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c=simple/simple; d=arm.com; s=foss; t=1789661161; bh=9mcxnDc8qxIpxmpk6T3Tp+BnQwg+ATLN/zS0rC02bj4=; h=Date:From:To:Cc:Subject:References:In-Reply-To:From; b=iSTmFOj/SjkZUclQCqE4zTW0vk94VTD2VbErQFckNg1Hf9DqR+Wb+AcjT1kbXrZTY 9NCVL8hRLjredBc9QRerBZnnZDifRLrHjsitRjiaswGzll4lpHF3AB6KbXTdEHKJsU MLwoOZ4/t3+aNJhsyRfmX7PHIpukuOpzzytXFkiM= Date: Thu, 17 Sep 2026 17:05:53 +0100 From: Catalin Marinas To: "Aneesh Kumar K.V (Arm)" Cc: iommu@lists.linux.dev, linux-kernel@vger.kernel.org, Robin Murphy , Marek Szyprowski , Will Deacon , Marc Zyngier , Steven Price , Suzuki K Poulose , Jiri Pirko , Jason Gunthorpe , Mostafa Saleh , Petr Tesarik , Alexey Kardashevskiy , Dan Williams , Xu Yilun , Madhavan Srinivasan , Michael Ellerman , Nicholas Piggin , "Christophe Leroy (CS GROUP)" , Alexander Gordeev , Gerald Schaefer , Heiko Carstens , Vasily Gorbik , Christian Borntraeger , Sven Schnelle , Russell King , Huacai Chen , Thomas Bogendoerfer , Jiaxun Yang , Paul Walmsley , Palmer Dabbelt , Albert Ou , Thomas Gleixner , Ingo Molnar , Borislav Petkov , Dave Hansen , linux-arm-kernel@lists.infradead.org, loongarch@lists.linux.dev, linux-mips@vger.kernel.org, linuxppc-dev@lists.ozlabs.org, linux-riscv@lists.infradead.org, linux-s390@vger.kernel.org, x86@kernel.org Subject: Re: [PATCH v4 4/5] dma: swiotlb: Add an overridable architecture pool opt-out Message-ID: References: <20260914070135.313337-1-aneesh.kumar@kernel.org> <20260914070135.313337-5-aneesh.kumar@kernel.org> X-Mailing-List: linuxppc-dev@lists.ozlabs.org List-Id: List-Help: List-Owner: List-Post: List-Archive: , List-Subscribe: , , List-Unsubscribe: Precedence: list MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <20260914070135.313337-5-aneesh.kumar@kernel.org> On Mon, Sep 14, 2026 at 12:31:33PM +0530, Aneesh Kumar K.V (Arm) wrote: > diff --git a/include/linux/swiotlb.h b/include/linux/swiotlb.h > index be3962a33fc6..ef7a776ee508 100644 > --- a/include/linux/swiotlb.h > +++ b/include/linux/swiotlb.h > @@ -20,6 +20,8 @@ struct scatterlist; > #define SWIOTLB_INIT_ADDRESSING_LIMIT (1 << 2) > /* Initialize a default-sized pool that requires architecture remapping. */ > #define SWIOTLB_INIT_REMAP (1 << 3) > +/* Do not initialize a pool unless SWIOTLB is explicitly required. */ > +#define SWIOTLB_INIT_FORCE_DISABLE (1 << 4) Nit: maybe better as SWIOTLB_INIT_DEFAULT_OFF. "Force" sounds too drastic and it can be overridden on the command line to re-enable. Reviewed-by: Catalin Marinas