On Tue, Sep 16, 2014 at 01:52:47PM -0700, Darren Hart wrote: > On Tue, Sep 16, 2014 at 01:54:25PM +0200, Frans Klaver wrote: > > On Mon, Sep 15, 2014 at 11:55 PM, Frans Klaver <fransklaver@xxxxxxxxx> wrote: > > > On Mon, Sep 15, 2014 at 02:51:25PM -0700, Greg Kroah-Hartman wrote: > > >> On Mon, Sep 15, 2014 at 02:49:02PM -0700, Darren Hart wrote: > > >> > > > >> > This patch is fine as is. However, Greg has supported propogating the error code > > >> > through to the sysfs interface (if I understand him correctly on an earlier post > > >> > to this list). This would require an addition change to this patch would > > >> > propogated the get_cpufv error code in show_available_cpuv(), show_cpuv(), and > > >> > store_cpuv(). As it is, we return -ENODEV on any failure, where an ACPI call > > >> > error should probably return -ENXIO as I understand it. > > >> > > >> I really have no idea at this point in time what to recommend. How > > >> about just stick with what is happening today so that: > > >> > > >> > However, there was a rather famous change in error code handling in which pulse > > >> > audio broke and Linus was very upset with one of his maintainers. > > >> > > >> That doesn't happen :) > > > > > > So if I interpret that correctly, we're dropping the last patch > > > (ENODEV -> ENXIO) from the series? That's fine by me. As mentioned > > > earlier, I already saw something else break because I returned ENXIO > > > instead of ENODEV. > > > > > > Maybe it's a good idea to try and document the expected behavior > > > somewhere, if even Greg isn't sure what to do. > > > > For good measure: > > > > v2 will not change the return values at the sysfs interface, meaning > > we will always return -ENODEV on error. I am going to try to keep as > > much internal functions propagating errors as possible though, unless > > someone strongly disagrees. > > > > Thanks, > > Frans > > I cornered Linus today and asked about this specifically. The policy is this: > > Don't change the sysfs return codes without good reason. A good reason could be > a real bug or problem with the return codes. It could also be to consolidate > error handling which makes things more uniform, etc. > > If this results in broken userspace, the maintainer will revert the change. Alright, that is basically what I was expecting it to be. As it happens, this also means that we'll have to decide what to do about returning -EIO/-ENODEV/rv in show_sys_acpi and store_sys_acpi. The latter was changed by Paul Bolle's "eeepc-laptop: simplify parse_arg()". The return value of these functions is propagated to the sysfs interface. > This is probably a good thing to add to sysfs-rules.txt. I'll prepare a patch. Agreed. While I was removing the patches changing the sysfs error behavior, I also noticed that eeepc-laptop.c doesn't really seem to handle errors uniformly. In some cases the callers of get_acpi and set_acpi don't even seem to consider that these functions may return an error code (e.g. eeepc_hotk_thaw()). I'd fix those in a new series though. Frans -- To unsubscribe from this list: send the line "unsubscribe platform-driver-x86" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html
