linux-toradex.git/scripts/mod/modpost.c, branch v2.6.27.56

kbuild: Fix modpost segfault

2010-08-02T17:18:51+00:00

commit 1c938663d58b5b2965976a6f54cc51b5d6f691aa upstream.

Alan  writes:

> program: /home/alan/GitTrees/linux-2.6-mid-ref/scripts/mod/modpost -o
> Module.symvers -S vmlinux.o
>
> Program received signal SIGSEGV, Segmentation fault.

It just hit me.
It's the offset calculation in reloc_location() which overflows:
        return (void *)elf->hdr + sechdrs[section].sh_offset +
               (r->r_offset - sechdrs[section].sh_addr);

E.g. for the first rodata r entry:
r->r_offset < sechdrs[section].sh_addr
and the expression in the parenthesis produces 0xFFFFFFE0 or something
equally wise.

Reported-by: Alan 
Signed-off-by: Krzysztof Hałasa 
Tested-by: Alan 
Signed-off-by: Michal Marek 
Signed-off-by: Greg Kroah-Hartman

kbuild: fix Module.markers permission error under cygwin

2009-05-08T21:54:34+00:00

commit 99e3a1eb3c22bb671c6f3d22d8244bfc9fad8185 upstream.

While building the kernel, we end-up calling modpost with -K and -M
options for the same file (Modules.markers).  This is resulting in
modpost's main function calling read_markers() and then write_markers() on
the same file.

We then have read_markers() mmap'ing the file, and writer_markers()
opening that same file for writing.

The issue is that read_markers() exits without munmap'ing the file and is
as a matter holding a reference on Modules.markers.  When write_markers()
is opening that very same file for writing, we still have a reference on
it and cygwin (Windows?) is then making fopen() fail with EPERM.

Calling release_file() before exiting read_markers() clears that reference
(and memory leak) and fopen() then succeeds.

Tested on both cygwin (1.3.22) and Linux.  Also ran modpost within
valgrind on Linux to make sure that the munmap'ed file was not accessed
after read_markers()

Signed-off-by: Cedric Hombourger 
Cc: 
Signed-off-by: Andrew Morton 
Signed-off-by: Sam Ravnborg 
Signed-off-by: Greg Kroah-Hartman

Marker depmod fix core kernel list

2008-10-06T23:34:19+00:00

* Theodore Ts'o (tytso@mit.edu) wrote:
>
> I've been playing with adding some markers into ext4 to see if they
> could be useful in solving some problems along with Systemtap.  It
> appears, though, that as of 2.6.27-rc8, markers defined in code which is
> compiled directly into the kernel (i.e., not as modules) don't show up
> in Module.markers:
>
> kvm_trace_entryexit arch/x86/kvm/kvm-intel  %u %p %u %u %u %u %u %u
> kvm_trace_handler arch/x86/kvm/kvm-intel  %u %p %u %u %u %u %u %u
> kvm_trace_entryexit arch/x86/kvm/kvm-amd  %u %p %u %u %u %u %u %u
> kvm_trace_handler arch/x86/kvm/kvm-amd  %u %p %u %u %u %u %u %u
>
> (Note the lack of any of the kernel_sched_* markers, and the markers I
> added for ext4_* and jbd2_* are missing as wel.)
>
> Systemtap apparently depends on in-kernel trace_mark being recorded in
> Module.markers, and apparently it's been claimed that it used to be
> there.  Is this a bug in systemtap, or in how Module.markers is getting
> built?   And is there a file that contains the equivalent information
> for markers located in non-modules code?

I think the problem comes from "markers: fix duplicate modpost entry"
(commit d35cb360c29956510b2fe1a953bd4968536f7216)

Especially :

  -   add_marker(mod, marker, fmt);
  +   if (!mod->skip)
  +     add_marker(mod, marker, fmt);
    }
    return;
   fail:

Here is a fix that should take care if this problem.

Thanks for the bug report!

Signed-off-by: Mathieu Desnoyers 
Tested-by: "Theodore Ts'o" 
CC: Greg KH 
CC: David Smith 
CC: Roland McGrath 
CC: Sam Ravnborg 
CC: Wenji Huang 
CC: Takashi Nishiie 
Signed-off-by: Linus Torvalds

scripts/mod/modpost.c: fix spelling of module and happens

2008-07-30T16:41:46+00:00

Spelling fixes in scripts/mod/modpost.c

Signed-off-by: Ben Dooks 
Cc: Rusty Russell 
Cc: Sam Ravnborg 
Signed-off-by: Andrew Morton 
Signed-off-by: Linus Torvalds

markers: fix duplicate modpost entry

2008-07-22T16:59:41+00:00

When a kernel was rebuilt, the previous Module.markers was not cleared.
It caused markers with different format strings to appear as duplicates
when a markers was changed.  This problem is present since
scripts/mod/modpost.c started to generate Module.markers, commit
b2e3e658b344c6bcfb8fb694100ab2f2b5b2edb0

It therefore applies to 2.6.25, 2.6.26 and linux-next.

I merely merged the patches from Roland, Wenji and Takashi here.

Credits to
Roland McGrath 
Wenji Huang 
and
Takashi Nishiie 

for providing the individual fixes.

- Changelog :
  - Integrated Takashi's Makefile modification to clear Module.markers upon
    make clean.

Signed-off-by: Mathieu Desnoyers 
Cc: Roland McGrath 
Cc: Wenji Huang 
Cc: Takashi Nishiie 
Cc: 		[2.6.25.x, 2.6.26.x]
Signed-off-by: Andrew Morton 
Signed-off-by: Linus Torvalds

kbuild: ignore powerpc specific symbols in modpost

2008-06-12T14:41:48+00:00

Kumar Gala  wrote:
We have a case in powerpc in which we want to link some library
routines with all module objects.  The routines are intended for
handling out-of-line function call register save/restore so having
them as EXPORT_SYMBOL() is counter productive (we do also need to
link the same "library" code into the kernel).

Without this patch a powerpc build would error out and fail
to build modules with the added register save/restore module.

There were two obvious solutions:
1) To link the .o file before the modpost stage
2) To ignore the symbols in modpost

Option 1) was ruled out because we do not have any separate
linking stage for single file modules.

This patch implements option 2 - and do so only for powerpc.

The symbols we ignore are all undefined symbols named:
_restgpr_*, _savegpr_*, _rest32gpr_*, _save32gpr_*

Signed-off-by: Sam Ravnborg 
Cc: Kumar Gala 
Cc: Paul Mackerras

kbuild: disable modpost warnings for linkonce sections

2008-05-11T08:10:51+00:00

Disable modpost warnings for linkonce sections

My build gives lots of warnings like

WARNING: sound/core/snd.o (.gnu.linkonce.wi.mpspec_def.h.30779716): unexpected section name.
The (.[number]+) following section name are ld generated and not expected.
Did you forget to use "ax"/"aw" in a .S file?
Note that for example  contains
section definitions for use in .S files.

But for .linkonce. duplicated sections are actually ok and expected.
So just disable the warning for this case.

Signed-off-by: Andi Kleen 
Signed-off-by: Sam Ravnborg

kbuild: soften MODULE_LICENSE check

2008-04-26T19:07:26+00:00

Only modules that has other MODULE_* content
shall have the MODULE_LICENSE() tag.

This fixes allmodconfig build on my box.

Signed-off-by: Sam Ravnborg

kbuild: support loading extra symbols in modpost

2008-04-25T18:35:47+00:00

This patch adds a new command line option -E to modpost, expecting a symbol
file as an argument which is read prior to symbol processing. -E can be
supplied multiple times for as many files as is needed.

When building kernel modules that depend on other modules not in the main
kernel tree, modpost complains about undefined symbols:
# make -C /path/to/linux/kernel M=/path/to/my/module
...
Building modules, stage 2.
....
WARNING: "rt_copy_buf" [/home/rich/osc_etl_rtw/osc_kmod.ko] undefined!
...etc

This situation occurs when modpost processes the new module's symbols. When
it finds symbols not exported by the mainline kernel, it issues this warning.

The patch adds a new command line option -e to modpost which expects a symbol
file as an argument. The symbols listed in this file are added to modpost's
symbol tables during startup. -e can be supplied as often as required.

This patch works together with the second patch. It introduces a new make
variable, KBUILD_EXTRA_SYMBOLS, which is used when calling modpost.

Signed-off-by: Richard Hacker 
Signed-off-by: Sam Ravnborg

kbuild: error out on missing MODULE_LICENSE

2008-04-25T18:13:30+00:00

Adrian Bunk suggested a build time check for
missing MODULE_LICENSE annotation in modules.
The build time check is fatal as we really
want this fixed for all modules.
In-tree modules should all have been fixed up by now.

Signed-off-by: Sam Ravnborg 
Cc: Adrian Bunk