man-pages-4.11 is released

[Michael Kerrisk (man-pages)]

The Linux man-pages maintainer proudly announces:

    man-pages-4.11 - man pages for Linux

This release resulted from patches, bug reports, reviews, and comments
from over 30 contributors. The release sees a large number of changes:
over 300 commits changing more than 100 pages. The changes include the
addition of 5 pages, significant rewriting of 1 page, and enhancements
to many other 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_4.11

A short summary of the release is blogged at:
http://linux-man-pages.blogspot.com/2017/05/man-pages-411-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 on LKML is shown below.

Cheers,

Michael

==================== Changes in man-pages-4.11 ====================

Released: 2017-05-03, Baden, Switzerland


New and rewritten pages
-----------------------

ioctl_userfaultfd.2
    Michael Kerrisk, Mike Rapoport
        New page describing ioctl(2) operations for userfaultfd

statx.2
    David Howells, Michael Kerrisk  [Andreas Dilger]
        New page describing statx(2) system call added in Linux 4.11

userfaultfd.2
    Mike Rapoport, Michael Kerrisk  [Andrea Arcangeli]
        New page describing userfaultfd(2) system call.

pthread_atfork.3
    Michael Kerrisk
        New page describing pthread_atfork(3)

slabinfo.5
    Michael Kerrisk
        Rewrite to try to bring the content close to current reality
            There's still gaps to fill in, but the existing page
            was in any case hugely out of date.

inode.7
    Michael Kerrisk
        New page with information about inodes
            David Howells provided a statx(2) page that duplicated much of
            the information from stat(2). Avoid such duplication
            by moving the common information in stat(2) and statx(2)
            to a new page.


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

ioctl_ns.2
    Michael Kerrisk
        Document the NS_GET_NSTYPE operation added in Linux 4.11
    Michael Kerrisk
        Document the NS_GET_OWNER_UID operation added in Linux 4.11

proc.5
    Michael Kerrisk
        Document /proc/sys/kernel/sched_child_runs_first

namespaces.7
    Michael Kerrisk
        Document the /proc/sys/user/* files added in Linux 4.9

socket.7
    Francois Saint-Jacques, Michael Kerrisk
        Document SO_INCOMING_CPU


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

clone.2
unshare.2
    Michael Kerrisk
        Exceeding one of the limits in /proc/sys/user/* can cause ENOSPC
    Michael Kerrisk
        CLONE_NEWPID yields ENOSPC if nesting limit of PID namespaces is reached
    Michael Kerrisk
        Exceeding the maximum nested user namespace limit now gives ENOSPC
            Formerly, if the limit of 32 nested user namespaces was exceeded,
            the error EUSERS resulted. Starting with Linux 4.9, the error
            is ENOSPC.

epoll_ctl.2
    Michael Kerrisk
        Defer to poll(2) for an explanation of EPOLLIN
    Michael Kerrisk  [Nicolas Biscos]
        EPOLLERR is also set on write end of a pipe when the read end is closed
    Michael Kerrisk  [Nicolas Biscos]
        Give the reader a clue that the 'events' field can be zero
            'events' specified as zero still allows EPOLLHUP and
            EPOLLERR to be reported.

_exit.2
    Michael Kerrisk
        On exit, child processes may be inherited by a "subreaper"
            It is no longer necessarily true that orphaned processes
            are inherited by PID 1.
    Michael Kerrisk
        Only the least significant byte of exit status is passed to the parent

fcntl.2
    Michael Kerrisk
        Mention memfd_create() in the discussion of file seals
            Give the reader a clue about what kinds of objects can
            be employed with file seals.
    Michael Kerrisk
        File seals are not generally applicable to tmpfs(5) files
            As far as I can see, file seals can be applied only to
            memfd_create(2) file descriptors. This was checked by experiment
            and by reading mm/shmem.c::shmem_get_inode((), where one finds
            the following line that applies to all new shmem files:

                            info->seals = F_SEAL_SEAL;

            Only in the code of the memfd_create() system call is this
            setting reversed (in mm/shmem.c::memfd_create):

                    if (flags & MFD_ALLOW_SEALING)
                            info->seals &= ~F_SEAL_SEAL;
poll.2
    Michael Kerrisk
        Expand discussion of POLLPRI
    Michael Kerrisk  [Nicolas Biscos]
        POLLERR is also set on write end of a pipe when the read end is closed

prctl.2
    Mike Frysinger
        PR_SET_MM: Document new PR_SET_MM_MAP{,_SIZE} helpers
    Michael Kerrisk
        Explain rationale for use of subreaper processes
    Michael Kerrisk
        Note semantics of child_subreaper setting on fork() and exec()
    Michael Kerrisk
        Improve description of PR_SET_CHILD_SUBREAPER

select.2
    Michael Kerrisk  [Matthew Wilcox, Carlos O'Donell]
        Linux select() is buggy wrt POSIX in its check for EBADF errors
    Michael Kerrisk
        Show correspondence between select() and poll() readiness notifications
    Michael Kerrisk
        Give a hint that sets must be reinitialized if using select() in a loop

signalfd.2
    Michael Kerrisk
        SIGKILL and SIGSTOP are silently ignored in 'mask'

sigwaitinfo.2
    Michael Kerrisk
        sigwaitinfo() can't be used to accept synchronous signals

wait.2
    Michael Kerrisk
        Orphaned children may be adopted by a "subreaper", rather by than PD 1

grantpt.3
    Michael Kerrisk
        Tell a more nuanced story about what grantpt() does or does not do

shm_open.3
    Michael Kerrisk
        Clarify that POSIX shared memory uses tmpfs(5)

pid_namespaces.7
    Michael Kerrisk
        The maximum nesting depth for PID namespaces is 32

ld.so.8
    Michael Kerrisk
        Expand description of /etc/ld.so.preload

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