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Re: [PATCH v3 2.6.39-rc1-tip 15/26] 15: uprobes: Handing int3 and singlestep exception.
- From: Steven Rostedt <rostedt at goodmis dot org>
- To: Peter Zijlstra <peterz at infradead dot org>
- Cc: Srikar Dronamraju <srikar at linux dot vnet dot ibm dot com>, Ingo Molnar <mingo at elte dot hu>, Linux-mm <linux-mm at kvack dot org>, Arnaldo Carvalho de Melo <acme at infradead dot org>, Linus Torvalds <torvalds at linux-foundation dot org>, Jonathan Corbet <corbet at lwn dot net>, Christoph Hellwig <hch at infradead dot org>, Masami Hiramatsu <masami dot hiramatsu dot pt at hitachi dot com>, Thomas Gleixner <tglx at linutronix dot de>, Ananth N Mavinakayanahalli <ananth at in dot ibm dot com>, Oleg Nesterov <oleg at redhat dot com>, LKML <linux-kernel at vger dot kernel dot org>, SystemTap <systemtap at sources dot redhat dot com>, Jim Keniston <jkenisto at linux dot vnet dot ibm dot com>, Roland McGrath <roland at hack dot frob dot com>, Andi Kleen <andi at firstfloor dot org>, Andrew Morton <akpm at linux-foundation dot org>
- Date: Tue, 19 Apr 2011 09:12:21 -0400
- Subject: Re: [PATCH v3 2.6.39-rc1-tip 15/26] 15: uprobes: Handing int3 and singlestep exception.
- References: <20110401143223.15455.19844.sendpatchset@localhost6.localdomain6> <20110401143527.15455.32854.sendpatchset@localhost6.localdomain6> <1303218185.8345.0.camel@twins>
On Tue, 2011-04-19 at 15:03 +0200, Peter Zijlstra wrote:
> On Fri, 2011-04-01 at 20:05 +0530, Srikar Dronamraju wrote:
> > + if (unlikely(!utask)) {
> > + utask = add_utask();
> > +
> > + /* Failed to allocate utask for the current task. */
> > + BUG_ON(!utask);
>
> That's not really nice is it ;-) means I can make the kernel go BUG by
> simply applying memory pressure.
Agreed,
None of these patches should have a single BUG_ON(). They all must fail
nicely.
-- Steve
>
> > + utask->state = UTASK_BP_HIT;
> > + }