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Date: Mon, 05 May 2014 19:32:32 +0200
From: Denys Vlasenko <dvlasenk@redhat.com>
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To: Oleg Nesterov <oleg@redhat.com>
CC: linux-kernel@vger.kernel.org, Jim Keniston <jkenisto@us.ibm.com>,
        Masami Hiramatsu <masami.hiramatsu.pt@hitachi.com>,
        Srikar Dronamraju <srikar@linux.vnet.ibm.com>,
        Ingo Molnar <mingo@kernel.org>
Subject: Re: [PATCH v2] uprobes: fix scratch register selection for rip-relative
 fixups
References: <1399043040-28366-1-git-send-email-dvlasenk@redhat.com> <20140505154559.GA27072@redhat.com>
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On 05/05/2014 05:45 PM, Oleg Nesterov wrote:
> On 05/02, Denys Vlasenko wrote:
>>  static inline unsigned long *
>>  scratch_reg(struct arch_uprobe *auprobe, struct pt_regs *regs)
>>  {
>> -	return (auprobe->def.fixups & UPROBE_FIX_RIP_AX) ? &regs->ax : &regs->cx;
>> +	/* Order is important - more than one bit can be set! */
> 
> Really?
> 
> Should I remove this comment or I misread the change in riprel_analyze?

Yes, it is not true: latest code sets only one bit.