[PATCH v2 5/8] drm/amdgpu: Refactor sysfs removal

[Greg KH]

On Wed, Nov 11, 2020 at 10:13:13AM -0500, Andrey Grodzovsky wrote:
> 
> On 11/10/20 12:59 PM, Greg KH wrote:
> > On Tue, Nov 10, 2020 at 12:54:21PM -0500, Andrey Grodzovsky wrote:
> > > Hi, back to this after a long context switch for some higher priority stuff.
> > > 
> > > So here I was able eventually to drop all this code and this change here https://nam11.safelinks.protection.outlook.com/?url=https:%2F%2Fcgit.freedesktop.org%2F~agrodzov%2Flinux%2Fcommit%2F%3Fh%3Damd-staging-drm-next-device-unplug%26id%3D61852c8a59b4dd89d637693552c73175b9f2ccd6&data=04%7C01%7CAndrey.Grodzovsky%40amd.com%7C7ae9e5798c7648d6dbb908d885a22c58%7C3dd8961fe4884e608e11a82d994e183d%7C0%7C0%7C637406278875513811%7CUnknown%7CTWFpbGZsb3d8eyJWIjoiMC4wLjAwMDAiLCJQIjoiV2luMzIiLCJBTiI6Ik1haWwiLCJXVCI6Mn0%3D%7C1000&sdata=aoFIsBxpLC9tBZw3E%2B8IJlNqFSq6uRgEvvciaZ6B1iw%3D&reserved=0
> > > was enough for me. Seems like while device_remove_file can handle the use
> > > case where the file and the parent directory already gone,
> > > sysfs_remove_group goes down in flames in that case
> > > due to kobj->sd being unset on device removal.
> > A driver shouldn't ever have to remove individual sysfs groups, the
> > driver core/bus logic should do it for them automatically.
> > 
> > And whenever a driver calls a sysfs_* call, that's a hint that something
> > is not working properly.
> 
> 
> 
> Do you mean that while the driver creates the groups and files explicitly
> from it's different subsystems it should not explicitly remove each
> one of them because all of them should be removed at once (and
> recursively) when the device is being removed ?

Individual drivers should never add groups/files in sysfs, the driver
core should do it properly for you if you have everything set up
properly.  And yes, the driver core will automatically remove them as
well.

Please use the default groups attribute for your bus/subsystem and this
will happen automagically.

thanks,

greg k-h