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 3D7ACC4332F for ; Fri, 25 Nov 2022 15:50:50 +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=tigCkPFK4hdWWLjea3uExwPxTa6WEl1M+eDsJD8XIwc=; b=a3M5b0BSgBzlh6 NwS/Pd7ogTgYVhPJRt4H2C5Erl6VijCw1yYFRvY7iTiDE20fDasqOzhWL00ulEV1q5iT8sXlWECeT tsta8nTLbTYkOgJ2V3Q/hsFozGqckkEVXTXnPAikhX/tkRURU3gxWLm9SfMck84sYfUiAyN9uf7lG PBgBvrMjweQczdmgfmhFSW5klKgGOaedtG/hyQNTEKxHuD3T9bL1fC1SHaVia/jMukF4pOR089rGk YbfOz9EdJZOAb9vEWgXVO+CoQWn+If+bAHRBwre9SbYQYOsTgBGpFgwvXSvI5k2NFzEPg7QESAA1u xodNdpZeZwVJbrb9OoDw==; Received: from localhost ([::1] helo=bombadil.infradead.org) by bombadil.infradead.org with esmtp (Exim 4.94.2 #2 (Red Hat Linux)) id 1oyaxd-0001bm-D3; Fri, 25 Nov 2022 15:49:53 +0000 Received: from dfw.source.kernel.org ([2604:1380:4641:c500::1]) by bombadil.infradead.org with esmtps (Exim 4.94.2 #2 (Red Hat Linux)) id 1oyaxa-0001ao-Pu for linux-arm-kernel@lists.infradead.org; Fri, 25 Nov 2022 15:49:52 +0000 Received: from smtp.kernel.org (relay.kernel.org [52.25.139.140]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by dfw.source.kernel.org (Postfix) with ESMTPS id 468346250C; Fri, 25 Nov 2022 15:49:49 +0000 (UTC) Received: by smtp.kernel.org (Postfix) with ESMTPSA id 9F8C2C433D7; Fri, 25 Nov 2022 15:49:48 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=k20201202; t=1669391388; bh=J1n7A3Po/BvjIiR1JkMUhIHi/MIjb2B5HBeJvLmwlrc=; h=Date:From:To:Cc:Subject:References:In-Reply-To:From; b=IlJkXvd6UD0q9KHrp0K6eTAKTW+cDf93ng3pAFhU8yb2+8+Q2Xs0wtEAT6fCUkjj5 oZhNQoGestw7q/77t7S1TOKFWod64jyhVQzayoGxCppnVhIfn7WUkBl9Fh/Qa2NX2k 8nGl86ofw2ut2ByiUSDWTmrhXWVDljsV7RYZTltgGuLH/B4flQYbZnTGJrR02M4u++ g+2CSHQhFFq9GwUXKT0UWMTvG4D2u95+0tAt73qLX9FXLxRE5w+hy5hNq+ocm8pVE7 kEn6KL3kEcUENP0VM41/1pbKahH7k9fN+psf3fjR1BkdkwngmdBpPPezz+Al+vVqHt EZZ65d3HUhF8Q== Received: from johan by xi.lan with local (Exim 4.94.2) (envelope-from ) id 1oyax9-0006Zf-7R; Fri, 25 Nov 2022 16:49:23 +0100 Date: Fri, 25 Nov 2022 16:49:23 +0100 From: Johan Hovold To: Manivannan Sadhasivam Cc: Johan Hovold , Bjorn Andersson , Andy Gross , Konrad Dybcio , Rob Herring , Krzysztof Kozlowski , Will Deacon , Robin Murphy , Christoph Hellwig , Ard Biesheuvel , Catalin Marinas , linux-arm-msm@vger.kernel.org, linux-arm-kernel@lists.infradead.org, devicetree@vger.kernel.org, linux-kernel@vger.kernel.org Subject: Re: [PATCH] arm64: dts: qcom: sc8280xp: fix PCIe DMA coherency Message-ID: References: <20221124142501.29314-1-johan+linaro@kernel.org> <20221125142625.GA9892@thinkpad> <20221125145336.GB9892@thinkpad> MIME-Version: 1.0 Content-Disposition: inline In-Reply-To: <20221125145336.GB9892@thinkpad> X-CRM114-Version: 20100106-BlameMichelson ( TRE 0.8.0 (BSD) ) MR-646709E3 X-CRM114-CacheID: sfid-20221125_074950_892542_2DC38748 X-CRM114-Status: GOOD ( 16.53 ) 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: , Content-Type: text/plain; charset="us-ascii" Content-Transfer-Encoding: 7bit Sender: "linux-arm-kernel" Errors-To: linux-arm-kernel-bounces+linux-arm-kernel=archiver.kernel.org@lists.infradead.org On Fri, Nov 25, 2022 at 08:23:36PM +0530, Manivannan Sadhasivam wrote: > On Fri, Nov 25, 2022 at 03:43:59PM +0100, Johan Hovold wrote: > > On Fri, Nov 25, 2022 at 07:56:25PM +0530, Manivannan Sadhasivam wrote: > > > On Thu, Nov 24, 2022 at 03:25:01PM +0100, Johan Hovold wrote: > > I never claimed it would fix the problem, I explicitly wrote that it > > made it less likely to occur (to the point where my reproducer no longer > > triggers). > > > Increasing the buffer sizes to two pages to force CMA allocation also appears > > to make the problem go away. > > The "go away" part sounded like a claim to me and hence I added the statement. > But no worries :) Hopefully it's clear enough if you also read the preceding sentence (with emphasis added): presumably as these queues are small enough to not be allocated using CMA which in turn make them *more likely to be cached* (e.g. due to accesses to nearby pages through the cacheable linear map). Johan _______________________________________________ linux-arm-kernel mailing list linux-arm-kernel@lists.infradead.org http://lists.infradead.org/mailman/listinfo/linux-arm-kernel