Re: [Qemu-devel] Question about qemu firmware configuration (fw_cfg) device

[Richard W.M. Jones]

On Mon, Jul 19, 2010 at 12:19:22PM +0300, Gleb Natapov wrote:
> Vcpu executes "in %ax". Next instruction is executed 6 seconds later.
> All timers that should have been processed during this time fire at the
> same moment triggering all kind of timeouts. Think about watchdog that
> should be written into every two seconds otherwise it does reset.

This particular code runs very early in boot, and the atomic copy
operation is very quick even with a 100MB initrd.

But the question I think should be: If a guest maliciously (after
boot) tried to use this mechanism, could it do harm to the host?  Or
would it just harm itself?

Rich.

-- 
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