Re: The sheer number of sparse warnings in the kernel

Greg KH
2014-02-26T23:27:24Z

On Wed, Feb 26, 2014 at 02:49:26PM -0800, H. Peter Anvin wrote:
> The number of sparse errors in the current kernel is staggering, and it
> makes sparse a lot less valuable of a tool that it otherwise could be.
> On a build of x86-64 allyesconfig I'm getting 20,676 sparse messages.
> Out of those, 12,358 come from linux/err.h. Given that the latter
> basically spams *everything*, I can only conclude that almost noone uses
> sparse unless they have a filter script.

What errors are you seeing from err.h? I don't see those when building
different subdirectories with sparse (which is how I normally use it.)

And what version of sparse are you running:
$ sparse --version
v0.4.5-rc1-407-g345e8943fc36

> So a lot of these are certainly nuisance problems, like the
> <linux/err.h> stuff which has to do with the handling of error values,
> but some of these look like real bugs.
>
> What do we need to do to actually make our tools be able to do work for
> us? Newbie projects to clean up? Trying to get the larger Linux
> companies to put resources on it?

It's not the easiest "newbie" project as usually the first reflex to
"just cast it away" is wrong for a lot of sparse warnings. I know this
from people trying to fix up the sparse warnings in drivers/staging/

thanks,

greg k-h