Re: [PATCH] arm:traps: Don't print stack or raw PC/LR values in backtraces

[Josh Poimboeuf]

On Fri, Oct 09, 2020 at 09:08:50AM +0100, Russell King - ARM Linux admin wrote:
> On Fri, Oct 09, 2020 at 03:59:57PM +0800, Xiaoming Ni wrote:
> > Printing raw pointer values in backtraces has potential security
> > implications and are of questionable value anyway.
> > 
> > This patch follows x86 and arm64's lead and removes the "Exception stack:"
> > dump from kernel backtraces:
> > 	commit a25ffd3a6302a6 ("arm64: traps: Don't print stack or raw
> > 	 PC/LR values in backtraces")
> > 	commit 0ee1dd9f5e7eae ("x86/dumpstack: Remove raw stack dump")
> > 	commit bb5e5ce545f203 ("x86/dumpstack: Remove kernel text
> > 	 addresses from stack dump")
> > 
> > Signed-off-by: Xiaoming Ni <nixiaoming@xxxxxxxxxx>
> 
> I am really not happy about this - it hurts at least my ability to
> debug the kernel when people post oopses to the mailing list. If
> people wish to make the kernel harder to debug, and are prepared
> to be told "your kernel is undebuggable" then this patch is fine.

At least on x86 we've had this for four years now, without any apparent
harm to debugability.  scripts/faddr2line helps.

-- 
Josh