a local 'semid' variable which was the array index and used uap->semid
as the original IPC id. During the kern_semctl() conversion those two
variables were collapsed into a single 'semid' variable breaking the
places that needed the original IPC ID. To fix, add a new 'semidx'
variable to hold the array index and leave 'semid' unmolested as the IPC
id. While I'm here, explicitly document that the (undocumented, at least
in semctl(2)) SEM_STAT command curiously expects an array index in the
'semid' parameter rather than an IPC id.
Submitted by: maxim
to a copied-in copy of the 'union semun' and a uioseg to indicate which
memory space the 'buf' pointer of the union points to. This is then used
in linux_semctl() and svr4_sys_semctl() to eliminate use of the stackgap.
- Mark linux_ipc() and svr4_sys_semsys() MPSAFE.
from going away. mount(2) is now MPSAFE.
- Expand the scope of Giant some in unmount(2) to protect the mp structure
(or rather, to handle concurrent unmount races) from going away.
umount(2) is now MPSAFE, as well as linux_umount() and linux_oldumount().
- nmount(2) and linux_mount() were already MPSAFE.
- For privileged processes safe two mutex operations.
We may want to consider if this is good idea to use SUSER_ALLOWJAIL here,
but for now I didn't wanted to change the original behaviour.
Reviewed by: rwatson
all of the module event handlers are MP safe yet, so always acquire Giant
for now when invoking module event handlers. Eventually we can add an
MPSAFE flag or some such and add appropriate locking to all module event
handlers.
in 1999, and there are changes to the sysctl names compared to PR,
according to that discussion. The description is in sys/conf/NOTES.
Lines in the GENERIC files are added in commented-out form.
I'll attach the test script I've used to PR.
PR: kern/14584
Submitted by: babkin
protect all linker-related data structures including the contents of
linker file objects and the any linker class data as well. Considering how
rarely the linker is used I just went with the simple solution of
single-threading the whole thing rather than expending a lot of effor on
something more fine-grained and complex. Giant is still explicitly
acquired while registering and deregistering sysctl's as well as in the
elf linker class while calling kmupetext(). The rest of the linker runs
without Giant unless it has to acquire Giant while loading files from a
non-MPSAFE filesystem.
- Add a new function linker_release_module() as a more intuitive complement
to linker_reference_module() that wraps linker_file_unload().
linker_release_module() can either take the module name and version info
passed to linker_reference_module() or it can accept the linker file
object returned by linker_reference_module().
file objects calling a user-specified predicate function on each object.
The iteration terminates either when the entire list has been iterated
over or the predicate function returns a non-zero value.
linker_file_foreach() returns the value returned by the last invocation
of the predicate function. It also accepts a void * context pointer that
is passed to the predicate function as well. Using an iterator function
avoids exposing linker internals to the rest of the kernel making locking
simpler.
- Use linker_file_foreach() instead of walking the list of linker files
manually to lookup ndis files in ndis(4).
- Use linker_file_foreach() to implement linker_hwpmc_list_objects().
in setsockopt so that they can be compared correctly against negative
values. Passing in a negative value had a rather negative effect
on our socket code, making it impossible to open new sockets.
PR: 98858
Submitted by: James.Juran@baesystems.com
MFC after: 1 week
It is similar to debug.kdb.trap, except for it tries to cause a page fault
via a call to an invalid pointer. This can highlight differences between
a fault on data access vs. a fault on code call some CPUs might have.
This appeared as a test for a work \
Sponsored by: RiNet (Cronyx Plus LLC)
basically always violated) invariannts of soreceive(), which assume
that the first mbuf pointer in a receive socket buffer can't change
while the SB_LOCK sleepable lock is held on the socket buffer,
which is precisely what these functions do. No current protocols
invoke these functions, and removing them will help discourage them
from ever being used. I should have removed them years ago, but
lost track of it.
MFC after: 1 week
Prodded almost by accident by: peter
frequency, quality and current value of each available time counter.
At the moment all of these are read-only, but it might make sense to
make some of these read-write in the future.
MFC after: 3 months
filesystem agnostic. We are not touching any file system specific functions
in this code path. Since we have a cache lock, there is really no need to
keep Giant around here.
This eliminates Giant acquisitions for any syscall which is auditing pathnames.
Discussed with: jeff
yield() and sched_yield() syscalls. Every scheduler has its own way
to relinquish cpu, the ULE and CORE schedulers have two internal run-
queues, a timesharing thread which calls yield() syscall should be
moved to inactive queue.
KASSERT(ke->ke_runq == NULL) panic when the sched_add is recursively
called by maybe_preempt.
Reported by: Wojciech A. Koszek < dunstan at freebsd dot czest dot pl >
