In the Linux kernel, the following vulnerability has been resolved: iommu/amd: Fix pci device refcount leak in ppr_notifier() As comment of pci_get_domain_bus_and_slot() says, it returns a pci device with refcount increment, when finish using it, the caller must decrement the reference count by calling pci_dev_put(). So call it before returning from ppr_notifier() to avoid refcount leak.
https://git.kernel.org/stable/c/efd50c65fd1cdef63eb58825f3fe72496443764c
https://git.kernel.org/stable/c/bdb2113dd8f17a3cc84a2b4be4968a849f69ec72
https://git.kernel.org/stable/c/b0637f4bd426925f5c3a15e8f8e36190fe06bac5
https://git.kernel.org/stable/c/902cc2507091a81643502d8ceb0e2f105e902518
https://git.kernel.org/stable/c/8581ec1feb895ff596fe3d326d9ba320083290aa
https://git.kernel.org/stable/c/6e501b3fd7a2e1c4372d72bc70717aaca2beb8a5
https://git.kernel.org/stable/c/6cf0981c2233f97d56938d9d61845383d6eb227c
https://git.kernel.org/stable/c/03f51c72997559e73b327608f0cccfded715c9a0