Re: [PATCH v3 06/11] x86/mm: Rework lazy TLB mode and TLB freshness tracking

[Boris Ostrovsky]

> diff --git a/arch/x86/xen/mmu_pv.c b/arch/x86/xen/mmu_pv.c
> index 1d7a7213a310..f5df56fb8b5c 100644
> --- a/arch/x86/xen/mmu_pv.c
> +++ b/arch/x86/xen/mmu_pv.c
> @@ -1005,8 +1005,7 @@ static void xen_drop_mm_ref(struct mm_struct *mm)
>   	/* Get the "official" set of cpus referring to our pagetable. */
>   	if (!alloc_cpumask_var(&mask, GFP_ATOMIC)) {
>   		for_each_online_cpu(cpu) {
> -			if (!cpumask_test_cpu(cpu, mm_cpumask(mm))
> -			    && per_cpu(xen_current_cr3, cpu) != __pa(mm->pgd))
> +			if (per_cpu(xen_current_cr3, cpu) != __pa(mm->pgd))
>   				continue;
>   			smp_call_function_single(cpu, drop_mm_ref_this_cpu, mm, 1);
>   		}


I wonder then whether
	cpumask_copy(mask, mm_cpumask(mm));
immediately below is needed.

-boris