On 8/11/2014 8:46 AM, Benjamin Herrenschmidt wrote: > On Tue, 2014-08-05 at 15:51 +0100, One Thousand Gnomes wrote: >> On Tue, 05 Aug 2014 20:12:09 +0530 >> Vishal Mansur <vman...@linux.vnet.ibm.com> wrote: >> >>> EEH kernel services are inconsistently exported by the >>> kernel. eeh_check_failure is exported for any use, but >>> eeh_dev_check_failure is exported only for GPL use. >>> While eeh_check_failure is implemented for a specific >>> purpose to be used by services such as readl, it is >>> not suited for a purpose where caller needs eeh status. >>> This functionality is provided by eeh_dev_check_failure. >>> >>> This patch relaxes the export for eeh_dev_check_failure >>> to make it consistent with eeh_check_failure() and >>> usable by non-GPL modules. >> >> The GPL covers all derivative works. Tweaking this doesn't magically >> allow you to use the feature in non GPL code. Your legal department can I >> am sure explain in detail further. > > This is an interesting case... I assume this has to do with a well known > GPU manufacturer... > > The PCI APIs are generally exported in such a way that a non-GPL driver > can use them (regardless of whether one considers a non-GPL driver to be > legal here or not, this is besides the point). > > eeh_dev_check_failure() can be considered as powerpc specific extension > of the PCI API for use by PCI drivers and as such, it *could* be > construed that we should be consistent (and consistent with > eeh_check_failure()) and expose it as an EXPORT_SYMBOL without the GPL > suffix. > > So I'm somewhat tempted to take this patch, but Vishal, the driver in > question could, I suppose, as a workaround, use a readl to some scratch > register of some description, no ?
Ben, calling readl to some scratch register will be same as calling eeh_check_failure, caller will not be able to get eeh status. Hence for the purpose where caller wants to know eeh status during a bad register read, it can not be worked around using readl. Thanks, Vishal > > Cheers, > Ben. > >> Alan >> -- >> To unsubscribe from this list: send the line "unsubscribe linux-kernel" in >> the body of a message to majord...@vger.kernel.org >> More majordomo info at http://vger.kernel.org/majordomo-info.html >> Please read the FAQ at http://www.tux.org/lkml/ > > _______________________________________________ Linuxppc-dev mailing list Linuxppc-dev@lists.ozlabs.org https://lists.ozlabs.org/listinfo/linuxppc-dev
