Re: Request for inclusion of fb90a6e93c0684 ("sched/debug: Don't dump sched debug info in SysRq-W")

[Greg KH <gregkh@linuxfoundation.org>]

On Wed, Feb 15, 2017 at 11:17:34AM +0200, Nikolay Borisov wrote:
> On 15.02.2017 11:13, Peter Zijlstra wrote:
> > On Wed, Feb 15, 2017 at 11:09:14AM +0200, Nikolay Borisov wrote:
> >> Hello,
> >>
> >> I'd like to ask for the patch in the subject to be included in stable
> >> kernels. Without it if one wants to see only the blocked stats this
> >> becomes impossible since the information dumped by sched_debug is so
> >> much that it overflows the kmsg buffer and information about blocked
> >> stats is overwritten. This is especially a problem in distro kernels
> >> which are based on 4.4 and have enabled CONFIG_SCHED_DEBUG - e.g. ubuntu.
> > 
> > Who cares about the kmsg buffer? Also, just make it bigger or disable
> > SCHED_DEBUG, as the name implies it _is_ a debug feature after all.
> 
> but what if you want to use your distro's kernel and deal with custom
> recompiles.

That doesn't make sense, if your distro wants this information, it gets
to pick what it wants.

> The kernel ought to come with sensible defaults.

You can turn it off if you have problems with it, I don't see this
meeting the stable kernel rules.

thanks,

greg k-h