Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S965455AbeAJMZ7 (ORCPT + 1 other); Wed, 10 Jan 2018 07:25:59 -0500 Received: from mail-wm0-f68.google.com ([74.125.82.68]:45259 "EHLO mail-wm0-f68.google.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S964832AbeAJMZ4 (ORCPT ); Wed, 10 Jan 2018 07:25:56 -0500 X-Google-Smtp-Source: ACJfBouvx2vV2tEAeaw8rnS6MmJNtIxaN7jc+H7rb9ZlKwmn/mZbsVcIbv4uNZEk7IruxgbODefzog== From: "=?UTF-8?q?Christian=20K=C3=B6nig?=" X-Google-Original-From: =?UTF-8?q?Christian=20K=C3=B6nig?= To: bhelgaas@google.com Cc: linux-kernel@vger.kernel.org Subject: [PATCH 2/2] x86/PCI: limit the size of the 64bit window to 256GB v2 Date: Wed, 10 Jan 2018 13:25:51 +0100 Message-Id: <20180110122551.1637-2-christian.koenig@amd.com> X-Mailer: git-send-email 2.11.0 In-Reply-To: <20180110122551.1637-1-christian.koenig@amd.com> References: <20180110122551.1637-1-christian.koenig@amd.com> MIME-Version: 1.0 Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 8bit Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Return-Path: Avoid problems with BIOS implementations which don't report all used resources to the OS by only allocating a 256GB window directly below the hardware limit. v2: cleanup code a bit more, update comment and explain the hw limit Signed-off-by: Christian König --- arch/x86/pci/fixup.c | 19 +++++++++---------- 1 file changed, 9 insertions(+), 10 deletions(-) diff --git a/arch/x86/pci/fixup.c b/arch/x86/pci/fixup.c index a91280da2ea1..9c1c98d7e3a7 100644 --- a/arch/x86/pci/fixup.c +++ b/arch/x86/pci/fixup.c @@ -662,10 +662,11 @@ DECLARE_PCI_FIXUP_EARLY(PCI_VENDOR_ID_INTEL, 0x2033, quirk_no_aersid); */ static void pci_amd_enable_64bit_bar(struct pci_dev *dev) { - unsigned i; u32 base, limit, high; - struct resource *res, *conflict; struct pci_dev *other; + struct resource *res; + unsigned i; + int r; if (!(pci_probe & PCI_BIG_ROOT_WINDOW)) return; @@ -702,19 +703,17 @@ static void pci_amd_enable_64bit_bar(struct pci_dev *dev) if (!res) return; + /* Allocate a 256GB window directly below the 0xfd00000000 hw limit */ res->name = "PCI Bus 0000:00"; res->flags = IORESOURCE_PREFETCH | IORESOURCE_MEM | IORESOURCE_MEM_64 | IORESOURCE_WINDOW; - res->start = 0x100000000ull; + res->start = 0xbd00000000ull; res->end = 0xfd00000000ull - 1; - /* Just grab the free area behind system memory for this */ - while ((conflict = request_resource_conflict(&iomem_resource, res))) { - if (conflict->end >= res->end) { - kfree(res); - return; - } - res->start = conflict->end + 1; + r = request_resource(&iomem_resource, res); + if (r) { + kfree(res); + return; } dev_info(&dev->dev, "adding root bus resource %pR\n", res); -- 2.11.0