sxlock, via the sx_{s, x}lock_sig() interface, or plain lockmgr), will
leave the waiters flag on forcing the owner to do a wakeup even when if
the waiter queue is empty.
That operation may lead to a deadlock in the case of doing a fake wakeup
on the "preferred" (based on the wakeup algorithm) queue while the other
queue has real waiters on it, because nobody is going to wakeup the 2nd
queue waiters and they will sleep indefinitively.
A similar bug, is present, for lockmgr in the case the waiters are
sleeping with LK_SLEEPFAIL on. In this case, even if the waiters queue
is not empty, the waiters won't progress after being awake but they will
just fail, still not taking care of the 2nd queue waiters (as instead the
lock owned doing the wakeup would expect).
In order to fix this bug in a cheap way (without adding too much locking
and complicating too much the semantic) add a sleepqueue interface which
does report the actual number of waiters on a specified queue of a
waitchannel (sleepq_sleepcnt()) and use it in order to determine if the
exclusive waiters (or shared waiters) are actually present on the lockmgr
(or sx) before to give them precedence in the wakeup algorithm.
This fix alone, however doesn't solve the LK_SLEEPFAIL bug. In order to
cope with it, add the tracking of how many exclusive LK_SLEEPFAIL waiters
a lockmgr has and if all the waiters on the exclusive waiters queue are
LK_SLEEPFAIL just wake both queues.
The sleepq_sleepcnt() introduction and ABI breakage require
__FreeBSD_version bumping.
Reported by: avg, kib, pho
Reviewed by: kib
Tested by: pho
to wcscoll(3). Newline characters could cause incorrect results when
comparing lines.
Also, if an input line didn't contain a newline character, it was
omitted from the output. According to my interpretation, SUSv3 requires
that the newline is always printed.
Add regression tests for the cases. [1]
PR: bin/140976
Submitted by: D'Arcy Cain (original version) [1]
Approved by: trasz (mentor)
this requires a small reordering of headers and a few #defines to
map functions not available in userland.
Remove a useless #ifndef block at the beginning of the file.
Introduce (temporarily) rn_init2(), see the comment in the code
for the proper long term change.
No ABI or functional change.
MFC after: 7 days
to something else. So add code to detect when things don't match and
give the user choices about how to fix it.
If we're using -P and something in the above check needs to be moved
we need to have the directory there for it, so create it at the
beginning and delete empty versions of it at the end.
The case where something used to be a file or link and now is supposed
to be a directory (e.g., /etc/security) is especially dangerous, so
make failure to install a necessary directory in $DESTDIR a fatal error.
was made in r199543 to remove MTX_RECURSE. These routines can be
called in device attach phase(e.g. mii_phy_probe()) so checking
assertion here is not right as caller does not hold a driver lock.
The information used by the "Last login:"-line is obtained by using
ulog_setutxfile(3) to switch to the lastlog database. Login and logout
are performed using the utility functions ulog_login(3) and
ulog_logout(3).
This also means we must build libulog during bootstrap.
Approved by: des
used by ggatectl, flags are potentially useful).
Other parts are internal kernel data structures and should
not be visible to userland.
No API change involved.
MFC after: 3 days
The rewrite of the interrupt handler includes:
o loop until all pending interrupts are handled. This closes a
race condition.
o count the number of interrupt sources we handled so that we can
properly return FILTER_HANDLED or FILTER_STRAY when we break out
of the loop.
o When matching the interrupt source to the devices that have that
source pending, check only from the set of devices we found to
have a pending interrupt.
PR: kern/140947
MFC after: 3 days
management over the data endpoint causes communication to die.
Take this one step further and model it on the existing NetBSD quirk and import
other device IDs from them.
Obtained from: NetBSD
It turns out these entries do make Terminal.app behave a little better.
According to Thomas Dickey, Terminal.app should use TERM=nsterm anyway,
but we don't support this yet. Already having an improved termcap entry
helps, so I am going to MFC this change after all.
Suggested by: Leonidas Tsampros <ltsampros upnet gr>
MFC after: 1 month
- cast the result of LEN() to int as this is the main usage.
- use LEN() in one place where it was forgotten.
- Document the use of a static variable in rw mode.
More small changes to follow.
MFC after: 7 days
1) Avoid an infinite loop in the header resync for certain malformed
archives.
2) Don't try to match hardlinks if the nlinks count is < 2. This
reduces the likelihood of a false hardlink match due to ino truncation.
MFC after: 7 days
