From mboxrd@z Thu Jan 1 00:00:00 1970 From: Miles Lane Subject: The nvidiafb driver is requiring too much vmalloc space and other problems. Date: Wed, 30 Mar 2005 14:59:09 -0800 Message-ID: Reply-To: linux-fbdev-devel@lists.sourceforge.net Mime-Version: 1.0 Content-Transfer-Encoding: 7bit Return-path: Received: from sc8-sf-mx1-b.sourceforge.net ([10.3.1.11] helo=sc8-sf-mx1.sourceforge.net) by sc8-sf-list1.sourceforge.net with esmtp (Exim 4.30) id 1DGm9r-0005Nj-NX for linux-fbdev-devel@lists.sourceforge.net; Wed, 30 Mar 2005 14:59:31 -0800 Received: from wproxy.gmail.com ([64.233.184.195]) by sc8-sf-mx1.sourceforge.net with esmtp (Exim 4.41) id 1DGm9b-0005BA-6p for linux-fbdev-devel@lists.sourceforge.net; Wed, 30 Mar 2005 14:59:31 -0800 Received: by wproxy.gmail.com with SMTP id 69so353698wra for ; Wed, 30 Mar 2005 14:59:09 -0800 (PST) Sender: linux-fbdev-devel-admin@lists.sourceforge.net Errors-To: linux-fbdev-devel-admin@lists.sourceforge.net List-Unsubscribe: , List-Id: List-Post: List-Help: List-Subscribe: , List-Archive: Content-Type: text/plain; charset="us-ascii" To: linux-fbdev-devel@lists.sourceforge.net, "Randy.Dunlap" , Andrew Morton , "Antonino A. Daplas" Hello, With guidance from Randy Dunlap, it has been determined that the nvidiafb driver will fail to operate correctly unless more than 128M of memory is provided by using "vmalloc=". The default kernel configuration provides for 128M, but Randy found that: >I started looking at vmalloc() and what it calls (which is > __get_vm_area). _get_vm_area() always allocates one extra > page (called a "guard page") between all vmalloc allocations, > so even though 128 MB is the default amount and the amount > that nvidiafb wants to use, the kernel wants to allocate > 128 MB + PAGE_SIZE (4 KB on x86; are you on x86?), so even > if nvidiafb is the only caller, the vmalloc() call will fail. Booting with vmalloc=256M works, but Andrew thinks that nvidiafb should not be requiring 128M in the first place. Regarding the problems with i2c bit-banging drivers, I don't know if the Oops I have been getting is related to the vmalloc issue somehow. Comments? I'll try to repro the crash with vmalloc=256M set. Lastly, with vmalloc=256M, my machine crashes whenever I try to switch from XFree86 to a framebuffer console. I cannot see the oops. Unfortunately, the only machine I could use for debugging using a serial connection is a Powerbook, which has no serial port. I could try setting up dumping the stack over the network, but I have never tried to do this before and do not know whether I can do the dump to a Powerbook running OS/X. Any suggestions? Thanks, Miles ------------------------------------------------------- This SF.net email is sponsored by Demarc: A global provider of Threat Management Solutions. Download our HomeAdmin security software for free today! http://www.demarc.com/info/Sentarus/hamr30