Hi Arnd,

I love your patch! Yet something to improve:

[auto build test ERROR on v4.17-rc2]
[cannot apply to sound/for-next asoc/for-next arm-soc/for-next next-20180424]
[if your patch is applied to the wrong git tree, please drop us a note to help improve the system]

url:    https://github.com/0day-ci/linux/commits/Baolin-Wang/Fix-year-2038-issue-for-sound-subsystem/20180426-010145
config: i386-randconfig-n0-201816 (attached as .config)
compiler: gcc-7 (Debian 7.3.0-16) 7.3.0
reproduce:
        # save the attached .config to linux build tree
        make ARCH=i386 

All errors (new ones prefixed by >>):

>> sound/core/pcm_native.c:2827:25: error: field 'tstamp' has incomplete type
     struct compat_timespec tstamp;
                            ^~~~~~
>> sound/core/pcm_native.c:2829:25: error: field 'audio_tstamp' has incomplete type
     struct compat_timespec audio_tstamp;
                            ^~~~~~~~~~~~

vim +/tstamp +2827 sound/core/pcm_native.c

^1da177e Linus Torvalds 2005-04-16  2822  
28282c58 Arnd Bergmann  2018-04-24  2823  struct snd_pcm_mmap_status32 {
28282c58 Arnd Bergmann  2018-04-24  2824  	s32 state;
28282c58 Arnd Bergmann  2018-04-24  2825  	s32 pad1;
28282c58 Arnd Bergmann  2018-04-24  2826  	u32 hw_ptr;
28282c58 Arnd Bergmann  2018-04-24 @2827  	struct compat_timespec tstamp;
28282c58 Arnd Bergmann  2018-04-24  2828  	s32 suspended_state;
28282c58 Arnd Bergmann  2018-04-24 @2829  	struct compat_timespec audio_tstamp;
28282c58 Arnd Bergmann  2018-04-24  2830  } __attribute__((packed));
28282c58 Arnd Bergmann  2018-04-24  2831  

:::::: The code at line 2827 was first introduced by commit
:::::: 28282c58cc57dade81f0f5c5a310647a10bd17c3 ALSA: move snd_pcm_ioctl_sync_ptr_compat into pcm_native.c

:::::: TO: Arnd Bergmann <arnd@arndb.de>
:::::: CC: 0day robot <fengguang.wu@intel.com>

---
0-DAY kernel test infrastructure                Open Source Technology Center
https://lists.01.org/pipermail/kbuild-all                   Intel Corporation