Received-SPF: pass (google.com: domain of linux-kernel-owner@vger.kernel.org designates 23.128.96.18 as permitted sender) client-ip=23.128.96.18;
MIME-Version: 1.0
References: <20210629130048.820142-1-glider@google.com>
In-Reply-To: <20210629130048.820142-1-glider@google.com>
From:   Marco Elver <elver@google.com>
Date:   Tue, 29 Jun 2021 15:05:00 +0200
Message-ID: <CANpmjNN35j2Sf17TMqpOVZZv2N6ELzBZOsG5-jpFoPvgfuVzFA@mail.gmail.com>
Subject: Re: [PATCH] kfence: skip DMA allocations
To:     Alexander Potapenko <glider@google.com>
Cc:     akpm@linux-foundation.org, dvyukov@google.com,
        linux-kernel@vger.kernel.org, linux-mm@kvack.org,
        stable@vger.kernel.org
Content-Type: text/plain; charset="UTF-8"
Precedence: bulk

On Tue, 29 Jun 2021 at 15:00, Alexander Potapenko <glider@google.com> wrote:
[...]
> +       /*
> +        * Skip DMA allocations. These must reside in the low memory, which we
> +        * cannot guarantee.
> +        */
> +       if (flags & (__GFP_DMA | __GFP_DMA32) ||

I think we want braces around "flags & (...)", so that this becomes:

    if ((flags & (...)) ||

> +           (s->flags & (SLAB_CACHE_DMA | SLAB_CACHE_DMA32)))
> +               return NULL;

Thanks,
-- Marco