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Date: Tue, 9 Dec 2014 21:10:20 +0100 (CET)
From: Thomas Gleixner <tglx@linutronix.de>
To: Pranith Kumar <bobby.prani@gmail.com>
cc: Ingo Molnar <mingo@redhat.com>, "H. Peter Anvin" <hpa@zytor.com>,
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        Dave Hansen <dave.hansen@linux.intel.com>,
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Subject: Re: [RFC PATCH] smpboot: Check for successfull allocation of cpumask
 vars
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On Tue, 9 Dec 2014, Pranith Kumar wrote:
> zalloc_cpumask_var() can return 0 on allocation failure when
> CONFIG_CPUMASK_OFFSTACK is set. Check for the return value and WARN() on failure
> of an allocation in such cases.

And that warning helps in which way?

It just prints a completely useless backtrace and breaks out of the
loop, but it does not prevent that later on code will trip over the
non allocated per cpu data.

Thanks,

	tglx