Date: Thu, 17 Mar 2016 12:57:04 +0100
From: Borislav Petkov <bp@alien8.de>
To: Peter Zijlstra <peterz@infradead.org>
Cc: Thomas Gleixner <tglx@linutronix.de>, Xiong Zhou <jencce.kernel@gmail.com>,
        "linux-kernel@vger.kernel.org" <linux-kernel@vger.kernel.org>,
        Ingo Molnar <mingo@kernel.org>, Andreas Herrmann <aherrmann@suse.com>,
        Jens Axboe <axboe@kernel.dk>
Subject: Re: 4.5.0+ panic when setup loop device
Message-ID: <20160317115704.GD28772@pd.tnic>
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On Thu, Mar 17, 2016 at 12:51:20PM +0100, Peter Zijlstra wrote:
> On Thu, Mar 17, 2016 at 12:39:46PM +0100, Thomas Gleixner wrote:
> > But we have to clarify and document whether holes in cpu_possible_mask are not
> > allowed at all or if code like the above is simply broken.
> 
> So the general rule is that cpumasks can have holes, and exempting one
> just muddles the water.
> 
> Therefore I'd call the code just plain broken.

I'll say.

Can't the code simply do:

	if (!cpu_possible(i))
		continue;

?

-- 
Regards/Gruss,
    Boris.

ECO tip #101: Trim your mails when you reply.