Re: Possibly SATA related freeze killed networking and RAID

From: Phillip Susi
Date: Mon Dec 03 2007 - 12:15:31 EST


Tejun Heo wrote:
Surprise, surprise. There's no way to tell whether the controller
raised interrupt or not if command is not in progress. As I said
before, there's no IRQ pending bit. While processing commands, you can
tell by looking at other status registers but when there's nothing in
flight and the controller determines it's a good time to raise a
spurious interrupt, there's no way you can tell. That dang SFF
interface is like 15+ years old.

But we can still make things pretty robust. We're working on it.

Thanks.


It sounds like you mean that you know the controller did NOT raise the interrupt ( intentionally/correctly ) if there was no command in progress, as opposed to not being able to tell. Unless there is some condition under which it is valid for the controller to raise an interrupt when it had no commands in progress? And if that's the case and there's know way to know WHY, that's a broken design.

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