needs instead of relying on idiosyncratic hacks in the tty subsystem.
Also add module code since this can now be compiled as a module.
Silence by: -hackers, -audit
simpler for npx exceptions that start as traps (no assembly required...)
and works better for npx exceptions that start as interrupts (there is
no longer a problem for nested interrupts).
Submitted by: original (pre-SMPng) version by luoqi
shm_deallocate_segment because shmexit_myhook calls it, and the latter
should always be called with it already held.
Submitted by: dwmalone, dd
Approved by: alfred
- Don't release the vm mutex early in pipespace() but instead hold it
across vm_object_deallocate() if vm_map_find() returns an error and
across pipe_free_kmem() if vm_map_find() succeeds.
- Add a XXX above a zfree() since zalloc already has its own locking,
one would hope that zfree() wouldn't need the vm lock.
vm_mtx does not recurse and is required for most low level
vm operations.
faults can not be taken without holding Giant.
Memory subsystems can now call the base page allocators safely.
Almost all atomic ops were removed as they are covered under the
vm mutex.
Alpha and ia64 now need to catch up to i386's trap handlers.
FFS and NFS have been tested, other filesystems will need minor
changes (grabbing the vm lock when twiddling page properties).
Reviewed (partially) by: jake, jhb
lock. Since we won't actually block on a try lock operation, it's not
a problem. Add a comment explaining why it is safe to skip lock order
checking with try locks.
- Remove the ithread list lock spin lock from the order list.
sleep locks.
- Delay returning from ithread_remove_handler() until we are certain that
the interrupt handler being removed has in fact been removed from the
ithread.
- XXX: There is still a problem in that nothing protects the kernel from
adding a new handler while the ithread is running, though with our
current architectures this is not a problem.
Requested by: gibbs (2)
- Attach a writable sysctl to bootverbose (debug.bootverbose) so it can be
toggled after boot.
- Move the printf of the version string to a SI_SUB_COPYRIGHT SYSINIT just
afer the display of the copyright message instead of doing it by hand in
three MD places.
follows: the effective uid of p1 (subject) must equal the real, saved,
and effective uids of p2 (object), p2 must not have undergone a
credential downgrade. A subject with appropriate privilege may override
these protections.
In the future, we will extend these checks to require that p1 effective
group membership must be a superset of p2 effective group membership.
Obtained from: TrustedBSD Project
Remove comment about setting error for reads on EOF, read returns 0 on
EOF so the code should be ok.
Remove non-effective priority boost, PRIO+1 doesn't do anything
(according to McKusick), if a real priority boost is needed it should
have been +4.
Style fixes:
.) return foo -> return (foo)
.) FLAG1|FlAG2 -> FLAG1 | FlAG2
.) wrap long lines
.) unwrap short lines
.) for(i=0;i=foo;i++) -> for (i = 0; i=foo; i++)
.) remove braces for some conditionals with a single statement
.) fix continuation lines.
md5 couldn't verify the binary because some code had to
be shuffled around to address the style issues.
the number of references on the filesystem root vnode to be both
expected and released. Many filesystems hold an extra reference on
the filesystem root vnode, which must be accounted for when
determining if the filesystem is busy and then released if it isn't
busy. The old `skipvp' approach required individual filesystem
xxx_unmount functions to re-implement much of vflush()'s logic to
deal with the root vnode.
All 9 filesystems that hold an extra reference on the root vnode
got the logic wrong in the case of forced unmounts, so `umount -f'
would always fail if there were any extra root vnode references.
Fix this issue centrally in vflush(), now that we can.
This commit also fixes a vnode reference leak in devfs, which could
result in idle devfs filesystems that refuse to unmount.
Reviewed by: phk, bp
- Require the proc lock be held for killproc() to allow for the vmdaemon to
kill a process when memory is exhausted while holding the lock of the
process to kill.
When people access /dev/tty, locate their controlling tty and return
the dev_t of it to them. This basically makes /dev/tty act like
a variant symlink sort of thing which is much simpler than all the
mucking about with vnodes.
- Since polling should not involve sleeping, keep holding a
process lock upon scanning file descriptors.
- Hold a reference to every file descriptor prior to entering
polling loop in order to avoid lock order reversal between
lockmgr and p_mtx upon calling fdrop() in fo_poll().
(NOTE: this work has not been done for netncp and netsmb
yet because a socket itself has no reference counts.)
Reviewed by: jhb
KASSERT when vp->v_usecount is zero or negative. In this case, the
"v*: negative ref cnt" panic that follows is much more appropriate.
Reviewed by: mckusick
fail due to witness exhausting its internal resources and shutting down.
Reported by: Szilveszter Adam <sziszi@petra.hos.u-szeged.hu>
Tested by: David Wolfskill <david@catwhisker.org>
The pipe code could not handle running out of kva, it would panic
if that happened. Instead return ENFILE to the application which
is an acceptable error return from pipe(2).
There was some slightly tricky things that needed to be worked on,
namely that the pipe code can 'realloc' the size of the buffer if
it detects that the pipe could use a bit more room. However if it
failed the reallocation it could not cope and would panic. Fix
this by attempting to grow the pipe while holding onto our old
resources. If all goes well free the old resources and use the
new ones, otherwise continue to use the smaller buffer already
allocated.
While I'm here add a few blank lines for style(9) and remove
'register'.
process on fork(2).
It is the supposed behavior stated in the manpage of sigaction(2), and
Solaris, NetBSD and FreeBSD 3-STABLE correctly do so.
The previous fix against libc_r/uthread/uthread_fork.c fixed the
problem only for the programs linked with libc_r, so back it out and
fix fork(2) itself to help those not linked with libc_r as well.
PR: kern/26705
Submitted by: KUROSAWA Takahiro <fwkg7679@mb.infoweb.ne.jp>
Tested by: knu, GOTOU Yuuzou <gotoyuzo@notwork.org>,
and some other people
Not objected by: hackers
MFC in: 3 days
implementation. Move from direct uid 0 comparision to using suser_xxx()
call with the same semantics. Simplify CAN_AFFECT() macro as passed
pcred was redundant. The checks here still aren't "right", but they
are probably "better".
Obtained from: TrustedBSD Project
struct lock_instance that is stored in the per-process and per-CPU lock
lists. Previously, the lock lists just kept a pointer to each lock held.
That pointer is now replaced by a lock instance which contains a pointer
to the lock object, the file and line of the last acquisition of a lock,
and various flags about a lock including its recursion count.
- If we sleep while holding a sleepable lock, then mark that lock instance
as having slept and ignore any lock order violations that occur while
acquiring Giant when we wake up with slept locks. This is ok because of
Giant's special nature.
- Allow witness to differentiate between shared and exclusive locks and
unlocks of a lock. Witness will now detect the case when a lock is
acquired first in one mode and then in another. Mutexes are always
locked and unlocked exclusively. Witness will also now detect the case
where a process attempts to unlock a shared lock while holding an
exclusive lock and vice versa.
- Fix a bug in the lock list implementation where we used the wrong
constant to detect the case where a lock list entry was full.
uses lockmgr locks and this leads to a lock order reversal. At this point
in wait1() the process is not on any process lists or in the process tree,
so no other process should be able to find it or have a reference to it
anyways, so the locking is not needed.
other "system" header files.
Also help the deprecation of lockmgr.h by making it a sub-include of
sys/lock.h and removing sys/lockmgr.h form kernel .c files.
Sort sys/*.h includes where possible in affected files.
OK'ed by: bde (with reservations)
- add a missing break which caused RTP_SET to always return EINVAL
- break instead of returning if p_can fails so proc_lock is always
dropped correctly
- only copyin data that is actually needed
- use break instead of goto
- make rtp_to_pri return EINVAL instead of -1 if the values are out
or range so we don't have to translate
