From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from foss.arm.com (foss.arm.com [217.140.110.172]) by smtp.subspace.kernel.org (Postfix) with ESMTP id BB6164E4C35; Thu, 17 Sep 2026 16:06:01 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.client-ip=217.140.110.172 ARC-Seal:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1789661164; cv=none; b=qGpN5z0A6QfkYKkti/tpUNJ+GjvXYX3EdmiECfVMQ91y8X089a7ntlagjCHzg8ucxKJquLqeXmltRhRrUqNOgCiUlGK6ocCvIGpfgs6Hzk4a5VN1ytL/VZ0IjeB7SZHcFYQ26nmhNoTk14E08Zmn3/QFYJsFaJ6sxDsn+Jd2KrI= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1789661164; c=relaxed/simple; bh=9mcxnDc8qxIpxmpk6T3Tp+BnQwg+ATLN/zS0rC02bj4=; h=Date:From:To:Cc:Subject:Message-ID:References:MIME-Version: Content-Type:Content-Disposition:In-Reply-To; b=h9FByVXMzEcCDDBbQ7RCCNMpyvVj9s9fZXRbUufRcrN695BZJDf2DLj9oMBu2Px2+GcnqrIUtk6rVGJmEteVKtn+9OkY3BYpt5RoDRr62y7SADwhAP/lKebE2/7p8Vm5xdpTri0xcd9iCMPfHDw40EL1IY1LR/2kNgrSHVqnxzw= ARC-Authentication-Results:i=1; smtp.subspace.kernel.org; dmarc=pass (p=none dis=none) header.from=arm.com; spf=pass smtp.mailfrom=arm.com; dkim=pass (1024-bit key) header.d=arm.com header.i=@arm.com header.b=iSTmFOj/; arc=none smtp.client-ip=217.140.110.172 Authentication-Results: smtp.subspace.kernel.org; dmarc=pass (p=none dis=none) header.from=arm.com Authentication-Results: smtp.subspace.kernel.org; spf=pass smtp.mailfrom=arm.com Authentication-Results: smtp.subspace.kernel.org; dkim=pass (1024-bit key) header.d=arm.com header.i=@arm.com header.b="iSTmFOj/" Received: from usa-sjc-imap-foss1.foss.arm.com (unknown [10.121.207.14]) by usa-sjc-mx-foss1.foss.arm.com (Postfix) with ESMTP id 723D01476; Thu, 17 Sep 2026 09:05:57 -0700 (PDT) Received: from arm.com (usa-sjc-mx-foss1.foss.arm.com [172.31.20.19]) by usa-sjc-imap-foss1.foss.arm.com (Postfix) with ESMTPSA id 0930A3F86F; Thu, 17 Sep 2026 09:05:55 -0700 (PDT) DKIM-Signature: v=1; a=rsa-sha256; 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> Precedence: bulk X-Mailing-List: linux-kernel@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: 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