Re: [PATCH v5 1/2] iommu - Enable debugfs exposure of IOMMU driver internals

[Gary R Hook <gary.hook@amd.com>]

On 05/08/2018 03:42 PM, Joe Perches wrote:
> On Tue, 2018-05-08 at 15:07 -0500, Gary R Hook wrote:
>> On 05/08/2018 01:48 PM, Joe Perches wrote:
>>> On Tue, 2018-05-08 at 12:08 -0500, Hook, Gary wrote:
>>>> On 5/7/2018 6:47 PM, kbuild test robot wrote:
>>>>>
>>>>> All error/warnings (new ones prefixed by >>):
>>>>>
>>>>>       In file included from include/linux/intel-iommu.h:32:0,
>>>>>                        from drivers/gpu/drm/i915/i915_drv.h:41,
>>>>>                        from drivers/gpu/drm/i915/i915_oa_bxt.c:31:
>>>>>       include/linux/iommu.h: In function 'iommu_debugfs_new_driver_dir':
>>>>>>> include/linux/iommu.h:706:8: error: parameter name omitted
>>>>>
>>>>>        struct dentry *iommu_debugfs_new_driver_dir(char *) {};
>>>>>               ^~~~~~
>>>>>       In file included from include/linux/intel-iommu.h:32:0,
>>>>>                        from drivers/gpu/drm/i915/i915_drv.h:41,
>>>>>                        from drivers/gpu/drm/i915/i915_oa_bxt.c:31:
>>>>>>> include/linux/iommu.h:706:8: warning: control reaches end of non-void function [-Wreturn-type]
>>>>>
>>>>>        struct dentry *iommu_debugfs_new_driver_dir(char *) {};
>>>>>               ^~~~~~
>>>>>
>>>>> vim +706 include/linux/iommu.h
>>>>>
>>>>>       700	
>>>>>       701	#ifdef CONFIG_IOMMU_DEBUGFS
>>>>>       702	void iommu_debugfs_setup(void);
>>>>>       703	struct dentry *iommu_debugfs_new_driver_dir(char *);
>>>>>       704	#else
>>>>>       705	static inline void iommu_debugfs_setup(void) {}
>>>>>     > 706	struct dentry *iommu_debugfs_new_driver_dir(char *) {};
>>>>>       707	#endif
>>>>>       708	
>>>>
>>>> I have no problems with adding parameter names. But
>>>> scripts/checkpatch.pl doesn't seem to check for this, nor require it.
>>>> Should checkpatch be updated?
>>>
>>> I'm pretty sure that's not feasible.
>>
>> Ugh. This is a definition, not a declaration. My bad. Which is likely
>> why I decided to apologize up front.
>>
>>> And when the compiler tells you you've stuffed up some
>>> syntactical bit, why should checkpatch duplicate the
>>> output error message too?
>>
>> Well, that's the point: neither the 4.8 nor 5.4 compiler complained
>> about this.
> 
> Perhaps because CONFIG_IOMMU_DEBUGFS was set in the .config
> for all the compilation previously performed?

Well, you'd think maybe so, but I forced a recompilation of that one 
file (i915_oa_bxt.c) and no complaint with 5.4. Weird.

Ah, well. Onward to patch version 6.

Thanks again.