linux-kernel - [PATCH 4/4] PCI: Run ACPI _OSC method on root bridges only

lists.openwall.net		lists / announce owl-users owl-dev john-users john-dev passwdqc-users yescrypt popa3d-users / oss-security kernel-hardening musl sabotage tlsify passwords / crypt-dev xvendor / Bugtraq Full-Disclosure linux-kernel linux-netdev linux-ext4 linux-hardening linux-cve-announce PHC
Open Source and information security mailing list archives

Hash Suite: Windows password security audit tool. GUI, reports in PDF.

[<prev] [next>] [<thread-prev] [thread-next>] [day] [month] [year] [list]

Message-ID: <20080123001827.28190.7908.stgit@bluto.andrew>
Date:	Tue, 22 Jan 2008 17:18:27 -0700
From:	Andrew Patterson <andrew.patterson@...com>
To:	linux-pci@...r.kernel.org
Cc:	linux-kernel@...r.kernel.org, lenb@...nel.org, gregkh@...e.de,
	matthew@....cx, tom.l.nguyen@...el.com, linux-acpi@...r.kernel.org,
	Andrew Patterson <andrew.patterson@...com>
Subject: [PATCH 4/4] PCI: Run ACPI _OSC method on root bridges only

From: Andrew Patterson <andrew.patterson@...com>

According to the PCI Firmware Specification Revision 3.0 section 4.5, _OSC
should only be called on a root brdige.  Here is the relevant passage: "The
_OSC interface defined in this section applies only to Host Bridge ACPI
devices that originate PCI, PCI-X, or PCI Express hierarchies". Changed the
code to find the parent root bridge of the device and call _OSC on that.

Signed-off-by: Andrew Patterson <andrew.patterson@...com>
---

 drivers/pci/pcie/aer/aerdrv_acpi.c |   22 ++++++----------------
 1 files changed, 6 insertions(+), 16 deletions(-)

diff --git a/drivers/pci/pcie/aer/aerdrv_acpi.c b/drivers/pci/pcie/aer/aerdrv_acpi.c
index f685bf5..8c199ae 100644
--- a/drivers/pci/pcie/aer/aerdrv_acpi.c
+++ b/drivers/pci/pcie/aer/aerdrv_acpi.c
@@ -31,23 +31,13 @@ int aer_osc_setup(struct pcie_device *pciedev)
 {
 	acpi_status status = AE_NOT_FOUND;
 	struct pci_dev *pdev = pciedev->port;
-	acpi_handle handle = DEVICE_ACPI_HANDLE(&pdev->dev);
-	struct pci_bus *parent;
+	acpi_handle handle = 0;
 
-	while (!handle) {
-		if (!pdev || !pdev->bus->parent)
-			break;
-		parent = pdev->bus->parent;
-		if (!parent->self)
-			/* Parent must be a host bridge */
-			handle = acpi_get_pci_rootbridge_handle(
-					pci_domain_nr(parent),
-					parent->number);
-		else
-			handle = DEVICE_ACPI_HANDLE(
-					&(parent->self->dev));
-		pdev = parent->self;
-	}
+	/* Find root host bridge */
+	while (pdev->bus && pdev->bus->self)
+		pdev = pdev->bus->self;
+	handle = acpi_get_pci_rootbridge_handle(
+		pci_domain_nr(pdev->bus), pdev->bus->number);
 
 	if (handle) {
 		pcie_osc_support_set(OSC_EXT_PCI_CONFIG_SUPPORT);

--
To unsubscribe from this list: send the line "unsubscribe linux-kernel" in
the body of a message to majordomo@...r.kernel.org
More majordomo info at  http://vger.kernel.org/majordomo-info.html
Please read the FAQ at  http://www.tux.org/lkml/