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 From:  Petar Bogdanovic <p+ub at 2005 dot smokva dot net>
 To:  m0n0wall at lists dot m0n0 dot ch
 Subject:  ath0: failed to allocate descriptors: 12
 Date:  Sat, 04 Jun 2005 12:10:51 +0200

I recently tried to convert an old P2 266 MHZ Notebook into a small,
silent & wireless m0n0wall, but I had the following problem with ath(4):

ath0: failed to allocate descriptors: 12
device_attach: ath0 attach returned 12

When I looked around, I found this post on freebsd-stable:


It seems to be the same problem and you can read in the replies, how Sam
Leffler - the man from the MadWIFI-Project - describes the cause of it:

"Memmory is too fragmented to allocate the descriptors in one chunk.  I
changed this logic in current to allocate separate blocks for the
tx+rx+beacon descriptors; I'll look at backporting that (though it's too
risky to get into 5.4)."

Further, there is also a patch of Ian Dowse:

"I've always got it to work with the patch below - I seem to remember
calculating that 32k rather than 256k was all that was needed for
the old descriptor arrangement, but you probably know the real
reason for the larger allocation.


Index: if_ath_pci.c
RCS file: /dump/FreeBSD-CVS/src/sys/dev/ath/if_ath_pci.c,v
retrieving revision
diff -u -r1.8.2.2 if_ath_pci.c
--- if_ath_pci.c	7 Feb 2005 18:01:28 -0000
+++ if_ath_pci.c	19 Mar 2005 20:57:54 -0000
@@ -197,7 +197,7 @@
                     BUS_SPACE_MAXADDR_32BIT,   /* lowaddr */
                     BUS_SPACE_MAXADDR,         /* highaddr */
                     NULL, NULL,                /* filter, filterarg */
-                   0x3ffff,                   /* maxsize XXX */
+                   0x7fff,                    /* maxsize XXX */
                     ATH_MAX_SCATTER,           /* nsegments */
                     0xffff,                    /* maxsegsize XXX */
                     BUS_DMA_ALLOCNOW,          /* flags */"

Is there any chance, to get this patch (or Sams new version in current)
into a beta-version?

With kind regards,