[Crash-utility] [PATCH] crash: Do not use bt -t flag in panic_search()

[Dave Anderson]

----- Original Message -----
> On Mon, 03 Aug 2015 12:30:22 -0400
> Dave Anderson <anderson at prospeed.net> wrote:
> 
> > 
> >     
> > Ah, it must be because of the common user-kernel virtual address space on
> > s390x?
> 
> Yes we have overlapping virtual address ranges for kernel and user space and user
> space registers are stored at the start of the kernel stack.
> 
> But I am not sure, if that is the reason here (have to verify this).
> 
> Doesn't the -t option check all the stack memory and looks for valid symbol
> addresses? So IMO everything found there could be by chance the address
> of panic. Why is this no problem on x86?

I'm not sure what you mean.  How could it be there by chance?  Are you talking
about a highly unlikely situation where a user-space exception frame at the top
of the kernel stack happens to have a register containing a kernel virtual address
that's within the panic() function?

Dave

> 
> Michael
> 
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