Re: [PATCH v12 1/2] drivers/coresight: Add UltraSoc System Memory Buffer driver

[Suzuki K Poulose <suzuki.poulose@arm.com>]

On 11/11/2022 22:06, kernel test robot wrote:
> Hi Junhao,
> 
> I love your patch! Perhaps something to improve:
> 
> [auto build test WARNING on soc/for-next]
> [also build test WARNING on linus/master v6.1-rc4 next-20221111]
> [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/Junhao-He/Add-support-for-UltraSoc-System-Memory-Buffer/20221109-215158
> base:   https://git.kernel.org/pub/scm/linux/kernel/git/soc/soc.git for-next
> patch link:    https://lore.kernel.org/r/20221109135008.9485-2-hejunhao3%40huawei.com
> patch subject: [PATCH v12 1/2] drivers/coresight: Add UltraSoc System Memory Buffer driver
> config: arm64-randconfig-s033-20221111
> compiler: aarch64-linux-gcc (GCC) 12.1.0
> reproduce:
>          wget https://raw.githubusercontent.com/intel/lkp-tests/master/sbin/make.cross -O ~/bin/make.cross
>          chmod +x ~/bin/make.cross
>          # apt-get install sparse
>          # sparse version: v0.6.4-39-gce1a6720-dirty
>          # https://github.com/intel-lab-lkp/linux/commit/49ede03fd874b65deca5382ea84c3377188136da
>          git remote add linux-review https://github.com/intel-lab-lkp/linux
>          git fetch --no-tags linux-review Junhao-He/Add-support-for-UltraSoc-System-Memory-Buffer/20221109-215158
>          git checkout 49ede03fd874b65deca5382ea84c3377188136da
>          # save the config file
>          mkdir build_dir && cp config build_dir/.config
>          COMPILER_INSTALL_PATH=$HOME/0day COMPILER=gcc-12.1.0 make.cross C=1 CF='-fdiagnostic-prefix -D__CHECK_ENDIAN__' O=build_dir ARCH=arm64 SHELL=/bin/bash drivers/hwtracing/coresight/
> 
> If you fix the issue, kindly add following tag where applicable
> | Reported-by: kernel test robot <lkp@intel.com>
> 
> sparse warnings: (new ones prefixed by >>)
>>> drivers/hwtracing/coresight/ultrasoc-smb.c:113:33: sparse: sparse: cast removes address space '__iomem' of expression
>>> drivers/hwtracing/coresight/ultrasoc-smb.c:354:17: sparse: sparse: incorrect type in argument 1 (different address spaces) @@     expected void const * @@     got void [noderef] __iomem * @@
>     drivers/hwtracing/coresight/ultrasoc-smb.c:354:17: sparse:     expected void const *
>     drivers/hwtracing/coresight/ultrasoc-smb.c:354:17: sparse:     got void [noderef] __iomem *
>>> drivers/hwtracing/coresight/ultrasoc-smb.c:354:17: sparse: sparse: incorrect type in argument 1 (different address spaces) @@     expected void const * @@     got void [noderef] __iomem * @@
>     drivers/hwtracing/coresight/ultrasoc-smb.c:354:17: sparse:     expected void const *
>     drivers/hwtracing/coresight/ultrasoc-smb.c:354:17: sparse:     got void [noderef] __iomem *
>     drivers/hwtracing/coresight/ultrasoc-smb.c:354:17: sparse: sparse: incorrect type in argument 2 (different address spaces) @@     expected void const * @@     got void [noderef] __iomem * @@
>     drivers/hwtracing/coresight/ultrasoc-smb.c:354:17: sparse:     expected void const *
>     drivers/hwtracing/coresight/ultrasoc-smb.c:354:17: sparse:     got void [noderef] __iomem *
>>> drivers/hwtracing/coresight/ultrasoc-smb.c:463:14: sparse: sparse: incorrect type in assignment (different address spaces) @@     expected void [noderef] __iomem *base @@     got void * @@
>     drivers/hwtracing/coresight/ultrasoc-smb.c:463:14: sparse:     expected void [noderef] __iomem *base
>     drivers/hwtracing/coresight/ultrasoc-smb.c:463:14: sparse:     got void *
> 
> vim +/__iomem +113 drivers/hwtracing/coresight/ultrasoc-smb.c
> 
>      89	
>      90	static ssize_t smb_read(struct file *file, char __user *data, size_t len,
>      91				loff_t *ppos)
>      92	{
>      93		struct smb_drv_data *drvdata = container_of(file->private_data,
>      94						struct smb_drv_data, miscdev);
>      95		struct smb_data_buffer *sdb = &drvdata->sdb;
>      96		struct device *dev = &drvdata->csdev->dev;
>      97		ssize_t to_copy = 0;
>      98	
>      99		mutex_lock(&drvdata->mutex);
>     100	
>     101		if (!sdb->data_size) {
>     102			smb_update_data_size(drvdata);
>     103			if (!sdb->data_size)
>     104				goto out;
>     105		}
>     106	
>     107		to_copy = min(sdb->data_size, len);
>     108	
>     109		/* Copy parts of trace data when read pointer wrap around SMB buffer */
>     110		if (sdb->rd_offset + to_copy > sdb->buf_size)
>     111			to_copy = sdb->buf_size - sdb->rd_offset;
>     112	
>   > 113		if (copy_to_user(data, (void *)sdb->buf_base + sdb->rd_offset,
>     114				 to_copy)) {
>     115			dev_dbg(dev, "Failed to copy data to user\n");
>     116			to_copy = -EFAULT;
>     117			goto out;
>     118		}
>     119	

Please could we replace this with copy_to_user_fromio() ?

Suzuki