1. 12 Jun, 2018 1 commit
    • Kees Cook's avatar
      treewide: Use array_size() in vmalloc() · 42bc47b3
      Kees Cook authored
      The vmalloc() function has no 2-factor argument form, so multiplication
      factors need to be wrapped in array_size(). This patch replaces cases of:
      
              vmalloc(a * b)
      
      with:
              vmalloc(array_size(a, b))
      
      as well as handling cases of:
      
              vmalloc(a * b * c)
      
      with:
      
              vmalloc(array3_size(a, b, c))
      
      This does, however, attempt to ignore constant size factors like:
      
              vmalloc(4 * 1024)
      
      though any constants defined via macros get caught up in the conversion.
      
      Any factors with a sizeof() of "unsigned char", "char", and "u8" were
      dropped, since they're redundant.
      
      The Coccinelle script used for this was:
      
      // Fix redundant parens around sizeof().
      @@
      type TYPE;
      expression THING, E;
      @@
      
      (
        vmalloc(
      -	(sizeof(TYPE)) * E
      +	sizeof(TYPE) * E
        , ...)
      |
        vmalloc(
      -	(sizeof(THING)) * E
      +	sizeof(THING) * E
        , ...)
      )
      
      // Drop single-byte sizes and redundant parens.
      @@
      expression COUNT;
      typedef u8;
      typedef __u8;
      @@
      
      (
        vmalloc(
      -	sizeof(u8) * (COUNT)
      +	COUNT
        , ...)
      |
        vmalloc(
      -	sizeof(__u8) * (COUNT)
      +	COUNT
        , ...)
      |
        vmalloc(
      -	sizeof(char) * (COUNT)
      +	COUNT
        , ...)
      |
        vmalloc(
      -	sizeof(unsigned char) * (COUNT)
      +	COUNT
        , ...)
      |
        vmalloc(
      -	sizeof(u8) * COUNT
      +	COUNT
        , ...)
      |
        vmalloc(
      -	sizeof(__u8) * COUNT
      +	COUNT
        , ...)
      |
        vmalloc(
      -	sizeof(char) * COUNT
      +	COUNT
        , ...)
      |
        vmalloc(
      -	sizeof(unsigned char) * COUNT
      +	COUNT
        , ...)
      )
      
      // 2-factor product with sizeof(type/expression) and identifier or constant.
      @@
      type TYPE;
      expression THING;
      identifier COUNT_ID;
      constant COUNT_CONST;
      @@
      
      (
        vmalloc(
      -	sizeof(TYPE) * (COUNT_ID)
      +	array_size(COUNT_ID, sizeof(TYPE))
        , ...)
      |
        vmalloc(
      -	sizeof(TYPE) * COUNT_ID
      +	array_size(COUNT_ID, sizeof(TYPE))
        , ...)
      |
        vmalloc(
      -	sizeof(TYPE) * (COUNT_CONST)
      +	array_size(COUNT_CONST, sizeof(TYPE))
        , ...)
      |
        vmalloc(
      -	sizeof(TYPE) * COUNT_CONST
      +	array_size(COUNT_CONST, sizeof(TYPE))
        , ...)
      |
        vmalloc(
      -	sizeof(THING) * (COUNT_ID)
      +	array_size(COUNT_ID, sizeof(THING))
        , ...)
      |
        vmalloc(
      -	sizeof(THING) * COUNT_ID
      +	array_size(COUNT_ID, sizeof(THING))
        , ...)
      |
        vmalloc(
      -	sizeof(THING) * (COUNT_CONST)
      +	array_size(COUNT_CONST, sizeof(THING))
        , ...)
      |
        vmalloc(
      -	sizeof(THING) * COUNT_CONST
      +	array_size(COUNT_CONST, sizeof(THING))
        , ...)
      )
      
      // 2-factor product, only identifiers.
      @@
      identifier SIZE, COUNT;
      @@
      
        vmalloc(
      -	SIZE * COUNT
      +	array_size(COUNT, SIZE)
        , ...)
      
      // 3-factor product with 1 sizeof(type) or sizeof(expression), with
      // redundant parens removed.
      @@
      expression THING;
      identifier STRIDE, COUNT;
      type TYPE;
      @@
      
      (
        vmalloc(
      -	sizeof(TYPE) * (COUNT) * (STRIDE)
      +	array3_size(COUNT, STRIDE, sizeof(TYPE))
        , ...)
      |
        vmalloc(
      -	sizeof(TYPE) * (COUNT) * STRIDE
      +	array3_size(COUNT, STRIDE, sizeof(TYPE))
        , ...)
      |
        vmalloc(
      -	sizeof(TYPE) * COUNT * (STRIDE)
      +	array3_size(COUNT, STRIDE, sizeof(TYPE))
        , ...)
      |
        vmalloc(
      -	sizeof(TYPE) * COUNT * STRIDE
      +	array3_size(COUNT, STRIDE, sizeof(TYPE))
        , ...)
      |
        vmalloc(
      -	sizeof(THING) * (COUNT) * (STRIDE)
      +	array3_size(COUNT, STRIDE, sizeof(THING))
        , ...)
      |
        vmalloc(
      -	sizeof(THING) * (COUNT) * STRIDE
      +	array3_size(COUNT, STRIDE, sizeof(THING))
        , ...)
      |
        vmalloc(
      -	sizeof(THING) * COUNT * (STRIDE)
      +	array3_size(COUNT, STRIDE, sizeof(THING))
        , ...)
      |
        vmalloc(
      -	sizeof(THING) * COUNT * STRIDE
      +	array3_size(COUNT, STRIDE, sizeof(THING))
        , ...)
      )
      
      // 3-factor product with 2 sizeof(variable), with redundant parens removed.
      @@
      expression THING1, THING2;
      identifier COUNT;
      type TYPE1, TYPE2;
      @@
      
      (
        vmalloc(
      -	sizeof(TYPE1) * sizeof(TYPE2) * COUNT
      +	array3_size(COUNT, sizeof(TYPE1), sizeof(TYPE2))
        , ...)
      |
        vmalloc(
      -	sizeof(TYPE1) * sizeof(THING2) * (COUNT)
      +	array3_size(COUNT, sizeof(TYPE1), sizeof(TYPE2))
        , ...)
      |
        vmalloc(
      -	sizeof(THING1) * sizeof(THING2) * COUNT
      +	array3_size(COUNT, sizeof(THING1), sizeof(THING2))
        , ...)
      |
        vmalloc(
      -	sizeof(THING1) * sizeof(THING2) * (COUNT)
      +	array3_size(COUNT, sizeof(THING1), sizeof(THING2))
        , ...)
      |
        vmalloc(
      -	sizeof(TYPE1) * sizeof(THING2) * COUNT
      +	array3_size(COUNT, sizeof(TYPE1), sizeof(THING2))
        , ...)
      |
        vmalloc(
      -	sizeof(TYPE1) * sizeof(THING2) * (COUNT)
      +	array3_size(COUNT, sizeof(TYPE1), sizeof(THING2))
        , ...)
      )
      
      // 3-factor product, only identifiers, with redundant parens removed.
      @@
      identifier STRIDE, SIZE, COUNT;
      @@
      
      (
        vmalloc(
      -	(COUNT) * STRIDE * SIZE
      +	array3_size(COUNT, STRIDE, SIZE)
        , ...)
      |
        vmalloc(
      -	COUNT * (STRIDE) * SIZE
      +	array3_size(COUNT, STRIDE, SIZE)
        , ...)
      |
        vmalloc(
      -	COUNT * STRIDE * (SIZE)
      +	array3_size(COUNT, STRIDE, SIZE)
        , ...)
      |
        vmalloc(
      -	(COUNT) * (STRIDE) * SIZE
      +	array3_size(COUNT, STRIDE, SIZE)
        , ...)
      |
        vmalloc(
      -	COUNT * (STRIDE) * (SIZE)
      +	array3_size(COUNT, STRIDE, SIZE)
        , ...)
      |
        vmalloc(
      -	(COUNT) * STRIDE * (SIZE)
      +	array3_size(COUNT, STRIDE, SIZE)
        , ...)
      |
        vmalloc(
      -	(COUNT) * (STRIDE) * (SIZE)
      +	array3_size(COUNT, STRIDE, SIZE)
        , ...)
      |
        vmalloc(
      -	COUNT * STRIDE * SIZE
      +	array3_size(COUNT, STRIDE, SIZE)
        , ...)
      )
      
      // Any remaining multi-factor products, first at least 3-factor products
      // when they're not all constants...
      @@
      expression E1, E2, E3;
      constant C1, C2, C3;
      @@
      
      (
        vmalloc(C1 * C2 * C3, ...)
      |
        vmalloc(
      -	E1 * E2 * E3
      +	array3_size(E1, E2, E3)
        , ...)
      )
      
      // And then all remaining 2 factors products when they're not all constants.
      @@
      expression E1, E2;
      constant C1, C2;
      @@
      
      (
        vmalloc(C1 * C2, ...)
      |
        vmalloc(
      -	E1 * E2
      +	array_size(E1, E2)
        , ...)
      )
      Signed-off-by: default avatarKees Cook <keescook@chromium.org>
      42bc47b3
  2. 29 Mar, 2018 1 commit
  3. 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
  4. 02 Mar, 2017 4 commits
  5. 24 Dec, 2016 1 commit
  6. 06 Dec, 2016 1 commit
  7. 01 Dec, 2016 1 commit
  8. 28 Sep, 2016 1 commit
  9. 19 Sep, 2016 1 commit
  10. 04 Apr, 2016 1 commit
    • Kirill A. Shutemov's avatar
      mm, fs: get rid of PAGE_CACHE_* and page_cache_{get,release} macros · 09cbfeaf
      Kirill A. Shutemov authored
      PAGE_CACHE_{SIZE,SHIFT,MASK,ALIGN} macros were introduced *long* time
      ago with promise that one day it will be possible to implement page
      cache with bigger chunks than PAGE_SIZE.
      
      This promise never materialized.  And unlikely will.
      
      We have many places where PAGE_CACHE_SIZE assumed to be equal to
      PAGE_SIZE.  And it's constant source of confusion on whether
      PAGE_CACHE_* or PAGE_* constant should be used in a particular case,
      especially on the border between fs and mm.
      
      Global switching to PAGE_CACHE_SIZE != PAGE_SIZE would cause to much
      breakage to be doable.
      
      Let's stop pretending that pages in page cache are special.  They are
      not.
      
      The changes are pretty straight-forward:
      
       - <foo> << (PAGE_CACHE_SHIFT - PAGE_SHIFT) -> <foo>;
      
       - <foo> >> (PAGE_CACHE_SHIFT - PAGE_SHIFT) -> <foo>;
      
       - PAGE_CACHE_{SIZE,SHIFT,MASK,ALIGN} -> PAGE_{SIZE,SHIFT,MASK,ALIGN};
      
       - page_cache_get() -> get_page();
      
       - page_cache_release() -> put_page();
      
      This patch contains automated changes generated with coccinelle using
      script below.  For some reason, coccinelle doesn't patch header files.
      I've called spatch for them manually.
      
      The only adjustment after coccinelle is revert of changes to
      PAGE_CAHCE_ALIGN definition: we are going to drop it later.
      
      There are few places in the code where coccinelle didn't reach.  I'll
      fix them manually in a separate patch.  Comments and documentation also
      will be addressed with the separate patch.
      
      virtual patch
      
      @@
      expression E;
      @@
      - E << (PAGE_CACHE_SHIFT - PAGE_SHIFT)
      + E
      
      @@
      expression E;
      @@
      - E >> (PAGE_CACHE_SHIFT - PAGE_SHIFT)
      + E
      
      @@
      @@
      - PAGE_CACHE_SHIFT
      + PAGE_SHIFT
      
      @@
      @@
      - PAGE_CACHE_SIZE
      + PAGE_SIZE
      
      @@
      @@
      - PAGE_CACHE_MASK
      + PAGE_MASK
      
      @@
      expression E;
      @@
      - PAGE_CACHE_ALIGN(E)
      + PAGE_ALIGN(E)
      
      @@
      expression E;
      @@
      - page_cache_get(E)
      + get_page(E)
      
      @@
      expression E;
      @@
      - page_cache_release(E)
      + put_page(E)
      Signed-off-by: default avatarKirill A. Shutemov <kirill.shutemov@linux.intel.com>
      Acked-by: default avatarMichal Hocko <mhocko@suse.com>
      Signed-off-by: default avatarLinus Torvalds <torvalds@linux-foundation.org>
      09cbfeaf
  11. 22 Jan, 2016 1 commit
    • Al Viro's avatar
      wrappers for ->i_mutex access · 5955102c
      Al Viro authored
      parallel to mutex_{lock,unlock,trylock,is_locked,lock_nested},
      inode_foo(inode) being mutex_foo(&inode->i_mutex).
      
      Please, use those for access to ->i_mutex; over the coming cycle
      ->i_mutex will become rwsem, with ->lookup() done with it held
      only shared.
      Signed-off-by: default avatarAl Viro <viro@zeniv.linux.org.uk>
      5955102c
  12. 17 Apr, 2015 1 commit
    • Davidlohr Bueso's avatar
      oprofile: reduce mmap_sem hold for mm->exe_file · 11163348
      Davidlohr Bueso authored
      sync_buffer() needs the mmap_sem for two distinct operations, both only
      occurring upon user context switch handling:
      
       1) Dealing with the exe_file.
      
       2) Adding the dcookie data as we need to lookup the vma that
         backs it. This is done via add_sample() and add_data().
      
      This patch isolates 1), for it will no longer need the mmap_sem for
      serialization.  However, for now, make of the more standard
      get_mm_exe_file(), requiring only holding the mmap_sem to read the value,
      and relying on reference counting to make sure that the exe file won't
      dissappear underneath us while doing the get dcookie.
      
      As a consequence, for 2) we move the mmap_sem locking into where we really
      need it, in lookup_dcookie().  The benefits are twofold: reduce mmap_sem
      hold times, and cleaner code.
      
      [akpm@linux-foundation.org: export get_mm_exe_file for arch/x86/oprofile/oprofile.ko]
      Signed-off-by: default avatarDavidlohr Bueso <dbueso@suse.de>
      Cc: Robert Richter <rric@kernel.org>
      Signed-off-by: default avatarAndrew Morton <akpm@linux-foundation.org>
      Signed-off-by: default avatarLinus Torvalds <torvalds@linux-foundation.org>
      11163348
  13. 15 Apr, 2015 1 commit
  14. 26 Aug, 2014 1 commit
  15. 20 Mar, 2014 1 commit
    • Srivatsa S. Bhat's avatar
      oprofile, nmi-timer: Fix CPU hotplug callback registration · 180d8646
      Srivatsa S. Bhat authored
      Subsystems that want to register CPU hotplug callbacks, as well as perform
      initialization for the CPUs that are already online, often do it as shown
      below:
      
      	get_online_cpus();
      
      	for_each_online_cpu(cpu)
      		init_cpu(cpu);
      
      	register_cpu_notifier(&foobar_cpu_notifier);
      
      	put_online_cpus();
      
      This is wrong, since it is prone to ABBA deadlocks involving the
      cpu_add_remove_lock and the cpu_hotplug.lock (when running concurrently
      with CPU hotplug operations).
      
      Instead, the correct and race-free way of performing the callback
      registration is:
      
      	cpu_notifier_register_begin();
      
      	for_each_online_cpu(cpu)
      		init_cpu(cpu);
      
      	/* Note the use of the double underscored version of the API */
      	__register_cpu_notifier(&foobar_cpu_notifier);
      
      	cpu_notifier_register_done();
      
      Fix the nmi-timer code in oprofile by using this latter form of callback
      registration.
      
      Cc: Robert Richter <rric@kernel.org>
      Cc: Ingo Molnar <mingo@kernel.org>
      Signed-off-by: default avatarSrivatsa S. Bhat <srivatsa.bhat@linux.vnet.ibm.com>
      Signed-off-by: default avatarRafael J. Wysocki <rafael.j.wysocki@intel.com>
      180d8646
  16. 04 Sep, 2013 6 commits
  17. 14 Jul, 2013 1 commit
  18. 04 Mar, 2013 1 commit
    • Eric W. Biederman's avatar
      fs: Limit sys_mount to only request filesystem modules. · 7f78e035
      Eric W. Biederman authored
      Modify the request_module to prefix the file system type with "fs-"
      and add aliases to all of the filesystems that can be built as modules
      to match.
      
      A common practice is to build all of the kernel code and leave code
      that is not commonly needed as modules, with the result that many
      users are exposed to any bug anywhere in the kernel.
      
      Looking for filesystems with a fs- prefix limits the pool of possible
      modules that can be loaded by mount to just filesystems trivially
      making things safer with no real cost.
      
      Using aliases means user space can control the policy of which
      filesystem modules are auto-loaded by editing /etc/modprobe.d/*.conf
      with blacklist and alias directives.  Allowing simple, safe,
      well understood work-arounds to known problematic software.
      
      This also addresses a rare but unfortunate problem where the filesystem
      name is not the same as it's module name and module auto-loading
      would not work.  While writing this patch I saw a handful of such
      cases.  The most significant being autofs that lives in the module
      autofs4.
      
      This is relevant to user namespaces because we can reach the request
      module in get_fs_type() without having any special permissions, and
      people get uncomfortable when a user specified string (in this case
      the filesystem type) goes all of the way to request_module.
      
      After having looked at this issue I don't think there is any
      particular reason to perform any filtering or permission checks beyond
      making it clear in the module request that we want a filesystem
      module.  The common pattern in the kernel is to call request_module()
      without regards to the users permissions.  In general all a filesystem
      module does once loaded is call register_filesystem() and go to sleep.
      Which means there is not much attack surface exposed by loading a
      filesytem module unless the filesystem is mounted.  In a user
      namespace filesystems are not mounted unless .fs_flags = FS_USERNS_MOUNT,
      which most filesystems do not set today.
      Acked-by: default avatarSerge Hallyn <serge.hallyn@canonical.com>
      Acked-by: default avatarKees Cook <keescook@chromium.org>
      Reported-by: default avatarKees Cook <keescook@google.com>
      Signed-off-by: default avatar"Eric W. Biederman" <ebiederm@xmission.com>
      7f78e035
  19. 23 Feb, 2013 1 commit
  20. 09 Oct, 2012 1 commit
  21. 27 Aug, 2012 1 commit
    • Robert Richter's avatar
      oprofile: Remove 'WQ on CPUx, prefer CPUy' warning · 61bccf19
      Robert Richter authored
      Under certain workloads we see the following warnings:
      
       WQ on CPU0, prefer CPU1
       WQ on CPU0, prefer CPU2
       WQ on CPU0, prefer CPU3
      
      It warns the user that the wq to access a per-cpu buffers runs not on
      the same cpu. This happens if the wq is rescheduled on a different cpu
      than where the buffer is located. This was probably implemented to
      detect performance issues. Not sure if there actually is one as the
      buffers are copied to a single buffer anyway which should be the
      actual bottleneck.
      
      We wont change WQ implementation. Since a user can do nothing the
      warning is pointless. Removing it.
      
      Cc: Andi Kleen <andi@firstfloor.org>
      Signed-off-by: default avatarRobert Richter <robert.richter@amd.com>
      61bccf19
  22. 22 Jun, 2012 1 commit
  23. 21 Jun, 2012 1 commit
  24. 05 Apr, 2012 1 commit
    • Stephen Boyd's avatar
      simple_open: automatically convert to simple_open() · 234e3405
      Stephen Boyd authored
      Many users of debugfs copy the implementation of default_open() when
      they want to support a custom read/write function op.  This leads to a
      proliferation of the default_open() implementation across the entire
      tree.
      
      Now that the common implementation has been consolidated into libfs we
      can replace all the users of this function with simple_open().
      
      This replacement was done with the following semantic patch:
      
      <smpl>
      @ open @
      identifier open_f != simple_open;
      identifier i, f;
      @@
      -int open_f(struct inode *i, struct file *f)
      -{
      (
      -if (i->i_private)
      -f->private_data = i->i_private;
      |
      -f->private_data = i->i_private;
      )
      -return 0;
      -}
      
      @ has_open depends on open @
      identifier fops;
      identifier open.open_f;
      @@
      struct file_operations fops = {
      ...
      -.open = open_f,
      +.open = simple_open,
      ...
      };
      </smpl>
      
      [akpm@linux-foundation.org: checkpatch fixes]
      Signed-off-by: default avatarStephen Boyd <sboyd@codeaurora.org>
      Cc: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
      Cc: Al Viro <viro@zeniv.linux.org.uk>
      Cc: Julia Lawall <Julia.Lawall@lip6.fr>
      Acked-by: default avatarIngo Molnar <mingo@elte.hu>
      Signed-off-by: default avatarAndrew Morton <akpm@linux-foundation.org>
      Signed-off-by: default avatarLinus Torvalds <torvalds@linux-foundation.org>
      234e3405
  25. 21 Mar, 2012 2 commits
  26. 19 Dec, 2011 1 commit
  27. 07 Dec, 2011 1 commit
  28. 04 Nov, 2011 3 commits
    • Robert Richter's avatar
      oprofile, x86: Reimplement nmi timer mode using perf event · dcfce4a0
      Robert Richter authored
      The legacy x86 nmi watchdog code was removed with the implementation
      of the perf based nmi watchdog. This broke Oprofile's nmi timer
      mode. To run nmi timer mode we relied on a continuous ticking nmi
      source which the nmi watchdog provided. The nmi tick was no longer
      available and current watchdog can not be used anymore since it runs
      with very long periods in the range of seconds. This patch
      reimplements the nmi timer mode using a perf counter nmi source.
      
      V2:
      * removing pr_info()
      * fix undefined reference to `__udivdi3' for 32 bit build
      * fix section mismatch of .cpuinit.data:nmi_timer_cpu_nb
      * removed nmi timer setup in arch/x86
      * implemented function stubs for op_nmi_init/exit()
      * made code more readable in oprofile_init()
      
      V3:
      * fix architectural initialization in oprofile_init()
      * fix CONFIG_OPROFILE_NMI_TIMER dependencies
      Acked-by: default avatarPeter Zijlstra <a.p.zijlstra@chello.nl>
      Signed-off-by: default avatarRobert Richter <robert.richter@amd.com>
      dcfce4a0
    • Robert Richter's avatar
      oprofile: Remove exit function for timer mode · 75c43a20
      Robert Richter authored
      Remove exit functions by moving init/exit code to oprofile's setup/
      shutdown functions. Doing so the oprofile module exit code will be
      easier and less error-prone.
      Signed-off-by: default avatarRobert Richter <robert.richter@amd.com>
      75c43a20
    • Robert Richter's avatar
      oprofile: Fix crash when unloading module (hr timer mode) · 87121ca5
      Robert Richter authored
      Oprofile may crash in a KVM guest while unlaoding modules. This
      happens if oprofile_arch_init() fails and oprofile switches to the hr
      timer mode as a fallback. In this case oprofile_arch_exit() is called,
      but it never was initialized properly which causes the crash. This
      patch fixes this.
      
      oprofile: using timer interrupt.
      BUG: unable to handle kernel NULL pointer dereference at 0000000000000008
      IP: [<ffffffff8123c226>] unregister_syscore_ops+0x41/0x58
      PGD 41da3f067 PUD 41d80e067 PMD 0
      Oops: 0002 [#1] PREEMPT SMP
      CPU 5
      Modules linked in: oprofile(-)
      
      Pid: 2382, comm: modprobe Not tainted 3.1.0-rc7-00018-g709a39d #18 Advanced Micro Device Anaheim/Anaheim
      RIP: 0010:[<ffffffff8123c226>]  [<ffffffff8123c226>] unregister_syscore_ops+0x41/0x58
      RSP: 0018:ffff88041de1de98  EFLAGS: 00010296
      RAX: 0000000000000000 RBX: ffffffffa00060e0 RCX: dead000000200200
      RDX: 0000000000000000 RSI: dead000000100100 RDI: ffffffff8178c620
      RBP: ffff88041de1dea8 R08: 0000000000000001 R09: 0000000000000082
      R10: 0000000000000000 R11: ffff88041de1dde8 R12: 0000000000000080
      R13: fffffffffffffff5 R14: 0000000000000001 R15: 0000000000610210
      FS:  00007f9ae5bef700(0000) GS:ffff88042fd40000(0000) knlGS:0000000000000000
      CS:  0010 DS: 0000 ES: 0000 CR0: 000000008005003b
      CR2: 0000000000000008 CR3: 000000041ca44000 CR4: 00000000000006e0
      DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000
      DR3: 0000000000000000 DR6: 00000000ffff0ff0 DR7: 0000000000000400
      Process modprobe (pid: 2382, threadinfo ffff88041de1c000, task ffff88042db6d040)
      Stack:
       ffff88041de1deb8 ffffffffa0006770 ffff88041de1deb8 ffffffffa000251e
       ffff88041de1dec8 ffffffffa00022c2 ffff88041de1ded8 ffffffffa0004993
       ffff88041de1df78 ffffffff81073115 656c69666f72706f 0000000000610200
      Call Trace:
       [<ffffffffa000251e>] op_nmi_exit+0x15/0x17 [oprofile]
       [<ffffffffa00022c2>] oprofile_arch_exit+0xe/0x10 [oprofile]
       [<ffffffffa0004993>] oprofile_exit+0x13/0x15 [oprofile]
       [<ffffffff81073115>] sys_delete_module+0x1c3/0x22f
       [<ffffffff811bf09e>] ? trace_hardirqs_on_thunk+0x3a/0x3f
       [<ffffffff8148070b>] system_call_fastpath+0x16/0x1b
      Code: 20 c6 78 81 e8 c5 cc 23 00 48 8b 13 48 8b 43 08 48 be 00 01 10 00 00 00 ad de 48 b9 00 02 20 00 00 00 ad de 48 c7 c7 20 c6 78 81
       89 42 08 48 89 10 48 89 33 48 89 4b 08 e8 a6 c0 23 00 5a 5b
      RIP  [<ffffffff8123c226>] unregister_syscore_ops+0x41/0x58
       RSP <ffff88041de1de98>
      CR2: 0000000000000008
      ---[ end trace 06d4e95b6aa3b437 ]---
      
      CC: stable@kernel.org # 2.6.37+
      Signed-off-by: default avatarRobert Richter <robert.richter@amd.com>
      87121ca5
  29. 13 Sep, 2011 1 commit