From: Nadav Amit <namit@vmware.com>
To: Sergey Senozhatsky <sergey.senozhatsky@gmail.com>,
        Minchan Kim <minchan@kernel.org>
CC: Mel Gorman <mgorman@suse.de>, Rik van Riel <riel@redhat.com>,
        "Andy Lutomirski" <luto@kernel.org>,
        Andrew Morton <akpm@linux-foundation.org>,
        Michal Hocko <mhocko@kernel.org>, LKML <linux-kernel@vger.kernel.org>
Subject: Re: [mmots] build error: mm: prevent racy access to tlb_flush_pending
Thread-Topic: [mmots] build error: mm: prevent racy access to
 tlb_flush_pending
Thread-Index: AQHTBtTGdU6D3+FhQES4ULpORCsjw6JnyWqA
Date: Thu, 27 Jul 2017 15:18:02 +0000
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Sergey Senozhatsky <sergey.senozhatsky@gmail.com> wrote:

> Hello,
> 
> 8c636138f497b36ae95f ("mm: prevent racy access to tlb_flush_pending") kills
> the build
> 
> kernel/fork.c: In function ‘mm_init’:
> kernel/fork.c:810:18: error: ‘struct mm_struct’ has no member named ‘tlb_flush_pending’; did you mean ‘tlb_flush_batched’?
>  atomic_set(&mm->tlb_flush_pending, 0);
>                  ^~~~~~~~~~~~~~~~~
>                  tlb_flush_batched
> 
> 
> 
> replacing clear_tlb_flush_pending() with a direct ->tlb_flush_pending
> access
> 
> @@ -807,7 +807,7 @@ static struct mm_struct *mm_init(struct mm_struct *mm, struct task_struct *p,
>        mm_init_aio(mm);
>        mm_init_owner(mm, p);
>        mmu_notifier_mm_init(mm);
> -       clear_tlb_flush_pending(mm);
> +       atomic_set(&mm->tlb_flush_pending, 0);
> 
> 
> doesn't work on on !CONFIG_NUMA_BALANCING && !CONFIG_COMPACTION systems.
> 
> 	-ss

Missed this one. Thanks, I will fix it for v3.

When Minchan repurpose this field, he should remove all of these defines
(including those in mm_types.h).

Minchan, do you want me to do it?

Nadav