backtrace not working on mainline x86_64

[Jose R. Santos]

bibo,mao wrote:

>In recent x86_64, process kernel stack is different from trap stack, I 
>modify runtime/stack.c _stp_stack_sprint() function, the original is
>	 __stp_stack_sprint (str, (unsigned long *)&REG_SP(regs), verbose, 0);
>	 __stp_stack_sprint (str, (unsigned long *)REG_SP(regs), verbose, 0);
>
>It works well for x86_86 in recent kernel version, this is only 
>temporary method.
>  
>
That works for me.

What would be a good permanent fix for this?  Should check for X86_64 
and Kernel version be added to _stp_stack_sprint() function?

-JRS