linux.git/arch/m68k/kernel, branch v5.9

treewide: Use fallthrough pseudo-keyword

2020-08-23T22:36:59+00:00

Replace the existing /* fall through */ comments and its variants with
the new pseudo-keyword macro fallthrough[1]. Also, remove unnecessary
fall-through markings when it is the case.

[1] https://www.kernel.org/doc/html/v5.7/process/deprecated.html?highlight=fallthrough#implicit-switch-case-fall-through

Signed-off-by: Gustavo A. R. Silva

all arch: remove system call sys_sysctl

2020-08-15T02:56:56+00:00

Since commit 61a47c1ad3a4dc ("sysctl: Remove the sysctl system call"),
sys_sysctl is actually unavailable: any input can only return an error.

We have been warning about people using the sysctl system call for years
and believe there are no more users.  Even if there are users of this
interface if they have not complained or fixed their code by now they
probably are not going to, so there is no point in warning them any
longer.

So completely remove sys_sysctl on all architectures.

[nixiaoming@huawei.com: s390: fix build error for sys_call_table_emu]
 Link: http://lkml.kernel.org/r/20200618141426.16884-1-nixiaoming@huawei.com

Signed-off-by: Xiaoming Ni 
Signed-off-by: Andrew Morton 
Acked-by: Will Deacon 		[arm/arm64]
Acked-by: "Eric W. Biederman" 
Cc: Aleksa Sarai 
Cc: Alexander Shishkin 
Cc: Al Viro 
Cc: Andi Kleen 
Cc: Andrew Morton 
Cc: Andy Lutomirski 
Cc: Arnaldo Carvalho de Melo 
Cc: Arnd Bergmann 
Cc: Benjamin Herrenschmidt 
Cc: Bin Meng 
Cc: Borislav Petkov 
Cc: Brian Gerst 
Cc: Catalin Marinas 
Cc: chenzefeng 
Cc: Christian Borntraeger 
Cc: Christian Brauner 
Cc: Chris Zankel 
Cc: David Howells 
Cc: David S. Miller 
Cc: Diego Elio Pettenò 
Cc: Dmitry Vyukov 
Cc: Dominik Brodowski 
Cc: Fenghua Yu 
Cc: Geert Uytterhoeven 
Cc: Heiko Carstens 
Cc: Helge Deller 
Cc: "H. Peter Anvin" 
Cc: Ingo Molnar 
Cc: Iurii Zaikin 
Cc: Ivan Kokshaysky 
Cc: James Bottomley 
Cc: Jens Axboe 
Cc: Jiri Olsa 
Cc: Kars de Jong 
Cc: Kees Cook 
Cc: Krzysztof Kozlowski 
Cc: Luis Chamberlain 
Cc: Marco Elver 
Cc: Mark Rutland 
Cc: Martin K. Petersen 
Cc: Masahiro Yamada 
Cc: Matt Turner 
Cc: Max Filippov 
Cc: Michael Ellerman 
Cc: Michal Simek 
Cc: Miklos Szeredi 
Cc: Minchan Kim 
Cc: Namhyung Kim 
Cc: Naveen N. Rao 
Cc: Nick Piggin 
Cc: Oleg Nesterov 
Cc: Olof Johansson 
Cc: Paul Burton 
Cc: "Paul E. McKenney" 
Cc: Paul Mackerras 
Cc: Peter Zijlstra (Intel) 
Cc: Randy Dunlap 
Cc: Ravi Bangoria 
Cc: Richard Henderson 
Cc: Rich Felker 
Cc: Russell King 
Cc: Sami Tolvanen 
Cc: Sargun Dhillon 
Cc: Stephen Rothwell 
Cc: Sudeep Holla 
Cc: Sven Schnelle 
Cc: Thiago Jung Bauermann 
Cc: Thomas Bogendoerfer 
Cc: Thomas Gleixner 
Cc: Tony Luck 
Cc: Vasily Gorbik 
Cc: Vlastimil Babka 
Cc: Yoshinori Sato 
Cc: Zhou Yanjie 
Link: http://lkml.kernel.org/r/20200616030734.87257-1-nixiaoming@huawei.com
Signed-off-by: Linus Torvalds

mm: remove unneeded includes of

2020-08-07T18:33:26+00:00

Patch series "mm: cleanup usage of "

Most architectures have very similar versions of pXd_alloc_one() and
pXd_free_one() for intermediate levels of page table.  These patches add
generic versions of these functions in  and enable
use of the generic functions where appropriate.

In addition, functions declared and defined in  headers are
used mostly by core mm and early mm initialization in arch and there is no
actual reason to have the  included all over the place.
The first patch in this series removes unneeded includes of


In the end it didn't work out as neatly as I hoped and moving
pXd_alloc_track() definitions to  would require
unnecessary changes to arches that have custom page table allocations, so
I've decided to move lib/ioremap.c to mm/ and make pgalloc-track.h local
to mm/.

This patch (of 8):

In most cases  header is required only for allocations of
page table memory.  Most of the .c files that include that header do not
use symbols declared in  and do not require that header.

As for the other header files that used to include , it is
possible to move that include into the .c file that actually uses symbols
from  and drop the include from the header file.

The process was somewhat automated using

	sed -i -E '/[<"]asm\/pgalloc\.h/d' \
                $(grep -L -w -f /tmp/xx \
                        $(git grep -E -l '[<"]asm/pgalloc\.h'))

where /tmp/xx contains all the symbols defined in
arch/*/include/asm/pgalloc.h.

[rppt@linux.ibm.com: fix powerpc warning]

Signed-off-by: Mike Rapoport 
Signed-off-by: Andrew Morton 
Reviewed-by: Pekka Enberg 
Acked-by: Geert Uytterhoeven 	[m68k]
Cc: Abdul Haleem 
Cc: Andy Lutomirski 
Cc: Arnd Bergmann 
Cc: Christophe Leroy 
Cc: Joerg Roedel 
Cc: Max Filippov 
Cc: Peter Zijlstra 
Cc: Satheesh Rajendran 
Cc: Stafford Horne 
Cc: Stephen Rothwell 
Cc: Steven Rostedt 
Cc: Joerg Roedel 
Cc: Matthew Wilcox 
Link: http://lkml.kernel.org/r/20200627143453.31835-1-rppt@kernel.org
Link: http://lkml.kernel.org/r/20200627143453.31835-2-rppt@kernel.org
Signed-off-by: Linus Torvalds

Merge tag 'close-range-v5.9' of git://git.kernel.org/pub/scm/linux/kernel/git/brauner/linux

2020-08-04T22:12:02+00:00

Pull close_range() implementation from Christian Brauner:
 "This adds the close_range() syscall. It allows to efficiently close a
  range of file descriptors up to all file descriptors of a calling
  task.

  This is coordinated with the FreeBSD folks which have copied our
  version of this syscall and in the meantime have already merged it in
  April 2019:

    https://reviews.freebsd.org/D21627
    https://svnweb.freebsd.org/base?view=revision&revision=359836

  The syscall originally came up in a discussion around the new mount
  API and making new file descriptor types cloexec by default. During
  this discussion, Al suggested the close_range() syscall.

  First, it helps to close all file descriptors of an exec()ing task.
  This can be done safely via (quoting Al's example from [1] verbatim):

        /* that exec is sensitive */
        unshare(CLONE_FILES);
        /* we don't want anything past stderr here */
        close_range(3, ~0U);
        execve(....);

  The code snippet above is one way of working around the problem that
  file descriptors are not cloexec by default. This is aggravated by the
  fact that we can't just switch them over without massively regressing
  userspace. For a whole class of programs having an in-kernel method of
  closing all file descriptors is very helpful (e.g. demons, service
  managers, programming language standard libraries, container managers
  etc.).

  Second, it allows userspace to avoid implementing closing all file
  descriptors by parsing through /proc//fd/* and calling close() on
  each file descriptor and other hacks. From looking at various
  large(ish) userspace code bases this or similar patterns are very
  common in service managers, container runtimes, and programming
  language runtimes/standard libraries such as Python or Rust.

  In addition, the syscall will also work for tasks that do not have
  procfs mounted and on kernels that do not have procfs support compiled
  in. In such situations the only way to make sure that all file
  descriptors are closed is to call close() on each file descriptor up
  to UINT_MAX or RLIMIT_NOFILE, OPEN_MAX trickery.

  Based on Linus' suggestion close_range() also comes with a new flag
  CLOSE_RANGE_UNSHARE to more elegantly handle file descriptor dropping
  right before exec. This would usually be expressed in the sequence:

        unshare(CLONE_FILES);
        close_range(3, ~0U);

  as pointed out by Linus it might be desirable to have this be a part
  of close_range() itself under a new flag CLOSE_RANGE_UNSHARE which
  gets especially handy when we're closing all file descriptors above a
  certain threshold.

  Test-suite as always included"

* tag 'close-range-v5.9' of git://git.kernel.org/pub/scm/linux/kernel/git/brauner/linux:
  tests: add CLOSE_RANGE_UNSHARE tests
  close_range: add CLOSE_RANGE_UNSHARE
  tests: add close_range() tests
  arch: wire-up close_range()
  open: add close_range()

Merge tag 'fork-v5.9' of git://git.kernel.org/pub/scm/linux/kernel/git/brauner/linux

2020-08-04T21:47:45+00:00

Pull fork cleanups from Christian Brauner:
 "This is cleanup series from when we reworked a chunk of the process
  creation paths in the kernel and switched to struct
  {kernel_}clone_args.

  High-level this does two main things:

   - Remove the double export of both do_fork() and _do_fork() where
     do_fork() used the incosistent legacy clone calling convention.

     Now we only export _do_fork() which is based on struct
     kernel_clone_args.

   - Remove the copy_thread_tls()/copy_thread() split making the
     architecture specific HAVE_COYP_THREAD_TLS config option obsolete.

  This switches all remaining architectures to select
  HAVE_COPY_THREAD_TLS and thus to the copy_thread_tls() calling
  convention. The current split makes the process creation codepaths
  more convoluted than they need to be. Each architecture has their own
  copy_thread() function unless it selects HAVE_COPY_THREAD_TLS then it
  has a copy_thread_tls() function.

  The split is not needed anymore nowadays, all architectures support
  CLONE_SETTLS but quite a few of them never bothered to select
  HAVE_COPY_THREAD_TLS and instead simply continued to use copy_thread()
  and use the old calling convention. Removing this split cleans up the
  process creation codepaths and paves the way for implementing clone3()
  on such architectures since it requires the copy_thread_tls() calling
  convention.

  After having made each architectures support copy_thread_tls() this
  series simply renames that function back to copy_thread(). It also
  switches all architectures that call do_fork() directly over to
  _do_fork() and the struct kernel_clone_args calling convention. This
  is a corollary of switching the architectures that did not yet support
  it over to copy_thread_tls() since do_fork() is conditional on not
  supporting copy_thread_tls() (Mostly because it lacks a separate
  argument for tls which is trivial to fix but there's no need for this
  function to exist.).

  The do_fork() removal is in itself already useful as it allows to to
  remove the export of both do_fork() and _do_fork() we currently have
  in favor of only _do_fork(). This has already been discussed back when
  we added clone3(). The legacy clone() calling convention is - as is
  probably well-known - somewhat odd:

    #
    # ABI hall of shame
    #
    config CLONE_BACKWARDS
    config CLONE_BACKWARDS2
    config CLONE_BACKWARDS3

  that is aggravated by the fact that some architectures such as sparc
  follow the CLONE_BACKWARDSx calling convention but don't really select
  the corresponding config option since they call do_fork() directly.

  So do_fork() enforces a somewhat arbitrary calling convention in the
  first place that doesn't really help the individual architectures that
  deviate from it. They can thus simply be switched to _do_fork()
  enforcing a single calling convention. (I really hope that any new
  architectures will __not__ try to implement their own calling
  conventions...)

  Most architectures already have made a similar switch (m68k comes to
  mind).

  Overall this removes more code than it adds even with a good portion
  of added comments. It simplifies a chunk of arch specific assembly
  either by moving the code into C or by simply rewriting the assembly.

  Architectures that have been touched in non-trivial ways have all been
  actually boot and stress tested: sparc and ia64 have been tested with
  Debian 9 images. They are the two architectures which have been
  touched the most. All non-trivial changes to architectures have seen
  acks from the relevant maintainers. nios2 with a custom built
  buildroot image. h8300 I couldn't get something bootable to test on
  but the changes have been fairly automatic and I'm sure we'll hear
  people yell if I broke something there.

  All other architectures that have been touched in trivial ways have
  been compile tested for each single patch of the series via git rebase
  -x "make ..." v5.8-rc2. arm{64} and x86{_64} have been boot tested
  even though they have just been trivially touched (removal of the
  HAVE_COPY_THREAD_TLS macro from their Kconfig) because well they are
  basically "core architectures" and since it is trivial to get your
  hands on a useable image"

* tag 'fork-v5.9' of git://git.kernel.org/pub/scm/linux/kernel/git/brauner/linux:
  arch: rename copy_thread_tls() back to copy_thread()
  arch: remove HAVE_COPY_THREAD_TLS
  unicore: switch to copy_thread_tls()
  sh: switch to copy_thread_tls()
  nds32: switch to copy_thread_tls()
  microblaze: switch to copy_thread_tls()
  hexagon: switch to copy_thread_tls()
  c6x: switch to copy_thread_tls()
  alpha: switch to copy_thread_tls()
  fork: remove do_fork()
  h8300: select HAVE_COPY_THREAD_TLS, switch to kernel_clone_args
  nios2: enable HAVE_COPY_THREAD_TLS, switch to kernel_clone_args
  ia64: enable HAVE_COPY_THREAD_TLS, switch to kernel_clone_args
  sparc: unconditionally enable HAVE_COPY_THREAD_TLS
  sparc: share process creation helpers between sparc and sparc64
  sparc64: enable HAVE_COPY_THREAD_TLS
  fork: fold legacy_clone_args_valid() into _do_fork()

Merge tag 'm68k-for-v5.9-tag1' of git://git.kernel.org/pub/scm/linux/kernel/git/geert/linux-m68k

2020-08-03T21:05:50+00:00

Pull m68k updates from Geert Uytterhoeven:

 - several Kbuild improvements

 - several Mac fixes

 - minor cleanups and fixes

 - defconfig updates

* tag 'm68k-for-v5.9-tag1' of git://git.kernel.org/pub/scm/linux/kernel/git/geert/linux-m68k:
  m68k: defconfig: Update defconfigs for v5.8-rc3
  m68k: Use CLEAN_FILES to clean up files
  m68k: mac: Improve IOP debug messages
  m68k: mac: Don't send uninitialized data in IOP message reply
  m68k: mac: Fix IOP status/control register writes
  m68k: mac: Don't send IOP message until channel is idle
  m68k: atari: Annotate dummy read in ROM port IO code as __maybe_unused
  m68k: Use sizeof_field() helper
  m68k: Pass -D options to KBUILD_CPPFLAGS instead of KBUILD_{A,C}FLAGS
  m68k: Optimize cc-option calls for cpuflags-y
  m68k: sun3: Descend to prom from arch/m68k/sun3
  m68k: Add arch/m68k/Kbuild

m68k: Use sizeof_field() helper

2020-07-13T09:39:13+00:00

Make use of the sizeof_field() helper instead of an open-coded version.

Signed-off-by: Gustavo A. R. Silva 
Link: https://lore.kernel.org/r/20200527133942.GA10408@embeddedor
Signed-off-by: Geert Uytterhoeven

arch: rename copy_thread_tls() back to copy_thread()

2020-07-04T21:41:37+00:00

Now that HAVE_COPY_THREAD_TLS has been removed, rename copy_thread_tls()
back simply copy_thread(). It's a simpler name, and doesn't imply that only
tls is copied here. This finishes an outstanding chunk of internal process
creation work since we've added clone3().

Cc: linux-arch@vger.kernel.org
Acked-by: Thomas Bogendoerfer A
Acked-by: Stafford Horne 
Acked-by: Greentime Hu 
Acked-by: Geert Uytterhoeven A
Reviewed-by: Kees Cook 
Signed-off-by: Christian Brauner

m68k: nommu: register start of the memory with memblock

2020-06-29T13:57:54+00:00

The m68k nommu setup code didn't register the beginning of the physical
memory with memblock because it was anyway occupied by the kernel. However,
commit fa3354e4ea39 ("mm: free_area_init: use maximal zone PFNs rather than
zone sizes") changed zones initialization to use memblock.memory to detect
the zone extents and this caused inconsistency between zone PFNs and the
actual PFNs:

BUG: Bad page state in process swapper  pfn:20165
page:41fe0ca0 refcount:0 mapcount:1 mapping:00000000 index:0x0 flags: 0x0()
raw: 00000000 00000100 00000122 00000000 00000000 00000000 00000000 00000000
page dumped because: nonzero mapcount
CPU: 0 PID: 1 Comm: swapper Not tainted 5.8.0-rc1-00001-g3a38f8a60c65-dirty #1
Stack from 404c9ebc:
        404c9ebc 4029ab28 4029ab28 40088470 41fe0ca0 40299e21 40299df1 404ba2a4
        00020165 00000000 41fd2c10 402c7ba0 41fd2c04 40088504 41fe0ca0 40299e21
        00000000 40088a12 41fe0ca0 41fe0ca4 0000020a 00000000 00000001 402ca000
        00000000 41fe0ca0 41fd2c10 41fd2c10 00000000 00000000 402b2388 00000001
        400a0934 40091056 404c9f44 404c9f44 40088db4 402c7ba0 00000001 41fd2c04
        41fe0ca0 41fd2000 41fe0ca0 40089e02 4026ecf4 40089e4e 41fe0ca0 ffffffff
Call Trace:
        [<40088470>] 0x40088470
 [<40088504>] 0x40088504
 [<40088a12>] 0x40088a12
 [<402ca000>] 0x402ca000
 [<400a0934>] 0x400a0934

Adjust the memory registration with memblock to include the beginning of
the physical memory and make sure that the area occupied by the kernel is
marked as reserved.

Signed-off-by: Mike Rapoport 
Signed-off-by: Greg Ungerer

fork: fold legacy_clone_args_valid() into _do_fork()

2020-06-22T12:38:38+00:00

This separate helper only existed to guarantee the mutual exclusivity of
CLONE_PIDFD and CLONE_PARENT_SETTID for legacy clone since CLONE_PIDFD
abuses the parent_tid field to return the pidfd. But we can actually handle
this uniformely thus removing the helper. For legacy clone we can detect
that CLONE_PIDFD is specified in conjunction with CLONE_PARENT_SETTID
because they will share the same memory which is invalid and for clone3()
setting the separate pidfd and parent_tid fields to the same memory is
bogus as well. So fold that helper directly into _do_fork() by detecting
this case.

Cc: Thomas Gleixner 
Cc: Ingo Molnar 
Cc: Al Viro 
Cc: Geert Uytterhoeven 
Cc: "Matthew Wilcox (Oracle)" 
Cc: "Peter Zijlstra (Intel)" 
Cc: linux-m68k@lists.linux-m68k.org
Cc: x86@kernel.org
Signed-off-by: Christian Brauner