linux-kernel - [PATCH] usb: xhci: tegra: Add shutdown callback for Tegra XUSB

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-next>] [day] [month] [year] [list]

Message-ID: <20230718072057.233011-1-haotienh@nvidia.com>
Date:   Tue, 18 Jul 2023 15:20:57 +0800
From:   Haotien Hsu <haotienh@...dia.com>
To:     Mathias Nyman <mathias.nyman@...el.com>,
        Greg Kroah-Hartman <gregkh@...uxfoundation.org>,
        Thierry Reding <thierry.reding@...il.com>,
        Jonathan Hunter <jonathanh@...dia.com>,
        <inux-usb@...r.kernel.org>, <linux-tegra@...r.kernel.org>,
        <linux-kernel@...r.kernel.org>
CC:     Wayne Chang <waynec@...dia.com>, JC Kuo <jckuo@...dia.com>,
        WK Tsai <wtsai@...dia.com>, Henry Lin <henryl@...dia.com>,
        Haotien Hsu <haotienh@...dia.com>
Subject: [PATCH] usb: xhci: tegra: Add shutdown callback for Tegra XUSB

From: Henry Lin <henryl@...dia.com>

If memory accesses by the Tegra XUSB controller are translated through
the SMMU (System MMU), the hardware may continue accessing memory even
after the SMMU translations have been disabled during the shutdown
process and this can in turn cause unpredictable crashes.
Fix this by adding a shutdown implementation that ensures the hardware
is turned off during system reboot or shutdown.

Signed-off-by: Henry Lin <henryl@...dia.com>
Signed-off-by: Haotien Hsu <haotienh@...dia.com>
---
 drivers/usb/host/xhci-tegra.c | 28 +++++++++++++++++++++-------
 1 file changed, 21 insertions(+), 7 deletions(-)

diff --git a/drivers/usb/host/xhci-tegra.c b/drivers/usb/host/xhci-tegra.c
index a56cc81b9404..6ef2eac9835d 100644
--- a/drivers/usb/host/xhci-tegra.c
+++ b/drivers/usb/host/xhci-tegra.c
@@ -1925,6 +1925,15 @@ static int tegra_xusb_probe(struct platform_device *pdev)
 	return err;
 }
 
+static void tegra_xusb_disable(struct tegra_xusb *tegra)
+{
+	tegra_xusb_powergate_partitions(tegra);
+	tegra_xusb_powerdomain_remove(tegra->dev, tegra);
+	tegra_xusb_phy_disable(tegra);
+	tegra_xusb_clk_disable(tegra);
+	regulator_bulk_disable(tegra->soc->num_supplies, tegra->supplies);
+}
+
 static int tegra_xusb_remove(struct platform_device *pdev)
 {
 	struct tegra_xusb *tegra = platform_get_drvdata(pdev);
@@ -1947,18 +1956,22 @@ static int tegra_xusb_remove(struct platform_device *pdev)
 
 	pm_runtime_put(&pdev->dev);
 
-	tegra_xusb_powergate_partitions(tegra);
-
-	tegra_xusb_powerdomain_remove(&pdev->dev, tegra);
-
-	tegra_xusb_phy_disable(tegra);
-	tegra_xusb_clk_disable(tegra);
-	regulator_bulk_disable(tegra->soc->num_supplies, tegra->supplies);
+	tegra_xusb_disable(tegra);
 	tegra_xusb_padctl_put(tegra->padctl);
 
 	return 0;
 }
 
+static void tegra_xusb_shutdown(struct platform_device *pdev)
+{
+	struct tegra_xusb *tegra = platform_get_drvdata(pdev);
+
+	pm_runtime_get_sync(&pdev->dev);
+	disable_irq(tegra->xhci_irq);
+	xhci_shutdown(tegra->hcd);
+	tegra_xusb_disable(tegra);
+}
+
 static bool xhci_hub_ports_suspended(struct xhci_hub *hub)
 {
 	struct device *dev = hub->hcd->self.controller;
@@ -2666,6 +2679,7 @@ MODULE_DEVICE_TABLE(of, tegra_xusb_of_match);
 static struct platform_driver tegra_xusb_driver = {
 	.probe = tegra_xusb_probe,
 	.remove = tegra_xusb_remove,
+	.shutdown = tegra_xusb_shutdown,
 	.driver = {
 		.name = "tegra-xusb",
 		.pm = &tegra_xusb_pm_ops,
-- 
2.25.1