Just in case of uninitialized padding which would lead to kernel
stack disclosure. If the compiler can prove the memset redundant
then it can optimize it away; otherwise better safe than sorry.
For linux_sys_sched_setaffinity, pid == 0 means the current thread.
On the other hand, for our native sys_sched_setaffinity, lid == 0
means all lwp's that belong to the process.
own LWP ID space, LWP IDs came from the same number space as PIDs. The
lead LWP of a process gets the PID as its LID. If a multi-LWP process's
lead LWP exits, the PID persists for the process.
In addition to providing system-wide unique thread IDs, this also lets us
eliminate the per-process LWP radix tree, and some associated locks.
Remove the separate "global thread ID" map added previously; it is no longer
needed to provide this functionality.
Nudged in this direction by ad@ and chs@.
when allocating a PID.
- Per above, proc_free_pid() no longer decrements nprocs. It's now done
in proc_free() right after proc_free_pid().
- Ensure nprocs is accessed using atomics everywhere.
- Adapt to cpu_need_resched() changes. Avoid lost & duplicate IPIs and ASTs.
sched_resched_cpu() and sched_resched_lwp() contain the logic for this.
- Changes for LSIDL to make the locking scheme match the intended design.
- Reduce lock contention and false sharing further.
- Numerous small bugfixes, including some corrections for SCHED_FIFO/RT.
- Use setrunnable() in more places, and merge cut & pasted code.
Synchromize the struct field format with other BSDs and Darwin.
No ABI change between older and newer struct form on the ports.
The change will require no changes to most C users during the transition
period as the header keeps a caller cast.
Discussed with core@ and there were no objections for this move.
After refactoring by <chs> in 2010 (r. 1.63) the p variable is no longer
used.
As noted by <Mateusz Guzik> its usage is also unsafe and might cause
use-after-free scenarios.
No functional change intended.
Reference: http://mail-index.netbsd.org/tech-kern/2017/09/08/msg022267.html
Sponsored by <The NetBSD Foundation>
- update the linux syscall table for each platform.
- support new-style (NPTL) linux pthreads on all platforms.
clone() with CLONE_THREAD uses 1 process with many LWPs
instead of separate processes.
- move the contents of sys__lwp_setprivate() into a new
lwp_setprivate() and use that everywhere.
- update linux_release[] and linux32_release[] to "2.6.18".
- adjust placement of emul fork/exec/exit hooks as needed
and adjust other emul code to match.
- convert all struct emul definitions to use named initializers.
- change the pid allocator to allow multiple pids to refer to the same proc.
- remove a few fields from struct proc that are no longer needed.
- disable the non-functional "vdso" code in linux32/amd64,
glibc works fine without it.
- fix a race in the futex code where we could miss a wakeup after
a requeue operation.
- redo futex locking to be a little more efficient.
Rename real routines to proc_find() and pgrp_find(), remove PFIND_* flags
and have consistent behaviour. Provide proc_find_raw() for special cases.
Fix memory leak in sysctl_proc_corename().
COMPAT_LINUX: rework ptrace() locking, minimise differences between
different versions per-arch.
Note: while this change adds some formal cosmetics for COMPAT_DARWIN and
COMPAT_IRIX - locking there is utterly broken (for ages).
Fixes PR/43176.
proclist_mutex and proclist_lock into a single adaptive mutex (proc_lock).
Implications:
- Inspecting process state requires thread context, so signals can no longer
be sent from a hardware interrupt handler. Signal activity must be
deferred to a soft interrupt or kthread.
- As the proc state locking is simplified, it's now safe to take exit()
and wait() out from under kernel_lock.
- The system spends less time at IPL_SCHED, and there is less lock activity.
Make the FreeBSD and Linux compat code convert the parameters to their
native representation and call the native routines.
Remove KAUTH_PROCESS_SCHEDULER_GET/SET.
Update documentation and examples.
XXX: For now, only the Linux compat code does the priority conversion
XXX: right.
Linux priority conversion code from yamt@, thanks!
Okay yamt@.
words, don't pass an action and a request, and just use a single action to
indicate what is the operation in question.
This is the first step in fixing PR/37986, which calls for policy/priority
checking in the secmodel code. Right now we're lacking room for another
parameter required to make a decision, and this change makes room for such.
- Add a KAUTH_PROCESS_SCHEDULER action, to handle scheduler related
requests, and add specific requests for set/get scheduler policy and
set/get scheduler parameters.
- Add a KAUTH_PROCESS_KEVENT_FILTER action, to handle kevent(2) related
requests.
- Add a KAUTH_DEVICE_TTY_STI action to handle requests to TIOCSTI.
- Add requests for the KAUTH_PROCESS_CANSEE action, indicating what
process information is being looked at (entry itself, args, env,
open files).
- Add requests for the KAUTH_PROCESS_RLIMIT action indicating set/get.
- Add requests for the KAUTH_PROCESS_CORENAME action indicating set/get.
- Make bsd44 secmodel code handle the newly added rqeuests appropriately.
All of the above make it possible to issue finer-grained kauth(9) calls in
many places, removing some KAUTH_GENERIC_ISSUSER requests.
- Remove the "CAN" from KAUTH_PROCESS_CAN{KTRACE,PROCFS,PTRACE,SIGNAL}.
Discussed with christos@ and yamt@.
int foo(struct lwp *l, void *v, register_t *retval)
to:
int foo(struct lwp *l, const struct foo_args *uap, register_t *retval)
Fixup compat code to not write into 'uap' and (in some cases) to actually
pass a correctly formatted 'uap' structure with the right name to the
next routine.
A few 'compat' routines that just call standard ones have been deleted.
All the 'compat' code compiles (along with the kernels required to test
build it).
98% done by automated scripts.
both NPTL and old linuxthreads behaviour depending on process needs.
Apply to exit_group(), getpid() and getppid() to share them between
compat linux32 (non NPTL) and compat linux (NPTL) on amd64.
ok by manu and christos
Members of the thread group must die without reporting to the parent and
without going to zombie stage. We do that by reparenting to init before
catching a SIGKILL. The parent will not see the child death.
The thread group leader must report the exit status, even if it exits
because of another thread calling exit_group(). We do that by storing the
exit status in struct linux_emuldata_shared, and the exit hook has the
duty of setting struct proc's p_xstat for the thread group leader.
2) For exit/fork/exec hooks, move the NPTL specific code to separate functions
that are shared between COMPAT_LINUX and COMPAT_LINUX32
3) Fix LINUX_CLONE_PARENT_SETTID semantics
threads in a processes and kill them properly. The code is a bit too
complicated, but I could not find a simplier way of dealing with it
- Change getpid() and getppid() semantics to match what Linux does,
and implement gettid(). In the Linux kernel, threads are implemnted
as plain old processes. A thread group is just a set of processes,
with the parent called leader. Thread ID, which are returned by gettid(),
are just the PID of the plain old processes, and getpid() returns the
PID of the thread group leader.
- Remove struct linux32_emuldata. COMPAT_LINUX32 uses a lot of COMPAT_LINUX
code, where a struct linux_emuldata is assumed. By having distinct emuldata
structure with different sizes and layouts, we caused kernel memory
corruptions.
- Fix setprioriry() and getpriority()
Thanks to Nicolas Joly for tracking down the problem and providing me the
hardware to fix them.
riastradh