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Date:   Mon, 14 Feb 2022 13:41:27 +0100
From:   Joerg Roedel <joro@8bytes.org>
To:     Robin Murphy <robin.murphy@arm.com>
Cc:     Jiasheng Jiang <jiasheng@iscas.ac.cn>, will@kernel.org,
        iommu@lists.linux-foundation.org, linux-kernel@vger.kernel.org,
        Nikita Yushchenko <nikita.yoush@cogentembedded.com>,
        Laurent Pinchart <laurent.pinchart+renesas@ideasonboard.com>
Subject: Re: [PATCH] iommu/ipmmu-vmsa: Check for error num after setting mask
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References: <20220106024302.2574180-1-jiasheng@iscas.ac.cn>
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On Mon, Feb 14, 2022 at 12:32:21PM +0000, Robin Murphy wrote:
> In this particular case it cannot fail on any system the driver actually
> runs on - it's a platform device so the dma_mask pointer is always
> initialised, then dma_direct_supported() on arm64 will always return true
> for any mask wider than 32 bits, while arm_dma_supported() will also always
> pass since a 32-bit system cannot have memory above 40 bits either.
> 
> There's no great harm in adding the check for the sake of consistency, I
> guess, but it's purely cosmetic and not fixing anything.

Okay, thanks Robin and Nikita for looking to quickly into this. I will
apply it for 5.18 just to be on the safe side if the above assumptions
change.

Regards,

	Joerg