vm-util: Disable UMIP if it is not supported on the host #439
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QEMU emulates UMIP regardless of whether or not it is supported. It does that by trapping every table access, including ltr, which we do on task switch when the I/O permission bitmap changes. This is quite costly in performance, so we disable UMIP if the host does not support it.
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QEMU emulates UMIP regardless of whether or not it is supported. It does that by trapping every table access, including ltr, which we do on task switch when the I/O permission bitmap changes. This is quite costly in performance, so we disable UMIP if the host does not support it.