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  1. Dec 03, 2008
    • Andreas Gruenbacher's avatar
      genksyms: allow to ignore symbol checksum changes · 5dae9a55
      Andreas Gruenbacher authored 
      

This adds an "override" keyword for use in *.symvers / *.symref files.
When a symbol is overridden, the symbol's old definition will be used for
computing checksums instead of the new one, preserving the previous
checksum.  (Genksyms will still warn about the change.)

This is meant to allow distributions to hide minor actual as well as fake
ABI changes.  (For example, when extra type information becomes available
because additional headers are included, this may change checksums even
though none of the types used have actully changed.)

This approach also allows to get rid of "#ifdef __GENKSYMS__" hacks in the
code, which are currently used in some vendor kernels to work around
checksum changes.

Signed-off-by: default avatarAndreas Gruenbacher <agruen@suse.de>
Cc: Randy Dunlap <randy.dunlap@oracle.com>
Signed-off-by: default avatarAndrew Morton <akpm@linux-foundation.org>
Signed-off-by: default avatarSam Ravnborg <sam@ravnborg.org>
      5dae9a55
    • Andreas Gruenbacher's avatar
      genksyms: track symbol checksum changes · 64e6c1e1
      Andreas Gruenbacher authored 
      

Sometimes it is preferable to avoid changes of exported symbol checksums
(to avoid breaking externally provided modules).  When a checksum change
occurs, it can be hard to figure out what caused this change: underlying
types may have changed, or additional type information may simply have
become available at the point where a symbol is exported.

Add a new --reference option to genksyms which allows it to report why
checksums change, based on the type information dumps it creates with the
--dump-types flag.  Genksyms will read in such a dump from a previous run,
and report which symbols have changed (and why).

The behavior can be controlled for an entire build as follows: If
KBUILD_SYMTYPES is set, genksyms uses --dump-types to produce *.symtypes
dump files.  If any *.symref files exist, those will be used as the
reference to check against.  If KBUILD_PRESERVE is set, checksum changes
will fail the build.

Signed-off-by: default avatarAndreas Gruenbacher <agruen@suse.de>
Cc: Randy Dunlap <randy.dunlap@oracle.com>
Signed-off-by: default avatarAndrew Morton <akpm@linux-foundation.org>
Signed-off-by: default avatarSam Ravnborg <sam@ravnborg.org>
      64e6c1e1
  3. Jul 31, 2008
    • Andreas Gruenbacher's avatar
      kbuild: genksyms: Include extern information in dumps · 3b40d381
      Andreas Gruenbacher authored 
      

The extern flag currently is not included in type dump files
(genksyms --dump-types). Include that flag there for completeness.

Signed-off-by: default avatarAndreas Gruenbacher <agruen@suse.de>
Signed-off-by: default avatarSam Ravnborg <sam@ravnborg.org>
      3b40d381
    • Andreas Gruenbacher's avatar
      kbuild: genksyms parser: fix the __attribute__ rule · 94aa3d71
      Andreas Gruenbacher authored 
      

We are having two kinds of problems with genksyms today: fake checksum
changes without actual ABI changes, and changes which we would rather like
to ignore (such as an additional field at the end of a structure that
modules are not supposed to touch, for example).

I have thought about ways to improve genksyms and compute checksums
differently to avoid those problems, but in the end I don't see a
fundamentally better way.  So here are some genksyms patches for at least
making the checksums more easily manageable, if we cannot fully fix them.

In addition to the bugfixes (the first two patches), this allows genksyms
to track checksum changes and report why a checksum changed (third patch),
and to selectively ignore changes (fourth patch).

This patch:

Gcc __attribute__ definitions may occur repeatedly, e.g.,

	static int foo __attribute__((__used__))
		       __attribute__((aligned (16)));

The genksyms parser does not understand this, and generates a syntax error.
Fix this case.

Signed-off-by: default avatarAndreas Gruenbacher <agruen@suse.de>
Cc: Randy Dunlap <randy.dunlap@oracle.com>
Signed-off-by: default avatarAndrew Morton <akpm@linux-foundation.org>
Signed-off-by: default avatarSam Ravnborg <sam@ravnborg.org>
      94aa3d71
  5. Jul 30, 2008
  7. Jul 24, 2008
  9. Jan 28, 2008
  11. Oct 12, 2007
    • Sam Ravnborg's avatar
      kbuild: apply genksyms changes · 70f75246
      Sam Ravnborg authored 
      

This patch updates the _shipped files for genksyms.
See previous patch for actual functional changes.

Signed-off-by: default avatarSam Ravnborg <sam@ravnborg.org>
      70f75246
    • Sam Ravnborg's avatar
      kbuild: __extension__ support in genksyms (fix unknown CRC warning) · 3550a516
      Sam Ravnborg authored 
      

Recently the __extension__ keyword has been introduced in the kernel.
Teach genksyms about this keyword so it can generate correct CRC for
exported symbols that uses a symbol marked __extension__.
For now only the typedef variant:

	__extension__ typedef ...

is supported.
Later we may add more variants as needed.

This patch contains the actual source file changes. The
following patch will hold modifications to the generated
files (*_shipped) and only after the second patch the fix
has effect.

Signed-off-by: default avatarSam Ravnborg <sam@ravnborg.org>
      3550a516
    • Sam Ravnborg's avatar
      kbuild: fix genksyms Makefile · a3a6261a
      Sam Ravnborg authored 
      

When enabling GENERATE_PARSER the genksyms Makefile
failed to create _shipped version of generated files.

Modifying keywords.gperf failed to cause a rebuild
of genksyms.
Fixed by specifying keywowrds .c as explicit prerequisite
of the lexer.

Signed-off-by: default avatarSam Ravnborg <sam@ravnborg.org>
      a3a6261a
  13. May 07, 2007
  15. Jun 24, 2006
    • Sam Ravnborg's avatar
      kbuild: replace abort() with exit(1) · 6803dc0e
      Sam Ravnborg authored 
      

We have had no use of the coredump file for a long time.
So just exit(1) and avoid coredumping.

Signed-off-by: default avatarSam Ravnborg <sam@ravnborg.org>
      6803dc0e
    • Andreas Gruenbacher's avatar
      kbuild: support for %.symtypes files · 15fde675
      Andreas Gruenbacher authored 
      

Here is a patch that adds a new -T option to genksyms for generating dumps of
the type definition that makes up the symbol version hashes. This allows to
trace modversion changes back to what caused them. The dump format is the
name of the type defined, followed by its definition (which is almost C):

  s#list_head struct list_head { s#list_head * next , * prev ; }

The s#, u#, e#, and t# prefixes stand for struct, union, enum, and typedef.
The exported symbols do not define types, and thus do not have an x# prefix:

  nfs4_acl_get_whotype int nfs4_acl_get_whotype ( char * , t#u32 )

The symbol type defintion of a single file can be generated with:

  make fs/jbd/journal.symtypes

If KBUILD_SYMTYPES is defined, all the *.symtypes of all object files that
export symbols are generated.

The single *.symtypes files can be combined into a single file after a kernel
build with a script like the following:

for f in $(find -name '*.symtypes' | sort); do
    f=${f#./}
    echo "/* ${f%.symtypes}.o */"
    cat $f
    echo
done \
| sed -e '\:UNKNOWN:d' \
      -e 's:[,;] }:}:g' \
      -e 's:\([[({]\) :\1:g' \
      -e 's: \([])},;]\):\1:g' \
      -e 's: $::' \
      $f \
| awk '
/^.#/   { if (defined[$1] == $0) {
            print $1
            next
          }
          defined[$1] = $0
        }
        { print }
'

When the kernel ABI changes, diffing individual *.symtype files, or the
combined files, against each other will show which symbol changes caused the
ABI changes. This can save a tremendous amount of time.

Dump the types that make up modversions

Signed-off-by: default avatarAndreas Gruenbacher <agruen@suse.de>
Signed-off-by: default avatarSam Ravnborg <sam@ravnborg.org>
      15fde675
  17. Mar 20, 2006
  19. Mar 12, 2006
  21. Mar 08, 2006
  23. Jan 01, 2006
  25. Dec 26, 2005
    • Sam Ravnborg's avatar
      kbuild: Create _shipped files for genksyms · c40f5640
      Sam Ravnborg authored 
      

Generate _shipped files so the genksyms change in previous commit is enabled.
The files are generated with latest versions of the tools:

bison (GNU Bison) 2.0
flex version 2.5.4
GNU gperf 3.0.1

Signed-off-by: default avatarSam Ravnborg <sam@ravnborg.org>
      c40f5640
    • Robin Holt's avatar
      kbuild: Fix genksyms handling of DEFINE_PER_CPU(struct foo_s *, bar); · a89a0a23
      Robin Holt authored 
      

This is a one-line change to parse.y.
To take advantage of this the scripts/genksyms/*_shipped files needs to
be rebuild - this is the next patch.

When a .c file contains:
DEFINE_PER_CPU(struct foo_s *, bar);

the .cpp output looks like:
__attribute__((__section__(".data.percpu"))) __typeof__(struct foo_s *) per_cpu__bar;

With the existing parse.y, the value inside the paranthesis of
__typeof__() does not evaluate as a type_specifier and therefore
per_cpu__bar does not get assigned a type for genksyms which results in
the EXPORT_PER_CPU_SYMBOL() not generating a CRC value.

I have compared the Modules.symvers with and without this
patch and for ia64's defconfig, the only change is:
Before 0x00000000    per_cpu____sn_nodepda   vmlinux
After  0x9d3f3faa    per_cpu____sn_nodepda   vmlinux

per_cpu____sn_nodepda was the original source of my problems.

Signed-off-by: default avatarRobin Holt <holt@sgi.com>
Signed-off-by: default avatarSam Ravnborg <sam@ravnborg.org>
      a89a0a23
  27. Apr 16, 2005
    • Linus Torvalds's avatar
      Linux-2.6.12-rc2 · 1da177e4
      Linus Torvalds authored 
      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!
      View commits for tag v2.6.12-rc2 v2.6.12-rc2
      1da177e4