linux-kernel - [PATCH v2 3/8] PCI: Restore resource alignment

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: <20240716193246.1909697-4-stewart.hildebrand@amd.com>
Date: Tue, 16 Jul 2024 15:32:33 -0400
From: Stewart Hildebrand <stewart.hildebrand@....com>
To: Bjorn Helgaas <bhelgaas@...gle.com>
CC: Stewart Hildebrand <stewart.hildebrand@....com>,
	<linux-pci@...r.kernel.org>, <linux-kernel@...r.kernel.org>
Subject: [PATCH v2 3/8] PCI: Restore resource alignment

Devices with alignment specified will lose their alignment in cases when
the bridge resources have been released, e.g. due to insufficient bridge
window size. Restore the alignment.

Signed-off-by: Stewart Hildebrand <stewart.hildebrand@....com>
---
v1->v2:
* capitalize subject text
---
 drivers/pci/setup-bus.c | 19 +++++++++++++++++++
 1 file changed, 19 insertions(+)

diff --git a/drivers/pci/setup-bus.c b/drivers/pci/setup-bus.c
index 23082bc0ca37..ab7510ce6917 100644
--- a/drivers/pci/setup-bus.c
+++ b/drivers/pci/setup-bus.c
@@ -1594,6 +1594,23 @@ static void __pci_bridge_assign_resources(const struct pci_dev *bridge,
 	}
 }
 
+static void restore_child_resource_alignment(struct pci_bus *bus)
+{
+	struct pci_dev *dev;
+
+	list_for_each_entry(dev, &bus->devices, bus_list) {
+		struct pci_bus *b;
+
+		pci_reassigndev_resource_alignment(dev);
+
+		b = dev->subordinate;
+		if (!b)
+			continue;
+
+		restore_child_resource_alignment(b);
+	}
+}
+
 #define PCI_RES_TYPE_MASK \
 	(IORESOURCE_IO | IORESOURCE_MEM | IORESOURCE_PREFETCH |\
 	 IORESOURCE_MEM_64)
@@ -1648,6 +1665,8 @@ static void pci_bridge_release_resources(struct pci_bus *bus,
 		r->start = 0;
 		r->flags = 0;
 
+		restore_child_resource_alignment(bus);
+
 		/* Avoiding touch the one without PREF */
 		if (type & IORESOURCE_PREFETCH)
 			type = IORESOURCE_PREFETCH;
-- 
2.45.2