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Subject: Re: [PATCH v3 2.6.39-rc1-tip 7/26]  7: x86: analyze instruction and determine fixups.
From: Peter Zijlstra <peterz@infradead.org>
To: Srikar Dronamraju <srikar@linux.vnet.ibm.com>
Cc: Steven Rostedt <rostedt@goodmis.org>, Ingo Molnar <mingo@elte.hu>, Linux-mm <linux-mm@kvack.org>, Arnaldo Carvalho de Melo <acme@infradead.org>, Linus Torvalds <torvalds@linux-foundation.org>, Andi Kleen <andi@firstfloor.org>, Christoph Hellwig <hch@infradead.org>, Jonathan Corbet <corbet@lwn.net>, Thomas Gleixner <tglx@linutronix.de>, Masami Hiramatsu <masami.hiramatsu.pt@hitachi.com>,  Oleg Nesterov <oleg@redhat.com>, LKML <linux-kernel@vger.kernel.org>, SystemTap <systemtap@sources.redhat.com>,  Jim Keniston <jkenisto@linux.vnet.ibm.com>, Roland McGrath <roland@hack.frob.com>, Ananth N Mavinakayanahalli <ananth@in.ibm.com>, Andrew Morton <akpm@linux-foundation.org>
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On Thu, 2011-04-21 at 23:01 +0530, Srikar Dronamraju wrote:
> 
> Sometimes, the user might try registering a probe at a valid file +
> valid offset + valid consumer; but an instruction that we cant probe.
> Then trying to figure why its failing would be very hard. 

Uhm, how about failing to create the probe to begin with?

You can even do that in userspace as you can inspect the DSO you're
going to probe (and pretty much have to, since you'll have to pass the
kernel a fd to hand it the proper inode).