Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id ; Fri, 29 Mar 2002 10:08:49 -0500 Received: (majordomo@vger.kernel.org) by vger.kernel.org id ; Fri, 29 Mar 2002 10:08:40 -0500 Received: from twilight.ucw.cz ([195.39.74.230]:13219 "EHLO twilight.ucw.cz") by vger.kernel.org with ESMTP id ; Fri, 29 Mar 2002 10:08:26 -0500 Date: Fri, 29 Mar 2002 16:08:18 +0100 From: Vojtech Pavlik To: Mikael Pettersson Cc: linux-kernel@vger.kernel.org, martin@dalecki.de Subject: Re: 2.5.7 pre-UDMA PIIX bug Message-ID: <20020329160818.A30814@ucw.cz> In-Reply-To: <200203291239.NAA25704@harpo.it.uu.se> Mime-Version: 1.0 Content-Type: multipart/mixed; boundary="yrj/dFKFPuw6o+aM" Content-Disposition: inline User-Agent: Mutt/1.2.5i Sender: linux-kernel-owner@vger.kernel.org X-Mailing-List: linux-kernel@vger.kernel.org --yrj/dFKFPuw6o+aM Content-Type: text/plain; charset=us-ascii Content-Disposition: inline On Fri, Mar 29, 2002 at 01:39:56PM +0100, Mikael Pettersson wrote: > Vojtech's version of drivers/ide/piix.c which went into 2.5.7 > oopses with a divide-by-zero exception when initialising older > pre-UDMA chips, like in the following 430HX chipset: > > 00:00.0 Host bridge: Intel Corporation 430HX - 82439HX TXC [Triton II] (rev 03) > 00:07.0 ISA bridge: Intel Corporation 82371SB PIIX3 ISA [Natoma/Triton II] (rev 01) > 00:07.1 IDE interface: Intel Corporation 82371SB PIIX3 IDE [Natoma/Triton II] > (PCI IDs 8086:1250, 8086:7000, and 8086:7010, respectively) > > The error occurs in piix.c:piix_set_drive() line 334, shown below. > The 82371SB has PIIX_UDMA_NONE in the piix_ide_chips[] array, > so piix_config->flags & PIIX_UDMA is zero, which makes "umul" zero, > which causes the divide-by-zero on line 334. > > 317 static int piix_set_drive(ide_drive_t *drive, unsigned char speed) > 318 { > 319 ide_drive_t *peer = HWIF(drive)->drives + (~drive->dn & 1); > 320 struct ata_timing t, p; > 321 int err, T, UT, umul; > 322 > 323 if (speed != XFER_PIO_SLOW && speed != drive->current_speed) > 324 if ((err = ide_config_drive_speed(drive, speed))) > 325 return err; > 326 > 327 umul = min((speed > XFER_UDMA_4) ? 4 : ((speed > XFER_UDMA_2) ? 2 : 1), > 328 piix_config->flags & PIIX_UDMA); > 329 > 330 if (piix_config->flags & PIIX_VICTORY) > 331 umul = 2; > 332 > 333 T = 1000000000 / piix_clock; > 334 UT = T / umul; Thanks for the bug report! The attached patch should fix that. Martin, please apply this patch. -- Vojtech Pavlik SuSE Labs --yrj/dFKFPuw6o+aM Content-Type: text/plain; charset=us-ascii Content-Disposition: attachment; filename="fixpiix.diff" diff -urN linux-2.5.7/drivers/ide/piix.c linux-2.5.7-fixpiix/drivers/ide/piix.c --- linux-2.5.7/drivers/ide/piix.c Fri Mar 29 16:01:51 2002 +++ linux-2.5.7-fixpiix/drivers/ide/piix.c Fri Mar 29 16:07:05 2002 @@ -1,5 +1,5 @@ /* - * $Id: piix.c,v 1.2 2002/03/13 22:50:43 vojtech Exp $ + * $Id: piix.c,v 1.3 2002/03/29 16:06:06 vojtech Exp $ * * Copyright (c) 2000-2002 Vojtech Pavlik * @@ -128,7 +128,7 @@ piix_print("----------PIIX BusMastering IDE Configuration---------------"); - piix_print("Driver Version: 1.2"); + piix_print("Driver Version: 1.3"); piix_print("South Bridge: %s", bmide_dev->name); pci_read_config_byte(dev, PCI_REVISION_ID, &t); @@ -331,7 +331,7 @@ umul = 2; T = 1000000000 / piix_clock; - UT = T / umul; + UT = umul ? (T / umul) : 0; ata_timing_compute(drive, speed, &t, T, UT); --yrj/dFKFPuw6o+aM-- - To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to majordomo@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/