Re: [PATCH 11/16] powerpc: vio_cmo: use dev_groups and not dev_attrs for bus_type

On Fri, Jun 09, 2017 at 09:23:10PM +1000, Michael Ellerman wrote:

Greg Kroah-Hartman [off-list ref] writes:

quoted

On Fri, Jun 09, 2017 at 08:53:22AM +1000, Michael Ellerman wrote:

quoted

Greg Kroah-Hartman [off-list ref] writes:

quoted

On Thu, Jun 08, 2017 at 11:12:10PM +1000, Michael Ellerman wrote:

quoted

Greg Kroah-Hartman [off-list ref] writes:

quoted

The dev_attrs field has long been "depreciated" and is finally being
removed, so move the driver to use the "correct" dev_groups field
instead for struct bus_type.

Cc: Benjamin Herrenschmidt <benh@kernel.crashing.org>
Cc: Paul Mackerras <redacted>
Cc: Michael Ellerman <mpe@ellerman.id.au>
Cc: Vineet Gupta <redacted>
Cc: Bart Van Assche <redacted>
Cc: Robin Murphy <robin.murphy@arm.com>
Cc: Joerg Roedel <redacted>
Cc: Johan Hovold <johan@kernel.org>
Cc: Alexey Kardashevskiy <redacted>
Cc: Krzysztof Kozlowski <krzk@kernel.org>
Cc: <redacted>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
---
 arch/powerpc/platforms/pseries/vio.c | 37 +++++++++++++++++++++---------------
 1 file changed, 22 insertions(+), 15 deletions(-)

This one needed a bit more work to get building, the incremental diff is
below. We need a forward declaration of name, devspec and modalias,
which is a bit weird, but that's how the code is currently structured.
And there's dev and bus attributes with the same name, so that needed an
added "bus".

I booted v2 of patch 10 and this one and everything looks identical to
upstream.

Ah, many thanks, this was on my todo list to fix up today.

But you renamed the sysfs files when you added "bus" to the function
names, are you sure you want to do that?  I don't mind, but if you
happen to have userspace tools that look at those files, they just broke
:(

Ugh crap, no that won't work.

I didn't see it when I tested because my machine doesn't have the CMO
feature enabled.

I guess we have to open code some of the BUS_ATTR_RO() etc. so we can
avoid the name clash.

Or split it into multiple files, I've solved this that way in the past.
You shouldn't have to "open code" BUS_ATTR_RO().

It just requires one use of __ATTR(), which seems simpler than splitting
the file in two.

Ah, yes, nice work, thanks.  If you wanted to be really "tricky", you
could just use __ATTR_RO() there, but I'll leave it as-is :)

Let's see what 0-day says about this version.

Many thanks for working on this, much appreciated.

greg k-h