Re: [PATCH FIXED] x86: only enable interrupts when kernel statehas been set up

From: Ingo Molnar
Date: Tue Mar 25 2008 - 06:56:20 EST



* Jeremy Fitzhardinge <jeremy@xxxxxxxx> wrote:

> The sysenter path tries to enable interrupts immediately.
> Unfortunately this doesn't work in a paravirt environment, because not
> enough kernel state has been set up at that point (namely, pointing
> %fs to the kernel percpu data segment). To fix this, defer
> ENABLE_INTERRUPTS until after the kernel state has been set up.
>
> Unfortunately this means that we're running with interrupts disabled
> for a while without calling the IRQ tracing code, but that can't be
> called without setting up %fs either.
>
> [ Fix since last posting: make sure saved eflags has interrupts
> enabled. ]

thanks Jeremy - will give it a shot.

Ingo
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