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Date: Wed, 6 Jun 2012 17:14:23 +0530
From: Srikar Dronamraju <srikar@linux.vnet.ibm.com>
To: Ingo Molnar <mingo@kernel.org>
Subject: Re: [PATCH 1/2] uprobes: Pass probed vaddr to
 arch_uprobe_analyze_insn()
Message-ID: <20120606114423.GA32094@linux.vnet.ibm.com>
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Cc: Peter Zijlstra <peterz@infradead.org>, lkml <linux-kernel@vger.kernel.org>,
 oleg@redhat.com, Paul Mackerras <paulus@samba.org>,
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* Ingo Molnar <mingo@kernel.org> [2012-06-06 11:40:15]:

> 
> * Ananth N Mavinakayanahalli <ananth@in.ibm.com> wrote:
> 
> > On Wed, Jun 06, 2012 at 11:23:52AM +0200, Peter Zijlstra wrote:
> > > On Wed, 2012-06-06 at 14:49 +0530, Ananth N Mavinakayanahalli wrote:
> > > > +int arch_uprobe_analyze_insn(struct arch_uprobe *auprobe, struct mm_struct *mm, loff_t vaddr)
> > > 
> > > Don't we traditionally use unsigned long to pass vaddrs?
> > 
> > Right. But the vaddr we pass here is vma_info->vaddr which is loff_t.
> > I guess I should've made that clear in the patch description.
> 
> Why not fix struct vma_info's vaddr type?
> 

Calculating and comparing vaddr results either uses variables of type loff_t. 
To avoid typecasting and avoid overflow at each of these places, we used
loff_t. 

Ananth, install_breakpoint() already has a variable of type addr of type
unsigned long.  Why dont you use addr instead of vaddr. 

-- 
Thanks and regards
Srikar