linux-toradex.git/Makefile, branch v2.6.31-rc4

Linux 2.6.31-rc4

2009-07-23T02:32:59+00:00

Add '-fno-delete-null-pointer-checks' to gcc CFLAGS

2009-07-16T16:19:16+00:00

Turning on this flag could prevent the compiler from optimising away
some "useless" checks for null pointers.  Such bugs can sometimes become
exploitable at compile time because of the -O2 optimisation.

See http://gcc.gnu.org/onlinedocs/gcc-4.1.2/gcc/Optimize-Options.html

An example that clearly shows this 'problem' is commit 6bf67672.

 static void __devexit agnx_pci_remove(struct pci_dev *pdev)
 {
     struct ieee80211_hw *dev = pci_get_drvdata(pdev);
-    struct agnx_priv *priv = dev->priv;
+    struct agnx_priv *priv;
     AGNX_TRACE;

     if (!dev)
         return;
+    priv = dev->priv;

By reverting this patch, and compile it with and without
-fno-delete-null-pointer-checks flag, we can see that the check for dev
is compiled away.

    call    printk  #
-   testq   %r12, %r12  # dev
-   je  .L94    #,
    movq    %r12, %rdi  # dev,

Clearly the 'fix' is to stop using dev before it is tested, but building
with -fno-delete-null-pointer-checks flag at least makes it harder to
abuse.

Signed-off-by: Eugene Teo 
Acked-by: Eric Paris 
Acked-by: Wang Cong 
Signed-off-by: Linus Torvalds

Linux 2.6.31-rc3

2009-07-14T01:18:52+00:00

Don't use '-fwrapv' compiler option: it's buggy in gcc-4.1.x

2009-07-12T18:25:04+00:00

This causes kernel images that don't run init to completion with certain
broken gcc versions.

This fixes kernel bugzilla entry:
	http://bugzilla.kernel.org/show_bug.cgi?id=13012

I suspect the gcc problem is this:
	http://gcc.gnu.org/bugzilla/show_bug.cgi?id=28230

Fix the problem by using the -fno-strict-overflow flag instead, which
not only does not exist in the known-to-be-broken versions of gcc (it
was introduced later than fwrapv), but seems to be much less disturbing
to gcc too: the difference in the generated code by -fno-strict-overflow
are smaller (compared to using neither flag) than when using -fwrapv.

Reported-by: Barry K. Nathan 
Pushed-by: Frans Pop 
Cc: Andrew Morton 
Cc: stable@kernel.org
Signed-off-by: Linus Torvalds

Linux 2.6.31-rc2

2009-07-04T17:58:48+00:00

kbuild: finally remove the obsolete variable $TOPDIR

2009-06-26T22:27:17+00:00

TOPDIR is obsolete, it can be finally removed now.

Signed-off-by: WANG Cong 
Signed-off-by: Sam Ravnborg

Kbuild: Disable the -Wformat-security gcc flag

2009-06-26T22:15:27+00:00

Some distributions have enabled the gcc flag -Wformat-security by default.
This results in a number of warnings about format arguments to functions,
sometimes in cases where fixing the warning is not likely to actually fix a
bug.  Instead of hand patching a dozens of places (possibly more) that produce
warnings that get ignored anyway we just turn off the flag in the Makefile.

Signed-off-by: Floris Kraak 
Signed-off-by: Pekka Enberg 
Signed-off-by: Sam Ravnborg

Linux 2.6.31-rc1

2009-06-24T23:25:37+00:00

gcov: add gcov profiling infrastructure

2009-06-18T20:03:57+00:00

Enable the use of GCC's coverage testing tool gcov [1] with the Linux
kernel.  gcov may be useful for:

 * debugging (has this code been reached at all?)
 * test improvement (how do I change my test to cover these lines?)
 * minimizing kernel configurations (do I need this option if the
   associated code is never run?)

The profiling patch incorporates the following changes:

 * change kbuild to include profiling flags
 * provide functions needed by profiling code
 * present profiling data as files in debugfs

Note that on some architectures, enabling gcc's profiling option
"-fprofile-arcs" for the entire kernel may trigger compile/link/
run-time problems, some of which are caused by toolchain bugs and
others which require adjustment of architecture code.

For this reason profiling the entire kernel is initially restricted
to those architectures for which it is known to work without changes.
This restriction can be lifted once an architecture has been tested
and found compatible with gcc's profiling. Profiling of single files
or directories is still available on all platforms (see config help
text).

[1] http://gcc.gnu.org/onlinedocs/gcc/Gcov.html

Signed-off-by: Peter Oberparleiter 
Cc: Andi Kleen 
Cc: Huang Ying 
Cc: Li Wei 
Cc: Michael Ellerman 
Cc: Ingo Molnar 
Cc: Heiko Carstens 
Cc: Martin Schwidefsky 
Cc: Rusty Russell 
Cc: WANG Cong 
Cc: Sam Ravnborg 
Cc: Jeff Dike 
Cc: Al Viro 
Signed-off-by: Andrew Morton 
Signed-off-by: Linus Torvalds

Merge branch 'master' of git://git.kernel.org/pub/scm/linux/kernel/git/sam/kbuild-next

2009-06-14T21:12:18+00:00

* 'master' of git://git.kernel.org/pub/scm/linux/kernel/git/sam/kbuild-next: (53 commits)
  .gitignore: ignore *.lzma files
  kbuild: add generic --set-str option to scripts/config
  kbuild: simplify argument loop in scripts/config
  kbuild: handle non-existing options in scripts/config
  kallsyms: generalize text region handling
  kallsyms: support kernel symbols in Blackfin on-chip memory
  documentation: make version fix
  kbuild: fix a compile warning
  gitignore: Add GNU GLOBAL files to top .gitignore
  kbuild: fix delay in setlocalversion on readonly source
  README: fix misleading pointer to the defconf directory
  vmlinux.lds.h update
  kernel-doc: cleanup perl script
  Improve vmlinux.lds.h support for arch specific linker scripts
  kbuild: fix headers_exports with boolean expression
  kbuild/headers_check: refine extern check
  kbuild: fix "Argument list too long" error for "make headers_check",
  ignore *.patch files
  Remove bashisms from scripts
  menu: fix embedded menu presentation
  ...