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Date: Mon, 24 Nov 2025 17:03:42 +0000
From: Will Deacon <will@kernel.org>
To: Aashish Sharma <aashish@aashishsharma.net>
Cc: Vineeth Pillai <vineeth@bitbyteword.org>,
	Dmytro Maluka <dmaluka@google.com>, Joerg Roedel <joro@8bytes.org>,
	Robin Murphy <robin.murphy@arm.com>, iommu@lists.linux.dev,
	linux-kernel@vger.kernel.org, Aashish Sharma <shraash@google.com>
Subject: Re: [PATCH] iommu: Remove redundant null check in
 iommu_iotlb_gather_queued
Message-ID: <aSSP7sG0OMFGElS9@willie-the-truck>
References: <20251111051952.1985154-1-aashish@aashishsharma.net>
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In-Reply-To: <20251111051952.1985154-1-aashish@aashishsharma.net>

On Mon, Nov 10, 2025 at 09:19:52PM -0800, Aashish Sharma wrote:
> The callers of 'iommu_iotlb_gather_queued' always have a non-null
> 'gather', so we don't need to check for the same in the function.

That's not obviously true to me, how did you check it?

For example, msm_iommu_pagetable_unmap() appears to call into
io_pgtable_ops::unmap_pages() with a NULL gather pointer.

Will