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Subject: Re: [RFC] [PATCH 2.6.37-rc5-tip 5/20]  5: Uprobes:
 register/unregister probes.
From: Peter Zijlstra <peterz@infradead.org>
To: Srikar Dronamraju <srikar@linux.vnet.ibm.com>
Cc: Ingo Molnar <mingo@elte.hu>, Steven Rostedt <rostedt@goodmis.org>,
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Date: Thu, 27 Jan 2011 11:41:17 +0100
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On Thu, 2011-01-27 at 15:55 +0530, Srikar Dronamraju wrote:
> 
> 
> If its not at the exact same location, then our third validation of
> checking that (vaddr == vma->vm_start + uprobe->offset)  should fail
> right?
> 
> Also should it be (vaddr == uprobe->offset + vma->vm_start -
> vma->pgoff << PAGE_SHIFT) ?

Yeah, although I just realized that ->offset should be a u64, since
pgoff is a unsigned long, we can have files up to 44 bit (assuming the
page-size is 12bits).

But yes, this matches the validation I mentioned.