Re: [PATCH v2 4/4] misc: fastrpc: Skip reference for DMA handles

Re: [PATCH v2 4/4] misc: fastrpc: Skip reference for DMA handles

[kernel test robot]

Hi Ling,

kernel test robot noticed the following build warnings:

[auto build test WARNING on char-misc/char-misc-testing]
[also build test WARNING on char-misc/char-misc-next char-misc/char-misc-linus linus/master v6.16 next-20250806]
[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#_base_tree_information]

url:    https://github.com/intel-lab-lkp/linux/commits/Ling-Xu/misc-fastrpc-Save-actual-DMA-size-in-fastrpc_map-structure/20250806-200133
base:   char-misc/char-misc-testing
patch link:    https://lore.kernel.org/r/20250806115114.688814-5-quic_lxu5%40quicinc.com
patch subject: [PATCH v2 4/4] misc: fastrpc: Skip reference for DMA handles
config: hexagon-randconfig-002-20250807 (https://download.01.org/0day-ci/archive/20250807/202508070731.S30957lV-lkp@intel.com/config)
compiler: clang version 22.0.0git (https://github.com/llvm/llvm-project 7b8dea265e72c3037b6b1e54d5ab51b7e14f328b)
reproduce (this is a W=1 build): (https://download.01.org/0day-ci/archive/20250807/202508070731.S30957lV-lkp@intel.com/reproduce)

If you fix the issue in a separate patch/commit (i.e. not just a new version of
the same patch/commit), kindly add following tags
| Reported-by: kernel test robot <lkp@intel.com>
| Closes: https://lore.kernel.org/oe-kbuild-all/202508070731.S30957lV-lkp@intel.com/

All warnings (new ones prefixed by >>):

>> drivers/misc/fastrpc.c:368:30: warning: unused variable 'sess' [-Wunused-variable]
     368 |         struct fastrpc_session_ctx *sess = fl->sctx;
         |                                     ^~~~
   1 warning generated.


vim +/sess +368 drivers/misc/fastrpc.c

c68cfb718c8f97 Srinivas Kandagatla      2019-02-08  363  
8f6c1d8c4f0cc3 Vamsi Krishna Gattupalli 2022-02-14  364  
8f6c1d8c4f0cc3 Vamsi Krishna Gattupalli 2022-02-14  365  static int fastrpc_map_lookup(struct fastrpc_user *fl, int fd,
1922c68c56c660 Ling Xu                  2025-08-06  366  			    struct fastrpc_map **ppmap)
c68cfb718c8f97 Srinivas Kandagatla      2019-02-08  367  {
9446fa1683a7e3 Abel Vesa                2022-11-24 @368  	struct fastrpc_session_ctx *sess = fl->sctx;
c68cfb718c8f97 Srinivas Kandagatla      2019-02-08  369  	struct fastrpc_map *map = NULL;
d259063578ed76 Ling Xu                  2025-08-06  370  	struct dma_buf *buf;
9446fa1683a7e3 Abel Vesa                2022-11-24  371  	int ret = -ENOENT;
c68cfb718c8f97 Srinivas Kandagatla      2019-02-08  372  
d259063578ed76 Ling Xu                  2025-08-06  373  	buf = dma_buf_get(fd);
d259063578ed76 Ling Xu                  2025-08-06  374  	if (IS_ERR(buf))
d259063578ed76 Ling Xu                  2025-08-06  375  		return PTR_ERR(buf);
d259063578ed76 Ling Xu                  2025-08-06  376  
9446fa1683a7e3 Abel Vesa                2022-11-24  377  	spin_lock(&fl->lock);
c68cfb718c8f97 Srinivas Kandagatla      2019-02-08  378  	list_for_each_entry(map, &fl->maps, node) {
d259063578ed76 Ling Xu                  2025-08-06  379  		if (map->fd != fd || map->buf != buf)
9446fa1683a7e3 Abel Vesa                2022-11-24  380  			continue;
9446fa1683a7e3 Abel Vesa                2022-11-24  381  
9446fa1683a7e3 Abel Vesa                2022-11-24  382  		*ppmap = map;
9446fa1683a7e3 Abel Vesa                2022-11-24  383  		ret = 0;
9446fa1683a7e3 Abel Vesa                2022-11-24  384  		break;
c68cfb718c8f97 Srinivas Kandagatla      2019-02-08  385  	}
9446fa1683a7e3 Abel Vesa                2022-11-24  386  	spin_unlock(&fl->lock);
8f6c1d8c4f0cc3 Vamsi Krishna Gattupalli 2022-02-14  387  
8f6c1d8c4f0cc3 Vamsi Krishna Gattupalli 2022-02-14  388  	return ret;
8f6c1d8c4f0cc3 Vamsi Krishna Gattupalli 2022-02-14  389  }
8f6c1d8c4f0cc3 Vamsi Krishna Gattupalli 2022-02-14  390  

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