Re: crash binary for latest unreleased kernel

[Joe Smith]

I happen to look at the patches for the crash binary and came across
this log entry from Jan 19. I am also using 4.15-rc kernel. Not
knowing anything about crash it is hard to even attempt to fix it.

Initial pass for support of kernel page table isolation. The x86_64

"bt" command may indicate "bt: cannot transition from exception stack
to current process stack" if the crash callback NMI occurred while an
active task was running on the new entry trampoline stack.  This has
only been tested on the RHEL7 backport of the upstream patch because
as of this commit, crash does not run on 4.15-rc kernels.  Further
changes may be required for upstream kernels, and distributions that
implement the kernel changes differently than upstream.
(anderson@xxxxxxxxxx)

On Fri, Jan 26, 2018 at 8:48 PM, Mike Galbraith <efault@xxxxxx> wrote:
> On Fri, 2018-01-26 at 20:38 -0800, Randy Dunlap wrote:
>> On 01/26/2018 08:32 PM, Mike Galbraith wrote:
>> > On Fri, 2018-01-26 at 12:52 -0800, Joe Smith wrote:
>> >> Hi,
>> >>
>> >> I am doing development on the latest unreleased kernel on a system
>> >> running ubuntu 16.04. I can not get crash dump to be saved or use
>> >> crash on the live system. I have tried compiling crash on the system.
>> >>
>> >> What is the trick to do development on the latest kernel using a
>> >> system installed with old release.
>> >
>> > You have to either be motivated enough to fix crash and friends up as
>> > they get busted, or lazy enough to wait for maintainers to do so for
>> > you.  I've done a bit of both, but the later is my favorite :)
>>
>> :)
>>
>> Is it mostly structure updates or is it partly randomized layout of
>> structs?  or something totally different?
>
> The stuff I've fixed up has been trivial renames and whatnot, operative
> word being trivial, easy to find based on gripage.  If I don't find it
> quickly, I usually decide to not need it _that_ badly, go with plan B.
>
>         -Mike



-- 
JS