From mboxrd@z Thu Jan 1 00:00:00 1970 From: Fabio Estevam Subject: Re: [PATCH] serial: imx: disable DMA for RS-485 on i.MX6 SMP Date: Wed, 21 Jun 2017 11:12:23 -0300 Message-ID: References: <20170620153701.12626-1-clemens.gruber@pqgruber.com> <20170621140556.GA766@archie.localdomain> Mime-Version: 1.0 Content-Type: text/plain; charset="UTF-8" Return-path: In-Reply-To: <20170621140556.GA766@archie.localdomain> Sender: linux-kernel-owner@vger.kernel.org To: Clemens Gruber Cc: "linux-serial@vger.kernel.org" , Greg Kroah-Hartman , Fabio Estevam , =?UTF-8?Q?Uwe_Kleine=2DK=C3=B6nig?= , linux-kernel , Fugang Duan List-Id: linux-serial@vger.kernel.org Hi Clemens, On Wed, Jun 21, 2017 at 11:05 AM, Clemens Gruber wrote: > > I'd also prefer fixing the underlying problem. Yes, that would be much better. > If you take a look at the DMA parts in drivers/tty/serial/imx.c, can you > spot anything SMP-unsafe? Not really. > By the way, can you get your hands on an i.MX6Q board with RS-485 to > reproduce it? Unfortunately I don't have such hardware. Even the mx6solo board that I used to have access in the past I do not have it anymore. > We could try for a few more weeks to find the bug and if we don't find > it, adding this rs485-enabled-at-boot-time property sounds good! Sounds like a good plan, thanks.