From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: X-Spam-Checker-Version: SpamAssassin 3.4.0 (2014-02-07) on aws-us-west-2-korg-lkml-1.web.codeaurora.org Received: from bombadil.infradead.org (bombadil.infradead.org [198.137.202.133]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by smtp.lore.kernel.org (Postfix) with ESMTPS id D4BB3CA5FED for ; Tue, 6 Oct 2026 21:52:56 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; q=dns/txt; c=relaxed/relaxed; d=lists.infradead.org; s=bombadil.20210309; h=Sender: Content-Transfer-Encoding:Content-Type:List-Subscribe:List-Help:List-Post: List-Archive:List-Unsubscribe:List-Id:In-Reply-To:MIME-Version:References: Message-ID:Subject:Cc:To:From:Date:Reply-To:Content-ID:Content-Description: Resent-Date:Resent-From:Resent-Sender:Resent-To:Resent-Cc:Resent-Message-ID: List-Owner; bh=RiOdgyVZITUaGD9q8Z31CgvNKCeVcvIiFg/MWafhZBY=; b=WxWvcYYU5mnUnU Ic16buaL1iphD5y9EYX7zOslZ5erDJHZG+TVf+iIVXQYqmAH6eyTWZ/ja8R4ocs06a4tDUmXYjDxc YSE1k5kqrtwj9v+n2H3RhZuZe52boPdgomykuDMpKVTJJk3lN0MXHPdDCD78cl23653xCAJNlKQF0 HHc30uTdkla/7NPrH79qUdNB4nWDch5dkS04B513ncikiUmdt7nK9fc/x0eHwjW/1EnEN9Do7yfRN nTP9k1vIvW2elyCW0OuV+TMqUJg/7tVLkESs7AP57e8+WJO2gCERFwFC+2hOhrMFec/6WrJ7uUHci 3kpfFu22zpEMoB255T0A==; Received: from localhost ([::1] helo=bombadil.infradead.org) by bombadil.infradead.org with esmtp (Exim 4.99.1 #2 (Red Hat Linux)) id 1xED5Y-00000001QRQ-3OSD; Tue, 06 Oct 2026 21:52:44 +0000 Received: from sea.source.kernel.org ([172.234.252.31]) by bombadil.infradead.org with esmtps (Exim 4.99.1 #2 (Red Hat Linux)) id 1xED5X-00000001QR4-0ufX; Tue, 06 Oct 2026 21:52:43 +0000 Received: from smtp.kernel.org (quasi.space.kernel.org [100.103.45.18]) by sea.source.kernel.org (Postfix) with ESMTP id 4B2F643AE3; Tue, 6 Oct 2026 21:52:42 +0000 (UTC) Received: by smtp.kernel.org (Postfix) with ESMTPSA id 4D5A61F0089B; Tue, 6 Oct 2026 21:52:32 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=kernel.org; s=k20260515; t=1791323562; bh=aLltj2KeDqF9OosT0AEoWFskj5jYY5VnqnzaqsV3VgY=; h=Date:From:To:Cc:Subject:References:In-Reply-To; b=Ftqi5JxYQ7+lOH0e3/qLZoDI1z82JKInnQfYcKqixAXYDv4KmRLetT2yf6MF8YU1u kUk9ToRlzIe8Nl1vp2TYck54k5ulwPMNvsOqte7ISHa1gh1TIEKVm+Z5mbwpXSF1AD crVr7MkSiyiM2du+fk37Zp93ECnO4ni6RGEVcicG7VzMtvaS8p6SOzT+i9R5N0nIz1 /esNqVbVK14/jTVs7oNE7q6G/lw1RUNITEX+RT16CVY0u83mLVBpntBf5Str+DsaJe LT4RGmc1J/WMANFyagqs0E7dcbEUuVDQE0vhXKYthrpnZNsogcBHN1Y8oBt35CXUDx Enb5fk2CRE8Ww== Date: Tue, 6 Oct 2026 22:52:29 +0100 From: Will Deacon To: Marek Szyprowski Cc: "Aneesh Kumar K.V (Arm)" , iommu@lists.linux.dev, linux-kernel@vger.kernel.org, Robin Murphy , Jonathan Corbet , Shuah Khan , Randy Dunlap , Mark Rutland , Marc Zyngier , Steven Price , Suzuki K Poulose , Catalin Marinas , Jiri Pirko , Jason Gunthorpe , Mostafa Saleh , Petr Tesarik , Alexey Kardashevskiy , Dan Williams , Xu Yilun , Madhavan Srinivasan , Michael Ellerman , Nicholas Piggin , "Christophe Leroy (CS GROUP)" , "Ritesh Harjani (IBM)" , Shrikanth Hegde , Alexander Gordeev , Gerald Schaefer , Heiko Carstens , Vasily Gorbik , Christian Borntraeger , Sven Schnelle , Stefano Stabellini , Russell King , Huacai Chen , WANG Xuerui , Thomas Bogendoerfer , Jiaxun Yang , Paul Walmsley , Palmer Dabbelt , Albert Ou , Alexandre Ghiti , Andy Lutomirski , Peter Zijlstra , Thomas Gleixner , Ingo Molnar , Borislav Petkov , Dave Hansen , "H. Peter Anvin" , 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 v6 0/8] dma: swiotlb: Centralize default pool policy and sizing Message-ID: References: <20260924060756.1325156-1-aneesh.kumar@kernel.org> MIME-Version: 1.0 Content-Disposition: inline In-Reply-To: X-BeenThere: linux-riscv@lists.infradead.org X-Mailman-Version: 2.1.34 Precedence: list List-Id: List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Content-Type: text/plain; charset="us-ascii" Content-Transfer-Encoding: 7bit Sender: "linux-riscv" Errors-To: linux-riscv-bounces+linux-riscv=archiver.kernel.org@lists.infradead.org On Tue, Oct 06, 2026 at 11:42:54PM +0200, Marek Szyprowski wrote: > On 24.09.2026 08:07, Aneesh Kumar K.V (Arm) wrote: > > This series centralizes swiotlb default-pool selection and sizing, and > > simplifies the initialization flags used to describe pool placement. > > > > The first patch replaces the addressing-limit argument with initialization > > flags and introduces explicit policies for the different reasons a default > > pool may be needed. Architectures now report DMA addressing constraints with > > SWIOTLB_INIT_ADDRESSING_LIMIT, while the core selects the corresponding pool > > policy. > > > > The second patch moves the reduced sizing used when the pool is needed only > > for unaligned kmalloc bouncing from arm64 and RISC-V into the swiotlb core. > > > > The third patch centralizes swiotlb sizing for memory-encrypted systems. It > > moves the existing x86 guest-sizing policy into the core. Host memory > > encryption retains the normal pool size, and a shared default pool is not > > selected solely for guest memory encryption when a restricted DMA pool is > > present. > > > > The fourth patch removes SWIOTLB_ANY. Pool placement is derived directly from > > SWIOTLB_INIT_ADDRESSING_LIMIT: pools required for limited DMA addressing are > > allocated below the architecture's low address limit, while other pools may > > be allocated anywhere in directly mapped memory. Xen continues to request a > > pool explicitly with SWIOTLB_INIT_REMAP without imposing a low-address > > constraint. > > > I will give this patchset a chance in linux-next. If one feels that it still needs > to be improved or sees any other reason why it shouldn't be merged, let me know > asap. I think the restricted-dma pool heuristic is horribly naive, so please drop that part for now. Will _______________________________________________ linux-riscv mailing list linux-riscv@lists.infradead.org http://lists.infradead.org/mailman/listinfo/linux-riscv