code messed up on B & C chipsets because it lost the packet header
and therefore the flag indicating the need for hardware checksums.
MFC after: 2 weeks
of sf_buf_alloc() instead of expecting sf_buf_alloc()'s caller to map it.
The ultimate reason for this change is to enable two optimizations:
(1) that there never be more than one sf_buf mapping a vm_page at a time
and (2) 64-bit architectures can transparently use their 1-1 virtual
to physical mapping (e.g., "K0SEG") avoiding the overhead of pmap_qenter()
and pmap_qremove().
time a character is written. Use this at boot time to reject the
existing buffer contents if they are corrupt. This fixes a problem
seen on some hardware (especially laptops) where the message buffer
gets partially corrupted during a short power cycle or reset, but
the msgbuf structure is left intact so it gets reused, resulting
in random junk and control characters appearing in dmesg and
/var/log/messages.
PR: kern/28497
the vendor is only included in the long name currently, reducing
verbosity when modules are registered and unregistered.
Obtained from: TrustedBSD Project
Sponsored by: DARPA, Network Associates Laboratories
Quote from kern/37573:
There is an obvious race in netinet/ip_dummynet.c:config_pipe().
Interrupts are not blocked when changing the params of an
existing pipe. The specific crash observed:
... -> config_pipe -> set_fs_parms -> config_red
malloc a new w_q_lookup table but take an interrupt before
intializing it, interrupt handler does:
... -> dummynet_io -> red_drops
red_drops dereferences the uninitialized (zeroed) w_q_lookup
table.
o Flush accumulated credits for idle pipes.
o Flush accumulated credits when change pipe characteristics.
o Change dn_flow_queue.numbytes type to unsigned long.
Overlapping dn_flow_queue->numbytes in ready_event() leads to
numbytes becomes negative and SET_TICKS() macro returns a very
big value. heap_insert() overlaps dn_key again and inserts a
queue to a ready heap with a sched_time points to the past.
That leads to an "infinity" loop.
PR: kern/33234, kern/37573, misc/42459, kern/43133,
kern/44045, kern/48099
Submitted by: Mike Hibler <mike@cs.utah.edu> (kern/37573)
MFC after: 6 weeks
pages which represent actual physical memory we must strip off the fake
page in order to allow illegal aliases to be detected. Otherwise we map
uncacheable in the virtual and physical caches and set the side effect bit,
as is required for mapping device memory.
This fixes gstat on sparc64, which wants to mmap kernel memory through a
character device.
that the feature can be enabled during the boot process. Note the
continued limitation that FreeBSD fails so rapidly with this setting
enabled that it's hard to narrow down particular failures for
correction; we really need per-malloc type failure rates.
flag (M_DONTWAIT / M_TRYWAIT) to a malloc(9) blocking disposition flag
(M_NOWAIT, M_WAITOK). The semantic match isn't perfect, but for
scenarios where malloc data is used in the network stack, such as for
MAC labeling or for m_tags, we sometimes need to map from one to the
other to get the right blocking behavior.
Obtained from: TrustedBSD Project
Sponsored by: DARPA, Network Associates Laboratories
in a debugging feature causing M_NOWAIT allocations to fail at
a specified rate. This can be useful for detecting poor
handling of M_NOWAIT: the most frequent problems I've bumped
into are unconditional deference of the pointer even though
it's NULL, and hangs as a result of a lost event where memory
for the event couldn't be allocated. Two sysctls are added:
debug.malloc.failure_rate
How often to generate a failure: if set to 0 (default), this
feature is disabled. Otherwise, the frequency of failures --
I've been using 10 (one in ten mallocs fails), but other
popular settings might be much lower or much higher.
debug.malloc.failure_count
Number of times a coerced malloc failure has occurred as a
result of this feature. Useful for tracking what might have
happened and whether failures are being generated.
Useful possible additions: tying failure rate to malloc type,
printfs indicating the thread that experienced the coerced
failure.
Reviewed by: jeffr, jhb
This keeps the logical cpu's halted in the idle loop. By default
the logical cpu's are halted at startup. It is also possible to
halt any cpu in the idle loop now using machdep.hlt_cpus.
Examples of how to use this:
machdep.hlt_cpus=1 halt cpu0
machdep.hlt_cpus=2 halt cpu1
machdep.hlt_cpus=4 halt cpu2
machdep.hlt_cpus=3 halt cpu0,cpu1
Reviewed by: jhb, peter
1) Its critical for HTT. There's less foot-shooting opportunity.
2) I've seen significant improvements in interactive response to commands
over ssh sessions. I assume this is less lock contention.
3) As incentive to finish the idle cpu IPI wakeup stuff.
4) The machine on my desk was blowing hot air in my general direction
because somebody forgot to turn the hlt on, and it saves 50 watts per
cpu..
The machdep.cpu_idle_hlt sysctl is still available, but now the default
is the same as on UP kernels.
opening the POSIX fifo; convert ENXIO error returns to EOPNOTSUPP.
This improves handling of the case where the /var/run/lock fifo exists
but there is no listener: we immediately return EOPNOTSUPP rather
than blocking until a listener turns up. This could occur during a
diskless boot before rpc.lockd is loaded, or if the lock file persists
across a reboot following the disabling of rpc.lockd. This may have
suddenly started to occur due to fifo blocking fixes--previously it
looks like attempts to read on a fifo with no listener would time out
due to insufficient resources.
Reviewed by: alfred
