Hi Andrii,

I love your patch! Yet something to improve:

[auto build test ERROR on bpf-next/master]

url:    https://github.com/0day-ci/linux/commits/Andrii-Nakryiko/bpf-add-ambient-BPF-runtime-context-stored-in-current/20210710-091156
base:   https://git.kernel.org/pub/scm/linux/kernel/git/bpf/bpf-next.git master
config: nios2-randconfig-p001-20210710 (attached as .config)
compiler: nios2-linux-gcc (GCC) 9.3.0
reproduce (this is a W=1 build):
        wget https://raw.githubusercontent.com/intel/lkp-tests/master/sbin/make.cross -O ~/bin/make.cross
        chmod +x ~/bin/make.cross
        # https://github.com/0day-ci/linux/commit/e66ab92194c9a54bde72690e56df1c2602b06ae4
        git remote add linux-review https://github.com/0day-ci/linux
        git fetch --no-tags linux-review Andrii-Nakryiko/bpf-add-ambient-BPF-runtime-context-stored-in-current/20210710-091156
        git checkout e66ab92194c9a54bde72690e56df1c2602b06ae4
        # save the attached .config to linux build tree
        mkdir build_dir
        COMPILER_INSTALL_PATH=$HOME/0day COMPILER=gcc-9.3.0 make.cross O=build_dir ARCH=nios2 SHELL=/bin/bash drivers/iio/humidity/

If you fix the issue, kindly add following tag as appropriate
Reported-by: kernel test robot <lkp@intel.com>

All errors (new ones prefixed by >>):

   In file included from include/linux/bpf-cgroup.h:5,
                    from include/linux/cgroup-defs.h:22,
                    from include/linux/cgroup.h:28,
                    from include/linux/memcontrol.h:13,
                    from include/linux/swap.h:9,
                    from include/linux/suspend.h:5,
                    from include/linux/regulator/consumer.h:35,
                    from drivers/iio/humidity/hts221.h:16,
                    from drivers/iio/humidity/hts221_core.c:19:
   include/linux/bpf.h: In function 'bpf_set_run_ctx':
>> include/linux/bpf.h:1120:19: error: 'struct task_struct' has no member named 'bpf_ctx'
    1120 |  old_ctx = current->bpf_ctx;
         |                   ^~
   include/linux/bpf.h:1121:9: error: 'struct task_struct' has no member named 'bpf_ctx'
    1121 |  current->bpf_ctx = new_ctx;
         |         ^~
   include/linux/bpf.h: In function 'bpf_reset_run_ctx':
   include/linux/bpf.h:1127:9: error: 'struct task_struct' has no member named 'bpf_ctx'
    1127 |  current->bpf_ctx = old_ctx;
         |         ^~
--
   In file included from include/linux/bpf-cgroup.h:5,
                    from include/linux/cgroup-defs.h:22,
                    from include/linux/cgroup.h:28,
                    from include/linux/memcontrol.h:13,
                    from include/linux/swap.h:9,
                    from include/linux/suspend.h:5,
                    from include/linux/regulator/consumer.h:35,
                    from drivers/iio/humidity/hts221.h:16,
                    from drivers/iio/humidity/hts221_i2c.c:17:
   include/linux/bpf.h: In function 'bpf_set_run_ctx':
>> include/linux/bpf.h:1120:19: error: 'struct task_struct' has no member named 'bpf_ctx'
    1120 |  old_ctx = current->bpf_ctx;
         |                   ^~
   include/linux/bpf.h:1121:9: error: 'struct task_struct' has no member named 'bpf_ctx'
    1121 |  current->bpf_ctx = new_ctx;
         |         ^~
   include/linux/bpf.h: In function 'bpf_reset_run_ctx':
   include/linux/bpf.h:1127:9: error: 'struct task_struct' has no member named 'bpf_ctx'
    1127 |  current->bpf_ctx = old_ctx;
         |         ^~
   At top level:
   drivers/iio/humidity/hts221_i2c.c:44:36: warning: 'hts221_acpi_match' defined but not used [-Wunused-const-variable=]
      44 | static const struct acpi_device_id hts221_acpi_match[] = {
         |                                    ^~~~~~~~~~~~~~~~~


vim +1120 include/linux/bpf.h

  1115	
  1116	static inline struct bpf_run_ctx *bpf_set_run_ctx(struct bpf_run_ctx *new_ctx)
  1117	{
  1118		struct bpf_run_ctx *old_ctx;
  1119	
> 1120		old_ctx = current->bpf_ctx;
  1121		current->bpf_ctx = new_ctx;
  1122		return old_ctx;
  1123	}
  1124	

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