Re: powerpc allmodconfig build broken due to commit 15863ff3b (powerpc: Make chip-id information available to userspace)

On Wed, Sep 11, 2013 at 08:02:49AM +1000, Benjamin Herrenschmidt wrote:

On Mon, 2013-09-09 at 16:55 -0700, Asai Thambi S P wrote:

quoted

On 09/08/2013 5:28 PM, Guenter Roeck wrote:

quoted

Hi all,

powerpc allmodconfig build on the latest upstream kernel results in:

ERROR: ".cpu_to_chip_id" [drivers/block/mtip32xx/mtip32xx.ko] undefined!

This is due to commit 15863ff3b (powerpc: Make chip-id information 
available to userspace).
Not surprising, as cpu_to_chip_id() is not exported.

Apart from the above error, I have a concern on the patch, purely based on the commit message.
(to be honest, I am not familiar with the ppc architecture)

Commit message of 15863ff3b has the following text.

******************
So far "/sys/devices/system/cpu/cpuX/topology/physical_package_id"
was always default (-1) on ppc64 architecture.

Now, some systems have an ibm,chip-id property in the cpu nodes in
the device tree. On these systems, we now use this information to
display physical_package_id
******************

Shouldn't the new definition of "topology_physical_package_id" apply only to those systems supporting ibm,chip-id property?

There should be no negative side effect (appart from the missing
EXPORT_SYMBOL of course). If the property is not found in the
device-tree, the new function returns -1, so it should work fine on all
systems.

Good. I submitted a patch doing just that yesterday or so.
Hope you'll accept it ;).

Thanks,
Guenter