socket lock around knlist_init(), so don't.
Hard code the setting of the socket reference count to 1 rather than
using soref() to avoid asserting the socket lock, since we've not yet
exposed the socket to other threads.
This removes two mutex operations from each socket allocation.
so that the socket does not generate SIGPIPE, only EPIPE, when a write
is attempted after socket shutdown. When the option was introduced in
2002, this required the logic for determining whether SIGPIPE was
generated to be pushed down from dofilewrite() to the socket layer so
that the socket options could be considered. However, the change in
2002 omitted modification to soo_write() required to add that logic,
resulting in SIGPIPE not being generated even without SO_NOSIGPIPE when
the socket was written to using write() or related generic system calls.
This change adds the EPIPE logic to soo_write(), generating a SIGPIPE
signal to the process associated with the passed uio in the event that
the SO_NOSIGPIPE option is not set.
Notes:
- The are upsides and downsides to placing this logic in the socket
layer as opposed to the file descriptor layer. This is really fd
layer logic, but because we need so_options, we have a choice of
layering violations and pick this one.
- SIGPIPE possibly should be delivered to the thread performing the
write, not the process performing the write.
- uio->uio_td and the td argument to soo_write() might potentially
differ; we use the thread in the uio argument.
- The "sigpipe" regression test in src/tools/regression/sockets/sigpipe
tests for the bug.
Submitted by: Mikko Tyolajarvi <mbsd at pacbell dot net>
Talked with: glebius, alfred
PR: 78478
MFC after: 1 week
SIGPIPE signal for the duration of the sento-family syscalls. Use it to
replace previously added hack in Linux layer based on temporarily setting
SO_NOSIGPIPE flag.
Suggested by: alfred
Add support for passing in a mutex. If NULL is passed a global
subr_unit mutex is used.
Add alloc_unrl() which expects the mutex to be held.
Allocating a unit will never sleep as it does not need to allocate
memory.
Cut possible range in half so we can use -1 to mean "out of number".
Collapse first and last runs into the head by means of counters.
This saves memory in the common case(s).
at some point result in a status event being triggered (it should
be a link down event: the Microsoft driver design guide says you
should generate one when the NIC is initialized). Some drivers
generate the event during MiniportInitialize(), such that by the
time MiniportInitialize() completes, the NIC is ready to go. But
some drivers, in particular the ones for Atheros wireless NICs,
don't generate the event until after a device interrupt occurs
at some point after MiniportInitialize() has completed.
The gotcha is that you have to wait until the link status event
occurs one way or the other before you try to fiddle with any
settings (ssid, channel, etc...). For the drivers that set the
event sycnhronously this isn't a problem, but for the others
we have to pause after calling ndis_init_nic() and wait for the event
to arrive before continuing. Failing to wait can cause big trouble:
on my SMP system, calling ndis_setstate_80211() after ndis_init_nic()
completes, but _before_ the link event arrives, will lock up or
reset the system.
What we do now is check to see if a link event arrived while
ndis_init_nic() was running, and if it didn't we msleep() until
it does.
Along the way, I discovered a few other problems:
- Defered procedure calls run at PASSIVE_LEVEL, not DISPATCH_LEVEL.
ntoskrnl_run_dpc() has been fixed accordingly. (I read the documentation
wrong.)
- Similarly, the NDIS interrupt handler, which is essentially a
DPC, also doesn't need to run at DISPATCH_LEVEL. ndis_intrtask()
has been fixed accordingly.
- MiniportQueryInformation() and MiniportSetInformation() run at
DISPATCH_LEVEL, and each request must complete before another
can be submitted. ndis_get_info() and ndis_set_info() have been
fixed accordingly.
- Turned the sleep lock that guards the NDIS thread job list into
a spin lock. We never do anything with this lock held except manage
the job list (no other locks are held), so it's safe to do this,
and it's possible that ndis_sched() and ndis_unsched() can be
called from DISPATCH_LEVEL, so using a sleep lock here is
semantically incorrect. Also updated subr_witness.c to add the
lock to the order list.
asynchronously by different threads. Thus, declare as volatile the
reference count that is accessed through m_ext's pointer, ref_cnt.
Revert the previous change, revision 1.144, that casts as volatile a
single dereference of ref_cnt.
Reviewed by: bmilekic, dwhite
Problem reported by: kris
MFC after: 3 days
for a signal, because kernel stack is swappable, this causes page fault
in kernel under heavy swapping case. Fix this bug by eliminating unneeded
code.
create kernel threads and call rfork(2) with RFTHREAD flag set in this case,
which puts parent and child into the same threading group. As a result
all threads that belong to the same program end up in the same threading
group.
This is similar to what linuxthreads port does, though in this case we don't
have a luxury of having access to the source code and there is no definite
way to differentiate linux_clone() called for threading purposes from other
uses, so that we have to resort to heuristics.
Allow SIGTHR to be delivered between all processes in the same threading
group previously it has been blocked for s[ug]id processes.
This also should improve locking of the same file descriptor from different
threads in programs running under linux compat layer.
PR: kern/72922
Reported by: Andriy Gapon <avg@icyb.net.ua>
Idea suggested by: rwatson
place.
This moves the dependency on GCC's and other compiler's features into
the central sys/cdefs.h file, while the individual source files can
then refer to #ifdef __COMPILER_FEATURE_FOO where they by now used to
refer to #if __GNUC__ > 3.1415 && __BARC__ <= 42.
By now, GCC and ICC (the Intel compiler) have been actively tested on
IA32 platforms by netchild. Extension to other compilers is supposed
to be possible, of course.
Submitted by: netchild
Reviewed by: various developers on arch@, some time ago
sleeping, so in do_tdsignal, we no longer need to test td_waitset.
now td_waitset is only used to give a thread higher priority when
delivering signal to multithreads process.
This also fixes a bug:
when a thread in sigwait states was suspended and later resumed
by SIGCONT, it can no longer receive signals belong to waitset.
debug.cpufreq.lowest tunable and sysctl. Some systems seem to have problems
with the lowest frequencies so setting this prevents them from being
available or used.
owned by a process when it forks, and creates a matching set of references
for the child process, as prescribed by POSIX.
In order to avoid races with other threads in the parent process during
fork(), it is necessary to allocate a temporary reference list while
holding the sem_lock, then transfer those references to the new process
once the sem_lock is released. The implementation is inefficient but
appears functional; in order to improve the efficiency, it will be
necessary to modify the existing structures and logic, which generally
rely on O(n) operations over the global set of semaphores.
PAGE_SIZE.
Unlike originator of the PR suggests retain MAXSHELLCMDLEN definition
(he has been proposing to replace it with PAGE_SIZE everywhere), not only
this reduced the diff significantly, but prevents code obfuscation and also
allows to increase/decrease this parameter easily if needed.
PR: kern/64196
Submitted by: Magnus Bäckström <b@etek.chalmers.se>
doesn't change functionality, but makes code more logical.
Obtained from: DrafonFlyBSD
o Use VOP_GETATTR() to obtain actual size of file and parse no more than that.
Previously, we parsed MAXSHELLCMDLEN characters regardless of the actual file
size. This makes the following working:
$ printf '#!/bin/echo' > /tmp/test.sh
$ chmod 755 /tmp/test.sh
$ /tmp/test.sh
Previously, attempts to execve() that shell script has been failing with bogus
ENAMETOOLONG.
PR: kern/64196
Submitted by: Magnus B.ckstr.m <b@etek.chalmers.se>
script. Otherwise it's possible to panic kernel by constructing a shell
script with first line not ending in '\n'.
Also, treat '\0' as line terminating character, which may me useful in
some situations.
Submitted by: gad
