Message-ID: <1353426955.6276.24.camel@gandalf.local.home>
Subject: Re: [PATCH] arch_check_bp_in_kernelspace: fix the range check
From: Steven Rostedt <rostedt@goodmis.org>
To: Oleg Nesterov <oleg@redhat.com>
Cc: Frederic Weisbecker <fweisbec@gmail.com>, Ingo Molnar <mingo@redhat.com>,
        Peter Zijlstra <a.p.zijlstra@chello.nl>,
        Amnon Shiloh <u3557@miso.sublimeip.com>, linux-kernel@vger.kernel.org
Date: Tue, 20 Nov 2012 10:55:55 -0500
In-Reply-To: <20121120154824.GA17534@redhat.com>
References: <20121109182943.GA2789@redhat.com>
	 <20121109183026.GA2719@redhat.com> <20121119174728.GA11365@redhat.com>
	 <1353349500.6276.9.camel@gandalf.local.home>
	 <20121120154824.GA17534@redhat.com>
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On Tue, 2012-11-20 at 16:48 +0100, Oleg Nesterov wrote:

> > But here, there's no prejudice between tasks. All tasks will now hit the
> > breakpoint regardless of if it is being traced or not.
>   ^^^^^^^^^^
> 
> This is hardware breakpoint, it is per-task.

I forgot that hw breakpoints are swapped out at context switch (as Amnon
informed me). 

OK, that makes a big difference.

Thanks,

-- Steve


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