kexec/kdump produces incomplete dump files with kernel 2.6.20 + CONFIG_HIGHMEM64G

Dave Anderson anderson at
Fri Oct 17 13:58:36 EDT 2008

> Well, without following the thread, I had a similar error and in my
> case it was that PAE was missing in the capture kernel. That's why I
> asked. I think that is wrong here, but I still wanted to mention that
> case (and I don't have time to read all the mails related to that topic
> in the crash mailing list, sorry).
> Regards,
> Bernhard

Well that makes perfect sense -- the upper bit gets stripped in
the 32-bit PTE and the wrong location gets mapped.  I was looking
at the fs/vmcore.c code for something to that effect, and I just
presumed his capture kernel was PAE.  Looking back at the thread,
the only thing I see is this:

  "my "capture kernel" is just the standard Ubuntu kernel
   (with 1G kernel / 3G user)."

Whatever that means... 

So Kevin, that's the first thing to check.

Thanks Bernhard,

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