Re: [PATCH] platform/chrome: fix reference leak on failed device registration

[Guangshuo Li]

Hi,

On Fri, 17 Apr 2026 at 16:47, kernel test robot <lkp@xxxxxxxxx> wrote:
>
> Hi Guangshuo,
>
> kernel test robot noticed the following build errors:
>
> [auto build test ERROR on chrome-platform/for-next]
> [also build test ERROR on chrome-platform/for-firmware-next linus/master v7.0 next-20260416]
> [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/Guangshuo-Li/platform-chrome-fix-reference-leak-on-failed-device-registration/20260416-135638
> base:   https://git.kernel.org/pub/scm/linux/kernel/git/chrome-platform/linux.git for-next
> patch link:    https://lore.kernel.org/r/20260415175038.3633384-1-lgs201920130244%40gmail.com
> patch subject: [PATCH] platform/chrome: fix reference leak on failed device registration
> config: x86_64-randconfig-013-20260417 (https://download.01.org/0day-ci/archive/20260417/202604171609.wl8JLCit-lkp@xxxxxxxxx/config)
> compiler: clang version 20.1.8 (https://github.com/llvm/llvm-project 87f0227cb60147a26a1eeb4fb06e3b505e9c7261)
> reproduce (this is a W=1 build): (https://download.01.org/0day-ci/archive/20260417/202604171609.wl8JLCit-lkp@xxxxxxxxx/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@xxxxxxxxx>
> | Closes: https://lore.kernel.org/oe-kbuild-all/202604171609.wl8JLCit-lkp@xxxxxxxxx/
>
> All errors (new ones prefixed by >>):
>
> >> drivers/platform/chrome/chromeos_pstore.c:131:3: error: use of undeclared identifier 'ret'
>      131 |                 ret = platform_device_register(&chromeos_ramoops);
>          |                 ^
>    drivers/platform/chrome/chromeos_pstore.c:132:7: error: use of undeclared identifier 'ret'
>      132 |                 if (ret)
>          |                     ^
>    drivers/platform/chrome/chromeos_pstore.c:135:10: error: use of undeclared identifier 'ret'
>      135 |                 return ret;
>          |                        ^
>    3 errors generated.
>
>
> vim +/ret +131 drivers/platform/chrome/chromeos_pstore.c
>
>    119
>    120  static int __init chromeos_pstore_init(void)
>    121  {
>    122          bool acpi_dev_found;
>    123
>    124          if (ecc_size > 0)
>    125                  chromeos_ramoops_data.ecc_info.ecc_size = ecc_size;
>    126
>    127          /* First check ACPI for non-hardcoded values from firmware. */
>    128          acpi_dev_found = chromeos_check_acpi();
>    129
>    130          if (acpi_dev_found || dmi_check_system(chromeos_pstore_dmi_table)) {
>  > 131                  ret = platform_device_register(&chromeos_ramoops);
>    132                  if (ret)
>    133                          platform_device_put(&chromeos_ramoops);
>    134
>    135                  return ret;
>    136          }
>    137
>    138          return -ENODEV;
>    139  }
>    140
>
> --
> 0-DAY CI Kernel Test Service
> https://github.com/intel/lkp-tests/wiki

Yes, the build error is because in the first version I accidentally
forgot to declare the local variable ret in chromeos_pstore_init().

Sorry for the oversight, and thanks for the report.

Also, the underlying issue here appears to be related to the
platform_device_register() core/API behavior. We are currently
discussing in another similar case whether the better fix, if any,
should be made in the core/API code rather than in individual callers:

https://patchew.org/linux/20260415174159.3625777-1-lgs201920130244@xxxxxxxxx/

Once that discussion reaches a conclusion, we will revisit this and
make the appropriate fix if needed.

Thanks,
Guangshuo