Date: Thu, 30 Jan 2014 10:23:02 +0100
From: Ingo Molnar <mingo@kernel.org>
To: Mathias Krause <minipli@googlemail.com>
Cc: Linus Torvalds <torvalds@linux-foundation.org>,
        "H. Peter Anvin" <hpa@zytor.com>, Richard Weinberger <richard@nod.at>,
        "H. Peter Anvin" <hpa@linux.intel.com>,
        Kees Cook <keescook@chromium.org>, Cong Ding <dinggnu@gmail.com>,
        Ingo Molnar <mingo@elte.hu>,
        Linux Kernel Mailing List <linux-kernel@vger.kernel.org>,
        Michael Davidson <md@google.com>, Thomas Gleixner <tglx@linutronix.de>,
        Wei Yongjun <yongjun_wei@trendmicro.com.cn>
Subject: Re: [GIT PULL] x86/kaslr for v3.14
Message-ID: <20140130092301.GB2862@gmail.com>
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* Mathias Krause <minipli@googlemail.com> wrote:

> On 29 January 2014 09:11, Ingo Molnar <mingo@kernel.org> wrote:
> >> But you can see that the symbol is perfectly fine:
> >>
> >>   (gdb) list *(schedule+0x45)
> >
> > Oh, cool. Thanks for that trick - this will save me quite some time in
> > the future.
> >
> > So we can strip absolute addresses just fine from oopses - cool.
> >
> > I'd even argue to strip the hex on non-randomized kernels as long as
> > there's kallsyms around, and only print hex if we don't have any
> > symbols.
> 
> Please, don't do so! I do find the hex values in the backtrace 
> *very* useful as I'm using 'objdump -wdr vmlinux | less' quite often 
> to "browse around" in the kernel binary. Grepping for addresses from 
> a backtrace works quite nicely this way. Having to lookup symbols 
> and do base-16 arithmetics in the head (or a shell, for that matter) 
> would only slow down this process. So, please leave the hex values 
> in place. They do help a lot -- at least in the non-kASLR case.

Well, if the consensus is that they help then we better make them 
correct in the KASLR case as well ...

Thanks,

	Ingo
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