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Date: Mon, 27 May 2024 21:49:07 -0700
From: Christoph Hellwig <hch@infradead.org>
To: Andy Shevchenko <andriy.shevchenko@linux.intel.com>
Cc: iommu@lists.linux.dev, linux-kernel@vger.kernel.org,
	Robin Murphy <robin.murphy@arm.com>, Joerg Roedel <joro@8bytes.org>,
	Will Deacon <will@kernel.org>,
	=?iso-8859-1?Q?N=EDcolas_F_=2E_R_=2E_A_=2E?= Prado <nfraprado@collabora.com>
Subject: Re: [PATCH v1 1/1] iommu/dma: Make SG mapping and syncing robust
 against empty tables
Message-ID: <ZlViQ8jLOp-9l9BN@infradead.org>
References: <20240527232625.462045-1-andriy.shevchenko@linux.intel.com>
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In-Reply-To: <20240527232625.462045-1-andriy.shevchenko@linux.intel.com>

On Tue, May 28, 2024 at 02:26:25AM +0300, Andy Shevchenko wrote:
> Statistically there are only a few cases in the kernel that do such a
> check. However, any attempt to make it alinged with the rest 99%+ cases
> will be a regression due to above mentioned relatively recent change.
> Instead of asking a caller to perform the checks, just return status quo
> to SG mapping and syncing callbacks, so they won't crash on
> uninitialised SG list.

This is not a valid use of the API, please fix the callers instead.