Re: SYSFS "errors"

From: Borislav Petkov
Date: Mon Feb 18 2013 - 17:13:16 EST

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.



Sent from a fat crate under my desk. Formatting is fine.
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