Re: [PATCH uq/master] kvm: i8254: Fix conversion of in-kernel to userspace state

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On 06/06/2012 05:28 PM, Jan Kiszka wrote:
> Due to a offset between the clock used to generate the in-kernel
> count_load_time (CLOCK_MONOTONIC) and the clock used for processing this
> in userspace (vm_clock), reading back the output of PIT channel 2 via
> port 0x61 was broken. One use cases that suffered from it was the CPU
> frequency calibration of SeaBIOS, which also affected IDE/AHCI timeouts.
> 
> This fixes it by calibrating the offset between both clocks on
> kvm_pit_get and adjusting the kernel value before saving it in the
> userspace state. As the calibration only works while the vm_clock is
> running, we cache the in-kernel state across stopped phases.

Applied, thanks.

> +    clock_offset = LLONG_MAX;

INT64_MAX would me more strictly correct, but in practice it makes no
difference.

-- 
error compiling committee.c: too many arguments to function
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