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Date: Fri, 24 Nov 2017 14:43:40 +0100
From: Peter Zijlstra <peterz@infradead.org>
To: Ingo Molnar <mingo@kernel.org>
Cc: linux-kernel@vger.kernel.org,
        Dave Hansen <dave.hansen@linux.intel.com>,
        Andy Lutomirski <luto@amacapital.net>,
        Thomas Gleixner <tglx@linutronix.de>,
        "H . Peter Anvin" <hpa@zytor.com>, Borislav Petkov <bp@alien8.de>,
        Linus Torvalds <torvalds@linux-foundation.org>
Subject: Re: [PATCH 28/43] x86/mm/kaiser: Map CPU entry area
Message-ID: <20171124134340.u4ulw6tjigdmemmi@hirez.programming.kicks-ass.net>
References: <20171124091448.7649-1-mingo@kernel.org>
 <20171124091448.7649-29-mingo@kernel.org>
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On Fri, Nov 24, 2017 at 10:14:33AM +0100, Ingo Molnar wrote:
> + 	/* CPU 0's mapping is done in kaiser_init() */
> +	if (cpu)
> +		kaiser_add_mapping_cpu_entry(cpu);

This hard assumes CPU0 is the boot CPU. I know we dropped Voyager
support a while back, but can/should we hard rely on that?

We do have __boot_cpu_id / get_boot_cpu_id() for these here things.