man-pages-4.16 is released

From: Michael Kerrisk (man-pages)
Date: Fri May 04 2018 - 03:43:42 EST


Gidday,

The Linux man-pages maintainer proudly announces:

man-pages-4.16 - man pages for Linux

This release resulted from patches, bug reports, reviews, and comments
from 29 contributors. Around 160 commits changed 62 pages.

Tarball download:
http://www.kernel.org/doc/man-pages/download.html
Git repository:
https://git.kernel.org/cgit/docs/man-pages/man-pages.git/
Online changelog:
http://man7.org/linux/man-pages/changelog.html#release_4.16

A short summary of the release is blogged at:
http://linux-man-pages.blogspot.com/2018/04/man-pages-416-is-released.html

The current version of the pages is browsable at:
http://man7.org/linux/man-pages/

A selection of changes in this release that may be of interest
to readers of LKML is shown below.

Cheers,

Michael

==================== Changes in man-pages-4.16 ====================


Newly documented interfaces in existing pages
---------------------------------------------

membarrier.2
Mathieu Desnoyers [Michael Kerrisk]
Document new membarrier commands introduced in Linux 4.16
Document the following membarrier commands introduced in
Linux 4.16:

MEMBARRIER_CMD_GLOBAL_EXPEDITED
(the old enum label MEMBARRIER_CMD_SHARED is now an
alias to preserve header backward compatibility)
MEMBARRIER_CMD_REGISTER_GLOBAL_EXPEDITED
MEMBARRIER_CMD_PRIVATE_EXPEDITED_SYNC_CORE
MEMBARRIER_CMD_REGISTER_PRIVATE_EXPEDITED_SYNC_CORE

mmap.2
Jan Kara [Ross Zwisler, Michael Kerrisk]
Add description of MAP_SHARED_VALIDATE and MAP_SYNC
Michal Hocko [John Hubbard, Michael Kerrisk, Jann Horn]
Document new MAP_FIXED_NOREPLACE flag
4.17+ kernels offer a new MAP_FIXED_NOREPLACE flag which allows
the caller to atomically probe for a given address range.

readv.2
io_submit.2
JÃrg Billeter
Document RWF_APPEND added in Linux 4.16

capabilities.7
Michael Kerrisk
Describe file capability versioning
Michael Kerrisk [Serge E. Hallyn]
Document namespaced-file capabilities
[There's still more work to be done on this new text]


Changes to individual pages
---------------------------

bpf.2
Michael Kerrisk
Update list of architectures that support JITed eBPF
And note kernel version numbers where support is added.
Michael Kerrisk
Kernel 4.15 added CONFIG_BPF_JIT_ALWAYS_ON
This causes the JIT compiler to be always on and
forces bpf_jit_enable to 1.

fallocate.2
Michael Kerrisk
Since Linux 4.16, Btrfs supports FALLOC_FL_ZERO_RANGE

getrlimit.2
Michael Kerrisk
CAP_SYS_RESOURCE capability is required in *initial user namespace*

mmap.2
Jann Horn
MAP_FIXED is okay if the address range has been reserved
Clarify that MAP_FIXED is appropriate if the specified address
range has been reserved using an existing mapping, but shouldn't
be used otherwise.
mount.2
Michael Kerrisk
ERRORS: add EBUSY for the case of trying to stack same mount twice
Michael Kerrisk
Remove a couple of obsolete EBUSY errors
As far as I can tell, these EBUSY errors disappeared
with the addition of stackable mounts in Linux 2.4.

perf_event_open.2
Song Liu
Add type kprobe and uprobe
Two new types kprobe and uprobe are being added to
perf_event_open(), which allow creating kprobe or
uprobe with perf_event_open. This patch adds
information about these types.

seccomp.2
Michael Kerrisk
Note that execve() may change syscall numbers during life of process
On a multiarch/multi-ABI platform such as modern x86, each
architecture/ABI (x86-64, x32, i386)has its own syscall numbers,
which means a seccomp() filter may see different syscall numbers
over the life of the process if that process uses execve() to
execute programs that has a different architectures/ABIs.
Michael Kerrisk
Note which architectures support seccomp BPF
Michael Kerrisk
In EXAMPLE, clearly note that x32 syscalls are >= X32_SYSCALL_BIT

tmpfs.5
Mike Frysinger
Document current mount options
Some of this content is moved from the mount(8) man page.
Style was based on proc(5) sections.
cgroups.7
Michael Kerrisk
cgroup.events transitions generate POLLERR as well as POLLPRI

namespaces.7
Michael Kerrisk [Konstantin Khlebnikov]
Mention that device ID should also be checked when comparing NS symlinks
When comparing two namespaces symlinks to see if they refer to
the same namespace, both the inode number and the device ID
should be compared. This point was already made clear in
ioctl_ns(2), but was missing from this page.
Michael Kerrisk
Note an idiosyncrasy of /proc/[pid]/ns/pid_for_children
/proc/[pid]/ns/pid_for_children has a value only after first
child is created in PID namespace. Verified by experiment.

network_namespaces.7
Michael Kerrisk
Network namespaces isolate the UNIX domain abstract socket namespace
vdso.7
Michael Kerrisk
VDSO symbols (system calls) are not visible to seccomp(2) filters

--
Michael Kerrisk
Linux man-pages maintainer; http://www.kernel.org/doc/man-pages/
Linux/UNIX System Programming Training: http://man7.org/training/