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Message-ID: <48907772.5000801@codemonkey.ws>
Date: Wed, 30 Jul 2008 09:15:14 -0500
From: Anthony Liguori <anthony@codemonkey.ws>
MIME-Version: 1.0
Subject: Re: [Qemu-devel] [PATCH] replacing gettimeofday with clock_gettime
	in hw/serial
References: <489040FF.1070601@eu.citrix.com>
	<200807301428.30863.paul@codesourcery.com>
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To: qemu-devel@nongnu.org
Cc: Stefano Stabellini <stefano.stabellini@eu.citrix.com>

Paul Brook wrote:
> On Wednesday 30 July 2008, Stefano Stabellini wrote:
>   
>> This patch substitutes gettimeofday with clock_gettime in hw/serial.c.
>>
>> gettimeofday is unsafe because can lead to incorrect behaviors if the user
>> changes the system's date.
>>     
>
> This code is just plain wrong to start with.  Devices should not depend on 
> host time.
>   

Because host time continues even when the guest is stopped.  It should 
instead be based on the vm_clock.

I don't think it works either.  I still have gotten messages in the 
guest about too many interrupts on the serial port.

Regards,

Anthony Liguori

> Paul
>
>
>