and stop recalculating alignment for PIE base, which was off by one
power of two.
Suggested and reviewed by: markj
Tested by: pho
Sponsored by: The FreeBSD Foundation
MFC after: 1 week
Differential revision: https://reviews.freebsd.org/D33359
Only accept at most superpage alignment, or if the arch does not have
superpages supported, artificially limit it to PAGE_SIZE * 1024.
This is somewhat arbitrary, and e.g. could change what binaries do
we accept between native i386 vs. amd64 ia32 with superpages disabled,
but I do not believe the difference there is affecting anybody with
real (useful) binaries.
Reported and tested by: pho
Reviewed by: markj
Sponsored by: The FreeBSD Foundation
MFC after: 1 week
Differential revision: https://reviews.freebsd.org/D33359
Invalid (artificial) layout of the loadable ELF segments might result in
triggering the assertion. This means that the file should not be
executed, regardless of the kernel debug mode. Change calling
conventions for rnd_elf{32,64} helpers to allow returning an error, and
abort activation with ENOEXEC if its invariants are broken.
Reported and tested by: pho
Reviewed by: markj
Sponsored by: The FreeBSD Foundation
MFC after: 1 week
Differential revision: https://reviews.freebsd.org/D33359
Introduce new MSGBUF_WRAP flag, indicating that buffer has wrapped
at least once and does not keep zeroes from the last msgbuf_clear().
It allows msgbuf_peekbytes() to return only real data, not requiring
every consumer to trim the leading zeroes after doing pointless copy.
The most visible effect is that kern.msgbuf sysctl now always returns
proper zero-terminated string, not only after the first buffer wrap.
MFC after: 1 week
Sponsored by: iXsystems, Inc.
MNTK_NOKNOTE was introduced in 679985d03a64f5dfb4355538ae6e3b70f8347f38
(dated 2005), VV_NOKNOTE in 34cc826ae8999f454dd6cb9c77d17ce83b169f92 few
months later.
Neither was ever used by anything in the tree.
Add an idletime user group that allows non-root users to run processes
with idle scheduling priority. Privileges are granted by a MAC policy in
the mac_priority module. For this purpose, the kernel privilege
PRIV_SCHED_IDPRIO was added to sys/priv.h (kernel module ABI change).
Deprecate the system wide sysctl(8) knob
security.bsd.unprivileged_idprio which lets any user run idle priority
processes, regardless of context. While the knob is still working, it is
marked as deprecated in the description and in the man pages.
MFC after: 2 weeks
Differential revision: https://reviews.freebsd.org/D33338
The privilege allows the holder to assign idle priority type to thread
or process.
MFC after: 2 weeks
Differential revision: https://reviews.freebsd.org/D33338
Add bus_topo_assert() and implmement it as GIANT_REQUIRED for the
moment. This will allow us to change more easily to a newbus-specific
lock int he future.
Sponsored by: Netflix
Reviewed by: wulf, mav, jhb
Differential Revision: https://reviews.freebsd.org/D31833
Mark the sysctls MPSAFE and pickup the bus topo lock while processing
them.
Sponsored by: Netflix
Reviewed by: mav, jhb
Differential Revision: https://reviews.freebsd.org/D31832
Create a wrapper for newbus to take giant and for busses to take it too.
bus_topo_lock() should be called before interacting with newbus routines
and unlocked with bus_topo_unlock(). If you need the topology lock for
some reason, bus_topo_mtx() will provide that.
Sponsored by: Netflix
Reviewed by: mav
Differential Revision: https://reviews.freebsd.org/D31831
With various firmware files used by graphics and wireless drivers
we are exceeding the current 32 character module name (file path
in kldxref) length.
In order to overcome this issue bump it to the maximum path length
for the next version.
To be able to MFC provide backward compat support for another version
of the struct as the offsets for the second half change due to the
array size increase.
MAXMODNAME being defined to MAXPATHLEN needs param.h to be
included first. With only 7 modules (or LinuxKPI module.h) not
doing that adjust them rather than including param.h in module.h [1].
Reported by: Greg V (greg unrelenting.technology)
Sponsored by: The FreeBSD Foundation
Suggested by: imp [1]
MFC after: 10 days
Reviewed by: imp (and others to different level)
Differential Revision: https://reviews.freebsd.org/D32383
The only requirement for SV_DSO_SIG here is that the flags match between
the source and target sysentvec.
The current assertion is too strict and fails on powerpc64, the only
other architecture than amd64 that uses this function, which doesn't
implement sigtramp in a VDSO.
Reviewed by: kib
Differential Revision: https://reviews.freebsd.org/D33355
allowing linking to static symbols from other files. Default the new
settings to true, delaying the change of the kernel linker behavior
for other day.
Suggested by: emaste
PR: 207898
Reviewed by: emaste, markj
Sponsored by: The FreeBSD Foundation
MFC after: 1 week
Differential revision: https://reviews.freebsd.org/D32878
In particular, this prevents resolving locals from other files.
To access debug symbol tables, add LINKER_LOOKUP_DEBUG_SYMBOL and
LINKER_DEBUG_SYMBOL_VALUES kobj methods, which are allowed to use
any types of present symbols in all tables.
PR: 207898
Reviewed by: emaste, markj
Sponsored by: The FreeBSD Foundation
MFC after: 1 week
Differential revision: https://reviews.freebsd.org/D32878
that returns struct kinfo_file for the given file descriptor. Among
other data, it also returns kf_path, if file op was able to restore file
path.
Reviewed by: jhb, markj
Sponsored by: The FreeBSD Foundation
MFC after: 1 week
Differential revision: https://reviews.freebsd.org/D33277
Specify that the only supported architecture for a.out is ia32 (either
i386 or amd64 host kernel).
Requested by: emaste
Sponsored by: The FreeBSD Foundation
MFC after: 1 week
Differential revision: https://reviews.freebsd.org/D32960
This reverts commit 266f97b5e9a7958e365e78288616a459b40d924a, reversing
changes made to a10253cffea84c0c980a36ba6776b00ed96c3e3b.
A mismerge of a merge to catch up to main resulted in files being
committed which should not have been.
which will report where the epoch was entered and also
mark the tracker, so that exit will also be reported.
Helps to understand epoch entrance/exit scenarios in
complex cases, like network stack. As everything else
under EPOCH_TRACE it is a developer only tool.
With introduction of epoch(9) synchronization to network stack the
inpcb database became protected by the network epoch together with
static network data (interfaces, addresses, etc). However, inpcb
aren't static in nature, they are created and destroyed all the
time, which creates some traffic on the epoch(9) garbage collector.
Fairly new feature of uma(9) - Safe Memory Reclamation allows to
safely free memory in page-sized batches, with virtually zero
overhead compared to uma_zfree(). However, unlike epoch(9), it
puts stricter requirement on the access to the protected memory,
needing the critical(9) section to access it. Details:
- The database is already build on CK lists, thanks to epoch(9).
- For write access nothing is changed.
- For a lookup in the database SMR section is now required.
Once the desired inpcb is found we need to transition from SMR
section to r/w lock on the inpcb itself, with a check that inpcb
isn't yet freed. This requires some compexity, since SMR section
itself is a critical(9) section. The complexity is hidden from
KPI users in inp_smr_lock().
- For a inpcb list traversal (a pcblist sysctl, or broadcast
notification) also a new KPI is provided, that hides internals of
the database - inp_next(struct inp_iterator *).
Reviewed by: rrs
Differential revision: https://reviews.freebsd.org/D33022
The vast majority of the busy/unbusy users in the tree don't acquire
Giant before calling device_busy/unbusy. However, if multiple threads
are opening a file, say, that causes the device to busy/unbusy, then we
can race to the root marking things busy. Move to using a reference
count to keep track of how many times a device_t has been made busy. Use
that count to make the same decisions that we'd make with the old device
state.
Note: gpiopps.c uses D_TRACKCLOSE. Others do as well. However, there's a
known race with closes that will be corrected for all the drivers that
do this in a future commit.
Sponsored by: Netflix
Reviewed by: hselasky, jhb
Differential Revision: https://reviews.freebsd.org/D26284
This reverts commit 08e781915363f98f4318a864b3b5a52bd99424c6.
Commit message was for a very old version of the patch. Will re-commit
with the right one since it's so bad. There's no locked versions of
it...that code was reworked to use refcnt APIs.
Noticed by: jhb, jtrc27
Sponsored by: Netflix
The vast majority of the busy/unbusy users in the tree don't acquire Giant
before calling device_busy/unbusy. However, if multiple threads are opening a
file, say, that causes the device to busy/unbusy, then we can race to the root
marking things busy. Create a new device_busy_locked and device_unbusy_locked
that are the current implemntations of device_busy and device_unbusy. Make
device_busy and unbusy acquire Giant before calling the _locked versrions. Since
we never sleep in the busy/unbusy path, Giant's single threaded semantics
suffice to keep this safe.
Sponsored by: Netflix
Reviewed by: hselasky, jhb
Differential Revision: https://reviews.freebsd.org/D26284
There are two places where we convert from a timecounter delta to
a bintime delta: tc_windup and bintime_off.
Both functions use the same calculations when the timecounter delta is
small. But for a large delta (greater than approximately an equivalent
of 1 second) the calculations were different. Both functions use
approximate calculations based on th_scale that avoid division. Both
produce values slightly greater than a true value, calculated with
division by tc_frequency, would be. tc_windup is slightly more
accurate, so its result is closer to the true value and, thus, smaller
than bintime_off result.
As a consequence there can be a jump back in time when time hands are
switched after a long period of time (a large delta). Just before the
switch the time would be calculated with a large delta from
th_offset_count in bintime_off. tc_windup does the switch using its own
calculations of a new th_offset using the large delta. As explained
earlier, the new th_offset may end up being less than the previously
produced binuptime. So, for a period of time new binuptime values may
be "back in time" comparing to values just before the switch.
Such a jump must never happen. All the code assumes that the uptime is
monotonically nondecreasing and some code works incorrectly when that
assumption is broken. For example, we have observed sleepq_timeout()
ignoring a timeout when the sbinuptime value obtained by the callout
code was greater than the expiration value, but the sbinuptime obtained
in sleepq_timeout() was less than it. In that case the target thread
would never get woken up.
The unified calculations should ensure the monotonic property of the
uptime.
The problem is quite rare as normally tc_windup should be called HZ
times per second (typically 1000 or 100). But it may happen in VMs on
very busy hypervisors where a VM's virtual CPU may not get an execution
time slot for a second or more.
Reviewed by: kib
MFC after: 2 weeks
Sponsored by: Panzura LLC
