Red Hat Security Advisory 2012-0358-01 - The kernel packages contain the Linux kernel, the core of any Linux operating system. Using PCI passthrough without interrupt remapping support allowed Xen hypervisor guests to generate MSI interrupts and thus potentially inject traps. A privileged guest user could use this flaw to crash the host or possibly escalate their privileges on the host. The fix for this issue can prevent PCI passthrough working and guests starting.
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