linux-kernel - [PATCH v2 1/2] PCI: don't rely on of_platform

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: <20240819082445.10248-2-brgl@bgdev.pl>
Date: Mon, 19 Aug 2024 10:24:43 +0200
From: Bartosz Golaszewski <brgl@...ev.pl>
To: Bjorn Helgaas <bhelgaas@...gle.com>
Cc: linux-pci@...r.kernel.org,
	linux-kernel@...r.kernel.org,
	Bartosz Golaszewski <bartosz.golaszewski@...aro.org>
Subject: [PATCH v2 1/2] PCI: don't rely on of_platform_depopulate() for reused OF-nodes

From: Bartosz Golaszewski <bartosz.golaszewski@...aro.org>

of_platform_depopulate() doesn't play nice with reused OF nodes - it
ignores the ones that are not marked explicitly as populated and it may
happen that the PCI device goes away before the platform device in which
case the PCI core clears the OF_POPULATED bit. We need to
unconditionally unregister the platform devices for child nodes when
stopping the PCI device.

Fixes: 8fb18619d910 ("PCI/pwrctl: Create platform devices for child OF nodes of the port node")
Signed-off-by: Bartosz Golaszewski <bartosz.golaszewski@...aro.org>
---
 drivers/pci/remove.c | 16 +++++++++++++++-
 1 file changed, 15 insertions(+), 1 deletion(-)

diff --git a/drivers/pci/remove.c b/drivers/pci/remove.c
index 910387e5bdbf..c7092a34a5f6 100644
--- a/drivers/pci/remove.c
+++ b/drivers/pci/remove.c
@@ -1,6 +1,7 @@
 // SPDX-License-Identifier: GPL-2.0
 #include <linux/pci.h>
 #include <linux/module.h>
+#include <linux/of.h>
 #include <linux/of_platform.h>
 #include "pci.h"
 
@@ -16,13 +17,26 @@ static void pci_free_resources(struct pci_dev *dev)
 
 static void pci_stop_dev(struct pci_dev *dev)
 {
+	struct platform_device *pdev;
+
 	pci_pme_active(dev, false);
 
 	if (pci_dev_is_added(dev)) {
-		of_platform_depopulate(&dev->dev);
 		device_release_driver(&dev->dev);
 		pci_proc_detach_device(dev);
 		pci_remove_sysfs_dev_files(dev);
+
+		if (dev_of_node(&dev->dev)) {
+			for_each_child_of_node_scoped(dev_of_node(&dev->dev),
+						      child) {
+				pdev = of_find_device_by_node(child);
+				if (pdev) {
+					of_device_unregister(pdev);
+					of_node_clear_flag(child, OF_POPULATED);
+				}
+			}
+		}
+
 		of_pci_remove_node(dev);
 
 		pci_dev_assign_added(dev, false);
-- 
2.43.0