xhci: Fix leaking USB3 shared_hcd at xhci removal

Ensure that the shared_hcd pointer is valid when calling usb_put_hcd()

The shared_hcd is removed and freed in xhci by first calling
usb_remove_hcd(xhci->shared_hcd), and later
usb_put_hcd(xhci->shared_hcd)

Afer commit fe190ed0d602 ("xhci: Do not halt the host until both HCD have
disconnected their devices.") the shared_hcd was never properly put as
xhci->shared_hcd was set to NULL before usb_put_hcd(xhci->shared_hcd) was
called.

shared_hcd (USB3) is removed before primary hcd (USB2).
While removing the primary hcd we might need to handle xhci interrupts
to cleanly remove last USB2 devices, therefore we need to set
xhci->shared_hcd to NULL before removing the primary hcd to let xhci
interrupt handler know shared_hcd is no longer available.

xhci-plat.c, xhci-histb.c and xhci-mtk first create both their hcd's before
adding them. so to keep the correct reverse removal order use a temporary
shared_hcd variable for them.
For more details see commit 4ac53087d6d4 ("usb: xhci: plat: Create both
HCDs before adding them")

Fixes: fe190ed0d602 ("xhci: Do not halt the host until both HCD have disconnected their devices.")
Cc: Joel Stanley <joel@jms.id.au>
Cc: Chunfeng Yun <chunfeng.yun@mediatek.com>
Cc: Thierry Reding <treding@nvidia.com>
Cc: Jianguo Sun <sunjianguo1@huawei.com>
Cc: <stable@vger.kernel.org>
Reported-by: Jack Pham <jackp@codeaurora.org>
Tested-by: Jack Pham <jackp@codeaurora.org>
Tested-by: Peter Chen <peter.chen@nxp.com>
Signed-off-by: Mathias Nyman <mathias.nyman@linux.intel.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

diff --git a/drivers/usb/host/xhci-histb.c b/drivers/usb/host/xhci-histb.c
index 27f00160332e2186327da464d7be327d82bc3170..3c4abb5a1c3fc6bdb86e749ab62cf256381c1f75 100644 (file)
--- a/drivers/usb/host/xhci-histb.c
+++ b/drivers/usb/host/xhci-histb.c
@@ -325,14 +325,16 @@ static int xhci_histb_remove(struct platform_device *dev)
        struct xhci_hcd_histb *histb = platform_get_drvdata(dev);
        struct usb_hcd *hcd = histb->hcd;
        struct xhci_hcd *xhci = hcd_to_xhci(hcd);
+       struct usb_hcd *shared_hcd = xhci->shared_hcd;
 
        xhci->xhc_state |= XHCI_STATE_REMOVING;
 
-       usb_remove_hcd(xhci->shared_hcd);
+       usb_remove_hcd(shared_hcd);
+       xhci->shared_hcd = NULL;
        device_wakeup_disable(&dev->dev);
 
        usb_remove_hcd(hcd);
-       usb_put_hcd(xhci->shared_hcd);
+       usb_put_hcd(shared_hcd);
 
        xhci_histb_host_disable(histb);
        usb_put_hcd(hcd);

diff --git a/drivers/usb/host/xhci-mtk.c b/drivers/usb/host/xhci-mtk.c
index 71d0d33c3286254b0327646720161df6ba5cc1e9..60987c787e44f457d918659140a0671ed7a717e8 100644 (file)
--- a/drivers/usb/host/xhci-mtk.c
+++ b/drivers/usb/host/xhci-mtk.c
@@ -590,12 +590,14 @@ static int xhci_mtk_remove(struct platform_device *dev)
        struct xhci_hcd_mtk *mtk = platform_get_drvdata(dev);
        struct usb_hcd  *hcd = mtk->hcd;
        struct xhci_hcd *xhci = hcd_to_xhci(hcd);
+       struct usb_hcd  *shared_hcd = xhci->shared_hcd;
 
-       usb_remove_hcd(xhci->shared_hcd);
+       usb_remove_hcd(shared_hcd);
+       xhci->shared_hcd = NULL;
        device_init_wakeup(&dev->dev, false);
 
        usb_remove_hcd(hcd);
-       usb_put_hcd(xhci->shared_hcd);
+       usb_put_hcd(shared_hcd);
        usb_put_hcd(hcd);
        xhci_mtk_sch_exit(mtk);
        xhci_mtk_clks_disable(mtk);

diff --git a/drivers/usb/host/xhci-pci.c b/drivers/usb/host/xhci-pci.c
index 01c57055c0c5bf6b85b8fd45ce2d09c1a0ad3d15..1fb448cd26678c9fdde49341b6744025b0966f25 100644 (file)
--- a/drivers/usb/host/xhci-pci.c
+++ b/drivers/usb/host/xhci-pci.c
@@ -380,6 +380,7 @@ static void xhci_pci_remove(struct pci_dev *dev)
        if (xhci->shared_hcd) {
                usb_remove_hcd(xhci->shared_hcd);
                usb_put_hcd(xhci->shared_hcd);
+               xhci->shared_hcd = NULL;
        }
 
        /* Workaround for spurious wakeups at shutdown with HSW */

diff --git a/drivers/usb/host/xhci-plat.c b/drivers/usb/host/xhci-plat.c
index 32b5574ad5c56403eb876a70b492f88182096903..ef09cb06212fd367da3593092a31dd5c32d95f58 100644 (file)
--- a/drivers/usb/host/xhci-plat.c
+++ b/drivers/usb/host/xhci-plat.c
@@ -362,14 +362,16 @@ static int xhci_plat_remove(struct platform_device *dev)
        struct xhci_hcd *xhci = hcd_to_xhci(hcd);
        struct clk *clk = xhci->clk;
        struct clk *reg_clk = xhci->reg_clk;
+       struct usb_hcd *shared_hcd = xhci->shared_hcd;
 
        xhci->xhc_state |= XHCI_STATE_REMOVING;
 
-       usb_remove_hcd(xhci->shared_hcd);
+       usb_remove_hcd(shared_hcd);
+       xhci->shared_hcd = NULL;
        usb_phy_shutdown(hcd->usb_phy);
 
        usb_remove_hcd(hcd);
-       usb_put_hcd(xhci->shared_hcd);
+       usb_put_hcd(shared_hcd);
 
        clk_disable_unprepare(clk);
        clk_disable_unprepare(reg_clk);

diff --git a/drivers/usb/host/xhci-tegra.c b/drivers/usb/host/xhci-tegra.c
index 6b5db344de3011df7154f698333e97c5f62f8f69..938ff06c034959f445dc8ad764d2e8a97887c15b 100644 (file)
--- a/drivers/usb/host/xhci-tegra.c
+++ b/drivers/usb/host/xhci-tegra.c
@@ -1303,6 +1303,7 @@ static int tegra_xusb_remove(struct platform_device *pdev)
 
        usb_remove_hcd(xhci->shared_hcd);
        usb_put_hcd(xhci->shared_hcd);
+       xhci->shared_hcd = NULL;
        usb_remove_hcd(tegra->hcd);
        usb_put_hcd(tegra->hcd);
 

diff --git a/drivers/usb/host/xhci.c b/drivers/usb/host/xhci.c
index 0420eefa647a15cb5321dfa5fd95556a5a5432e5..c928dbbff8811206fd3f668564b3ffe627cdd2aa 100644 (file)
--- a/drivers/usb/host/xhci.c
+++ b/drivers/usb/host/xhci.c
@@ -719,8 +719,6 @@ static void xhci_stop(struct usb_hcd *hcd)
 
        /* Only halt host and free memory after both hcds are removed */
        if (!usb_hcd_is_primary_hcd(hcd)) {
-               /* usb core will free this hcd shortly, unset pointer */
-               xhci->shared_hcd = NULL;
                mutex_unlock(&xhci->mutex);
                return;
        }