From mboxrd@z Thu Jan 1 00:00:00 1970 From: Bartlomiej Zolnierkiewicz Subject: Re: [PATCH 2.6.11.6] ide-scsi: kmap scatter/gather before doing PIO Date: Tue, 5 Apr 2005 22:27:36 +0200 Message-ID: <58cb370e0504051327751a19d8@mail.gmail.com> References: <7A8F92187EF7A249BF847F1BF4903C04010EEAF7@ausx2kmpc103.aus.amer.dell.com> Reply-To: Bartlomiej Zolnierkiewicz Mime-Version: 1.0 Content-Type: text/plain; charset=ISO-8859-1 Content-Transfer-Encoding: 7bit Return-path: Received: from wproxy.gmail.com ([64.233.184.192]:64726 "EHLO wproxy.gmail.com") by vger.kernel.org with ESMTP id S262006AbVDEU1j (ORCPT ); Tue, 5 Apr 2005 16:27:39 -0400 Received: by wproxy.gmail.com with SMTP id 68so565357wra for ; Tue, 05 Apr 2005 13:27:39 -0700 (PDT) In-Reply-To: <7A8F92187EF7A249BF847F1BF4903C04010EEAF7@ausx2kmpc103.aus.amer.dell.com> Sender: linux-ide-owner@vger.kernel.org List-Id: linux-ide@vger.kernel.org To: "Stuart_Hayes@dell.com" Cc: linux-ide@vger.kernel.org Hi, On Apr 5, 2005 9:12 PM, Stuart_Hayes@dell.com wrote: > > The system can panic with a null pointer dereference using ide-scsi if > PIO is being done on scatter gather pages that are in high memory, > because page_address() returns 0. We are actually seeing this using a > tape drive. This patch will kmap_atomic() the pages before performing > PIO. > > I'm copying the text here, but I'm also attaching it as a file, because > the text will get garbled with extra line breaks. > > Please let me know if there are any problems with the patch! Looks fine, I have two small requests: * please don't disable/enable local IRQs for !HIGHMEM case (see ide_pio_sector() in ide-taskfile.c) * declare 'unsigned long flags' at the beginning of the function > (I sent this patch to linux-scsi a few weeks ago, and I was finally told > that it is maintained by the IDE folks (Bartlomiej Zolnierkiewicz), not > the SCSI folks...) I'm not on linux-scsi, *sigh*, somebody could have simply forwarded it to me... Thanks! Bartlomiej