On Mon, Feb 18, 2013 at 11:13:06PM +0100, Borislav Petkov wrote: > On Mon, Feb 18, 2013 at 01:54:34PM -0800, Greg KH wrote: > > Because sysfs is "one value per file" the lack of a file showing up > > shouldn't cause any userspace tools any problems, that is why we did > > things this way. > > > > But, of course, userspace programmers do know how to mess things up... > > How about what I proposed earlier to Felipe: > > -- > diff --git a/drivers/edac/edac_mc_sysfs.c b/drivers/edac/edac_mc_sysfs.c > index 0ca1ca71157f..d2eef76d1d46 100644 > --- a/drivers/edac/edac_mc_sysfs.c > +++ b/drivers/edac/edac_mc_sysfs.c > @@ -704,7 +704,7 @@ static ssize_t mci_sdram_scrub_rate_show(struct device *dev, > int bandwidth = 0; > > if (!mci->get_sdram_scrub_rate) > - return -ENODEV; > + return sprintf(data, "N/A"); > > bandwidth = mci->get_sdram_scrub_rate(mci); > if (bandwidth < 0) { > > -- > > Would that hurt the sysfs policy? In this case we *can* read the file > and it correctly tells us that scrub rate reading is not supported > instead of having a number there. > > Hmm. I don't know, it depends on if userspace can handle this properly or not. What tools rely on this sysfs file? WHat happens when they get a non-number in the file? thanks, greg k-h -- To unsubscribe from this list: send the line "unsubscribe linux-scsi" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html