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Subject: Re: [RFC V3] mm: Generalize and rename notify_page_fault() as
 kprobe_page_fault()
To:     Stephen Rothwell <sfr@canb.auug.org.au>
Cc:     linux-kernel@vger.kernel.org, linux-mm@kvack.org,
        linux-arm-kernel@lists.infradead.org, linux-ia64@vger.kernel.org,
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        Catalin Marinas <catalin.marinas@arm.com>,
        Will Deacon <will.deacon@arm.com>,
        Tony Luck <tony.luck@intel.com>,
        Fenghua Yu <fenghua.yu@intel.com>,
        Martin Schwidefsky <schwidefsky@de.ibm.com>,
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        "David S. Miller" <davem@davemloft.net>,
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References: <1559903655-5609-1-git-send-email-anshuman.khandual@arm.com>
 <20190607220326.1e21fc9c@canb.auug.org.au>
From:   Anshuman Khandual <anshuman.khandual@arm.com>
Message-ID: <632eae55-92f5-1bfc-bfe4-24673558e1d8@arm.com>
Date:   Mon, 10 Jun 2019 07:53:15 +0530
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On 06/07/2019 05:33 PM, Stephen Rothwell wrote:
> Hi Anshuman,
> 
> On Fri,  7 Jun 2019 16:04:15 +0530 Anshuman Khandual <anshuman.khandual@arm.com> wrote:
>>
>> +static nokprobe_inline bool kprobe_page_fault(struct pt_regs *regs,
>> +					      unsigned int trap)
>> +{
>> +	int ret = 0;
>> +
>> +	/*
>> +	 * To be potentially processing a kprobe fault and to be allowed
>> +	 * to call kprobe_running(), we have to be non-preemptible.
>> +	 */
>> +	if (kprobes_built_in() && !preemptible() && !user_mode(regs)) {
>> +		if (kprobe_running() && kprobe_fault_handler(regs, trap))
>> +			ret = 1;
>> +	}
>> +	return ret;
>> +}
> 
> Since this is now declared as "bool" (thanks for that), you should make
> "ret" be bool and use true and false;

Sure, done.