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Date:   Fri, 4 Oct 2019 19:45:53 +0200
From:   Sebastian Andrzej Siewior <bigeasy@linutronix.de>
To:     Uladzislau Rezki <urezki@gmail.com>
Cc:     Daniel Wagner <dwagner@suse.de>, linux-mm@kvack.org,
        linux-kernel@vger.kernel.org, linux-rt-users@vger.kernel.org,
        Andrew Morton <akpm@linux-foundation.org>
Subject: Re: [PATCH] mm: vmalloc: Use the vmap_area_lock to protect
 ne_fit_preload_node
Message-ID: <20191004174553.5fk2amnp4jblc7cy@linutronix.de>
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On 2019-10-04 19:04:11 [+0200], Uladzislau Rezki wrote:
> if another, we can free the object allocated on previous step if
> it already has it. If another CPU does not have it, save it in 
> ne_fit_preload_node for another current CPU to reuse later. Further
> we can not migrate because of:
> 
> <snip>
>     spin_lock(&vmap_area_lock);
>     preempt_enable();
> <snip>

ah right. So you keep the lock later on, I somehow missed that part.
That way it actually makes sense.

Sebastian