I/O requests must be marked P_SYSTEM because if it isn't and the system
decides to swap it or (god forbid) kill it, the system stands a good
chance of locking up.
chip revisions. (A buggy taiwanese chip? I'm just shocked; shocked I tell
you.) So far I have only observed the anomalous behavior on board with
PCI revision 33 chips. At the moment, this seems to include only the
Netgear FA310-TX rev D1 boards with chips labeled NGMC169B. (Possibly this
means it's an 82c169B part from Lite-On.)
The bug only manifests itself in promiscuous mode, and usually only at
10Mbps half-duplex. (I have not observed the problem in full-duplex mode,
and I don't think it ever happens at 100Mbps.) The bug appears to be in
the receiver DMA engine. Normally, the chip is programmed with a linked
list of receiver descriptors, each with a receive buffer capable of holding
a complete full-sized ethernet frame. During periods of heavy traffic
(i.e. ping -c 100 -f 8100 <otherhost>), the receiver will sometimes appear
to upload its entire FIFO memory contents instead of just uploading the
desired received frame. The uploaded data will span several receive
buffers, in spite of the fact that the chip has been told to only use
one descriptor per frame, and appears to consist of previously transmitted
frames with the correct received frame appended to the end.
Unfortunately, there is no way to determine exactly how much data is
uploaded when this happens; the chip doesn't tell you anything except the
size of the desired received frame, and the amount of bogus data varies.
Sometimes, the desired frame is also split across multiple buffers.
The workaround is ugly and nasty. The driver assembles all of the data
from the bogus frames into a single buffer. The receive buffers are always
zeroed out, and we program the chip to always include the receive CRC
at the end of each frame. We therefore know that we can start from the
end of the buffer and scan back until we encounter a non-zero data byte,
and say conclusively that this is the end of the desired frame. We can
then subtract the frame length from this address to determine the real
start of the frame, and copy it into an mbuf and pass it on.
This is kludgy and time consuming, but it's better than dropping frames.
It's not too bad since the problem only happens at 10Mbps.
The workaround is only enabled for chips with PCI revision == 33. The
LinkSys LNE100TX and Matrox FastNIC 10/100 cards use a revision 32 chip
and work fine in promiscuous mode. Netgear support has confirmed that
they "have some previous knowledge of problems in promiscuous mode" but
didn't have a workaround. The people at Lite-On who would be able to
suggest a possible fix are on vacation. So, I decided to implement a
workaround of my own until I hear from them. I suppose this problem made
it through Netgear's QA department since Windows doesn't normally use
promiscuous mode, and if Windows doesn't need the feature than it can't
possibly be important, right? Grrr.
key? ( -- flag) \ check to see if there's a key to be read from input
ms ( u -- ) \ wait that many milliseconds
seconds ( -- u ) \ get number of seconds from midnight.
'words' now outputs the list page by page - this probably should go
through libstand's pager, but will have to wait for closer integration of
built-ins with Forth...
Submitted partially by: W Gerald Hicks <wghicks@bellsouth.net>
this has a problem with capture but i am not sure if it is related
to the mixer or what else.
But in the meantime, this is ok to listen to mpegs.
I also have a much simpler version of the driver in the works which
reuses a lot more of the existing "pcm" routines. Next year...
have all fields in network order, whereas ipfw expects some to be
in host order. This resulted in some incorrect matching, e.g. some
packets being identified as fragments, or bandwidth not being
correctly enforced.
NOTE: this only affects bridge+ipfw, normal ipfw usage was already
correct).
Reported-By: Dave Alden and others.
kernel forced migration happening soon.
While still incomplete, and there may be showstoppers along the way,
the advise given here is not incorrect.
Submitted indirectly by: jdk, peter wemm
Set_Boot_Blocks() anyway and should thus have never been a part of
libdisk, it should have been provided by the client of libdisk since
passing the information in is already part of the API.
-add "depends" to list of recursive targets
-consistent capitilization of FreeBSD.ORG
-remove description of PATCH_DEBUG
-add .Xr to portcheckout(1) and pib(1)
* Move the user stack from VM_MAXUSER_ADDRESS to a place below the 32bit
boundary (needed to support 32bit OSF programs). This should also save
one pagetable per process.
* Add cvtqlsv to the set of instructions handled by the floating point
software completion code.
* Disable all floating point exceptions by default.
* A minor change to execve to allow the OSF1 image activator to support
dynamic loading.
default for BINDIR. The default BINDIR of /usr/mdec can't be overridden
yet because libdisk still uses /usr/mdec and installing in /boot might
clobber the new boot blocks.
Don't install links to bootxx or xxboot.
Install boot1 and boot2 in 1 step.
Don't delete the boot.help source file on installing it when ${COPY} is
null.
