Re: [PATCH 2/4] powerpc/vas: Fix cleanup when VAS is not configured

From: Michael Ellerman
Date: Mon Feb 12 2018 - 22:25:18 EST


Sukadev Bhattiprolu <sukadev@xxxxxxxxxxxxxxxxxx> writes:

> Michael Ellerman [mpe@xxxxxxxxxxxxxx] wrote:
>> Sukadev Bhattiprolu <sukadev@xxxxxxxxxxxxxxxxxx> writes:
>>
>> > When VAS is not configured in the system, make sure to remove
>> > the VAS debugfs directory and unregister the platform driver.
>> >
>> > Signed-off-by: Sukadev Bhattiprolu <sukadev@xxxxxxxxxxxxxxxxxx>
>> ...
>> > diff --git a/arch/powerpc/platforms/powernv/vas.c b/arch/powerpc/platforms/powernv/vas.c
>> > index aebbe95..f83e27d8 100644
>> > --- a/arch/powerpc/platforms/powernv/vas.c
>> > +++ b/arch/powerpc/platforms/powernv/vas.c
>> > @@ -169,8 +169,11 @@ static int __init vas_init(void)
>> > found++;
>> > }
>> >
>> > - if (!found)
>> > + if (!found) {
>> > + platform_driver_unregister(&vas_driver);
>> > + vas_cleanup_dbgdir();
>> > return -ENODEV;
>> > + }
>>
>> The better patch would be to move the call to vas_init_dbgdir() down
>> here, where we know we have successfully registered the driver.
>
> Well, when VAS is configured, init_vas_instance() expects the top level
> "vas" debugfs dir to already be setup.

OK.

> We could have each init_vas_instance() assume it is the first and
> unconditionally call vas_init_dbgdir(). vas_init_dbgdir() could make
> sure to initialize only once.

Yeah that looks like a good solution.

cheers