On Wed, 18 Sep, at 07:28:53PM, Bart Kuivenhoven wrote: > The problem in efi_main was that the idt was cleared before the > interrupts were disabled. > > The UEFI spec states that interrupts aren't used so this shouldn't be > too much of a problem. Peripherals however don't necessarily know about > this and thus might cause interrupts to happen anyway. Even if > ExitBootServices() has been called. > > This means there is a risk of an interrupt being triggered while the IDT > register is nullified and the interrupt bit hasn't been cleared, > allowing for a triple fault. Just to be clear, you haven't witnessed a triple fault, correct? > This patch fixes this by clearing the interrupt bit before the lidt > instruction. I think we can go even further than this and get rid of all of the IDT code in the EFI boot stub. The kernel maintains its own IDT anyway. -- Matt Fleming, Intel Open Source Technology Center -- To unsubscribe from this list: send the line "unsubscribe linux-efi" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html
