Re: 2.6.25-rc hangs

[Christian Kujau <lists@nerdbynature.de>]

On Sun, 9 Mar 2008, Eric Sandeen wrote:
> I meant the test you were using to determine "good" from "bad" - I guess
> it was "boot up and do IO for a while to see if it hangs"

Maybe I was too confusing, let me try again:

* 2.6.24.1 was running fine for weeks (and is now)
* 2.6.25-rc3, -rc4 comes with system hang. Trying to bisect it failed
   at a really early stage:

  [check out current -git, 2.6.25-rc4)
  $ git bisect start
  $ git bisect bad          # because I know, that current -git is bad
  $ git bisect good v2.6.24 # because I know 2.6.24 is good
  [ compiling, and first reboot]
  -> failed, because hard lockup.

After rebooting to a working kernel I can now do either:

  1) mark the current one as "bad", solely on the fact that "it does not
    boot" and is "bad" per se, ignoring the fact that if the box *had*
    booted, the system hang *perhaps* did not occur. IOW, I'm marking
    it "bad" because of a totally different issue.

  2) although booting failed, I still mark it "good", which means I'm
    literally *guessing* that this current kernel (bd45ac0c5daa...)
    does NOT have the system hang and thus affecting all subsequent
    bisects. Worst case: this guess turns out to be false and I'm bisecting
    all through all ~2800 revisions without ever getting the correct "bad"
    one (because they were actually all "bad").

I tried 1), but did not get any further, as the next kernel did not boot 
either.
I tried 2), but did not get any further, as the next kernel did boot but 
locked up when I tried to use the device mapper.

Hope that's a bit better explained than before...

Thanks,
C.
-- 
BOFH excuse #58:

high pressure system failure