Re: MSI broken in libata?

From: Tejun Heo
Date: Sun Jan 10 2010 - 21:16:01 EST


Hello, Robert.

On 01/11/2010 10:39 AM, Robert Hancock wrote:
> It'd be interesting to see if it makes a difference, but I don't think
> the patch is quite right. According to the datasheet, doing the MSI ack
> while the interrupt source is still pending will cause a new MSI to be
> sent, so if you do it before handling the interrupt you'll generate a
> spurious interrupt after every real one.

Ah... okay, so the generation of MSI is level triggered? If so, your
original patch is correct. I was thinking it might be edge triggered
and it should be cleared before checking master event mask.

Thanks.

--
tejun
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