Re: Regression from 3.4.9 to 3.4.16 "stable" kernel

[Greg Kroah-Hartman <gregkh@linuxfoundation.org>]

On Tue, Oct 30, 2012 at 12:53:06AM -0400, Mark Lord wrote:
> On 12-10-29 07:03 PM, Greg Kroah-Hartman wrote:
> > On Mon, Oct 29, 2012 at 07:00:54PM -0400, Mark Lord wrote:
> >> There's something else very wrong when going from 3.4.9 to 3.4.16.
> >> I've done it on two machines here, one the AMD-450 server (64-bit),
> >> and the other my main notebook (Core2duo 32-bit-PAE).
> >>
> >> Both systems feel much more sluggish than usual with 3.4.16 running.
> >> Reverted them both back to earlier kernels (3.4.9, 3.4.4-PAE),
> >> and the usual responsive feel has returned.
> >>
> >> Vague, I know, but something bad happened in there somewhere.
> > 
> > That's too vague for me to do anything with, sorry.  Bisection would be
> > good if you can figure out how to measure this.
> 
> Well, I'd bet Donkeys to Daises that reverting the kernel/sched.c changes
> will probably fix the responsiveness, but I haven't done that yet.
> I've lost enough time already debugging the other issues.
> 
> This is more just an indication that perhaps -stable patches need better review
> than they're getting.  Take the setup.c breakage: as soon as I pointed it out,
> a few people jumped in with knowledge that it was broken, and that patches
> existed to fix it.

There will always be bugs, fixing them quickly is the best that we can
do.

> That kind of thing should be happening before a -stable release,
> though I don't know how you would get the Right People to look
> at this stuff then rather than after the fact.  Maybe a topic
> for a future kernel summit or something.

I send patches to everyone involved, and there's a -rc period where
people are _supposed_ to test things out.  If you know of a better way
to get other people to test and review, please let me know, this is the
best that we have come up with so far.

thanks,

greg k-h