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Date:   Fri, 7 Oct 2022 18:43:56 +0200
From:   Greg KH <greg@kroah.com>
To:     Jiaxun Yang <jiaxun.yang@flygoat.com>
Cc:     "linux-mips@vger.kernel.org" <linux-mips@vger.kernel.org>,
        linux-kernel@vger.kernel.org,
        Thomas Bogendoerfer <tsbogend@alpha.franken.de>,
        linux-api@vger.kernel.org, f.fainelli@gmail.com
Subject: Re: [PATCH v5] MIPS: Expose prid and globalnumber to sysfs
Message-ID: <Y0BXTP4ur6bxrpim@kroah.com>
References: <20221007141207.30635-1-jiaxun.yang@flygoat.com>
 <Y0A9L2KajswAEKsu@kroah.com>
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On Fri, Oct 07, 2022 at 05:37:34PM +0100, Jiaxun Yang wrote:
> 
> 
> 在2022年10月7日十月 下午3:52，Greg KH写道：
> [...]
> >> +
> >> +static int cpuregs_cpu_offline(unsigned int cpu)
> >> +{
> >> +	struct device *dev;
> >> +	struct cpureg *reg = per_cpu(cpuregs, cpu);
> >> +
> >> +	dev = get_cpu_device(cpu);
> >> +	if (!dev || !reg)
> >> +		return -ENODEV;
> >> +	if (reg->kobj.parent) {
> >
> > Why are you looking at the parent of a kobject?  Why not just always
> > remove the kobject if you have a reference to it now?  How does the
> > parent matter?
> 
> Another dummy copy from Arm64 code... kobject_put should be enough here?

Why would it not be enough?