Bhyve's vmm is a self-contained modern component and thus a good
candidate for use of C99 types.
Reviewed by: jhb, kib, markj, Patrick Mooney
MFC after: 1 week
Sponsored by: The FreeBSD Foundation
Differential Revision: https://reviews.freebsd.org/D21036
disk blocks, set the FORCE flag in the call to chkiq() or chkdq() since
the user is always allowed to return resources and hence there is no need
to check the user's credential .
Reported by: Christopher Krah, Thomas Barabosch, and Jan-Niclas Hilgert of Fraunhofer FKIE
Reported as: FS-1-UFS-1: Denial Of Service in mount (prison_priv_check)
Discussed with: kib
MFC: 1 week
Sponsored by: Netflix
Guest PPC OSs running under a hypervisor may communicate the features they
support, in order for the hypervisor to expose a virtualized machine in the way
the client (guest OS) expects (see LoPAPR 1.1 - B.6.2.3).
This is done by calling the "/ibm,client-architecture-support" (CAS) method,
informing supported features in option vectors. Until now, FreeBSD wasn't
using CAS, but instead relied on hypervisor/QEMU's defaults.
The problem is that, without CAS, it is very inconvenient to run POWER9 VMs on
a POWER9 host running with radix enabled. This happens because, in this case,
the QEMU default is to present the guest OS a dual MMU (HPT/RPT), instead of
presenting a regular HPT MMU, as FreeBSD expects, resulting in an early panic.
The known workarounds required either changing the host to disable radix or
passing a flag to QEMU to run in a POWER8 compatible mode.
With CAS, FreeBSD is now able to communicate that it wants an HPT MMU,
independent of the host setup, which now makes FreeBSD work on POWER9/pseries,
with KVM enabled and without hugepages (support added in a previous commit).
As CAS is invoked through OpenFirmware's call-method interface, it needs to be
performed early, when OpenFirmware is still operational. Besides, now that FDT
is the default way to inspect the device tree on PPC, OFW call-method feature
will be unavailable by default, when control is passed to the kernel. Because
of this, the call to CAS is being performed at the loader, instead of at the
kernel.
To avoid regressions with old platforms, this change uses CAS only on
POWER8/POWER9.
Reviewed by: jhibbits
Differential Revision: https://reviews.freebsd.org/D20827
This effectively makes the stack base on the csu _start entry
randomized.
The gap is enabled if ASLR is for the ABI is enabled, and then
kern.elf{64,32}.aslr.stack_gap specify the max percentage of the
initial stack size that can be wasted for gap. Setting it to zero
disables the gap, and max is capped at 50%.
Only amd64 for now.
Reviewed by: cem, markj
Discussed with: emaste
MFC after: 2 weeks
Sponsored by: The FreeBSD Foundation
Differential revision: https://reviews.freebsd.org/D21081
In some corner cases of static linking and unexpected libraries order
on the linker command line, libc symbol might preempt the same libthr
symbol, in which case libthr jump table points back to libc causing
either infinite recursion or loop. Handle all of such symbols by
using private libthr names for them, ensuring that the right pointers
are installed into the table.
In collaboration with: arichardson
PR: 239475
Tested by: pho
MFC after: 2 weeks
Sponsored by: The FreeBSD Foundation
Differential revision: https://reviews.freebsd.org/D21088
In some corner cases of static linking and unexpected libraries order
on the linker command line, libc symbol might preempt the same libthr
symbol, in which case libthr jump table points back to libc causing
either infinite recursion or loop. Handle all of such symbols by
using private libthr names for them, ensuring that the right pointers
are installed into the table.
In collaboration with: arichardson
PR: 239475
Tested by: pho
MFC after: 2 weeks
Sponsored by: The FreeBSD Foundation
Differential revision: https://reviews.freebsd.org/D21088
In particular, restart should be only done when the failure is
transient. For this, recheck the count1 value after the operation.
Note that do_sem_wait() is older usem interface.
Reported and tested by: bdrewery
Sponsored by: The FreeBSD Foundation
MFC after: 1 week
This adds several previously missed but important subcommands to list
namespaces and controllers. It also fixes few previously added but
just found with real testing to be broken subcommands.
Also while there, add possibility to explicitly specify nsid for
`nvmecontrol identify` subcommand. It may be useful to specify nsids
not having own devices, for example 0xffffffff, or just newly created
ones.
MFC after: 2 weeks
Relnotes: yes
Sponsored by: iXsystems, Inc.
This allows to simulated disk that is responding slowly to the IO requests.
Reviewed by: markj, bcr, pjd (previous version)
Differential Revision: https://reviews.freebsd.org/D21052
Avoid potential structure padding leak. r350294 identified a leak via
static analysis; although there's no report of a leak with the
DIOCGETSRCNODES ioctl it's a good practice to zero the memory.
Suggested by: kp
MFC after: 3 days
Sponsored by: The FreeBSD Foundation
This is a backport of LLVM commit 8331f61a51a7a0a1efbf5ed398e181593023d151,
llvm-svn: 353981:
ELF: Allow GOT relocs pointing to non-preemptable ifunc to resolve to an
IRELATIVE where possible.
This is needed in order to make ifuncs work correctly on PPC64.
It fixes an issue with lld, in which it would skip emitting necessary IRELATIVE
relocations. Without this change, indirect calls to ifuncs would result in a
segmentation fault, in static binaries or when defined in the main binary
(outside shared libraries).
This change also reverts the local
"Preserve relocations against ifuncs when -zifunc-noplt" commit and
replaces it by its upstream version, as part of the merge.
Reviewed by: markj
Differential Revision: https://reviews.freebsd.org/D21102
The motivation for this change is to allow wrappers around shm to be written
that don't set CLOEXEC. kern_shm_open currently accepts O_CLOEXEC but sets
it unconditionally. kern_shm_open is used by the shm_open(2) syscall, which
is mandated by POSIX to set CLOEXEC, and CloudABI's sys_fd_create1().
Presumably O_CLOEXEC is intended in the latter caller, but it's unclear from
the context.
sys_shm_open() now unconditionally sets O_CLOEXEC to meet POSIX
requirements, and a comment has been dropped in to kern_fd_open() to explain
the situation and add a pointer to where O_CLOEXEC setting is maintained for
shm_open(2) correctness. CloudABI's sys_fd_create1() also unconditionally
sets O_CLOEXEC to match previous behavior.
This also has the side-effect of making flags correctly reflect the
O_CLOEXEC status on this fd for the rest of kern_shm_open(), but a
glance-over leads me to believe that it didn't really matter.
Reviewed by: kib, markj
MFC after: 1 week
Differential Revision: https://reviews.freebsd.org/D21119
mapping and then destroy one of the 4 KB page mappings so that there is a
potential trigger for repromotion. Currently, we destroy the first 4 KB
page mapping that falls within the (current) superpage mapping or the
virtual address range [sva, eva). However, I have found empirically that
destroying the last 4 KB mapping produces slightly better results,
specifically, more promotions and fewer failed promotion attempts.
Accordingly, this revision changes pmap_advise() to destroy the last 4 KB
page mapping. It also replaces some nearby uses of boolean_t with bool.
Reviewed by: kib, markj
Differential Revision: https://reviews.freebsd.org/D21115
While old devices may not support 10 byte MODE SENSE/MODE SELECT commands,
new ones may not be able to report all mode pages with 6 byte commands.
This patch makes camcontrol by default start with 10 byte commands and
fall back to 6 byte on ILLEGAL REQUEST error, or 6 byte can be forced.
MFC after: 2 weeks
Sponsored by: iXsystems, Inc.
r350437 presents a merge conflict with r350115, which raised
__FreeBSD_version due to the addition of fusefs's intr/nointr mount options.
Sponsored by: The FreeBSD Foundation
Some warning flags are valid for C++ but not C. GCC 8 complains if you pass
such flags when building a C file. Using a separate variable for these
flags allows building both C and C++ files in the same directory (such as
the fusefs tests) under GCC.
Reviewed by: cem, emaste
MFC after: 2 weeks
Sponsored by: The FreeBSD Foundation
Differential Revision: https://reviews.freebsd.org/D21116
It is assembled using "${CC} -x assembler-with-cpp", which by convention
(bsd.suffixes.mk) uses the .asm extension.
This is a portion of the review referenced below (D18344). That review
also renamed linux_support.s to .S, but that is a functional change
(using the compiler's integrated assembler instead of as) and will be
revisited separately.
MFC after: 1 week
Sponsored by: The FreeBSD Foundation
Differential Revision: https://reviews.freebsd.org/D18344
witness has long had a facility to "bless" designated lock pairs. Lock
order reversals between a pair of blessed locks are not reported upon.
We have a number of long-standing false positive LOR reports; start
marking well-understood LORs as blessed.
This change hides reports about UFS vnode locks and the UFS dirhash
lock, and UFS vnode locks and buffer locks, since those are the two that
I observe most often. In the long term it would be preferable to be
able to limit blessings to a specific site where a lock is acquired,
and/or extend witness to understand why some lock order reversals are
valid (for example, if code paths with conflicting lock orders are
serialized by a third lock), but in the meantime the false positives
frequently confuse users and generate bug reports.
Reviewed by: cem, kib, mckusick
MFC after: 2 weeks
Sponsored by: The FreeBSD Foundation
Differential Revision: https://reviews.freebsd.org/D21039
copy_file_range() operates on a pair of file descriptors; it requires
CAP_READ for the source descriptor and CAP_WRITE for the destination
descriptor.
Reviewed by: kevans, oshogbo
Sponsored by: The FreeBSD Foundation
Differential Revision: https://reviews.freebsd.org/D21113
Attempt to mitigate the security risks around refcount overflows by
introducing a "saturated" state for the counter. Once a counter reaches
INT_MAX+1, subsequent acquire and release operations will blindly set
the counter value to INT_MAX + INT_MAX/2, ensuring that the protected
resource will not be freed; instead, it will merely be leaked.
The approach introduces a small race: if a refcount value reaches
INT_MAX+1, a subsequent release will cause the releasing thread to set
the counter to the saturation value after performing the decrement. If
in the intervening window INT_MAX refcount releases are performed by a
different thread, a use-after-free is possible. This is very difficult
to trigger in practice, and any situation where it could be triggered
would likely be vulnerable to reference count wraparound problems
to begin with. An alternative would be to use atomic_cmpset to acquire
and release references, but this would introduce a larger performance
penalty, particularly when the counter is contended.
Note that refcount_acquire_checked(9) maintains its previous behaviour;
code which must accurately track references should use it instead of
refcount_acquire(9).
Reviewed by: kib, mjg
MFC after: 3 weeks
Sponsored by: The FreeBSD Foundation
Differential Revision: https://reviews.freebsd.org/D21089
The rc.d/account script contains code to create the /var/account dir, so
it hadn't occurred to me that it is normally created via mtree; thanks to
jilles@ for pointing it out.
The current implementation of gzipped a.out support was based
on a very old version of InfoZIP which ships with an ancient
modified version of zlib, and was removed from the GENERIC
kernel in 1999 when we moved to an ELF world.
PR: 205822
Reviewed by: imp, kib, emaste, Yoshihiro Ota <ota at j.email.ne.jp>
Relnotes: yes
Differential Revision: https://reviews.freebsd.org/D21099
Modify strip(1) to not accept multiple input files when an output
file is specified. There is no good way to handle this combination,
and the change is compatible with binutils.
MFC after: 1 week
Sponsored by: The FreeBSD Foundation
Both of these functions atomically unwire a page, optionally attempt
to free the page, and enqueue or requeue the page. Add functions
vm_page_release() and vm_page_release_locked() to perform the same task.
The latter must be called with the page's object lock held.
As a side effect of this refactoring, the buffer cache will no longer
attempt to free mapped pages when completing direct I/O. This is
consistent with the handling of pages by sendfile(SF_NOCACHE).
Reviewed by: alc, kib
MFC after: 2 weeks
Sponsored by: Netflix
Differential Revision: https://reviews.freebsd.org/D20986
