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 vger.kernel.org (vger.kernel.org [23.128.96.18]) by smtp.lore.kernel.org (Postfix) with ESMTP id ED0D4C433EF for ; Mon, 23 May 2022 20:23:45 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S232917AbiEWUXn (ORCPT ); Mon, 23 May 2022 16:23:43 -0400 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:48902 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S232106AbiEWUXk (ORCPT ); Mon, 23 May 2022 16:23:40 -0400 Received: from dfw.source.kernel.org (dfw.source.kernel.org [139.178.84.217]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id E4214E0B3; Mon, 23 May 2022 13:23:39 -0700 (PDT) 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 5E38D614B6; Mon, 23 May 2022 20:23:39 +0000 (UTC) Received: by smtp.kernel.org (Postfix) with ESMTPSA id 45343C385AA; Mon, 23 May 2022 20:23:38 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=k20201202; t=1653337418; bh=cRmLCYxqZ/oPtyUyAbrJ2vSaCtJhJTaXonVzm1gzzZc=; h=Date:From:To:Cc:Subject:In-Reply-To:References:From; b=NKEVA1i2oilfkHiewDOhRCD2VgzU1ad8Meq+dybp0PEy6huQ+sA3jCZFN5B3i1p4d aRYuziRfx0xW0yhhxyrZns9P/1t2w7+H9uU2sxzu80/1JGRsKtt/rm0ybMQ9OLJIWG e8Avm6N7lI1+kCy5871Ae8jJr3GAFOKjB2jGLj4FI4ileAGPymwlmfonXfCTbb9xxC aZsaB4ZlkKHmOhwUJrFihy0GKOaOxUsG34Bz1WdBxHvLAcz3Ms+pc4KtNG+gLpktCx LrLFA9YVBGMML3Tt9+tMZRG+GpwUqWhE4CixX67CBqFQJg1Hv9GvMN/fRR39N5hRFx TO1c31n0Wvamg== Date: Mon, 23 May 2022 13:23:36 -0700 From: Jakub Kicinski To: Christophe Leroy Cc: =?UTF-8?B?TcOlbnMgUnVsbGfDpXJk?= , Pantelis Antoniou , "David S. Miller" , Eric Dumazet , Paolo Abeni , Vitaly Bordug , Dan Malek , Joakim Tjernlund , "linuxppc-dev@lists.ozlabs.org" , "netdev@vger.kernel.org" , "linux-kernel@vger.kernel.org" Subject: Re: [PATCH] net: fs_enet: sync rx dma buffer before reading Message-ID: <20220523132336.073965a5@kernel.org> In-Reply-To: <20220521104430.1212bed5@kernel.org> References: <20220519192443.28681-1-mans@mansr.com> <03f24864-9d4d-b4f9-354a-f3b271c0ae66@csgroup.eu> <20220520104347.2b1b658a@kernel.org> <20220521104430.1212bed5@kernel.org> MIME-Version: 1.0 Content-Type: text/plain; charset=US-ASCII Content-Transfer-Encoding: 7bit Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On Sat, 21 May 2022 10:44:30 -0700 Jakub Kicinski wrote: > > Well, I say the contrary. > > > > On the mainline the patch may be applied as is, it won't harm. > > > > However, it is gets applied to kernel 4.9 (based on the fixes: tag), it > > will break the driver for at least powerpc 8xx. > > I see, we should make a note of that in the commit message so it doesn't > get sucked into stable. > > > I don't know how SWIOTLB works or even what it is, does any of the > > microcontrollers embedding freescale ethernet uses that at all ? > > AFAIU SWIOTLB basically forces the use of bounce buffers even if the > device can reach the entire DRAM. I think some people also use it for > added security? IDK. I mostly use it to check if I'm using the DMA API > "right" :) If what I said makes sense please repost the patch, the current version has been dropped from patchwork already. 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 lists.ozlabs.org (lists.ozlabs.org [112.213.38.117]) (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 6DFC1C433F5 for ; Mon, 23 May 2022 20:24:22 +0000 (UTC) Received: from boromir.ozlabs.org (localhost [IPv6:::1]) by lists.ozlabs.org (Postfix) with ESMTP id 4L6TM86Yw7z3c7S for ; Tue, 24 May 2022 06:24:20 +1000 (AEST) Authentication-Results: lists.ozlabs.org; dkim=fail reason="signature verification failed" (2048-bit key; unprotected) header.d=kernel.org header.i=@kernel.org header.a=rsa-sha256 header.s=k20201202 header.b=NKEVA1i2; dkim-atps=neutral Authentication-Results: lists.ozlabs.org; spf=pass (sender SPF authorized) smtp.mailfrom=kernel.org (client-ip=2604:1380:4641:c500::1; helo=dfw.source.kernel.org; envelope-from=kuba@kernel.org; receiver=) Authentication-Results: lists.ozlabs.org; dkim=pass (2048-bit key; unprotected) header.d=kernel.org header.i=@kernel.org header.a=rsa-sha256 header.s=k20201202 header.b=NKEVA1i2; dkim-atps=neutral Received: from dfw.source.kernel.org (dfw.source.kernel.org [IPv6:2604:1380:4641:c500::1]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by lists.ozlabs.org (Postfix) with ESMTPS id 4L6TLR0GNbz305b for ; Tue, 24 May 2022 06:23:42 +1000 (AEST) 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 5A8AE61495; Mon, 23 May 2022 20:23:39 +0000 (UTC) Received: by smtp.kernel.org (Postfix) with ESMTPSA id 45343C385AA; Mon, 23 May 2022 20:23:38 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=k20201202; t=1653337418; bh=cRmLCYxqZ/oPtyUyAbrJ2vSaCtJhJTaXonVzm1gzzZc=; h=Date:From:To:Cc:Subject:In-Reply-To:References:From; b=NKEVA1i2oilfkHiewDOhRCD2VgzU1ad8Meq+dybp0PEy6huQ+sA3jCZFN5B3i1p4d aRYuziRfx0xW0yhhxyrZns9P/1t2w7+H9uU2sxzu80/1JGRsKtt/rm0ybMQ9OLJIWG e8Avm6N7lI1+kCy5871Ae8jJr3GAFOKjB2jGLj4FI4ileAGPymwlmfonXfCTbb9xxC aZsaB4ZlkKHmOhwUJrFihy0GKOaOxUsG34Bz1WdBxHvLAcz3Ms+pc4KtNG+gLpktCx LrLFA9YVBGMML3Tt9+tMZRG+GpwUqWhE4CixX67CBqFQJg1Hv9GvMN/fRR39N5hRFx TO1c31n0Wvamg== Date: Mon, 23 May 2022 13:23:36 -0700 From: Jakub Kicinski To: Christophe Leroy Subject: Re: [PATCH] net: fs_enet: sync rx dma buffer before reading Message-ID: <20220523132336.073965a5@kernel.org> In-Reply-To: <20220521104430.1212bed5@kernel.org> References: <20220519192443.28681-1-mans@mansr.com> <03f24864-9d4d-b4f9-354a-f3b271c0ae66@csgroup.eu> <20220520104347.2b1b658a@kernel.org> <20220521104430.1212bed5@kernel.org> MIME-Version: 1.0 Content-Type: text/plain; charset=US-ASCII Content-Transfer-Encoding: 7bit X-BeenThere: linuxppc-dev@lists.ozlabs.org X-Mailman-Version: 2.1.29 Precedence: list List-Id: Linux on PowerPC Developers Mail List List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Cc: =?UTF-8?B?TcOlbnMgUnVsbGfDpXJk?= , "linuxppc-dev@lists.ozlabs.org" , Dan Malek , "linux-kernel@vger.kernel.org" , Eric Dumazet , "netdev@vger.kernel.org" , Vitaly Bordug , Paolo Abeni , Joakim Tjernlund , "David S. Miller" Errors-To: linuxppc-dev-bounces+linuxppc-dev=archiver.kernel.org@lists.ozlabs.org Sender: "Linuxppc-dev" On Sat, 21 May 2022 10:44:30 -0700 Jakub Kicinski wrote: > > Well, I say the contrary. > > > > On the mainline the patch may be applied as is, it won't harm. > > > > However, it is gets applied to kernel 4.9 (based on the fixes: tag), it > > will break the driver for at least powerpc 8xx. > > I see, we should make a note of that in the commit message so it doesn't > get sucked into stable. > > > I don't know how SWIOTLB works or even what it is, does any of the > > microcontrollers embedding freescale ethernet uses that at all ? > > AFAIU SWIOTLB basically forces the use of bounce buffers even if the > device can reach the entire DRAM. I think some people also use it for > added security? IDK. I mostly use it to check if I'm using the DMA API > "right" :) If what I said makes sense please repost the patch, the current version has been dropped from patchwork already.