Hi Zhu,

Thank you for the patch! Perhaps something to improve:

[auto build test WARNING on vhost/linux-next]
[also build test WARNING on kvm/linux-next linus/master v5.8-rc5 next-20200716]
[If your patch is applied to the wrong git tree, kindly drop us a note.
And when submitting patch, we suggest to use '--base' as documented in
https://git-scm.com/docs/git-format-patch]

url:    https://github.com/0day-ci/linux/commits/Zhu-Lingshan/IRQ-offloading-for-vDPA/20200716-192910
base:   https://git.kernel.org/pub/scm/linux/kernel/git/mst/vhost.git linux-next
config: openrisc-randconfig-r016-20200717 (attached as .config)
compiler: or1k-linux-gcc (GCC) 9.3.0
reproduce (this is a W=1 build):
        wget https://raw.githubusercontent.com/intel/lkp-tests/master/sbin/make.cross -O ~/bin/make.cross
        chmod +x ~/bin/make.cross
        # save the attached .config to linux build tree
        COMPILER_INSTALL_PATH=$HOME/0day COMPILER=gcc-9.3.0 make.cross ARCH=openrisc 

If you fix the issue, kindly add following tag as appropriate
Reported-by: kernel test robot <lkp@intel.com>

All warnings (new ones prefixed by >>):

   drivers/vhost/vdpa.c: In function 'vhost_vdpa_setup_vq_irq':
>> drivers/vhost/vdpa.c:122:6: warning: variable 'ret' set but not used [-Wunused-but-set-variable]
     122 |  int ret;
         |      ^~~

vim +/ret +122 drivers/vhost/vdpa.c

   117	
   118	static void vhost_vdpa_setup_vq_irq(struct vdpa_device *dev, int qid, int irq)
   119	{
   120		struct vhost_vdpa *v = vdpa_get_drvdata(dev);
   121		struct vhost_virtqueue *vq = &v->vqs[qid];
 > 122		int ret;
   123	
   124		spin_lock(&vq->call_ctx.ctx_lock);
   125		if (!vq->call_ctx.ctx) {
   126			spin_unlock(&vq->call_ctx.ctx_lock);
   127			return;
   128		}
   129	
   130		vq->call_ctx.producer.token = vq->call_ctx.ctx;
   131		vq->call_ctx.producer.irq = irq;
   132		ret = irq_bypass_register_producer(&vq->call_ctx.producer);
   133		spin_unlock(&vq->call_ctx.ctx_lock);
   134	}
   135	

---
0-DAY CI Kernel Test Service, Intel Corporation
https://lists.01.org/hyperkitty/list/kbuild-all@lists.01.org