Re: [PATCH v1 12/15] powerpc/uaccess: Refactor get/put_user() and __get/put_user()

Christophe Leroy
2021-03-08T12:15:58Z

+Evgeniy for W1 Dallas
+Alex & Christian for RADEON

Le 07/03/2021 à 11:23, kernel test robot a écrit :
> Hi Christophe,
>
> I love your patch! Perhaps something to improve:
>
> [auto build test WARNING on powerpc/next]
> [also build test WARNING on v5.12-rc2 next-20210305]
> [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/Christophe-Leroy/powerpc-Cleanup-of-uaccess-h/20210226-015715
> base: https://git.kernel.org/pub/scm/linux/kernel/git/powerpc/linux.git next
> config: powerpc-randconfig-s031-20210307 (attached as .config)
> compiler: powerpc-linux-gcc (GCC) 9.3.0
> 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: v0.6.3-245-gacc5c298-dirty
> # https://github.com/0day-ci/linux/commit/449bdbf978936e67e4919be8be0eec3e490a65e2
> git remote add linux-review https://github.com/0day-ci/linux
> git fetch --no-tags linux-review Christophe-Leroy/powerpc-Cleanup-of-uaccess-h/20210226-015715
> git checkout 449bdbf978936e67e4919be8be0eec3e490a65e2
> # save the attached .config to linux build tree
> COMPILER_INSTALL_PATH=$HOME/0day COMPILER=gcc-9.3.0 make.cross C=1 CF='-fdiagnostic-prefix -D__CHECK_ENDIAN__' ARCH=powerpc
>
> If you fix the issue, kindly add following tag as appropriate
> Reported-by: kernel test robot <lkp@intel.com>

The mentioned patch is not the source of the problem, it only allows to spot it.

Christophe

>
>
> "sparse warnings: (new ones prefixed by >>)"
>>> drivers/w1/slaves/w1_ds28e04.c:342:13: sparse: sparse: incorrect type in initializer (different address spaces) @@ expected char [noderef] __user *_pu_addr @@ got char *buf @@
> drivers/w1/slaves/w1_ds28e04.c:342:13: sparse: expected char [noderef] __user *_pu_addr
> drivers/w1/slaves/w1_ds28e04.c:342:13: sparse: got char *buf
>>> drivers/w1/slaves/w1_ds28e04.c:356:13: sparse: sparse: incorrect type in initializer (different address spaces) @@ expected char const [noderef] __user *_gu_addr @@ got char const *buf @@
> drivers/w1/slaves/w1_ds28e04.c:356:13: sparse: expected char const [noderef] __user *_gu_addr
> drivers/w1/slaves/w1_ds28e04.c:356:13: sparse: got char const *buf
> --
> drivers/gpu/drm/radeon/radeon_ttm.c:933:21: sparse: sparse: cast removes address space '__user' of expression
> drivers/gpu/drm/radeon/radeon_ttm.c:933:21: sparse: sparse: cast removes address space '__user' of expression
>>> drivers/gpu/drm/radeon/radeon_ttm.c:933:21: sparse: sparse: incorrect type in initializer (different address spaces) @@ expected unsigned int [noderef] __user *_pu_addr @@ got unsigned int [usertype] * @@
> drivers/gpu/drm/radeon/radeon_ttm.c:933:21: sparse: expected unsigned int [noderef] __user *_pu_addr
> drivers/gpu/drm/radeon/radeon_ttm.c:933:21: sparse: got unsigned int [usertype] *
> drivers/gpu/drm/radeon/radeon_ttm.c:933:21: sparse: sparse: cast removes address space '__user' of expression
>
> vim +342 drivers/w1/slaves/w1_ds28e04.c
>
> fa33a65a9cf7e2 Greg Kroah-Hartman 2013-08-21 338
> fa33a65a9cf7e2 Greg Kroah-Hartman 2013-08-21 339 static ssize_t crccheck_show(struct device *dev, struct device_attribute *attr,
> fa33a65a9cf7e2 Greg Kroah-Hartman 2013-08-21 340 char *buf)
> fbf7f7b4e2ae40 Markus Franke 2012-05-26 341 {
> fbf7f7b4e2ae40 Markus Franke 2012-05-26 @342 if (put_user(w1_enable_crccheck + 0x30, buf))
> fbf7f7b4e2ae40 Markus Franke 2012-05-26 343 return -EFAULT;
> fbf7f7b4e2ae40 Markus Franke 2012-05-26 344
> fbf7f7b4e2ae40 Markus Franke 2012-05-26 345 return sizeof(w1_enable_crccheck);
> fbf7f7b4e2ae40 Markus Franke 2012-05-26 346 }
> fbf7f7b4e2ae40 Markus Franke 2012-05-26 347
> fa33a65a9cf7e2 Greg Kroah-Hartman 2013-08-21 348 static ssize_t crccheck_store(struct device *dev, struct device_attribute *attr,
> fbf7f7b4e2ae40 Markus Franke 2012-05-26 349 const char *buf, size_t count)
> fbf7f7b4e2ae40 Markus Franke 2012-05-26 350 {
> fbf7f7b4e2ae40 Markus Franke 2012-05-26 351 char val;
> fbf7f7b4e2ae40 Markus Franke 2012-05-26 352
> fbf7f7b4e2ae40 Markus Franke 2012-05-26 353 if (count != 1 || !buf)
> fbf7f7b4e2ae40 Markus Franke 2012-05-26 354 return -EINVAL;
> fbf7f7b4e2ae40 Markus Franke 2012-05-26 355
> fbf7f7b4e2ae40 Markus Franke 2012-05-26 @356 if (get_user(val, buf))
> fbf7f7b4e2ae40 Markus Franke 2012-05-26 357 return -EFAULT;
> fbf7f7b4e2ae40 Markus Franke 2012-05-26 358
> fbf7f7b4e2ae40 Markus Franke 2012-05-26 359 /* convert to decimal */
> fbf7f7b4e2ae40 Markus Franke 2012-05-26 360 val = val - 0x30;
> fbf7f7b4e2ae40 Markus Franke 2012-05-26 361 if (val != 0 && val != 1)
> fbf7f7b4e2ae40 Markus Franke 2012-05-26 362 return -EINVAL;
> fbf7f7b4e2ae40 Markus Franke 2012-05-26 363
> fbf7f7b4e2ae40 Markus Franke 2012-05-26 364 /* set the new value */
> fbf7f7b4e2ae40 Markus Franke 2012-05-26 365 w1_enable_crccheck = val;
> fbf7f7b4e2ae40 Markus Franke 2012-05-26 366
> fbf7f7b4e2ae40 Markus Franke 2012-05-26 367 return sizeof(w1_enable_crccheck);
> fbf7f7b4e2ae40 Markus Franke 2012-05-26 368 }
> fbf7f7b4e2ae40 Markus Franke 2012-05-26 369
>
> ---
> 0-DAY CI Kernel Test Service, Intel Corporation
> https://lists.01.org/hyperkitty/list/kbuild-all@lists.01.org
>