Re: invalidate caches before going into suspend

From: H. Peter Anvin
Date: Wed Aug 13 2008 - 12:54:25 EST


Ingo Molnar wrote:

also, we might be safer if the wbinvd(), the CLI and the halt was in a single assembly sequence:

if (cpu >= i486)
asm ("cli; wbinvd; cli; 1: hlt; jmp 1b")
else
asm ("cli; 1: hlt; jmp 1b")

to make sure the compiler doesnt ever insert something into this codepath? [ And note the double cli which would be further robustification - in theory we could get a spurious interrupt straight after the wbinvd. ] Hm?


Spurious interrupt of what kind? The only things that could come in would not be non-INT type interrupts, and those aren't affected by CLI.

-hpa
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