1. 05 Jan, 2018 1 commit
  2. 02 Nov, 2017 1 commit
    • Greg Kroah-Hartman's avatar
      License cleanup: add SPDX GPL-2.0 license identifier to files with no license · b2441318
      Greg Kroah-Hartman authored
      Many source files in the tree are missing licensing information, which
      makes it harder for compliance tools to determine the correct license.
      
      By default all files without license information are under the default
      license of the kernel, which is GPL version 2.
      
      Update the files which contain no license information with the 'GPL-2.0'
      SPDX license identifier.  The SPDX identifier is a legally binding
      shorthand, which can be used instead of the full boiler plate text.
      
      This patch is based on work done by Thomas Gleixner and Kate Stewart and
      Philippe Ombredanne.
      
      How this work was done:
      
      Patches were generated and checked against linux-4.14-rc6 for a subset of
      the use cases:
       - file had no licensing information it it.
       - file was a */uapi/* one with no licensing information in it,
       - file was a */uapi/* one with existing licensing information,
      
      Further patches will be generated in subsequent months to fix up cases
      where non-standard license headers were used, and references to license
      had to be inferred by heuristics based on keywords.
      
      The analysis to determine which SPDX License Identifier to be applied to
      a file was done in a spreadsheet of side by side results from of the
      output of two independent scanners (ScanCode & Windriver) producing SPDX
      tag:value files created by Philippe Ombredanne.  Philippe prepared the
      base worksheet, and did an initial spot review of a few 1000 files.
      
      The 4.13 kernel was the starting point of the analysis with 60,537 files
      assessed.  Kate Stewart did a file by file comparison of the scanner
      results in the spreadsheet to determine which SPDX license identifier(s)
      to be applied to the file. She confirmed any determination that was not
      immediately clear with lawyers working with the Linux Foundation.
      
      Criteria used to select files for SPDX license identifier tagging was:
       - Files considered eligible had to be source code files.
       - Make and config files were included as candidates if they contained >5
         lines of source
       - File already had some variant of a license header in it (even if <5
         lines).
      
      All documentation files were explicitly excluded.
      
      The following heuristics were used to determine which SPDX license
      identifiers to apply.
      
       - when both scanners couldn't find any license traces, file was
         considered to have no license information in it, and the top level
         COPYING file license applied.
      
         For non */uapi/* files that summary was:
      
         SPDX license identifier                            # files
         ---------------------------------------------------|-------
         GPL-2.0                                              11139
      
         and resulted in the first patch in this series.
      
         If that file was a */uapi/* path one, it was "GPL-2.0 WITH
         Linux-syscall-note" otherwise it was "GPL-2.0".  Results of that was:
      
         SPDX license identifier                            # files
         ---------------------------------------------------|-------
         GPL-2.0 WITH Linux-syscall-note                        930
      
         and resulted in the second patch in this series.
      
       - if a file had some form of licensing information in it, and was one
         of the */uapi/* ones, it was denoted with the Linux-syscall-note if
         any GPL family license was found in the file or had no licensing in
         it (per prior point).  Results summary:
      
         SPDX license identifier                            # files
         ---------------------------------------------------|------
         GPL-2.0 WITH Linux-syscall-note                       270
         GPL-2.0+ WITH Linux-syscall-note                      169
         ((GPL-2.0 WITH Linux-syscall-note) OR BSD-2-Clause)    21
         ((GPL-2.0 WITH Linux-syscall-note) OR BSD-3-Clause)    17
         LGPL-2.1+ WITH Linux-syscall-note                      15
         GPL-1.0+ WITH Linux-syscall-note                       14
         ((GPL-2.0+ WITH Linux-syscall-note) OR BSD-3-Clause)    5
         LGPL-2.0+ WITH Linux-syscall-note                       4
         LGPL-2.1 WITH Linux-syscall-note                        3
         ((GPL-2.0 WITH Linux-syscall-note) OR MIT)              3
         ((GPL-2.0 WITH Linux-syscall-note) AND MIT)             1
      
         and that resulted in the third patch in this series.
      
       - when the two scanners agreed on the detected license(s), that became
         the concluded license(s).
      
       - when there was disagreement between the two scanners (one detected a
         license but the other didn't, or they both detected different
         licenses) a manual inspection of the file occurred.
      
       - In most cases a manual inspection of the information in the file
         resulted in a clear resolution of the license that should apply (and
         which scanner probably needed to revisit its heuristics).
      
       - When it was not immediately clear, the license identifier was
         confirmed with lawyers working with the Linux Foundation.
      
       - If there was any question as to the appropriate license identifier,
         the file was flagged for further research and to be revisited later
         in time.
      
      In total, over 70 hours of logged manual review was done on the
      spreadsheet to determine the SPDX license identifiers to apply to the
      source files by Kate, Philippe, Thomas and, in some cases, confirmation
      by lawyers working with the Linux Foundation.
      
      Kate also obtained a third independent scan of the 4.13 code base from
      FOSSology, and compared selected files where the other two scanners
      disagreed against that SPDX file, to see if there was new insights.  The
      Windriver scanner is based on an older version of FOSSology in part, so
      they are related.
      
      Thomas did random spot checks in about 500 files from the spreadsheets
      for the uapi headers and agreed with SPDX license identifier in the
      files he inspected. For the non-uapi files Thomas did random spot checks
      in about 15000 files.
      
      In initial set of patches against 4.14-rc6, 3 files were found to have
      copy/paste license identifier errors, and have been fixed to reflect the
      correct identifier.
      
      Additionally Philippe spent 10 hours this week doing a detailed manual
      inspection and review of the 12,461 patched files from the initial patch
      version early this week with:
       - a full scancode scan run, collecting the matched texts, detected
         license ids and scores
       - reviewing anything where there was a license detected (about 500+
         files) to ensure that the applied SPDX license was correct
       - reviewing anything where there was no detection but the patch license
         was not GPL-2.0 WITH Linux-syscall-note to ensure that the applied
         SPDX license was correct
      
      This produced a worksheet with 20 files needing minor correction.  This
      worksheet was then exported into 3 different .csv files for the
      different types of files to be modified.
      
      These .csv files were then reviewed by Greg.  Thomas wrote a script to
      parse the csv files and add the proper SPDX tag to the file, in the
      format that the file expected.  This script was further refined by Greg
      based on the output to detect more types of files automatically and to
      distinguish between header and source .c files (which need different
      comment types.)  Finally Greg ran the script using the .csv files to
      generate the patches.
      Reviewed-by: default avatarKate Stewart <kstewart@linuxfoundation.org>
      Reviewed-by: default avatarPhilippe Ombredanne <pombredanne@nexb.com>
      Reviewed-by: default avatarThomas Gleixner <tglx@linutronix.de>
      Signed-off-by: default avatarGreg Kroah-Hartman <gregkh@linuxfoundation.org>
      b2441318
  3. 25 Oct, 2017 1 commit
    • Mark Rutland's avatar
      locking/atomics: COCCINELLE/treewide: Convert trivial ACCESS_ONCE() patterns... · 6aa7de05
      Mark Rutland authored
      locking/atomics: COCCINELLE/treewide: Convert trivial ACCESS_ONCE() patterns to READ_ONCE()/WRITE_ONCE()
      
      Please do not apply this to mainline directly, instead please re-run the
      coccinelle script shown below and apply its output.
      
      For several reasons, it is desirable to use {READ,WRITE}_ONCE() in
      preference to ACCESS_ONCE(), and new code is expected to use one of the
      former. So far, there's been no reason to change most existing uses of
      ACCESS_ONCE(), as these aren't harmful, and changing them results in
      churn.
      
      However, for some features, the read/write distinction is critical to
      correct operation. To distinguish these cases, separate read/write
      accessors must be used. This patch migrates (most) remaining
      ACCESS_ONCE() instances to {READ,WRITE}_ONCE(), using the following
      coccinelle script:
      
      ----
      // Convert trivial ACCESS_ONCE() uses to equivalent READ_ONCE() and
      // WRITE_ONCE()
      
      // $ make coccicheck COCCI=/home/mark/once.cocci SPFLAGS="--include-headers" MODE=patch
      
      virtual patch
      
      @ depends on patch @
      expression E1, E2;
      @@
      
      - ACCESS_ONCE(E1) = E2
      + WRITE_ONCE(E1, E2)
      
      @ depends on patch @
      expression E;
      @@
      
      - ACCESS_ONCE(E)
      + READ_ONCE(E)
      ----
      Signed-off-by: default avatarMark Rutland <mark.rutland@arm.com>
      Signed-off-by: default avatarPaul E. McKenney <paulmck@linux.vnet.ibm.com>
      Cc: Linus Torvalds <torvalds@linux-foundation.org>
      Cc: Peter Zijlstra <peterz@infradead.org>
      Cc: Thomas Gleixner <tglx@linutronix.de>
      Cc: davem@davemloft.net
      Cc: linux-arch@vger.kernel.org
      Cc: mpe@ellerman.id.au
      Cc: shuah@kernel.org
      Cc: snitzer@redhat.com
      Cc: thor.thayer@linux.intel.com
      Cc: tj@kernel.org
      Cc: viro@zeniv.linux.org.uk
      Cc: will.deacon@arm.com
      Link: http://lkml.kernel.org/r/1508792849-3115-19-git-send-email-paulmck@linux.vnet.ibm.comSigned-off-by: default avatarIngo Molnar <mingo@kernel.org>
      6aa7de05
  4. 04 Sep, 2017 1 commit
  5. 02 Mar, 2017 1 commit
  6. 01 Feb, 2017 2 commits
  7. 12 Apr, 2015 1 commit
  8. 26 Jan, 2015 5 commits
  9. 10 Oct, 2014 1 commit
  10. 08 Aug, 2014 1 commit
  11. 07 Aug, 2014 16 commits
    • Ionut Alexa's avatar
    • Al Viro's avatar
      death to mnt_pinned · 3064c356
      Al Viro authored
      Rather than playing silly buggers with vfsmount refcounts, just have
      acct_on() ask fs/namespace.c for internal clone of file->f_path.mnt
      and replace it with said clone.  Then attach the pin to original
      vfsmount.  Voila - the clone will be alive until the file gets closed,
      making sure that underlying superblock remains active, etc., and
      we can drop the original vfsmount, so that it's not kept busy.
      If the file lives until the final mntput of the original vfsmount,
      we'll notice that there's an fs_pin (one in bsd_acct_struct that
      holds that file) and mnt_pin_kill() will take it out.  Since
      ->kill() is synchronous, we won't proceed past that point until
      these files are closed (and private clones of our vfsmount are
      gone), so we get the same ordering warranties we used to get.
      
      mnt_pin()/mnt_unpin()/->mnt_pinned is gone now, and good riddance -
      it never became usable outside of kernel/acct.c (and racy wrt
      umount even there).
      Signed-off-by: default avatarAl Viro <viro@zeniv.linux.org.uk>
      3064c356
    • Al Viro's avatar
      take fs_pin stuff to fs/* · efb170c2
      Al Viro authored
      Add a new field to fs_pin - kill(pin).  That's what umount and r/o remount
      will be calling for all pins attached to vfsmount and superblock resp.
      Called after bumping the refcount, so it won't go away under us.  Dropping
      the refcount is responsibility of the instance.  All generic stuff moved to
      fs/fs_pin.c; the next step will rip all the knowledge of kernel/acct.c from
      fs/super.c and fs/namespace.c.  After that - death to mnt_pin(); it was
      intended to be usable as generic mechanism for code that wants to attach
      objects to vfsmount, so that they would not make the sucker busy and
      would get killed on umount.  Never got it right; it remained acct.c-specific
      all along.  Now it's very close to being killable.
      Signed-off-by: default avatarAl Viro <viro@zeniv.linux.org.uk>
      efb170c2
    • Al Viro's avatar
      start carving bsd_acct_struct up · 1629d0eb
      Al Viro authored
      pull generic parts into struct fs_pin.  Eventually we want those
      to replace mnt_pin()/mnt_unpin() mess; that stuff will move to
      fs/*.
      Signed-off-by: default avatarAl Viro <viro@zeniv.linux.org.uk>
      1629d0eb
    • Al Viro's avatar
      acct: move mnt_pin() upwards. · 215748e6
      Al Viro authored
      Signed-off-by: default avatarAl Viro <viro@zeniv.linux.org.uk>
      215748e6
    • Al Viro's avatar
      make acct_kill() wait for file closing. · 17c0a5aa
      Al Viro authored
      Do actual closing of file via schedule_work().  And use
      __fput_sync() there.
      Signed-off-by: default avatarAl Viro <viro@zeniv.linux.org.uk>
      17c0a5aa
    • Al Viro's avatar
      acct: get rid of acct_lock for acct->count · 2798d4ce
      Al Viro authored
      * make acct->count atomic and acct freeing - rcu-delayed.
      * instead of grabbing acct_lock around the places where we take a reference,
      do that under rcu_read_lock() with atomic_long_inc_not_zero().
      * have the new acct locked before making ns->bacct point to it
      Signed-off-by: default avatarAl Viro <viro@zeniv.linux.org.uk>
      2798d4ce
    • Al Viro's avatar
      acct: get rid of acct_list · 215752fc
      Al Viro authored
      Put these suckers on per-vfsmount and per-superblock lists instead.
      Note: right now it's still acct_lock for everything, but that's
      going to change.
      Signed-off-by: default avatarAl Viro <viro@zeniv.linux.org.uk>
      215752fc
    • Al Viro's avatar
      acct: simplify check_free_space() · 54a4d58a
      Al Viro authored
      a) file can't be NULL
      b) file can't be changed under us
      c) all writes are serialized by acct->lock; no need to mess with
      spinlock there.
      Signed-off-by: default avatarAl Viro <viro@zeniv.linux.org.uk>
      54a4d58a
    • Al Viro's avatar
      acct: new lifetime rules · b8f00e6b
      Al Viro authored
      Do not reuse bsd_acct_struct after closing the damn thing.
      Structure lifetime is controlled by refcount now.  We also
      have a mutex in there, held over closing and writing (the
      file is O_APPEND, so we are not losing any concurrency).
      
      As the result, we do not need to bother with get_file()/fput()
      on log write anymore.  Moreover, do_acct_process() only needs
      acct itself; file and pidns are picked from it.
      
      Killed instances are distinguished by having NULL ->ns.
      Refcount is protected by acct_lock; anybody taking the
      mutex needs to grab a reference first.
      
      The things will get a lot simpler in the next commits - this
      is just the minimal chunk switching to the new lifetime rules.
      Signed-off-by: default avatarAl Viro <viro@zeniv.linux.org.uk>
      b8f00e6b
    • Al Viro's avatar
      acct: serialize acct_on() · 9df7fa16
      Al Viro authored
      brute-force - on a global mutex that isn't nested into anything.
      Signed-off-by: default avatarAl Viro <viro@zeniv.linux.org.uk>
      9df7fa16
    • Al Viro's avatar
      acct() should honour the limits from the very beginning · 795a2f22
      Al Viro authored
      We need to check free space on the first write to freshly opened log.
      Signed-off-by: default avatarAl Viro <viro@zeniv.linux.org.uk>
      795a2f22
    • Al Viro's avatar
      split the slow path in acct_process() off · e25ff11f
      Al Viro authored
      Signed-off-by: default avatarAl Viro <viro@zeniv.linux.org.uk>
      e25ff11f
    • Al Viro's avatar
      cdd37e23
    • Al Viro's avatar
      acct: switch to __kernel_write() · ed44724b
      Al Viro authored
      Signed-off-by: default avatarAl Viro <viro@zeniv.linux.org.uk>
      ed44724b
    • Al Viro's avatar
      acct: encode_comp_t(0) is 0, fortunately... · ecfdb33d
      Al Viro authored
      There was an amusing bogosity in ac_rw calculation - it tried to
      do encode_comp_t(encode_comp_t(0) / 1024).  Seeing that comp_t is
      a 3-bit exponent + 13-bit mantissa... it's a good thing that 0 is
      represented by all-bits-clear.
      
      The history of that one is interesting - it was introduced in
      2.1.68pre1, when acct.c had been reworked and moved to separate
      file.  Two months later (2.1.86) somebody has noticed that the
      sucker won't compile - there was no task_struct::io_usage.
      At which point the ac_io calculation had changed from
      encode_comp_t(current->io_usage) to encode_comp_t(0) and the
      bug in the next line (absolutely real back then, had it ever
      managed to compile) become a harmless bogosity.  Looks like
      nobody has ever noticed until now.
      
      Anyway, let's bury that idiocy now that it got noticed.  17 years
      is long enough...
      Signed-off-by: default avatarAl Viro <viro@zeniv.linux.org.uk>
      ecfdb33d
  12. 23 Jul, 2014 1 commit
  13. 12 Jun, 2014 1 commit
  14. 06 Jun, 2014 2 commits
  15. 04 May, 2013 1 commit
  16. 09 Apr, 2013 1 commit
  17. 23 Feb, 2013 1 commit
  18. 27 Jan, 2013 1 commit
    • Frederic Weisbecker's avatar
      cputime: Use accessors to read task cputime stats · 6fac4829
      Frederic Weisbecker authored
      This is in preparation for the full dynticks feature. While
      remotely reading the cputime of a task running in a full
      dynticks CPU, we'll need to do some extra-computation. This
      way we can account the time it spent tickless in userspace
      since its last cputime snapshot.
      Signed-off-by: default avatarFrederic Weisbecker <fweisbec@gmail.com>
      Cc: Andrew Morton <akpm@linux-foundation.org>
      Cc: Ingo Molnar <mingo@kernel.org>
      Cc: Li Zhong <zhong@linux.vnet.ibm.com>
      Cc: Namhyung Kim <namhyung.kim@lge.com>
      Cc: Paul E. McKenney <paulmck@linux.vnet.ibm.com>
      Cc: Paul Gortmaker <paul.gortmaker@windriver.com>
      Cc: Peter Zijlstra <peterz@infradead.org>
      Cc: Steven Rostedt <rostedt@goodmis.org>
      Cc: Thomas Gleixner <tglx@linutronix.de>
      6fac4829
  19. 13 Oct, 2012 1 commit