<feed xmlns='http://www.w3.org/2005/Atom'>
<title>user/sven/linux.git/init, branch v5.8.8</title>
<subtitle>Linux Kernel
</subtitle>
<id>https://git.stealer.net/cgit.cgi/user/sven/linux.git/atom?h=v5.8.8</id>
<link rel='self' href='https://git.stealer.net/cgit.cgi/user/sven/linux.git/atom?h=v5.8.8'/>
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<updated>2020-08-21T11:15:01Z</updated>
<entry>
<title>bootconfig: Fix to find the initargs correctly</title>
<updated>2020-08-21T11:15:01Z</updated>
<author>
<name>Masami Hiramatsu</name>
<email>mhiramat@kernel.org</email>
</author>
<published>2020-08-04T02:52:13Z</published>
<link rel='alternate' type='text/html' href='https://git.stealer.net/cgit.cgi/user/sven/linux.git/commit/?id=9213dd60f18187d1dbacc63693014b0c9abefa2c'/>
<id>urn:sha1:9213dd60f18187d1dbacc63693014b0c9abefa2c</id>
<content type='text'>
commit 477d08478170469d10b533624342d13701e24b34 upstream.

Since the parse_args() stops parsing at '--', bootconfig_params()
will never get the '--' as param and initargs_found never be true.
In the result, if we pass some init arguments via the bootconfig,
those are always appended to the kernel command line with '--'
even if the kernel command line already has '--'.

To fix this correctly, check the return value of parse_args()
and set initargs_found true if the return value is not an error
but a valid address.

Link: https://lkml.kernel.org/r/159650953285.270383.14822353843556363851.stgit@devnote2

Fixes: f61872bb58a1 ("bootconfig: Use parse_args() to find bootconfig and '--'")
Cc: stable@vger.kernel.org
Reported-by: Arvind Sankar &lt;nivedita@alum.mit.edu&gt;
Suggested-by: Arvind Sankar &lt;nivedita@alum.mit.edu&gt;
Signed-off-by: Masami Hiramatsu &lt;mhiramat@kernel.org&gt;
Signed-off-by: Steven Rostedt (VMware) &lt;rostedt@goodmis.org&gt;
Signed-off-by: Greg Kroah-Hartman &lt;gregkh@linuxfoundation.org&gt;

</content>
</entry>
<entry>
<title>kbuild: fix CONFIG_CC_CAN_LINK(_STATIC) for cross-compilation with Clang</title>
<updated>2020-07-01T15:57:45Z</updated>
<author>
<name>Masahiro Yamada</name>
<email>masahiroy@kernel.org</email>
</author>
<published>2020-06-30T15:06:24Z</published>
<link rel='alternate' type='text/html' href='https://git.stealer.net/cgit.cgi/user/sven/linux.git/commit/?id=b816b3db15f68690ee72a4a414624f8e82942b25'/>
<id>urn:sha1:b816b3db15f68690ee72a4a414624f8e82942b25</id>
<content type='text'>
scripts/cc-can-link.sh tests if the compiler can link userspace
programs.

When $(CC) is GCC, it is checked against the target architecture
because the toolchain prefix is specified as a part of $(CC).

When $(CC) is Clang, it is checked against the host architecture
because --target option is missing.

Pass $(CLANG_FLAGS) to scripts/cc-can-link.sh to evaluate the link
capability for the target architecture.

Signed-off-by: Masahiro Yamada &lt;masahiroy@kernel.org&gt;
Reviewed-by: Nathan Chancellor &lt;natechancellor@gmail.com&gt;
</content>
</entry>
<entry>
<title>Merge tag 'kbuild-v5.8-2' of git://git.kernel.org/pub/scm/linux/kernel/git/masahiroy/linux-kbuild</title>
<updated>2020-06-13T20:29:16Z</updated>
<author>
<name>Linus Torvalds</name>
<email>torvalds@linux-foundation.org</email>
</author>
<published>2020-06-13T20:29:16Z</published>
<link rel='alternate' type='text/html' href='https://git.stealer.net/cgit.cgi/user/sven/linux.git/commit/?id=6adc19fd13f11883c44df67b551cf8201e6bba1d'/>
<id>urn:sha1:6adc19fd13f11883c44df67b551cf8201e6bba1d</id>
<content type='text'>
Pull more Kbuild updates from Masahiro Yamada:

 - fix build rules in binderfs sample

 - fix build errors when Kbuild recurses to the top Makefile

 - covert '---help---' in Kconfig to 'help'

* tag 'kbuild-v5.8-2' of git://git.kernel.org/pub/scm/linux/kernel/git/masahiroy/linux-kbuild:
  treewide: replace '---help---' in Kconfig files with 'help'
  kbuild: fix broken builds because of GZIP,BZIP2,LZOP variables
  samples: binderfs: really compile this sample and fix build issues
</content>
</entry>
<entry>
<title>treewide: replace '---help---' in Kconfig files with 'help'</title>
<updated>2020-06-13T16:57:21Z</updated>
<author>
<name>Masahiro Yamada</name>
<email>masahiroy@kernel.org</email>
</author>
<published>2020-06-13T16:50:22Z</published>
<link rel='alternate' type='text/html' href='https://git.stealer.net/cgit.cgi/user/sven/linux.git/commit/?id=a7f7f6248d9740d710fd6bd190293fe5e16410ac'/>
<id>urn:sha1:a7f7f6248d9740d710fd6bd190293fe5e16410ac</id>
<content type='text'>
Since commit 84af7a6194e4 ("checkpatch: kconfig: prefer 'help' over
'---help---'"), the number of '---help---' has been gradually
decreasing, but there are still more than 2400 instances.

This commit finishes the conversion. While I touched the lines,
I also fixed the indentation.

There are a variety of indentation styles found.

  a) 4 spaces + '---help---'
  b) 7 spaces + '---help---'
  c) 8 spaces + '---help---'
  d) 1 space + 1 tab + '---help---'
  e) 1 tab + '---help---'    (correct indentation)
  f) 1 tab + 1 space + '---help---'
  g) 1 tab + 2 spaces + '---help---'

In order to convert all of them to 1 tab + 'help', I ran the
following commend:

  $ find . -name 'Kconfig*' | xargs sed -i 's/^[[:space:]]*---help---/\thelp/'

Signed-off-by: Masahiro Yamada &lt;masahiroy@kernel.org&gt;
</content>
</entry>
<entry>
<title>Merge tag 'notifications-20200601' of git://git.kernel.org/pub/scm/linux/kernel/git/dhowells/linux-fs</title>
<updated>2020-06-13T16:56:21Z</updated>
<author>
<name>Linus Torvalds</name>
<email>torvalds@linux-foundation.org</email>
</author>
<published>2020-06-13T16:56:21Z</published>
<link rel='alternate' type='text/html' href='https://git.stealer.net/cgit.cgi/user/sven/linux.git/commit/?id=6c3297841472b4e53e22e53826eea9e483d993e5'/>
<id>urn:sha1:6c3297841472b4e53e22e53826eea9e483d993e5</id>
<content type='text'>
Pull notification queue from David Howells:
 "This adds a general notification queue concept and adds an event
  source for keys/keyrings, such as linking and unlinking keys and
  changing their attributes.

  Thanks to Debarshi Ray, we do have a pull request to use this to fix a
  problem with gnome-online-accounts - as mentioned last time:

     https://gitlab.gnome.org/GNOME/gnome-online-accounts/merge_requests/47

  Without this, g-o-a has to constantly poll a keyring-based kerberos
  cache to find out if kinit has changed anything.

  [ There are other notification pending: mount/sb fsinfo notifications
    for libmount that Karel Zak and Ian Kent have been working on, and
    Christian Brauner would like to use them in lxc, but let's see how
    this one works first ]

  LSM hooks are included:

   - A set of hooks are provided that allow an LSM to rule on whether or
     not a watch may be set. Each of these hooks takes a different
     "watched object" parameter, so they're not really shareable. The
     LSM should use current's credentials. [Wanted by SELinux &amp; Smack]

   - A hook is provided to allow an LSM to rule on whether or not a
     particular message may be posted to a particular queue. This is
     given the credentials from the event generator (which may be the
     system) and the watch setter. [Wanted by Smack]

  I've provided SELinux and Smack with implementations of some of these
  hooks.

  WHY
  ===

  Key/keyring notifications are desirable because if you have your
  kerberos tickets in a file/directory, your Gnome desktop will monitor
  that using something like fanotify and tell you if your credentials
  cache changes.

  However, we also have the ability to cache your kerberos tickets in
  the session, user or persistent keyring so that it isn't left around
  on disk across a reboot or logout. Keyrings, however, cannot currently
  be monitored asynchronously, so the desktop has to poll for it - not
  so good on a laptop. This facility will allow the desktop to avoid the
  need to poll.

  DESIGN DECISIONS
  ================

   - The notification queue is built on top of a standard pipe. Messages
     are effectively spliced in. The pipe is opened with a special flag:

        pipe2(fds, O_NOTIFICATION_PIPE);

     The special flag has the same value as O_EXCL (which doesn't seem
     like it will ever be applicable in this context)[?]. It is given up
     front to make it a lot easier to prohibit splice&amp;co from accessing
     the pipe.

     [?] Should this be done some other way?  I'd rather not use up a new
         O_* flag if I can avoid it - should I add a pipe3() system call
         instead?

     The pipe is then configured::

        ioctl(fds[1], IOC_WATCH_QUEUE_SET_SIZE, queue_depth);
        ioctl(fds[1], IOC_WATCH_QUEUE_SET_FILTER, &amp;filter);

     Messages are then read out of the pipe using read().

   - It should be possible to allow write() to insert data into the
     notification pipes too, but this is currently disabled as the
     kernel has to be able to insert messages into the pipe *without*
     holding pipe-&gt;mutex and the code to make this work needs careful
     auditing.

   - sendfile(), splice() and vmsplice() are disabled on notification
     pipes because of the pipe-&gt;mutex issue and also because they
     sometimes want to revert what they just did - but one or more
     notification messages might've been interleaved in the ring.

   - The kernel inserts messages with the wait queue spinlock held. This
     means that pipe_read() and pipe_write() have to take the spinlock
     to update the queue pointers.

   - Records in the buffer are binary, typed and have a length so that
     they can be of varying size.

     This allows multiple heterogeneous sources to share a common
     buffer; there are 16 million types available, of which I've used
     just a few, so there is scope for others to be used. Tags may be
     specified when a watchpoint is created to help distinguish the
     sources.

   - Records are filterable as types have up to 256 subtypes that can be
     individually filtered. Other filtration is also available.

   - Notification pipes don't interfere with each other; each may be
     bound to a different set of watches. Any particular notification
     will be copied to all the queues that are currently watching for it
     - and only those that are watching for it.

   - When recording a notification, the kernel will not sleep, but will
     rather mark a queue as having lost a message if there's
     insufficient space. read() will fabricate a loss notification
     message at an appropriate point later.

   - The notification pipe is created and then watchpoints are attached
     to it, using one of:

        keyctl_watch_key(KEY_SPEC_SESSION_KEYRING, fds[1], 0x01);
        watch_mount(AT_FDCWD, "/", 0, fd, 0x02);
        watch_sb(AT_FDCWD, "/mnt", 0, fd, 0x03);

     where in both cases, fd indicates the queue and the number after is
     a tag between 0 and 255.

   - Watches are removed if either the notification pipe is destroyed or
     the watched object is destroyed. In the latter case, a message will
     be generated indicating the enforced watch removal.

  Things I want to avoid:

   - Introducing features that make the core VFS dependent on the
     network stack or networking namespaces (ie. usage of netlink).

   - Dumping all this stuff into dmesg and having a daemon that sits
     there parsing the output and distributing it as this then puts the
     responsibility for security into userspace and makes handling
     namespaces tricky. Further, dmesg might not exist or might be
     inaccessible inside a container.

   - Letting users see events they shouldn't be able to see.

  TESTING AND MANPAGES
  ====================

   - The keyutils tree has a pipe-watch branch that has keyctl commands
     for making use of notifications. Proposed manual pages can also be
     found on this branch, though a couple of them really need to go to
     the main manpages repository instead.

     If the kernel supports the watching of keys, then running "make
     test" on that branch will cause the testing infrastructure to spawn
     a monitoring process on the side that monitors a notifications pipe
     for all the key/keyring changes induced by the tests and they'll
     all be checked off to make sure they happened.

        https://git.kernel.org/pub/scm/linux/kernel/git/dhowells/keyutils.git/log/?h=pipe-watch

   - A test program is provided (samples/watch_queue/watch_test) that
     can be used to monitor for keyrings, mount and superblock events.
     Information on the notifications is simply logged to stdout"

* tag 'notifications-20200601' of git://git.kernel.org/pub/scm/linux/kernel/git/dhowells/linux-fs:
  smack: Implement the watch_key and post_notification hooks
  selinux: Implement the watch_key security hook
  keys: Make the KEY_NEED_* perms an enum rather than a mask
  pipe: Add notification lossage handling
  pipe: Allow buffers to be marked read-whole-or-error for notifications
  Add sample notification program
  watch_queue: Add a key/keyring notification facility
  security: Add hooks to rule on setting a watch
  pipe: Add general notification queue support
  pipe: Add O_NOTIFICATION_PIPE
  security: Add a hook for the point of notification insertion
  uapi: General notification queue definitions
</content>
</entry>
<entry>
<title>Rebase locking/kcsan to locking/urgent</title>
<updated>2020-06-11T18:02:46Z</updated>
<author>
<name>Thomas Gleixner</name>
<email>tglx@linutronix.de</email>
</author>
<published>2020-06-11T18:02:46Z</published>
<link rel='alternate' type='text/html' href='https://git.stealer.net/cgit.cgi/user/sven/linux.git/commit/?id=37d1a04b13a6d2fec91a6813fc034947a27db034'/>
<id>urn:sha1:37d1a04b13a6d2fec91a6813fc034947a27db034</id>
<content type='text'>
Merge the state of the locking kcsan branch before the read/write_once()
and the atomics modifications got merged.

Squash the fallout of the rebase on top of the read/write once and atomic
fallback work into the merge. The history of the original branch is
preserved in tag locking-kcsan-2020-06-02.

Signed-off-by: Thomas Gleixner &lt;tglx@linutronix.de&gt;
</content>
</entry>
<entry>
<title>Merge branch 'rwonce/rework' of git://git.kernel.org/pub/scm/linux/kernel/git/will/linux</title>
<updated>2020-06-10T21:46:54Z</updated>
<author>
<name>Linus Torvalds</name>
<email>torvalds@linux-foundation.org</email>
</author>
<published>2020-06-10T21:46:54Z</published>
<link rel='alternate' type='text/html' href='https://git.stealer.net/cgit.cgi/user/sven/linux.git/commit/?id=4152d146ee2169653297e03b9fa2e0f476923959'/>
<id>urn:sha1:4152d146ee2169653297e03b9fa2e0f476923959</id>
<content type='text'>
Pull READ/WRITE_ONCE rework from Will Deacon:
 "This the READ_ONCE rework I've been working on for a while, which
  bumps the minimum GCC version and improves code-gen on arm64 when
  stack protector is enabled"

[ Side note: I'm _really_ tempted to raise the minimum gcc version to
  4.9, so that we can just say that we require _Generic() support.

  That would allow us to more cleanly handle a lot of the cases where we
  depend on very complex macros with 'sizeof' or __builtin_choose_expr()
  with __builtin_types_compatible_p() etc.

  This branch has a workaround for sparse not handling _Generic(),
  either, but that was already fixed in the sparse development branch,
  so it's really just gcc-4.9 that we'd require.   - Linus ]

* 'rwonce/rework' of git://git.kernel.org/pub/scm/linux/kernel/git/will/linux:
  compiler_types.h: Use unoptimized __unqual_scalar_typeof for sparse
  compiler_types.h: Optimize __unqual_scalar_typeof compilation time
  compiler.h: Enforce that READ_ONCE_NOCHECK() access size is sizeof(long)
  compiler-types.h: Include naked type in __pick_integer_type() match
  READ_ONCE: Fix comment describing 2x32-bit atomicity
  gcov: Remove old GCC 3.4 support
  arm64: barrier: Use '__unqual_scalar_typeof' for acquire/release macros
  locking/barriers: Use '__unqual_scalar_typeof' for load-acquire macros
  READ_ONCE: Drop pointer qualifiers when reading from scalar types
  READ_ONCE: Enforce atomicity for {READ,WRITE}_ONCE() memory accesses
  READ_ONCE: Simplify implementations of {READ,WRITE}_ONCE()
  arm64: csum: Disable KASAN for do_csum()
  fault_inject: Don't rely on "return value" from WRITE_ONCE()
  net: tls: Avoid assigning 'const' pointer to non-const pointer
  netfilter: Avoid assigning 'const' pointer to non-const pointer
  compiler/gcc: Raise minimum GCC version for kernel builds to 4.8
</content>
</entry>
<entry>
<title>mm: don't include asm/pgtable.h if linux/mm.h is already included</title>
<updated>2020-06-09T16:39:13Z</updated>
<author>
<name>Mike Rapoport</name>
<email>rppt@linux.ibm.com</email>
</author>
<published>2020-06-09T04:32:33Z</published>
<link rel='alternate' type='text/html' href='https://git.stealer.net/cgit.cgi/user/sven/linux.git/commit/?id=e31cf2f4ca422ac9b14ecc4a1295b8977a20f812'/>
<id>urn:sha1:e31cf2f4ca422ac9b14ecc4a1295b8977a20f812</id>
<content type='text'>
Patch series "mm: consolidate definitions of page table accessors", v2.

The low level page table accessors (pXY_index(), pXY_offset()) are
duplicated across all architectures and sometimes more than once.  For
instance, we have 31 definition of pgd_offset() for 25 supported
architectures.

Most of these definitions are actually identical and typically it boils
down to, e.g.

static inline unsigned long pmd_index(unsigned long address)
{
        return (address &gt;&gt; PMD_SHIFT) &amp; (PTRS_PER_PMD - 1);
}

static inline pmd_t *pmd_offset(pud_t *pud, unsigned long address)
{
        return (pmd_t *)pud_page_vaddr(*pud) + pmd_index(address);
}

These definitions can be shared among 90% of the arches provided
XYZ_SHIFT, PTRS_PER_XYZ and xyz_page_vaddr() are defined.

For architectures that really need a custom version there is always
possibility to override the generic version with the usual ifdefs magic.

These patches introduce include/linux/pgtable.h that replaces
include/asm-generic/pgtable.h and add the definitions of the page table
accessors to the new header.

This patch (of 12):

The linux/mm.h header includes &lt;asm/pgtable.h&gt; to allow inlining of the
functions involving page table manipulations, e.g.  pte_alloc() and
pmd_alloc().  So, there is no point to explicitly include &lt;asm/pgtable.h&gt;
in the files that include &lt;linux/mm.h&gt;.

The include statements in such cases are remove with a simple loop:

	for f in $(git grep -l "include &lt;linux/mm.h&gt;") ; do
		sed -i -e '/include &lt;asm\/pgtable.h&gt;/ d' $f
	done

Signed-off-by: Mike Rapoport &lt;rppt@linux.ibm.com&gt;
Signed-off-by: Andrew Morton &lt;akpm@linux-foundation.org&gt;
Cc: Arnd Bergmann &lt;arnd@arndb.de&gt;
Cc: Borislav Petkov &lt;bp@alien8.de&gt;
Cc: Brian Cain &lt;bcain@codeaurora.org&gt;
Cc: Catalin Marinas &lt;catalin.marinas@arm.com&gt;
Cc: Chris Zankel &lt;chris@zankel.net&gt;
Cc: "David S. Miller" &lt;davem@davemloft.net&gt;
Cc: Geert Uytterhoeven &lt;geert@linux-m68k.org&gt;
Cc: Greentime Hu &lt;green.hu@gmail.com&gt;
Cc: Greg Ungerer &lt;gerg@linux-m68k.org&gt;
Cc: Guan Xuetao &lt;gxt@pku.edu.cn&gt;
Cc: Guo Ren &lt;guoren@kernel.org&gt;
Cc: Heiko Carstens &lt;heiko.carstens@de.ibm.com&gt;
Cc: Helge Deller &lt;deller@gmx.de&gt;
Cc: Ingo Molnar &lt;mingo@redhat.com&gt;
Cc: Ley Foon Tan &lt;ley.foon.tan@intel.com&gt;
Cc: Mark Salter &lt;msalter@redhat.com&gt;
Cc: Matthew Wilcox &lt;willy@infradead.org&gt;
Cc: Matt Turner &lt;mattst88@gmail.com&gt;
Cc: Max Filippov &lt;jcmvbkbc@gmail.com&gt;
Cc: Michael Ellerman &lt;mpe@ellerman.id.au&gt;
Cc: Michal Simek &lt;monstr@monstr.eu&gt;
Cc: Mike Rapoport &lt;rppt@kernel.org&gt;
Cc: Nick Hu &lt;nickhu@andestech.com&gt;
Cc: Paul Walmsley &lt;paul.walmsley@sifive.com&gt;
Cc: Richard Weinberger &lt;richard@nod.at&gt;
Cc: Rich Felker &lt;dalias@libc.org&gt;
Cc: Russell King &lt;linux@armlinux.org.uk&gt;
Cc: Stafford Horne &lt;shorne@gmail.com&gt;
Cc: Thomas Bogendoerfer &lt;tsbogend@alpha.franken.de&gt;
Cc: Thomas Gleixner &lt;tglx@linutronix.de&gt;
Cc: Tony Luck &lt;tony.luck@intel.com&gt;
Cc: Vincent Chen &lt;deanbo422@gmail.com&gt;
Cc: Vineet Gupta &lt;vgupta@synopsys.com&gt;
Cc: Will Deacon &lt;will@kernel.org&gt;
Cc: Yoshinori Sato &lt;ysato@users.sourceforge.jp&gt;
Link: http://lkml.kernel.org/r/20200514170327.31389-1-rppt@kernel.org
Link: http://lkml.kernel.org/r/20200514170327.31389-2-rppt@kernel.org
Signed-off-by: Linus Torvalds &lt;torvalds@linux-foundation.org&gt;
</content>
</entry>
<entry>
<title>kernel/sysctl: support setting sysctl parameters from kernel command line</title>
<updated>2020-06-08T18:05:56Z</updated>
<author>
<name>Vlastimil Babka</name>
<email>vbabka@suse.cz</email>
</author>
<published>2020-06-08T04:40:24Z</published>
<link rel='alternate' type='text/html' href='https://git.stealer.net/cgit.cgi/user/sven/linux.git/commit/?id=3db978d480e2843979a2b56f2f7da726f2b295b2'/>
<id>urn:sha1:3db978d480e2843979a2b56f2f7da726f2b295b2</id>
<content type='text'>
Patch series "support setting sysctl parameters from kernel command line", v3.

This series adds support for something that seems like many people
always wanted but nobody added it yet, so here's the ability to set
sysctl parameters via kernel command line options in the form of
sysctl.vm.something=1

The important part is Patch 1.  The second, not so important part is an
attempt to clean up legacy one-off parameters that do the same thing as
a sysctl.  I don't want to remove them completely for compatibility
reasons, but with generic sysctl support the idea is to remove the
one-off param handlers and treat the parameters as aliases for the
sysctl variants.

I have identified several parameters that mention sysctl counterparts in
Documentation/admin-guide/kernel-parameters.txt but there might be more.
The conversion also has varying level of success:

 - numa_zonelist_order is converted in Patch 2 together with adding the
   necessary infrastructure. It's easy as it doesn't really do anything
   but warn on deprecated value these days.

 - hung_task_panic is converted in Patch 3, but there's a downside that
   now it only accepts 0 and 1, while previously it was any integer
   value

 - nmi_watchdog maps to two sysctls nmi_watchdog and hardlockup_panic,
   so there's no straighforward conversion possible

 - traceoff_on_warning is a flag without value and it would be required
   to handle that somehow in the conversion infractructure, which seems
   pointless for a single flag

This patch (of 5):

A recently proposed patch to add vm_swappiness command line parameter in
addition to existing sysctl [1] made me wonder why we don't have a
general support for passing sysctl parameters via command line.

Googling found only somebody else wondering the same [2], but I haven't
found any prior discussion with reasons why not to do this.

Settings the vm_swappiness issue aside (the underlying issue might be
solved in a different way), quick search of kernel-parameters.txt shows
there are already some that exist as both sysctl and kernel parameter -
hung_task_panic, nmi_watchdog, numa_zonelist_order, traceoff_on_warning.

A general mechanism would remove the need to add more of those one-offs
and might be handy in situations where configuration by e.g.
/etc/sysctl.d/ is impractical.

Hence, this patch adds a new parse_args() pass that looks for parameters
prefixed by 'sysctl.' and tries to interpret them as writes to the
corresponding sys/ files using an temporary in-kernel procfs mount.
This mechanism was suggested by Eric W.  Biederman [3], as it handles
all dynamically registered sysctl tables, even though we don't handle
modular sysctls.  Errors due to e.g.  invalid parameter name or value
are reported in the kernel log.

The processing is hooked right before the init process is loaded, as
some handlers might be more complicated than simple setters and might
need some subsystems to be initialized.  At the moment the init process
can be started and eventually execute a process writing to /proc/sys/
then it should be also fine to do that from the kernel.

Sysctls registered later on module load time are not set by this
mechanism - it's expected that in such scenarios, setting sysctl values
from userspace is practical enough.

[1] https://lore.kernel.org/r/BL0PR02MB560167492CA4094C91589930E9FC0@BL0PR02MB5601.namprd02.prod.outlook.com/
[2] https://unix.stackexchange.com/questions/558802/how-to-set-sysctl-using-kernel-command-line-parameter
[3] https://lore.kernel.org/r/87bloj2skm.fsf@x220.int.ebiederm.org/

Signed-off-by: Vlastimil Babka &lt;vbabka@suse.cz&gt;
Signed-off-by: Andrew Morton &lt;akpm@linux-foundation.org&gt;
Reviewed-by: Luis Chamberlain &lt;mcgrof@kernel.org&gt;
Reviewed-by: Masami Hiramatsu &lt;mhiramat@kernel.org&gt;
Acked-by: Kees Cook &lt;keescook@chromium.org&gt;
Acked-by: Michal Hocko &lt;mhocko@suse.com&gt;
Cc: Iurii Zaikin &lt;yzaikin@google.com&gt;
Cc: Ivan Teterevkov &lt;ivan.teterevkov@nutanix.com&gt;
Cc: Michal Hocko &lt;mhocko@kernel.org&gt;
Cc: David Rientjes &lt;rientjes@google.com&gt;
Cc: Matthew Wilcox &lt;willy@infradead.org&gt;
Cc: "Eric W . Biederman" &lt;ebiederm@xmission.com&gt;
Cc: "Guilherme G . Piccoli" &lt;gpiccoli@canonical.com&gt;
Cc: Alexey Dobriyan &lt;adobriyan@gmail.com&gt;
Cc: Thomas Gleixner &lt;tglx@linutronix.de&gt;
Cc: Greg Kroah-Hartman &lt;gregkh@linuxfoundation.org&gt;
Cc: Christian Brauner &lt;christian.brauner@ubuntu.com&gt;
Link: http://lkml.kernel.org/r/20200427180433.7029-1-vbabka@suse.cz
Link: http://lkml.kernel.org/r/20200427180433.7029-2-vbabka@suse.cz
Signed-off-by: Linus Torvalds &lt;torvalds@linux-foundation.org&gt;
</content>
</entry>
<entry>
<title>Merge tag 'kbuild-v5.8' of git://git.kernel.org/pub/scm/linux/kernel/git/masahiroy/linux-kbuild</title>
<updated>2020-06-06T19:00:25Z</updated>
<author>
<name>Linus Torvalds</name>
<email>torvalds@linux-foundation.org</email>
</author>
<published>2020-06-06T19:00:25Z</published>
<link rel='alternate' type='text/html' href='https://git.stealer.net/cgit.cgi/user/sven/linux.git/commit/?id=cff11abeca78aa782378401ca2800bd2194aa14e'/>
<id>urn:sha1:cff11abeca78aa782378401ca2800bd2194aa14e</id>
<content type='text'>
Pull Kbuild updates from Masahiro Yamada:

 - fix warnings in 'make clean' for ARCH=um, hexagon, h8300, unicore32

 - ensure to rebuild all objects when the compiler is upgraded

 - exclude system headers from dependency tracking and fixdep processing

 - fix potential bit-size mismatch between the kernel and BPF user-mode
   helper

 - add the new syntax 'userprogs' to build user-space programs for the
   target architecture (the same arch as the kernel)

 - compile user-space sample code under samples/ for the target arch
   instead of the host arch

 - make headers_install fail if a CONFIG option is leaked to user-space

 - sanitize the output format of scripts/checkstack.pl

 - handle ARM 'push' instruction in scripts/checkstack.pl

 - error out before modpost if a module name conflict is found

 - error out when multiple directories are passed to M= because this
   feature is broken for a long time

 - add CONFIG_DEBUG_INFO_COMPRESSED to support compressed debug info

 - a lot of cleanups of modpost

 - dump vmlinux symbols out into vmlinux.symvers, and reuse it in the
   second pass of modpost

 - do not run the second pass of modpost if nothing in modules is
   updated

 - install modules.builtin(.modinfo) by 'make install' as well as by
   'make modules_install' because it is useful even when
   CONFIG_MODULES=n

 - add new command line variables, GZIP, BZIP2, LZOP, LZMA, LZ4, and XZ
   to allow users to use alternatives such as pigz, pbzip2, etc.

* tag 'kbuild-v5.8' of git://git.kernel.org/pub/scm/linux/kernel/git/masahiroy/linux-kbuild: (96 commits)
  kbuild: add variables for compression tools
  Makefile: install modules.builtin even if CONFIG_MODULES=n
  mksysmap: Fix the mismatch of '.L' symbols in System.map
  kbuild: doc: rename LDFLAGS to KBUILD_LDFLAGS
  modpost: change elf_info-&gt;size to size_t
  modpost: remove is_vmlinux() helper
  modpost: strip .o from modname before calling new_module()
  modpost: set have_vmlinux in new_module()
  modpost: remove mod-&gt;skip struct member
  modpost: add mod-&gt;is_vmlinux struct member
  modpost: remove is_vmlinux() call in check_for_{gpl_usage,unused}()
  modpost: remove mod-&gt;is_dot_o struct member
  modpost: move -d option in scripts/Makefile.modpost
  modpost: remove -s option
  modpost: remove get_next_text() and make {grab,release_}file static
  modpost: use read_text_file() and get_line() for reading text files
  modpost: avoid false-positive file open error
  modpost: fix potential mmap'ed file overrun in get_src_version()
  modpost: add read_text_file() and get_line() helpers
  modpost: do not call get_modinfo() for vmlinux(.o)
  ...
</content>
</entry>
</feed>
