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[34.124.234.44]) by smtp.gmail.com with ESMTPSA id 98e67ed59e1d1-367c2ccfbeasm8405a91.13.2026.05.08.07.53.11 (version=TLS1_3 cipher=TLS_AES_256_GCM_SHA384 bits=256/256); Fri, 08 May 2026 07:53:13 -0700 (PDT) Date: Fri, 8 May 2026 14:53:06 +0000 From: Pranjal Shrivastava To: Leo Jiang Cc: Will Deacon , Robin Murphy , joro@8bytes.org, iommu@lists.linux.dev, linux-arm-kernel@lists.infradead.org Subject: Re: [PATCH] iommu/arm-smmu-v3: Stop queue allocation retry at PAGE_SIZE Message-ID: References: <0fdf4b1f-90f2-4f69-9d2b-dc5f608e9c1c@arm.com> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: X-CRM114-Version: 20100106-BlameMichelson ( TRE 0.9.0 (BSD) ) MR-646709E3 X-CRM114-CacheID: sfid-20260508_075315_240606_98F39370 X-CRM114-Status: GOOD ( 14.86 ) X-BeenThere: linux-arm-kernel@lists.infradead.org X-Mailman-Version: 2.1.34 Precedence: list List-Id: List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Sender: "linux-arm-kernel" Errors-To: linux-arm-kernel-bounces+linux-arm-kernel=archiver.kernel.org@lists.infradead.org On Wed, Apr 22, 2026 at 05:13:08PM +0800, Leo Jiang wrote: > Hi Will, Robin, > > Thank you both for the detailed feedback. > > Robin, you are absolutely correct. After a deeper look into the source code, > I see that allocations smaller than a page are indeed possible in certain > cases. My previous assumption about the DMA API's granularity was wrong, > and I appreciate the correction. > > However, as Will noted that the current logic deviates from the original > intent, I have prepared a v2 to limit the queue allocation retry boundary > to PAGE_SIZE. > > In v2, I have: > - Updated my identity to Leo Jiang. > - Removed the code comments as suggested. > > I will send the v2 as a follow-up shortly. Hi Leo, The general guidance is to send the v2 as a fresh email so that it doesn't drop off the commmunity's radar. Thanks, Praan