1. 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
  2. 09 Jun, 2017 1 commit
    • Arnd Bergmann's avatar
      kbuild: speed up checksyscalls.sh · d21832e2
      Arnd Bergmann authored
      checksyscalls.sh is run at every "make" run while building the kernel,
      even if no files have changed. I looked at where we spend time in
      a trivial empty rebuild and found checksyscalls.sh to be a source
      of noticeable overhead, as it spawns a lot of child processes just
      to call 'cat' copying from stdin to stdout, once for each of the
      over 400 x86 syscalls.
      
      Using a shell-builtin (echo) instead of the external command gives
      us a 13x speedup:
      
          Before		   After
      real	0m1.018s       real	0m0.077s
      user	0m0.068s       user	0m0.048s
      sys	0m0.156s       sys	0m0.024s
      
      The time it took to rebuild a single file on my machine dropped
      from 5.5 seconds to 4.5 seconds.
      Signed-off-by: default avatarArnd Bergmann <arnd@arndb.de>
      Signed-off-by: Masahiro Yamada's avatarMasahiro Yamada <yamada.masahiro@socionext.com>
      d21832e2
  3. 24 Mar, 2017 1 commit
  4. 04 Jun, 2015 1 commit
    • Ingo Molnar's avatar
      x86/asm/entry: Move the arch/x86/syscalls/ definitions to arch/x86/entry/syscalls/ · 1f57d5d8
      Ingo Molnar authored
      The build time generated syscall definitions are entry code related, move
      them into the arch/x86/entry/ directory.
      
      Cc: Borislav Petkov <bp@alien8.de>
      Cc: H. Peter Anvin <hpa@zytor.com>
      Cc: Linus Torvalds <torvalds@linux-foundation.org>
      Cc: Thomas Gleixner <tglx@linutronix.de>
      Cc: Andy Lutomirski <luto@amacapital.net>
      Cc: Denys Vlasenko <dvlasenk@redhat.com>
      Cc: Brian Gerst <brgerst@gmail.com>
      Cc: Peter Zijlstra <peterz@infradead.org>
      Cc: linux-kernel@vger.kernel.org
      Signed-off-by: default avatarIngo Molnar <mingo@kernel.org>
      1f57d5d8
  5. 20 May, 2014 1 commit
  6. 25 Sep, 2012 1 commit
  7. 17 Nov, 2011 1 commit
  8. 20 Dec, 2010 1 commit
  9. 25 Jun, 2010 1 commit
    • Chris Metcalf's avatar
      Add wait4() back to the set of <asm-generic/unistd.h> syscalls. · b51cae21
      Chris Metcalf authored
      The initial pass at the generic ABI assumed that wait4() could be
      easily expressed using waitid().  Although it's true that wait4()
      can be built on waitid(), it's awkward enough that it makes more
      sense to continue to include wait4 in the generic syscall ABI.
      
      Since there is already a deprecated wait4 in the ABI, this change
      converts that wait4 into old_wait, and puts wait4 in the next
      available slot for new supported syscalls, after the platform-specific
      syscalls at number 260.
      Signed-off-by: default avatarChris Metcalf <cmetcalf@tilera.com>
      Acked-by: default avatarArnd Bergmann <arnd@arndb.de>
      b51cae21
  10. 11 Jun, 2009 1 commit
    • Arnd Bergmann's avatar
      asm-generic: add a generic unistd.h · e64a1617
      Arnd Bergmann authored
      A new architecture should only define a minimal set of system
      calls while still providing the full functionality. This version
      of unistd.h has gone through intensive review to make sure that
      by default it only enables syscalls that do not already have
      a more featureful replacement.
      
      It is modeled after the x86-64 version of unistd.h, which unifies
      the syscall number definition and the actual system call table
      in a single file, in order to keep them synchronized much more
      easily.
      
      This first version still keeps legacy system call definitions
      around, guarded by various #ifdefs, and with numbers larger
      than 1024. The idea behind this is to make it easier for
      new architectures to transition from a full list to the reduced
      set. In particular, the new microblaze architecture that should
      migrate to using the generic ABI headers can at least use an
      existing uClibc source tree without major rewrites during the
      conversion.
      Signed-off-by: default avatarArnd Bergmann <arnd@arndb.de>
      e64a1617
  11. 29 Oct, 2008 1 commit
  12. 23 Oct, 2008 1 commit
  13. 11 Oct, 2007 1 commit
  14. 28 Jun, 2007 1 commit
    • David Woodhouse's avatar
      Introduce fixed sys_sync_file_range2() syscall, implement on PowerPC and ARM · edd5cd4a
      David Woodhouse authored
      Not all the world is an i386.  Many architectures need 64-bit arguments to be
      aligned in suitable pairs of registers, and the original
      sys_sync_file_range(int, loff_t, loff_t, int) was therefore wasting an
      argument register for padding after the first integer.  Since we don't
      normally have more than 6 arguments for system calls, that left no room for
      the final argument on some architectures.
      
      Fix this by introducing sys_sync_file_range2(int, int, loff_t, loff_t) which
      all fits nicely.  In fact, ARM already had that, but called it
      sys_arm_sync_file_range.  Move it to fs/sync.c and rename it, then implement
      the needed compatibility routine.  And stop the missing syscall check from
      bitching about the absence of sys_sync_file_range() if we've implemented
      sys_sync_file_range2() instead.
      
      Tested on PPC32 and with 32-bit and 64-bit userspace on PPC64.
      Signed-off-by: default avatarDavid Woodhouse <dwmw2@infradead.org>
      Acked-by: default avatarRussell King <rmk+kernel@arm.linux.org.uk>
      Cc: Arnd Bergmann <arnd@arndb.de>
      Cc: Paul Mackerras <paulus@samba.org>
      Signed-off-by: default avatarAndrew Morton <akpm@linux-foundation.org>
      Signed-off-by: default avatarLinus Torvalds <torvalds@linux-foundation.org>
      edd5cd4a
  15. 02 May, 2007 1 commit
    • Sam Ravnborg's avatar
      kbuild: complain about missing system calls · c53aeca0
      Sam Ravnborg authored
      Most system calls seems to get added to i386 first. This patch
      automatically generates a warning for any new system call which is
      implemented on i386 but not the architecture currently being compiled.
      On PowerPC at the moment, for example, it results in these warnings:
      init/missing_syscalls.h:935:3: warning: #warning syscall sync_file_range not implemented
      init/missing_syscalls.h:947:3: warning: #warning syscall getcpu not implemented
      init/missing_syscalls.h:950:3: warning: #warning syscall epoll_pwait not implemented
      
      The file scripts/checksyscalls.sh list a number of legacy system calls
      that are ignored because they only makes sense on i386 systems.
      
      Other contributors to this patch are Russell King <rmk+lkml@arm.linux.org.uk>
      and Stéphane Jourdois <kwisatz@rubis.org>
      Signed-off-by: default avatarDavid Woodhouse <dwmw2@infradead.org>
      Signed-off-by: default avatarSam Ravnborg <sam@ravnborg.org>
      c53aeca0