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    virtio_pci: Prevent double-free of pci regions after device hot-unplug · 31a3ddda
    Amit Shah 提交于
    In the case where a virtio-console port is in use (opened by a program)
    and a virtio-console device is removed, the port is kept around but all
    the virtio-related state is assumed to be gone.
    
    When the port is finally released (close() called), we call
    device_destroy() on the port's device.  This results in the parent
    device's structures to be freed as well.  This includes the PCI regions
    for the virtio-console PCI device.
    
    Once this is done, however, virtio_pci_release_dev() kicks in, as the
    last ref to the virtio device is now gone, and attempts to do
    
         pci_iounmap(pci_dev, vp_dev->ioaddr);
         pci_release_regions(pci_dev);
         pci_disable_device(pci_dev);
    
    which results in a double-free warning.
    
    Move the code that releases regions, etc., to the virtio_pci_remove()
    function, and all that's now left in release_dev is the final freeing of
    the vp_dev.
    Signed-off-by: NAmit Shah <amit.shah@redhat.com>
    Signed-off-by: NRusty Russell <rusty@rustcorp.com.au>
    31a3ddda
virtio_pci.c 19.1 KB