[Crash-utility] [PATCH] Improve error handling when architecture doesn't match

[Dave Anderson]

Dave Anderson wrote:
> Bernhard Walle wrote:
> 
>> * Dave Anderson <anderson at redhat.com> [2007-12-21 17:20]:
>>
>>> Looks reasonable.
>>>
>>> BTW, since is_netdump() gets called twice, first
>>> directly and then via is_kdump(), do the error
>>> messages get printed twice?
>>
>>
>>
>> Yes. But I don't think it's a problem, is it?
>>
>>
>> Thanks,
>>    Bernhard
> 
> 
> No, just looks funny.  Anyway, I'll run with it
> from here -- nice improvement.
> 
> Thanks,
>   Dave
> 

Actually this patch has just turned up different issues
that have to be handled, because the e_type and e_phnum
get deferred until after the e_machine and endianness
are checked.

Among them the fact that an i386 xen guest core file
taken by an x86_64 host has the e_machine type set
to x86_64 (don't ask me why they did that...), and has
an e_phnum of 0.  Anyway, that requires the e_phnum
to be checked *before* the machine type and endianness.

And another, since the e_type doesn't get checked
until *after* the machine type and endianness,
it allows the vmlinux file (ET_EXEC) to get passed
through, which can generate a bogus error message
about the vmlinux file!

And there's probably others...

There was a method to my madness in the way it's written
now.  I'm going to have to spend some more time with
this because I don't want to introduce false alarms
or print error messages that don't make any sense...

Dave