[Crash-utility] Re: user_regs_struct is not a VALID_STRUCT ?

[Dave Anderson]

Rachita Kothiyal wrote:

> Hi Dave
>
> I was running crash to analyse a vmcore generated by a 2.6.18-rc4 kernel. Even though 'struct user_regs_struct' is defined in the kernel, STRUCT_SIZE_INIT() gets a -1 for it (reflects in help -o). Of what I understand, when we call STRUCT_SIZE_INIT, crash calls gdb and sends a request to look up the symbol table for this structure's entry, which gdb is not able to find. Hence returns a -1. I verified that it was doing this when I ran gdb over crash.
>
> I dont understand why this is..am I missing something here ?
> Could you please suggest some way I could debug this more...
>
> Thanks
> Rachita

You're not missing anything -- the vmlinux file is...

This has been true AFAICT in all 2.6 x86_64 kernels -- for
whatever reason the x86_64 user_regs_struct debug info
doesn't get added in.  Your guess as to why is as good
as mine.

In any case, since its layout hasn't ever changed since
its inception, it's probably safe to hardwire the offsets if
they cannot be determined from the vmlinux file.

Dave