• Mathias Nyman's avatar
    xhci: Fix leaking USB3 shared_hcd at xhci removal · f0680904
    Mathias Nyman authored
    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 fe190ed0 ("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 4ac53087 ("usb: xhci: plat: Create both
    HCDs before adding them")
    
    Fixes: fe190ed0 ("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: default avatarJack Pham <jackp@codeaurora.org>
    Tested-by: default avatarJack Pham <jackp@codeaurora.org>
    Tested-by: default avatarPeter Chen <peter.chen@nxp.com>
    Signed-off-by: default avatarMathias Nyman <mathias.nyman@linux.intel.com>
    Signed-off-by: default avatarGreg Kroah-Hartman <gregkh@linuxfoundation.org>
    f0680904
xhci-histb.c 9.64 KB