From mboxrd@z Thu Jan  1 00:00:00 1970
From: Patrick Scharrenberg <pittipatti@web.de>
Subject: out of dma-memory when using usblp-module in
	driverdomain
Date: Sun, 25 Mar 2007 16:29:12 +0200
Message-ID: <46068738.1000802@web.de>
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Hi!

I tried attaching an usb-printer to an usb-port of a driver-domain.
On loading the module usblp I get the following error:

    /usr/src/xen/xen-unstable.hg/linux-2.6.18-xen/drivers/usb/class/usblp.c:
    out of memory for write buf
    usblp: probe of 2-1:1.0 failed with error -5


I figured out, that reducing USBLP_BUF_SIZE (usb/class/usblp.c) form
8192 to some smaller value, e.g. 4096 it works fine, but that's just a
workaround.

USBLP_BUF_SIZE is used to "usb_buffer_alloc" (usb/core/usb.c) dma memory:

>>From usb.c:
     usb_buffer_alloc - allocate dma-consistent buffer for
URB_NO_xxx_DMA_MAP

but here I'm out..


cheers
~patrick