AMD AMD5K86 - Protected Virtual Interrupt (PVI) Extensions

AMDl'
AMD5,IJ6 Processor Technical Reference Manual
18524BjO-Mar1996
3.1.5
1-24
Protected Virtual Interrupt (PVI) Extensions
The Protected Virtual Interrupts (PVI) bit in CR4 enables sup-
port for interrupt virtualization in Protected mode. In this vir-
tualization, the processor maintains program-specific VIF and
VIP flags in a manner similar to those in Virtual-8086 Mode
Extensions (VME). When a program is executed at CPL = 3, it
can set and clear its copy of the VIF flag without causing gen-
eral-protection exceptions.
The only differences between the VME and PVI extensions are
that, in PVI, selective INTn interception using the Interrupt
Redirection Bitmap in the TSS does not apply, and only the STI
and CLI instructions are affected by the extension.
Tables 3-5 and 3-6 show, among other things, the behavior of
hard':Vare and software interrupts, and instructions that affect
interrupts, in Protected mode with the PVI extensions enabled.
Software Environment and Extensions