From owner-freebsd-questions@FreeBSD.ORG Mon Jun 22 17:51:53 2015 Return-Path: Delivered-To: freebsd-questions@nevdull.freebsd.org Received: from mx1.freebsd.org (mx1.freebsd.org [IPv6:2001:1900:2254:206a::19:1]) (using TLSv1.2 with cipher AECDH-AES256-SHA (256/256 bits)) (No client certificate requested) by hub.freebsd.org (Postfix) with ESMTPS id 316FCAA3 for ; Mon, 22 Jun 2015 17:51:53 +0000 (UTC) (envelope-from jd1008@gmail.com) Received: from mail-ie0-x22b.google.com (mail-ie0-x22b.google.com [IPv6:2607:f8b0:4001:c03::22b]) (using TLSv1.2 with cipher ECDHE-RSA-AES128-GCM-SHA256 (128/128 bits)) (Client CN "smtp.gmail.com", Issuer "Google Internet Authority G2" (verified OK)) by mx1.freebsd.org (Postfix) with ESMTPS id ED145E80 for ; Mon, 22 Jun 2015 17:51:52 +0000 (UTC) (envelope-from jd1008@gmail.com) Received: by iebrt9 with SMTP id rt9so9465820ieb.2 for ; Mon, 22 Jun 2015 10:51:52 -0700 (PDT) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=gmail.com; s=20120113; h=message-id:date:from:user-agent:mime-version:to:subject:references :in-reply-to:content-type:content-transfer-encoding; bh=cFvS0+BWXJedZfICTSVPsGjiJrYRxeHgo56F0zl5XXQ=; b=HVXKqJRI98k0638795AZIC2a36L5Lv276LMzO6SYLtcCim4QL+iaHcuJSNbsoZEKwE 6IFkkuaOeJjIrSu0IrJK0EHk5RPhbNCbi1QJonEo45cjjNgAztZ7Ow/c8fcNuKwgC/R/ bzKvTgraolVHUu85/3e2DiyK7yQcfcaERN1xoZcIRawx6UATA4KwC86OxaK3a+wNo/kO chSWdZSBWXGS3xKZvLgoGdR+8OadcJkKimG6CAH/UOg2JnAkakfgMDWup85f0VyLc9Ln LdEMbwd/uZcd9DGESUvqFYtw603O7koPdZY/VpIp2huNCjXJP03HCz1TVAVd7Tz1z+Af olzw== X-Received: by 10.107.25.199 with SMTP id 190mr41162530ioz.11.1434995512372; Mon, 22 Jun 2015 10:51:52 -0700 (PDT) Received: from localhost.localdomain ([50.243.6.59]) by mx.google.com with ESMTPSA id w4sm7950597igl.22.2015.06.22.10.51.51 for (version=TLSv1.2 cipher=ECDHE-RSA-AES128-GCM-SHA256 bits=128/128); Mon, 22 Jun 2015 10:51:51 -0700 (PDT) Message-ID: <55884B36.8000007@gmail.com> Date: Mon, 22 Jun 2015 11:51:50 -0600 From: jd1008 User-Agent: Mozilla/5.0 (X11; Linux x86_64; rv:31.0) Gecko/20100101 Thunderbird/31.7.0 MIME-Version: 1.0 To: freebsd-questions@freebsd.org Subject: Re: How to test for memory corruption ? References: In-Reply-To: Content-Type: text/plain; charset=utf-8; format=flowed Content-Transfer-Encoding: 8bit X-BeenThere: freebsd-questions@freebsd.org X-Mailman-Version: 2.1.20 Precedence: list List-Id: User questions List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , X-List-Received-Date: Mon, 22 Jun 2015 17:51:53 -0000 On 06/22/2015 02:10 AM, Daniel Peyrolon wrote: > Hi, > > I have absolutely no idea, but maybe you can use DTrace for this? > > You could also print the location for each memory write. > > El sáb., 20 de junio de 2015 9:20, Pratik Singhal > escribió: > >> Hello, I have written code for adding support for DMA transfers for >> Allwinner A10 SoC (Cubieboard 1) in MMC driver/ >> >> I have tried transferring files to/from mmc card and verified that files >> are copied fine. >> Although, many times the kernel panics suddenly, after I transfer files. >> This does not happen If I use PIO to transfer data (PIO's code is tested >> and already committed to ~HEAD). Panics don't occur in the statements >> written for DMA transfer. >> >> I am suspecting that the problem is that the DMA transfer apart from >> writing where it is required, is overwriting other parts of the memory >> also. >> >> Is there any way, I can verify that this is/this is not the case ? >> >> Thank you, >> Pratik Singhal It would be helpful to the devs if you post a link to the source code of your dma support code and all the mods you made in support thereof.