Re: [PATCH 2/3] virtio: cache indirect desc for packed

Hi Xuan,

Thank you for the patch! Perhaps something to improve:

[auto build test WARNING on horms-ipvs/master]
[also build test WARNING on linus/master v5.15-rc7]
[cannot apply to mst-vhost/linux-next next-20211027]
[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/Xuan-Zhuo/virtio-support-cache-indirect-desc/20211027-142025
base:   https://git.kernel.org/pub/scm/linux/kernel/git/horms/ipvs.git master
config: i386-randconfig-s002-20211027 (attached as .config)
compiler: gcc-9 (Debian 9.3.0-22) 9.3.0
reproduce:
        # apt-get install sparse
        # sparse version: v0.6.4-dirty
        # https://github.com/0day-ci/linux/commit/bb65ceda850ed4592d8a940e01926d5e3d33ae92
        git remote add linux-review https://github.com/0day-ci/linux
        git fetch --no-tags linux-review Xuan-Zhuo/virtio-support-cache-indirect-desc/20211027-142025
        git checkout bb65ceda850ed4592d8a940e01926d5e3d33ae92
        # save the attached .config to linux build tree
        make W=1 C=1 CF='-fdiagnostic-prefix -D__CHECK_ENDIAN__' O=build_dir ARCH=i386 SHELL=/bin/bash drivers/virtio/

If you fix the issue, kindly add following tag as appropriate
Reported-by: kernel test robot <redacted>


sparse warnings: (new ones prefixed by >>)
   drivers/virtio/virtio_ring.c:438:26: sparse: sparse: cast from restricted __virtio64
   drivers/virtio/virtio_ring.c:447:28: sparse: sparse: incorrect type in assignment (different base types) @@     expected restricted __virtio64 [usertype] addr @@     got unsigned long long [usertype] @@
   drivers/virtio/virtio_ring.c:447:28: sparse:     expected restricted __virtio64 [usertype] addr
   drivers/virtio/virtio_ring.c:447:28: sparse:     got unsigned long long [usertype]
   drivers/virtio/virtio_ring.c:464:49: sparse: sparse: cast from restricted __virtio64

quoted

drivers/virtio/virtio_ring.c:1083:26: sparse: sparse: cast from restricted __le64
drivers/virtio/virtio_ring.c:1092:28: sparse: sparse: incorrect type in assignment (different base types) @@     expected restricted __le64 [usertype] addr @@     got unsigned long long [usertype] @@

   drivers/virtio/virtio_ring.c:1092:28: sparse:     expected restricted __le64 [usertype] addr
   drivers/virtio/virtio_ring.c:1092:28: sparse:     got unsigned long long [usertype]
   drivers/virtio/virtio_ring.c:1109:49: sparse: sparse: cast from restricted __le64

vim +1083 drivers/virtio/virtio_ring.c

  1076	
  1077	static void desc_cache_chain_free_packed(void *chain)
  1078	{
  1079		struct vring_packed_desc *desc;
  1080	
  1081		while (chain) {
  1082			desc = chain;

1083			chain = (void *)desc->addr;

  1084			kfree(desc);
  1085		}
  1086	}
  1087	
  1088	static void desc_cache_put_packed(struct vring_virtqueue *vq,
  1089					  struct vring_packed_desc *desc, int n)
  1090	{
  1091		if (vq->use_desc_cache && n <= VIRT_QUEUE_CACHE_DESC_NUM) {

1092			desc->addr = (u64)vq->desc_cache_chain;

  1093			vq->desc_cache_chain = desc;
  1094		} else {
  1095			kfree(desc);
  1096		}
  1097	}
  1098	

---
0-DAY CI Kernel Test Service, Intel Corporation
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