When you put
  .section ".foo"
in an assembly file instead of
  .section "foo", "ax"
, one of the possible symptoms is that modpost will see an
ld-generated section name ".foo.1" in section_rel() or section_rela().
But this heuristic has two problems: it will miss a bad section that
has no relocations, and it will incorrectly flag many gcc-generated
sections as bad when compiling with -ffunction-sections
-fdata-sections.

On mips it fixes a lot of bogus warnings with gcc 4.4.0 lije this one:
WARNING: crypto/cryptd.o (.text.T.349): unexpected section name.

So instead of checking whether the section name matches a particular
pattern, we directly check for a missing SHF_ALLOC in the section
flags.
Signed-off-by: NAnders Kaseorg <andersk@mit.edu>
Tested-by: NRalf Baechle <ralf@linux-mips.org>
Signed-off-by: NSam Ravnborg <sam@ravnborg.org>

There is some confusion on naming of the head section.
Correct naming is .head.text.

Fix comment so we use correct naming.
Signed-off-by: NSam Ravnborg <sam@ravnborg.org>

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: NCedric Hombourger <chombourger@gmail.com>
Cc: <stable@kernel.org>
Signed-off-by: NAndrew Morton <akpm@linux-foundation.org>
Signed-off-by: NSam Ravnborg <sam@ravnborg.org>

The old refok sections

  .text.init.refok
  .data.init.refok
  .exit.text.refok

have been deprecated since commit
312b1485.  After the other patches in
this patch series nothing is put in these sections, so clean things up
by eliminating all the remaining references to them.
Signed-off-by: NTim Abbott <tabbott@mit.edu>
Acked-by: NSam Ravnborg <sam@ravnborg.org>
Signed-off-by: NLinus Torvalds <torvalds@linux-foundation.org>

new_module() itself already calls strdup() on its modname parameter.
Signed-off-by: NJan Beulich <jbeulich@novell.com>
Signed-off-by: NSam Ravnborg <sam@ravnborg.org>

With CONFIG_MODVERSIONS, we version 'struct module' using a dummy
export, but other things matter too:

1) 'struct modversion_info' determines the layout of the __versions section,
2) 'struct kernel_param' determines the layout of the __params section,
3) 'struct kernel_symbol' determines __ksymtab*.
4) 'struct marker' determines __markers.
5) 'struct tracepoint' determines __tracepoints.

So we rename 'struct_module' to 'module_layout' and include these in
the signature.  Now it's general we can add others later on without
confusion.
Signed-off-by: NRusty Russell <rusty@rustcorp.com.au>

Impact: fix link failure on certain toolchains with specific configs

Recent percpu change made x86_64 split .data.init section into three
separate segments - data.init, percpu and data.init2.  data.init2 gets
.data.nosave and .bss.* and is followed by .notes segment.  Depending
on configuration both segments might contain no data, in which case
the tool chain makes the section header to contain offset beyond the
end of the file.

modpost isn't too happy about it and fails build - as reported by
Pawel Dziekonski:

    Building modules, stage 2.
    MODPOST 416 modules
    FATAL: vmlinux is truncated. sechdrs[i].sh_offset=10354688 >
    sizeof(*hrd)=64
    make[1]: *** [__modpost] Error 1

Teach modpost that NOBITS section may point beyond the end of the file
and that .modinfo can't be NOBITS.
Reported-by: NPawel Dziekonski <dzieko@gmail.com>
Signed-off-by: NTejun Heo <tj@kernel.org>
Signed-off-by: NIngo Molnar <mingo@elte.hu>

We need to add a flag for all code that is in the drivers/staging/
directory to prevent all other kernel developers from worrying about
issues here, and to notify users that the drivers might not be as good
as they are normally used to.

Based on code from Andreas Gruenbacher and Jeff Mahoney to provide a
TAINT flag for the support level of a kernel module in the Novell
enterprise kernel release.

This is the code that actually modifies the modules, adding the flag to
any files in the drivers/staging directory.

Cc: Andreas Gruenbacher <agruen@suse.de>
Cc: Jeff Mahoney <jeffm@suse.de>
Signed-off-by: NGreg Kroah-Hartman <gregkh@suse.de>

* 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 d35cb360)

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: NMathieu Desnoyers <mathieu.desnoyers@polymtl.ca>
Tested-by: N"Theodore Ts'o" <tytso@mit.edu>
CC: Greg KH <greg@kroah.com>
CC: David Smith <dsmith@redhat.com>
CC: Roland McGrath <roland@redhat.com>
CC: Sam Ravnborg <sam@ravnborg.org>
CC: Wenji Huang <wenji.huang@oracle.com>
CC: Takashi Nishiie <t-nishiie@np.css.fujitsu.com>
Signed-off-by: NLinus Torvalds <torvalds@linux-foundation.org>

Spelling fixes in scripts/mod/modpost.c
Signed-off-by: NBen Dooks <ben-linux@fluff.org>
Cc: Rusty Russell <rusty@rustcorp.com.au>
Cc: Sam Ravnborg <sam@ravnborg.org>
Signed-off-by: NAndrew Morton <akpm@linux-foundation.org>
Signed-off-by: NLinus Torvalds <torvalds@linux-foundation.org>

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
b2e3e658

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 <roland@redhat.com>
Wenji Huang <wenji.huang@oracle.com>
and
Takashi Nishiie <t-nishiie@np.css.fujitsu.com>

for providing the individual fixes.

- Changelog :
  - Integrated Takashi's Makefile modification to clear Module.markers upon
    make clean.
Signed-off-by: NMathieu Desnoyers <mathieu.desnoyers@polymtl.ca>
Cc: Roland McGrath <roland@redhat.com>
Cc: Wenji Huang <wenji.huang@oracle.com>
Cc: Takashi Nishiie <t-nishiie@np.css.fujitsu.com>
Cc: <stable@kernel.org>		[2.6.25.x, 2.6.26.x]
Signed-off-by: NAndrew Morton <akpm@linux-foundation.org>
Signed-off-by: NLinus Torvalds <torvalds@linux-foundation.org>

Kumar Gala <galak@kernel.crashing.org> 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: NSam Ravnborg <sam@ravnborg.org>
Cc: Kumar Gala <galak@kernel.crashing.org>
Cc: Paul Mackerras <paulus@samba.org>

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 <linux/init.h> 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: NAndi Kleen <ak@linux.intel.com>
Signed-off-by: NSam Ravnborg <sam@ravnborg.org>

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

This fixes allmodconfig build on my box.
Signed-off-by: NSam Ravnborg <sam@ravnborg.org>

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: NRichard Hacker <lerichi@gmx.net>
Signed-off-by: NSam Ravnborg <sam@ravnborg.org>

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: NSam Ravnborg <sam@ravnborg.org>
Cc: Adrian Bunk <bunk@kernel.org>

The module alias support in the kernel have a consistency
check where it is checked that the size of a structure
in the kernel and on the build host are the same.
For cross builds this check does not make sense so detect
when we do cross builds and silently skip the check in these
situations.
This fixes a build bug for a wireless driver when cross building
for arm.
Acked-by: NMichael Buesch <mb@bu3sch.de>
Tested-by: NGordon Farquharson <gordonfarquharson@gmail.com>
Signed-off-by: NSam Ravnborg <sam@ravnborg.org>
Cc: stable@kernel.org

XXXINIT_TO_INIT and XXXEXIT_TO_EXIT warnings use the reversed symbol name order
in the suggestion, e.g.:

    WARNING: vmlinux.o(.meminit.text+0x36c): Section mismatch in reference from the function free_area_init_core() to the function .init.text:setup_usemap()
    The function __meminit free_area_init_core() references
    a function __init setup_usemap().
    If free_area_init_core is only used by setup_usemap then
    annotate free_area_init_core with a matching annotation.
Signed-off-by: NGeert Uytterhoeven <geert@linux-m68k.org>
Signed-off-by: NSam Ravnborg <sam@ravnborg.org>

This adds some new magic in the MODPOST phase for CONFIG_MARKERS.  Analogous
to the Module.symvers file, the build will now write a Module.markers file
when CONFIG_MARKERS=y is set.  This file lists the name, defining module, and
format string of each marker, separated by \t characters.  This simple text
file can be used by offline build procedures for instrumentation code,
analogous to how System.map and Module.symvers can be useful to have for
kernels other than the one you are running right now.

The strings are made easy to extract by having the __trace_mark macro define
the name and format together in a single array called __mstrtab_* in the
__markers_strings section.  This is straightforward and reliable as long as
the marker structs are always defined by this macro.  It is an unreasonable
amount of hairy work to extract the string pointers from the __markers section
structs, which entails handling a relocation type for every machine under the
sun.

Mathieu :
- Ran through checkpatch.pl
Signed-off-by: NRoland McGrath <roland@redhat.com>
Signed-off-by: NMathieu Desnoyers <mathieu.desnoyers@polymtl.ca>
Cc: David Smith <dsmith@redhat.com>
Cc: Sam Ravnborg <sam@ravnborg.org>
Signed-off-by: NAndrew Morton <akpm@linux-foundation.org>
Signed-off-by: NLinus Torvalds <torvalds@linux-foundation.org>

modpost: Use warn() for announcing section mismatches, for easy grepping for
warnings in build logs.

Also change an existing call from fprintf() to warn() while we're at it.
Signed-off-by: NGeert Uytterhoeven <Geert.Uytterhoeven@sonycom.com>
Signed-off-by: NSam Ravnborg <sam@ravnborg.org>

If we cannot determine the symbol then print
(unknown) to hint the reader that we failed to
find the symbol.
This happens with REL relocation records
in arm object files.
Signed-off-by: NSam Ravnborg <sam@ravnborg.org>

We have several legitimate uses where we export symbols
annotated with one of:
__devinit, __cpuinit, __meminit and their exit counterpart.
So let's stop warning about those being exported in favour
of adding all sorts of workaround to silence the warning.
Signed-off-by: NSam Ravnborg <sam@ravnborg.org>

We have too many section mismatches detected at the moment.
So silence modpost and prevent the option from being
set in a typical allyesconfig build.

Tell the user how to see all the deteils in the summary
message from modpost.
Signed-off-by: NSam Ravnborg <sam@ravnborg.org>

If there is a mixture of specifying sections for code in gcc
and assembler then if the assembler code do not add
the "ax" flags the linker will see this as two different sections
and generate unique sections for each. ld does so by adding a dot
and a number.
Teach modpost to warn if a section shows up that match this
pattern - but do this only for non-debug sections.

It will result in warnings like this:

WARNING: vmlinux.o (.sched.text.1): 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 <linux/init.h> contains
section definitions for use in .S files.

All warnings seen with a defconfig build for:
x86 (32+64bit) and sparc64 has been fixed (via respective maintainers).

arm, powerpc (64 bit), s390 (32 bit), ia64, alpha, sh4 checked - no
warnings seen with a defconfig build.
Signed-off-by: NSam Ravnborg <sam@ravnborg.org>

If the config option CONFIG_SECTION_MISMATCH is not set and
we see a Section mismatch present the following to the user:

modpost: Found 1 section mismatch(es).
To see additional details select "Enable full Section mismatch analysis"
in the Kernel Hacking menu (CONFIG_SECTION_MISMATCH).

If the option CONFIG_SECTION_MISMATCH is selected
then be verbose in the Section mismatch reporting from mdopost.
Sample outputs:

WARNING: o-x86_64/vmlinux.o(.text+0x7396): Section mismatch in reference from the function discover_ebda() to the variable .init.data:ebda_addr
The function  discover_ebda() references
the variable __initdata ebda_addr.
This is often because discover_ebda lacks a __initdata
annotation or the annotation of ebda_addr is wrong.

WARNING: o-x86_64/vmlinux.o(.data+0x74d58): Section mismatch in reference from the variable pci_serial_quirks to the function .devexit.text:pci_plx9050_exit()
The variable pci_serial_quirks references
the function __devexit pci_plx9050_exit()
If the reference is valid then annotate the
variable with __exit* (see linux/init.h) or name the variable:
*driver, *_template, *_timer, *_sht, *_ops, *_probe, *_probe_one, *_console,

WARNING: o-x86_64/vmlinux.o(__ksymtab+0x630): Section mismatch in reference from the variable __ksymtab_arch_register_cpu to the function .cpuinit.text:arch_register_cpu()
The symbol arch_register_cpu is exported and annotated __cpuinit
Fix this by removing the __cpuinit annotation of arch_register_cpu or drop the export.
Signed-off-by: NSam Ravnborg <sam@ravnborg.org>

Remove the deprecated __attribute_used__.

[Introduce __section in a few places to silence checkpatch /sam]
Signed-off-by: NAdrian Bunk <bunk@kernel.org>
Signed-off-by: NSam Ravnborg <sam@ravnborg.org>

Refactor code so the warning report function
does nothing else than reporting warnings.
As a side effect some other code paths were cleaned
up by this.
Signed-off-by: NSam Ravnborg <sam@ravnborg.org>

Introducing helpers to retreive symbol and section
names cleaned up the code a bit.
Signed-off-by: NSam Ravnborg <sam@ravnborg.org>

The typical layout is now:
WARNING: vmlinux.o(.text+0x372ec): Section mismatch: reference to .devinit.text:pci_scan_one_pbm in 'psycho_scan_bus'

This is first step towards more readable warnings.
Signed-off-by: NSam Ravnborg <sam@ravnborg.org>

Introducing separate sections for __dev* (HOTPLUG),
__cpu* (HOTPLUG_CPU) and __mem* (MEMORY_HOTPLUG)
allows us to do a much more reliable Section mismatch
check in modpost. We are no longer dependent on the actual
configuration of for example HOTPLUG.

This has the effect that all users see much more
Section mismatch warnings than before because they
were almost all hidden when HOTPLUG was enabled.
The advantage of this is that when building a piece
of code then it is much more likely that the Section
mismatch errors are spotted and the warnings will be
felt less random of nature.
Signed-off-by: NSam Ravnborg <sam@ravnborg.org>
Cc: Greg KH <greg@kroah.com>
Cc: Randy Dunlap <randy.dunlap@oracle.com>
Cc: Adrian Bunk <bunk@kernel.org>

Now that match() is introduced use it consistently so
we can share the section name definitions.
Signed-off-by: NSam Ravnborg <sam@ravnborg.org>

Change the logic in modpost so we identify all the
bad combinations of sections that refer to other
sections.
Compared to the previous approach we are much less
dependent on knowledge of what additional sections
the tool chain uses and thus we can keep the false
positives low.

The implmentation is changed to use a table based
lookup and we now check all combinations in first
pass so we no longer need separate passes for init
and exit sections.

Tested that the same warnings are generated for
an allyesconfig build without CONFIG_HOTPLUG.
Signed-off-by: NSam Ravnborg <sam@ravnborg.org>
Cc: Randy Dunlap <randy.dunlap@oracle.com>
Cc: Adrian Bunk <bunk@kernel.org>

Split a too long function up in smaller bits to make
prgram logic easier to follow.
A few related changes done due to parameter
changes.

No functional changes.
Signed-off-by: NSam Ravnborg <sam@ravnborg.org>

The relocation record sometimes contained an address
which was not an exactly match for a symbol.

Implment some simple logic such that if there
is a symbol within 20 bytes of the address contained
in the relocation record then print the name of this
symbol.

With this change modpost could find symbol names
for the remaining .init.text symbols in my
allyesconfig build for x86_64.
Signed-off-by: NSam Ravnborg <sam@ravnborg.org>

It is very convinient to say:
scripts/mod/modpost mm/built-in.o

to check if any section mismatch errors occured
in mm/ (as an example).
Fix it so this is possible again.
Signed-off-by: NSam Ravnborg <sam@ravnborg.org>

akpm complained about overly long lines in modpost.c and
when started additional style issues were fixed:

o Updated my copyright
o Removed unneeded {}
o Drop assignments in if ()
o Spaces around operators
o Break long lines
o locate * near variable not type
o Fix a format specifier for sizeof()
o Corrected placement of '{' and '}'
o spaces to tabs (but use tabs only for indention)

modpost.c is not checkpatch clean. Readability were favoured
on top of checkpatch compliance.
But checkpatch were used to find additional stuff to clean up.
Signed-off-by: NSam Ravnborg <sam@ravnborg.org>

When passing an file name > 1k the stack could be overflowed.
Not really a security issue, but still better plugged.
Signed-off-by: NAndi Kleen <ak@suse.de>
Signed-off-by: NSam Ravnborg <sam@ravnborg.org>

Fix wrong format strings in modpost exposed by the previous patch.
Including one missing argument -- some random data was printed instead.
Signed-off-by: NAndi Kleen <ak@suse.de>
Signed-off-by: NSam Ravnborg <sam@ravnborg.org>

This way gcc can warn for wrong format strings
Signed-off-by: NAndi Kleen <ak@suse.de>
Signed-off-by: NSam Ravnborg <sam@ravnborg.org>

When part of build an external module tree, modpost first reads in the
kernel's and then the external tree's Module.symvers files.  From these files
it establishes a symbol => module mapping.  When it later reads in each module
built and processes the symbols it finds, it discovers the symbol=>module
mapping from Module.symvers and leaves it as it is.

The problem comes with a module has been re-named or a symbol has moved from
one module to another, since the Module.symvers file was generated.  modpost
does not update the symbol=>module mapping when it finds the new location of
the symbol when scanning the newly built modules.  This results in the module
containing incorrect dependency information and the new Module.symvers file
written by modpost will also contain the incorrect mappings, perpetuating the
problem to the next build, and so on.

When building the out of kernel development tree for kernel subsystem, like
v4l-dvb or ALSA, deleting the external Module.symvers file before building
(which the kernel build system doesn't do and shouldn't be necessary anyway),
won't fix the problem.  modpost still reads the kernel's Module.symvers, and
since we a building a kernel subsystem, it will define the same symbols as the
external modules.
Signed-off-by: NTrent Piepho <xyzzy@speakeasy.org>
Signed-off-by: NSam Ravnborg <sam@ravnborg.org>