02 Nov, 2017

1 commit

  • 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
    Reviewed-by: Philippe Ombredanne
    Reviewed-by: Thomas Gleixner
    Signed-off-by: Greg Kroah-Hartman

    Greg Kroah-Hartman
     

13 Aug, 2010

1 commit

  • Don't try and #include in lib/inflate.c from the bootloader code
    as linux/slab.h hauls in function defs that aren't available in the bootloader
    code and may also haul in conflicting functions.

    To fix this, make the inclusion of linux/slab.h contingent on NO_INFLATE_MALLOC
    as are the usages of kmalloc() and kfree().

    In MN10300, this causes the following errors:

    In file included from include/linux/string.h:21,
    from include/linux/bitmap.h:8,
    from include/linux/nodemask.h:93,
    from include/linux/mmzone.h:16,
    from include/linux/gfp.h:4,
    from include/linux/slab.h:12,
    from arch/mn10300/boot/compressed/../../../../lib/inflate.c:106,
    from arch/mn10300/boot/compressed/misc.c:170:
    /warthog/am33/linux-2.6-mn10300/arch/mn10300/include/asm/string.h:19: error: conflicting types for 'memset'
    arch/mn10300/boot/compressed/misc.c:59: error: previous definition of 'memset' was here

    Signed-off-by: David Howells
    Signed-off-by: Linus Torvalds

    David Howells
     

30 Mar, 2010

1 commit

  • …it slab.h inclusion from percpu.h

    percpu.h is included by sched.h and module.h and thus ends up being
    included when building most .c files. percpu.h includes slab.h which
    in turn includes gfp.h making everything defined by the two files
    universally available and complicating inclusion dependencies.

    percpu.h -> slab.h dependency is about to be removed. Prepare for
    this change by updating users of gfp and slab facilities include those
    headers directly instead of assuming availability. As this conversion
    needs to touch large number of source files, the following script is
    used as the basis of conversion.

    http://userweb.kernel.org/~tj/misc/slabh-sweep.py

    The script does the followings.

    * Scan files for gfp and slab usages and update includes such that
    only the necessary includes are there. ie. if only gfp is used,
    gfp.h, if slab is used, slab.h.

    * When the script inserts a new include, it looks at the include
    blocks and try to put the new include such that its order conforms
    to its surrounding. It's put in the include block which contains
    core kernel includes, in the same order that the rest are ordered -
    alphabetical, Christmas tree, rev-Xmas-tree or at the end if there
    doesn't seem to be any matching order.

    * If the script can't find a place to put a new include (mostly
    because the file doesn't have fitting include block), it prints out
    an error message indicating which .h file needs to be added to the
    file.

    The conversion was done in the following steps.

    1. The initial automatic conversion of all .c files updated slightly
    over 4000 files, deleting around 700 includes and adding ~480 gfp.h
    and ~3000 slab.h inclusions. The script emitted errors for ~400
    files.

    2. Each error was manually checked. Some didn't need the inclusion,
    some needed manual addition while adding it to implementation .h or
    embedding .c file was more appropriate for others. This step added
    inclusions to around 150 files.

    3. The script was run again and the output was compared to the edits
    from #2 to make sure no file was left behind.

    4. Several build tests were done and a couple of problems were fixed.
    e.g. lib/decompress_*.c used malloc/free() wrappers around slab
    APIs requiring slab.h to be added manually.

    5. The script was run on all .h files but without automatically
    editing them as sprinkling gfp.h and slab.h inclusions around .h
    files could easily lead to inclusion dependency hell. Most gfp.h
    inclusion directives were ignored as stuff from gfp.h was usually
    wildly available and often used in preprocessor macros. Each
    slab.h inclusion directive was examined and added manually as
    necessary.

    6. percpu.h was updated not to include slab.h.

    7. Build test were done on the following configurations and failures
    were fixed. CONFIG_GCOV_KERNEL was turned off for all tests (as my
    distributed build env didn't work with gcov compiles) and a few
    more options had to be turned off depending on archs to make things
    build (like ipr on powerpc/64 which failed due to missing writeq).

    * x86 and x86_64 UP and SMP allmodconfig and a custom test config.
    * powerpc and powerpc64 SMP allmodconfig
    * sparc and sparc64 SMP allmodconfig
    * ia64 SMP allmodconfig
    * s390 SMP allmodconfig
    * alpha SMP allmodconfig
    * um on x86_64 SMP allmodconfig

    8. percpu.h modifications were reverted so that it could be applied as
    a separate patch and serve as bisection point.

    Given the fact that I had only a couple of failures from tests on step
    6, I'm fairly confident about the coverage of this conversion patch.
    If there is a breakage, it's likely to be something in one of the arch
    headers which should be easily discoverable easily on most builds of
    the specific arch.

    Signed-off-by: Tejun Heo <tj@kernel.org>
    Guess-its-ok-by: Christoph Lameter <cl@linux-foundation.org>
    Cc: Ingo Molnar <mingo@redhat.com>
    Cc: Lee Schermerhorn <Lee.Schermerhorn@hp.com>

    Tejun Heo
     

16 Sep, 2009

1 commit


26 Jul, 2008

1 commit

  • Inflate requires some dynamic memory allocation very early in the boot
    process and this is provided with a set of four functions:
    malloc/free/gzip_mark/gzip_release.

    The old inflate code used a mark/release strategy rather than implement
    free. This new version instead keeps a count on the number of outstanding
    allocations and when it hits zero, it resets the malloc arena.

    This allows removing all the mark and release implementations and unifying
    all the malloc/free implementations.

    The architecture-dependent code must define two addresses:
    - free_mem_ptr, the address of the beginning of the area in which
    allocations should be made
    - free_mem_end_ptr, the address of the end of the area in which
    allocations should be made. If set to 0, then no check is made on
    the number of allocations, it just grows as much as needed

    The architecture-dependent code can also provide an arch_decomp_wdog()
    function call. This function will be called several times during the
    decompression process, and allow to notify the watchdog that the system is
    still running. If an architecture provides such a call, then it must
    define ARCH_HAS_DECOMP_WDOG so that the generic inflate code calls
    arch_decomp_wdog().

    Work initially done by Matt Mackall, updated to a recent version of the
    kernel and improved by me.

    [akpm@linux-foundation.org: coding-style fixes]
    Signed-off-by: Thomas Petazzoni
    Cc: Matt Mackall
    Cc: Richard Henderson
    Cc: Ivan Kokshaysky
    Cc: Mikael Starvik
    Cc: Jesper Nilsson
    Cc: Haavard Skinnemoen
    Cc: David Howells
    Cc: Ingo Molnar
    Cc: Thomas Gleixner
    Cc: Andi Kleen
    Cc: "H. Peter Anvin"
    Acked-by: Paul Mundt
    Acked-by: Yoshinori Sato
    Signed-off-by: Andrew Morton
    Signed-off-by: Linus Torvalds

    Thomas Petazzoni
     

29 Apr, 2008

1 commit


03 May, 2007

2 commits

  • inflate_dynamic() has piggy stack usage too, so heap allocate it too.
    I'm not sure it actually gets used, but it shows up large in "make
    checkstack".

    Signed-off-by: Jeremy Fitzhardinge
    Signed-off-by: Andi Kleen

    Jeremy Fitzhardinge
     
  • inflate_fixed and huft_build together use around 2.7k of stack. When
    using 4k stacks, I saw stack overflows from interrupts arriving while
    unpacking the root initrd:

    do_IRQ: stack overflow: 384
    [] show_trace_log_lvl+0x1a/0x30
    [] show_trace+0x12/0x14
    [] dump_stack+0x16/0x18
    [] do_IRQ+0x6d/0xd9
    [] xen_evtchn_do_upcall+0x6e/0xa2
    [] xen_hypervisor_callback+0x25/0x2c
    [] xen_restore_fl+0x27/0x29
    [] _spin_unlock_irqrestore+0x4a/0x50
    [] change_page_attr+0x577/0x584
    [] kernel_map_pages+0x8d/0xb4
    [] cache_alloc_refill+0x53f/0x632
    [] __kmalloc+0xc1/0x10d
    [] malloc+0x10/0x12
    [] huft_build+0x2a7/0x5fa
    [] inflate_fixed+0x91/0x136
    [] unpack_to_rootfs+0x5f2/0x8c1
    [] populate_rootfs+0x1e/0xe4

    (This was under Xen, but there's no reason it couldn't happen on bare
    hardware.)

    This patch mallocs the local variables, thereby reducing the stack
    usage to sane levels.

    Also, up the heap size for the kernel decompressor to deal with the
    extra allocation.

    Signed-off-by: Jeremy Fitzhardinge
    Signed-off-by: Andi Kleen
    Cc: Tim Yamin
    Cc: Andi Kleen
    Cc: Matt Mackall
    Cc: Ivan Kokshaysky
    Cc: Richard Henderson
    Cc: Russell King
    Cc: Ian Molton

    Jeremy Fitzhardinge
     

06 Aug, 2005

1 commit

  • These bugs have been fixed in the standard zlib for a while.

    See for example

    a) http://sources.redhat.com/ml/bug-gnu-utils/1999-06/msg00183.html
    b) http://bugs.gentoo.org/show_bug.cgi?id=94584

    Signed-off-by: Tim Yamin
    Signed-off-by: Tavis Ormandy
    Signed-off-by: Linus Torvalds

    Tim Yamin
     

17 Apr, 2005

1 commit

  • Initial git repository build. I'm not bothering with the full history,
    even though we have it. We can create a separate "historical" git
    archive of that later if we want to, and in the meantime it's about
    3.2GB when imported into git - space that would just make the early
    git days unnecessarily complicated, when we don't have a lot of good
    infrastructure for it.

    Let it rip!

    Linus Torvalds