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Date: Fri, 22 Mar 2013 20:37:01 +0530
From: Ananth N Mavinakayanahalli <ananth@in.ibm.com>
To: Oleg Nesterov <oleg@redhat.com>
Subject: Re: [PATCH 1/3] uprobes: add trap variant helper
Message-ID: <20130322150701.GA20010@in.ibm.com>
References: <20130322114446.GG26183@in.ibm.com>
 <20130322145406.GB17286@redhat.com>
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On Fri, Mar 22, 2013 at 03:54:06PM +0100, Oleg Nesterov wrote:
> On 03/22, Ananth N Mavinakayanahalli wrote:
> >
> > +/**
> > + * is_trap_insn - check if instruction is breakpoint instruction.
> > + * @insn: instruction to be checked.
> > + * Default implementation of is_trap_insn
> > + * Returns true if @insn is a breakpoint instruction.
> > + *
> > + * This function is needed for the case where an architecture has multiple
> > + * trap instructions (like powerpc).
> > + */
> > +bool __weak is_trap_insn(uprobe_opcode_t *insn)
> > +{
> > +	return is_swbp_insn(insn);
> > +}
> 
> OK, thanks, the whole series looks fine, just one note...

OK.

> My patch also changed prepare_uprobe() to use is_trap_insn(), and I think
> this is right. Exactly because of 3/3 which removes is_trap() from
> arch_uprobe_analyze_insn().
> 
> If the original insn is_trap(), we do not want to singlestep it and get
> another trap after we hit handle_swbp().

OK, I'll send a v2 with that change.

Ananth