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Date: Fri, 10 Oct 2025 11:40:38 +0100
From: Catalin Marinas <catalin.marinas@arm.com>
To: Marek Szyprowski <m.szyprowski@samsung.com>
Cc: iommu@lists.linux.dev, linux-kernel@vger.kernel.org,
	Robin Murphy <robin.murphy@arm.com>, Christoph Hellwig <hch@lst.de>,
	Andrew Morton <akpm@linux-foundation.org>
Subject: Re: [PATCH] dma-debug: don't report false positives with
 DMA_BOUNCE_UNALIGNED_KMALLOC
Message-ID: <aOjipm1vCJpgQQq1@arm.com>
References: <CGME20251009141522eucas1p2c89eadd93fb571c557d3d70975d8ae4f@eucas1p2.samsung.com>
 <20251009141508.2342138-1-m.szyprowski@samsung.com>
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In-Reply-To: <20251009141508.2342138-1-m.szyprowski@samsung.com>

On Thu, Oct 09, 2025 at 04:15:08PM +0200, Marek Szyprowski wrote:
> @@ -594,7 +595,9 @@ static void add_dma_entry(struct dma_debug_entry *entry, unsigned long attrs)
>  	if (rc == -ENOMEM) {
>  		pr_err_once("cacheline tracking ENOMEM, dma-debug disabled\n");
>  		global_disable = true;
> -	} else if (rc == -EEXIST && !(attrs & DMA_ATTR_SKIP_CPU_SYNC)) {
> +	} else if (rc == -EEXIST && !(attrs & DMA_ATTR_SKIP_CPU_SYNC) &&
> +		   !(IS_ENABLED(CONFIG_DMA_BOUNCE_UNALIGNED_KMALLOC) &&
> +		     is_swiotlb_allocated())) {

Maybe use is_swiotlb_active(entry->dev) instead for completeness. Either
way:

Reviewed-by: Catalin Marinas <catalin.marinas@arm.com>