[Crash-utility] enhance bt command

[Dave Anderson]

Ming Zhang wrote:

> my English sucks...
> 
> this is what i got. my side size-512 or size-1024 also works. just stuff
> like dentry cache or inode cache does not work.
> 
> 
> crash> rd 10078b2bca0 2
>      10078b2bca0:  000001007877c8d4 00000100710fd5c8   ..wx.......q....
> crash> rd -S 10078b2bca0 2
>      10078b2bca0:  [dentry_cache]   00000100710fd5c8 
> crash> kmem -s 10078b2bca0
> kmem: address is not allocated in slab subsystem: 10078b2bca0

No, your English is fine -- it's your command-entering that sucks!

Above, when you entered "kmem -s 10078b2bca0", you're incorrectly entering
the *address* where the dentry_cache reference (1007877c8d4) is located.
And so it's telling you that 10078b2bca0 is not allocated in the slab
subsystem, which it isn't...

But if you entered "kmem -s 1007877c8d4", you'd see the dentry_cache
information.

Dave