Re: [RFT PATCH] ieee1394: ohci1394: serialize reset requests andirq handler

From: Stefan Richter
Date: Fri Jan 26 2007 - 13:40:39 EST


I wrote:
> - Use the ohci->event_lock to serialize the trigger for software-
> enforced bus resets against a large portion of the IRQ handler.
...
> Todo:
> - Test.
> - Audit *all* of ohci1394's register accesses for the need of
> serialization by spinlocks + mmiowb.
...

PS: AFAIU what I'm doing here, it affects

- bus resets triggered by local software (the bug report was also
about externally triggered bus resets),

- and potentially bus resets (even externally triggered ones) on SMP
systems with (PCI) bridges if the IRQ handler migrates to a another
CPU between two interrupt events in quick succession.

Can the latter happen in Linux or/and with -rt kernels?
--
Stefan Richter
-=====-=-=== ---= ==-=-
http://arcgraph.de/sr/
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