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Date: Tue, 9 May 2017 22:41:27 +0200 (CEST)
From: Thomas Gleixner <tglx@linutronix.de>
To: Andy Lutomirski <luto@kernel.org>
cc: X86 ML <x86@kernel.org>,
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        Nadav Amit <namit@vmware.com>, Michal Hocko <mhocko@suse.com>,
        Arjan van de Ven <arjan@linux.intel.com>
Subject: Re: [RFC 09/10] x86/mm: Rework lazy TLB to track the actual loaded
 mm
In-Reply-To: <1a124281c99741606f1789140f9805beebb119da.1494160201.git.luto@kernel.org>
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References: <cover.1494160201.git.luto@kernel.org> <1a124281c99741606f1789140f9805beebb119da.1494160201.git.luto@kernel.org>
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On Sun, 7 May 2017, Andy Lutomirski wrote:
>  /* context.lock is held for us, so we don't need any locking. */
>  static void flush_ldt(void *current_mm)
>  {
> +	struct mm_struct *mm = current_mm;
>  	mm_context_t *pc;
>  
> -	if (current->active_mm != current_mm)
> +	if (this_cpu_read(cpu_tlbstate.loaded_mm) != current_mm)

While functional correct, this really should compare against 'mm'.

>  		return;
>  
> -	pc = &current->active_mm->context;
> +	pc = &mm->context;

Thanks,

	tglx