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From: Benjamin Herrenschmidt <benh@kernel.crashing.org>
Date: Fri, 26 Jul 2013 20:10:48 +1000
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Subject: Re: [Qemu-devel] [PATCH v3] hcd-ohci: add dma error handling
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To: Gerd Hoffmann <kraxel@redhat.com>
Cc: Alexey Kardashevskiy <aik@ozlabs.ru>, Anthony Liguori <aliguori@us.ibm.com>, qemu-devel@nongnu.org

On Fri, 2013-07-26 at 11:58 +0200, Gerd Hoffmann wrote:
> On 07/26/13 11:10, Alexey Kardashevskiy wrote:
> > Current hcd-ohci does not handle DMA errors. However they may happen
> > so here we introduce simple error handling.
> > 
> > On such errors, a typical OHCI will stop operating, signal the guest
> > about the error by sending "UnrecoverableError Event", set itself into
> > error state and set "Detected Parity Error" in its PCI config space
> > to signal that it got an error and so does the patch.
> > 
> > This also adds ohci_stop() call to ohci_bus_start() to handle possible
> > failure of qemu_new_timer_ns().
> > 
> > Signed-off-by: Alexey Kardashevskiy <aik@ozlabs.ru>
> 
> Looks sane to me now.  When I get an ack from Benjamin I'll go put it
> into the usb patch queue.

>>From me ? Heh, I barely remember what the code looks like in there, if
you are both happy with it I don't think you need me :-)

The only possibly comment is that I would have called ohci_stop() something
a bit clearer such as ohci_die() or ohci_buserror() ... IE. That function
does more than just "stop", it also signals an error, and that attribute
should probably be described by the function name.

Cheers,
Ben.