Re: VMI Interface Proposal Documentation for I386, Part 4
From: Pavel Machek
Date: Wed Mar 15 2006 - 18:34:36 EST
Hi!
> 6) Interrupts must always be enabled when running code in userspace.
I'd say this breaks userspace.
This code used to work when ran as root:
void
main(void)
{
int i;
iopl(3);
while (1) {
asm volatile("cli");
// for (i=0; i<20000000; i++)
for (i=0; i<1000000000; i++)
asm volatile("");
asm volatile("sti");
sleep(1);
}
}
...and was actually useful.
> 7) IOPL semantics for userspace are changed; although userspace may be
> granted port access, it can not affect the interrupt flag.
I'm not sure how will X like this.
Pavel
--
57: MD5CryptoServiceProvider MD5 = new MD5CryptoServiceProvider();
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