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Date: Mon, 21 Sep 2026 13:50:10 +0100
From: Catalin Marinas <catalin.marinas@arm.com>
To: "Aneesh Kumar K.V (Arm)" <aneesh.kumar@kernel.org>
Cc: iommu@lists.linux.dev, linux-kernel@vger.kernel.org,
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Subject: Re: [PATCH v5 2/6] dma: swiotlb: Track whether the pool size was
 explicitly set
Message-ID: <arEoAq9mhsx2mt1P@arm.com>
References: <20260921063628.362078-1-aneesh.kumar@kernel.org>
 <20260921063628.362078-3-aneesh.kumar@kernel.org>
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In-Reply-To: <20260921063628.362078-3-aneesh.kumar@kernel.org>

On Mon, Sep 21, 2026 at 12:06:24PM +0530, Aneesh Kumar K.V (Arm) wrote:
> swiotlb_adjust_size() must not override a pool size supplied through the
> swiotlb= command-line parameter.
> 
> Currently, it determines whether a size was supplied by comparing
> default_nslabs with IO_TLB_DEFAULT_SIZE. This fails when the user
> explicitly requests the compiled-in default size, allowing the request
> to be overwritten by automatic pool sizing.
> 
> Record whether swiotlb= supplied a numeric size and add
> swiotlb_default_size_changed() to query that state.
> 
> Signed-off-by: Aneesh Kumar K.V (Arm) <aneesh.kumar@kernel.org>

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