(author's explaination):
Bit 15 is the flag to request a transmit complete interrupt. The
driver was apparently written to minimize interrupts, and if not for a
3-COM design quirk, everything would be just ducky.
Prior to loading the outbound packet into the FIFO, the driver checks
to see if there's enough space to contain the packet. If not, the
driver requests a transmit-available interrupt when there is
sufficient room. Unfortunately, the card is continuing to process the
prior FIFO, and by the time the driver sets the threshold for a
transmit available interrupt, the space is already available. When
this occurs, the 3COM card ignores the interrupt request, and the
driver is hung waiting for an interrupt that will never occur.
There's probably a more elegant solution, but requesting the transmit
complete interrupt was the easiest to implement. An alternative fix
might be to check free FIFO space again, after requesting the transmit
available interrupt, but I haven't bothered pursuing this. Since the
patch, my 3C590 (PCI, same FIFO interface as 3C509) has been rock
solid.
Submitted by: mevans@candle.com (Mike Evans)
pulled up already. This bug can cause the first packet from a source
to a group to be corrupted when it is delivered to a process listening
on the mrouter.
2.1.5-RELEASE). This will obviously be set "for real" closer to the time.
(some ports use this to differentiate the two branches /dev/kmem kernel
architectures. This exact same procedure happened in November last year
for the 2.1 RELEASE as well.)
Fixed initialization of pipe_pgid - don't default to pid 0 (swapper) for
SIGIO.
Added comments about other implicit initializations, mostly for struct
stat.
Fixed initialization of st_mode. S_IFSOCK was for when pipes were sockets.
It is probably safe to fix the bogus S_ISFIFO() now that pipes can be
distinguished from sockets in all cases.
Don't return ENOSYS for inappropriate ioctls.
for big positive adjustments. The existence of big adjustments may
be a bug (it's not documented...) but there was no good reason for
the asymmetric behaviour.
Reviewed by: wollman
is only appropriate to use in the special environment of start.S (real
mode plus some conventions about not saving registers), and asm.h is
supposed to be for generic macros.
Removed some unnecessary parentheses.
Finished the constant poisoning that was begun in rev.1.14. Consts
aren't very poisonous (or useful) unless -Wcast-qual is in CFLAGS,
and it isn't in the default CFLAGS.
Obtained from: Christos Zoulas <christos@deshaw.com> via NetBSD PR 2621,
[ slightly modified since we don't use libcompat anymore. ]
I'm not sure if this fixes the rdist security bug completely, but it
sure can't hurt!
pr_usrreq mechanism which was poorly designed and error-prone. This
commit renames pr_usrreq to pr_ousrreq so that old code which depended on it
would break in an obvious manner. This commit also implements the new
interface for TCP, although the old function is left as an example
(#ifdef'ed out). This commit ALSO fixes a longstanding bug in the
TCP timer processing (introduced by davidg on 1995/04/12) which caused
timer processing on a TCB to always stop after a single timer had
expired (because it misinterpreted the return value from tcp_usrreq()
to indicate that the TCB had been deleted). Finally, some code
related to polling has been deleted from if.c because it is not
relevant t -current and doesn't look at all like my current code.
