Re: [PATCH v4 17/17] virt: acrn: Introduce an interface for Service VM to control vCPU

Shuo A Liu
2020-09-28T06:33:27Z

On Mon 28.Sep'20 at 7:23:05 +0200, Greg Kroah-Hartman wrote:
>On Mon, Sep 28, 2020 at 12:10:07PM +0800, Shuo A Liu wrote:
>> > You just raced with userspace and lost. If you want to add attribute
>> > files to a device, use the default attribute group list, and it will be
>> > managed properly for you by the driver core.
>> >
>> > Huge hint, if a driver every has to touch a kobject, or call sysfs_*,
>> > then it is probably doing something wrong.
>>
>> Do you mean use .groups of struct miscdevice directly ?
>>
>> If yes, let me follow drivers/char/hw_random/s390-trng.c to do this.
>> BTW, few driver use the .groups directly. :)
>
>Drivers should almost never be messing with individual sysfs files. And
>this ability to use .groups is a "new" one, conversions of existing code
>that do not use them is always welcome.

OK. Thanks for the explanation. I will follow the 'new' way :)

Thanks
shuo