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    SubjectRe: [PATCH] do not keep interrupt window closed by sti in real mode
    Glauber Costa wrote:
    >
    > I get the idea from the pseudocode in sti description.
    > It says:
    > IF PE = 0 (* Executing in real-address mode *)
    > THEN
    > IF <- 1; (* Set Interrupt Flag *)
    > ELSE (* Executing in protected mode or virtual-8086 mode *)
    >
    > There is no mention to any other activity besides setting the if flag.

    But the same is true for the protected mode side of the instruction
    description!

    > Also, sti is used extensively in many places like the linux kernel for the
    > guest, and it works just fine in kvm. So I was led to believe that real mode
    > in fact behaving differently.

    The difference is that at least under current Intel VT, VT only handles
    protected mode -- the real mode runs purely in the interpreter.

    > I'll take a look at avi's suggestion.

    -hpa


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