From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1754985Ab0CYP2f (ORCPT ); Thu, 25 Mar 2010 11:28:35 -0400 Received: from g4t0014.houston.hp.com ([15.201.24.17]:25760 "EHLO g4t0014.houston.hp.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1754914Ab0CYP2a (ORCPT ); Thu, 25 Mar 2010 11:28:30 -0400 Subject: [PATCH 2/2] x86/PCI: truncate _CRS windows with _LEN > _MAX - _MIN + 1 To: Jesse Barnes From: Bjorn Helgaas Cc: linux-pci@vger.kernel.org, linux-kernel@vger.kernel.org, "Rafael J. Wysocki" , Yanko Kaneti , Linus Torvalds , Thomas Renninger , maciej.rutecki@gmail.com Date: Thu, 25 Mar 2010 09:28:30 -0600 Message-ID: <20100325152829.10117.91511.stgit@bob.kio> In-Reply-To: <20100325152750.10117.81615.stgit@bob.kio> References: <20100325152750.10117.81615.stgit@bob.kio> User-Agent: StGit/0.15 MIME-Version: 1.0 Content-Type: text/plain; charset="utf-8" Content-Transfer-Encoding: 7bit Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Yanko's GA-MA78GM-S2H (BIOS F11) reports the following resource in a PCI host bridge _CRS: [07] 32-Bit DWORD Address Space Resource Min Relocatability : MinFixed Max Relocatability : MaxFixed Address Minimum : CFF00000 (_MIN) Address Maximum : FEBFFFFF (_MAX) Address Length : 3EE10000 (_LEN) This is invalid per spec (ACPI 4.0, 6.4.3.5) because it's a fixed size, fixed location descriptor, but _LEN != _MAX - _MIN + 1. Based on https://bugzilla.kernel.org/show_bug.cgi?id=15480#c15, I think Windows handles this by truncating the window so it fits between _MIN and _MAX. I also verified this by modifying the SeaBIOS DSDT and booting Windows 2008 R2 with qemu. This patch makes Linux truncate the window, too, which fixes: http://bugzilla.kernel.org/show_bug.cgi?id=15480 Signed-off-by: Bjorn Helgaas Tested-by: Yanko Kaneti --- arch/x86/pci/acpi.c | 13 ++++++++++++- 1 files changed, 12 insertions(+), 1 deletions(-) diff --git a/arch/x86/pci/acpi.c b/arch/x86/pci/acpi.c index 75ac3f8..e311602 100644 --- a/arch/x86/pci/acpi.c +++ b/arch/x86/pci/acpi.c @@ -123,7 +123,7 @@ setup_resource(struct acpi_resource *acpi_res, void *data) acpi_status status; unsigned long flags; struct resource *root, *conflict; - u64 start, end; + u64 start, end, max_len; status = resource_to_addr(acpi_res, &addr); if (!ACPI_SUCCESS(status)) @@ -140,6 +140,17 @@ setup_resource(struct acpi_resource *acpi_res, void *data) } else return AE_OK; + max_len = addr.maximum - addr.minimum + 1; + if (addr.address_length > max_len) { + dev_printk(KERN_DEBUG, &info->bridge->dev, + "host bridge window length %#llx doesn't fit in " + "%#llx-%#llx, trimming\n", + (unsigned long long) addr.address_length, + (unsigned long long) addr.minimum, + (unsigned long long) addr.maximum); + addr.address_length = max_len; + } + start = addr.minimum + addr.translation_offset; end = start + addr.address_length - 1;