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Date:   Sat, 16 Nov 2019 17:29:37 +0100
From:   Christoph Hellwig <hch@lst.de>
To:     Andy Shevchenko <andriy.shevchenko@linux.intel.com>
Cc:     linux-kernel@vger.kernel.org, Christoph Hellwig <hch@lst.de>,
        Dan Williams <dan.j.williams@intel.com>,
        Arnd Bergmann <arnd@arndb.de>,
        Marek Szyprowski <m.szyprowski@samsung.com>,
        Robin Murphy <robin.murphy@arm.com>,
        Jaroslav Kysela <perex@perex.cz>,
        Takashi Iwai <tiwai@suse.com>,
        Pierre-Louis Bossart <pierre-louis.bossart@linux.intel.com>,
        Ard Biesheuvel <ardb@kernel.org>,
        Alex Williamson <alex.williamson@redhat.com>,
        Cornelia Huck <cohuck@redhat.com>
Subject: Re: [PATCH v1 1/5] memremap: Check for size parameter
Message-ID: <20191116162937.GA23951@lst.de>
References: <20191115180044.83659-1-andriy.shevchenko@linux.intel.com>
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On Fri, Nov 15, 2019 at 08:00:40PM +0200, Andy Shevchenko wrote:
> There is no use of memremap() to be called with size = 0.
> Simple return NULL pointer and allow callers to drop this check.

Given that this really is an error condition, maybe a WARN_ON_ONCE
would fit here?