/kvmgt.c
@@ -829,8 +829,10 @@ static int intel_vgpu_open(struct mdev_device *mdev)
 	/* Take a module reference as mdev core doesn't take
 	 * a reference for vendor driver.
 	 */
-	if (!try_module_get(THIS_MODULE))
+	if (!try_module_get(THIS_MODULE)) {
+		ret = -ENODEV;
 		goto undo_group;
+	}
 
 	ret = kvmgt_guest_init(mdev);
 	if (ret)
-- 
1.7.12.4