Re: [PATCH 2/2] scsi: Use new __dma_buffer to align sense bufferin scsi_cmnd

[Benjamin Herrenschmidt]

On Fri, 2007-12-21 at 06:16 -0700, Matthew Wilcox wrote:
> On Fri, Dec 21, 2007 at 10:33:26AM +0000, Alan Cox wrote:
> > On Fri, 21 Dec 2007 13:30:08 +1100
> > Benjamin Herrenschmidt <benh@xxxxxxxxxxxxxxxxxxx> wrote:
> > 
> > > The sense buffer ins scsi_cmnd can nowadays be DMA'ed into directly
> > > by some low level drivers (that typically happens with USB mass
> > > storage).
> > 
> > Should that not be fixed in USB storage by using pci_alloc_coherent on the
> > PCI device of the hub not peeing directly into kernel space ?
> 
> That's what I said, but Ben seems fixated on this particular fix.

That means more understanding of the SCSI code than I have right now
and a _lot_ more time than I have right now. It's not only USB storage,
it's anything that does DMA and uses the generic error handling.

Ben.


--
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/