Re: [PATCH for-2.6.35] virtio-pci: disable msi at startup

[Michael S. Tsirkin]

On Wed, Jun 23, 2010 at 05:21:37PM +0300, Avi Kivity wrote:
> On 06/23/2010 04:59 PM, Michael S. Tsirkin wrote:
>>
>>> Why doesn't a device reset result in msi being cleared?
>>>      
>> This is not a standard function reset. This is virtio specific
>> command. So it only clears virtio registers.
>>    
>
> I see.  We should implement FLR in qemu.

We can do this. Or PM reset. however ...

>  If we don't already do so, we  
> should probably FLR anything that moves when a kexec kernel starts.

Probably only whatever we want to use. But whether this will make it
more, or less robust, is an open question.

>>> Shouldn't a reset be equivalent to power cycling?
>>>      
>> If we did this, driver would need to restore registers
>> such as BAR etc.
>>    
>
> We could save/restore the registers we care about.

It seems easier to clear registers we care about.  It's also too late
now: changing behaviour will break old drivers.

> -- 
> error compiling committee.c: too many arguments to function
--
To unsubscribe from this list: send the line "unsubscribe linux-kernel" in
the body of a message to majordomo@xxxxxxxxxxxxxxx
More majordomo info at  http://vger.kernel.org/majordomo-info.html
Please read the FAQ at  http://www.tux.org/lkml/