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Date: Wed, 3 Feb 2016 11:48:23 +0100
From: Ingo Molnar <mingo@kernel.org>
To: Borislav Petkov <bp@alien8.de>
Cc: "Luck, Tony" <tony.luck@intel.com>, "H. Peter Anvin" <hpa@zytor.com>,
        Thomas Gleixner <tglx@linutronix.de>,
        Andy Lutomirski <luto@amacapital.net>,
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        Steven Rostedt <rostedt@goodmis.org>, Brian Gerst <brgerst@gmail.com>,
        lkml <linux-kernel@vger.kernel.org>
Subject: Re: [RFC] Dump interesting arch/platform info
Message-ID: <20160203104823.GA21257@gmail.com>
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* Borislav Petkov <bp@alien8.de> wrote:

> On Mon, Feb 01, 2016 at 11:29:03PM +0000, Luck, Tony wrote:
> > On a high core count, multi-socket, machine I see almost 10K lines
> > of output from this.  If you add other things it will become a bit
> > of a jumble to parse.
> 
> Always thinking big... :-)
> 
> > Perhaps the module name "archinfo" is fine, but each separate thing
> > it shows should get its own file.  Starting with:
> > 
> >     /sys/kernel/debug/x86/gdtinfo
> > 
> > for the current output?
> 
> Right, or put everything under a directory "archinfo":
> 
> /sys/kernel/debug/x86/archinfo/ ... gdt
> 				... msrs
> 
> 				...
> 
> and so on.
> 
> Yap, sounds better. Thanks!

Agreed. We used to have something like this but then removed it due to various 
problems - but the concept itself is fine.

Note that these can be pretty security sensitive pieces of information, and can 
also expose ASLR/KASLR details, so the VFS interface needs to be a strictly 
root-only thing.

Thanks,

	Ingo