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Subject: Re: [PATCH v2 7/11] Uprobes Implementation
From: Peter Zijlstra <peterz@infradead.org>
To: "Frank Ch. Eigler" <fche@redhat.com>
Cc: Oleg Nesterov <oleg@redhat.com>,
       Srikar Dronamraju <srikar@linux.vnet.ibm.com>,
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Date: Tue, 11 May 2010 23:01:44 +0200
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On Tue, 2010-05-11 at 16:57 -0400, Frank Ch. Eigler wrote:
> Hi -
> 
> On Tue, May 11, 2010 at 10:32:18PM +0200, Peter Zijlstra wrote:
> > [...]
> > Right so what I've suggested several times it to simply call the same
> > handler in both contexts. If it returns -EFAULT, set TIF_UPROBE or
> > whatever and try again from task context.
> 
> That could work, but random partial execution & restart of the handler
> will make it tricky to write a single handler that reliably produces
> results.  It would likely need a flag to indicate that it failed
> previously so as to throw away partial results.

Or it shouldn't leave half-assed state around to begin with.