Commit Graph

243 Commits

Author SHA1 Message Date
Kees Cook 3e2e857f9c module: Add module name to modinfo
Accessing the mod structure (e.g. for mod->name) prior to having completed
check_modstruct_version() can result in writing garbage to the error logs
if the layout of the mod structure loaded from disk doesn't match the
running kernel's mod structure layout. This kind of mismatch will become
much more likely if a kernel is built with different randomization seed
for the struct layout randomization plugin.

Instead, add and use a new modinfo string for logging the module name.

Signed-off-by: Kees Cook <keescook@chromium.org>
Signed-off-by: Jessica Yu <jeyu@redhat.com>
2017-05-23 14:08:31 -07:00
Josh Poimboeuf e390f9a968 objtool, modules: Discard objtool annotation sections for modules
The '__unreachable' and '__func_stack_frame_non_standard' sections are
only used at compile time.  They're discarded for vmlinux but they
should also be discarded for modules.

Since this is a recurring pattern, prefix the section names with
".discard.".  It's a nice convention and vmlinux.lds.h already discards
such sections.

Also remove the 'a' (allocatable) flag from the __unreachable section
since it doesn't make sense for a discarded section.

Suggested-by: Linus Torvalds <torvalds@linux-foundation.org>
Signed-off-by: Josh Poimboeuf <jpoimboe@redhat.com>
Cc: Jessica Yu <jeyu@redhat.com>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Fixes: d1091c7fa3 ("objtool: Improve detection of BUG() and other dead ends")
Link: http://lkml.kernel.org/r/20170301180444.lhd53c5tibc4ns77@treble
Signed-off-by: Ingo Molnar <mingo@kernel.org>
2017-03-01 20:32:25 +01:00
Ard Biesheuvel 56067812d5 kbuild: modversions: add infrastructure for emitting relative CRCs
This add the kbuild infrastructure that will allow architectures to emit
vmlinux symbol CRCs as 32-bit offsets to another location in the kernel
where the actual value is stored. This works around problems with CRCs
being mistaken for relocatable symbols on kernels that self relocate at
runtime (i.e., powerpc with CONFIG_RELOCATABLE=y)

For the kbuild side of things, this comes down to the following:

 - introducing a Kconfig symbol MODULE_REL_CRCS

 - adding a -R switch to genksyms to instruct it to emit the CRC symbols
   as references into the .rodata section

 - making modpost distinguish such references from absolute CRC symbols
   by the section index (SHN_ABS)

 - making kallsyms disregard non-absolute symbols with a __crc_ prefix

Signed-off-by: Ard Biesheuvel <ard.biesheuvel@linaro.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2017-02-03 08:28:25 -08:00
Linus Torvalds 41e0e24b45 Merge branch 'kbuild' of git://git.kernel.org/pub/scm/linux/kernel/git/mmarek/kbuild
Pull kbuild updates from Michal Marek:

 - prototypes for x86 asm-exported symbols (Adam Borowski) and a warning
   about missing CRCs (Nick Piggin)

 - asm-exports fix for LTO (Nicolas Pitre)

 - thin archives improvements (Nick Piggin)

 - linker script fix for CONFIG_LD_DEAD_CODE_DATA_ELIMINATION (Nick
   Piggin)

 - genksyms support for __builtin_va_list keyword

 - misc minor fixes

* 'kbuild' of git://git.kernel.org/pub/scm/linux/kernel/git/mmarek/kbuild:
  x86/kbuild: enable modversions for symbols exported from asm
  kbuild: fix scripts/adjust_autoksyms.sh* for the no modules case
  scripts/kallsyms: remove last remnants of --page-offset option
  make use of make variable CURDIR instead of calling pwd
  kbuild: cmd_export_list: tighten the sed script
  kbuild: minor improvement for thin archives build
  kbuild: modpost warn if export version crc is missing
  kbuild: keep data tables through dead code elimination
  kbuild: improve linker compatibility with lib-ksyms.o build
  genksyms: Regenerate parser
  kbuild/genksyms: handle va_list type
  kbuild: thin archives for multi-y targets
  kbuild: kallsyms allow 3-pass generation if symbols size has changed
2016-12-17 16:24:13 -08:00
Nicholas Piggin d8c1eb86e9 kbuild: modpost warn if export version crc is missing
This catches the failing ceph CRC on with:

    LD      vmlinux.o
    MODPOST vmlinux.o
  WARNING: EXPORT symbol "ceph_monc_do_statfs" [vmlinux] version
  generation failed, symbol will not be versioned.

When the modules referring to exported symbols are built, there is an
existing warning for missing CRC, but it's not always the case such
any such module will be built, and in any case it is useful to get a
warning at the source.

This gets a little verbose with CONFIG_DEBUG_SECTION_MISMATCH,
producing a warning with each object linked, but I didn't think
that warranted extra complexity to avoid.

Signed-off-by: Nicholas Piggin <npiggin@gmail.com>
Signed-off-by: Michal Marek <mmarek@suse.com>
2016-11-29 15:58:57 +01:00
Heinrich Schuchardt c7d47f26df modpost: free allocated memory
valgrind complains that memory is not freed after allocation
with realloc() called from main() and write_dump().

So let us free the allocated memory properly.

Signed-off-by: Heinrich Schuchardt <xypron.glpk@gmx.de>
Signed-off-by: Rusty Russell <rusty@rustcorp.com.au>
Link: http://lkml.kernel.org/r/1470166981-6461-1-git-send-email-xypron.glpk@gmx.de
Signed-off-by: Jessica Yu <jeyu@redhat.com>
2016-11-26 11:18:01 -08:00
Chris Metcalf 6727ad9e20 nmi_backtrace: generate one-line reports for idle cpus
When doing an nmi backtrace of many cores, most of which are idle, the
output is a little overwhelming and very uninformative.  Suppress
messages for cpus that are idling when they are interrupted and just
emit one line, "NMI backtrace for N skipped: idling at pc 0xNNN".

We do this by grouping all the cpuidle code together into a new
.cpuidle.text section, and then checking the address of the interrupted
PC to see if it lies within that section.

This commit suitably tags x86 and tile idle routines, and only adds in
the minimal framework for other architectures.

Link: http://lkml.kernel.org/r/1472487169-14923-5-git-send-email-cmetcalf@mellanox.com
Signed-off-by: Chris Metcalf <cmetcalf@mellanox.com>
Acked-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Tested-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Tested-by: Daniel Thompson <daniel.thompson@linaro.org> [arm]
Tested-by: Petr Mladek <pmladek@suse.com>
Cc: Aaron Tomlin <atomlin@redhat.com>
Cc: Peter Zijlstra (Intel) <peterz@infradead.org>
Cc: "Rafael J. Wysocki" <rjw@rjwysocki.net>
Cc: Russell King <linux@arm.linux.org.uk>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: Ingo Molnar <mingo@elte.hu>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2016-10-07 18:46:30 -07:00
Alan Modra c153693d7e powerpc: Simplify module TOC handling
PowerPC64 uses the symbol .TOC. much as other targets use
_GLOBAL_OFFSET_TABLE_. It identifies the value of the GOT pointer (or in
powerpc parlance, the TOC pointer). Global offset tables are generally
local to an executable or shared library, or in the kernel, module. Thus
it does not make sense for a module to resolve a relocation against
.TOC. to the kernel's .TOC. value. A module has its own .TOC., and
indeed the powerpc64 module relocation processing ignores the kernel
value of .TOC. and instead calculates a module-local value.

This patch removes code involved in exporting the kernel .TOC., tweaks
modpost to ignore an undefined .TOC., and the module loader to twiddle
the section symbol so that .TOC. isn't seen as undefined.

Note that if the kernel was compiled with -msingle-pic-base then ELFv2
would not have function global entry code setting up r2. In that case
the module call stubs would need to be modified to set up r2 using the
kernel .TOC. value, requiring some of this code to be reinstated.

mpe: Furthermore a change in binutils master (not yet released) causes
the current way we handle the TOC to no longer work when building with
MODVERSIONS=y and RELOCATABLE=n. The symptom is that modules can not be
loaded due to there being no version found for TOC.

Cc: stable@vger.kernel.org # 3.16+
Signed-off-by: Alan Modra <amodra@gmail.com>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
2016-01-21 14:10:56 +11:00
Noam Camus d1189c63ea scripts: [modpost] add new sections to white list
In our ARC toolchain the default linker script includes special
sections used for code and data located in special fast memory.
To avoid warnings we add these sections i.e. .cmem* and .fmt_slot*
to white list.

Signed-off-by: Noam Camus <noamc@ezchip.com>
Cc: Rusty Russell <rusty@rustcorp.com.au>
Cc: Quentin Casasnovas <quentin.casasnovas@oracle.com>
Signed-off-by: Rusty Russell <rusty@rustcorp.com.au>
2015-10-26 20:38:43 +10:30
Nicolas Boichat 47490ec141 modpost: Add flag -E for making section mismatches fatal
The section mismatch warning can be easy to miss during the kernel build
process. Allow it to be marked as fatal to be easily caught and prevent
bugs from slipping in.

Setting CONFIG_SECTION_MISMATCH_WARN_ONLY=y causes these warnings to be
non-fatal, since there are a number of section mismatches when using
allmodconfig on some architectures, and we do not want to break these
builds by default.

Signed-off-by: Nicolas Boichat <drinkcat@chromium.org>
Change-Id: Ic346706e3297c9f0d790e3552aa94e5cff9897a6
Signed-off-by: Rusty Russell <rusty@rustcorp.com.au>
2015-10-06 10:46:21 +10:30
Takashi Iwai 5cfb203a30 modpost: abort if a module symbol is too long
Module symbols have a limited length, but currently the build system
allows the build finishing even if the driver code contains a too long
symbol name, which eventually overflows the modversion_info[] item.
The compiler may catch at compiling *.mod.c like
  CC      xxx.mod.o
  xxx.mod.c:18:16: warning: initializer-string for array of chars is too long
but it's merely a warning.

This patch adds the check of the symbol length in modpost and stops
the build properly.

Currently MODULE_NAME_LEN is defined in modpost.c instead of referring
to the definition in kernel header because including linux/module.h is
messy and we must cover cross-compilation.

Signed-off-by: Takashi Iwai <tiwai@suse.de>
Signed-off-by: Rusty Russell <rusty@rustcorp.com.au>
2015-08-08 19:52:08 +09:30
Chris Metcalf 673c2c34f6 modpost: work correctly with tile coldtext sections
The tilegx and tilepro compilers use .coldtext for their unlikely
executed text section name, so an __attribute__((cold)) function
will (when compiled with higher optimization levels) land in
the .coldtext section.

Modify modpost to add .coldtext to the set of OTHER_TEXT_SECTIONS
so we don't get warnings about referencing such a section in an
__ex_table block, and then also modify arch/tile/lib/memcpy_user_64.c
so that it uses plain ".coldtext" instead of ".coldtext.memcpy".
The latter naming is a relic of an earlier use of -ffunction-sections,
which we no longer use by default.

Signed-off-by: Chris Metcalf <cmetcalf@ezchip.com>
Acked-by: Rusty Russell <rusty@rustcorp.com.au>
2015-07-08 18:53:49 -04:00
Paul Gortmaker 4a3893d069 modpost: don't emit section mismatch warnings for compiler optimizations
Currently an allyesconfig build [gcc-4.9.1] can generate the following:

   WARNING: vmlinux.o(.text.unlikely+0x3864): Section mismatch in
   reference from the function cpumask_empty.constprop.3() to the
   variable .init.data:nmi_ipi_mask

which comes from the cpumask_empty usage in arch/x86/kernel/nmi_selftest.c.

Normally we would not see a symbol entry for cpumask_empty since it is:

	static inline bool cpumask_empty(const struct cpumask *srcp)

however in this case, the variant of the symbol gets emitted when GCC does
constant propagation optimization.

Fix things up so that any locally optimized constprop variants don't warn
when accessing variables that live in the __init sections.

Signed-off-by: Paul Gortmaker <paul.gortmaker@windriver.com>
Signed-off-by: Rusty Russell <rusty@rustcorp.com.au>
2015-04-22 17:31:34 +09:30
Paul Gortmaker 09c20c032b modpost: expand pattern matching to support substring matches
Currently the match() function supports a leading * to match any
prefix and a trailing * to match any suffix.  However there currently
is not a combination of both that can be used to target matches of
whole families of functions that share a common substring.

Here we expand the *foo and foo* match to also support *foo* with
the goal of targeting compiler generated symbol names that contain
strings like ".constprop." and ".isra."

Signed-off-by: Paul Gortmaker <paul.gortmaker@windriver.com>
Signed-off-by: Rusty Russell <rusty@rustcorp.com.au>
2015-04-22 17:31:33 +09:30
Quentin Casasnovas c5c3439af0 modpost: do not try to match the SHT_NUL section.
Trying to match the SHT_NUL section isn't useful and causes build failures
on parisc and mn10300 since the addition of section strict white-listing
and __ex_table sanitizing.

Signed-off-by: Quentin Casasnovas <quentin.casasnovas@oracle.com>
Reported-by: Guenter Roeck <linux@roeck-us.net>
Fixes: 050e57fd59 ("modpost: add strict white-listing when referencing....")
Fixes: 52dc0595d5 ("modpost: handle relocations mismatch in __ex_table.")
Tested-by: Guenter Roeck <linux@roeck-us.net>
Signed-off-by: Rusty Russell <rusty@rustcorp.com.au>
2015-04-22 17:31:33 +09:30
Quentin Casasnovas e84048aa17 modpost: fix extable entry size calculation.
As Guenter pointed out, we were never really calculating the extable entry
size because the pointer arithmetic was simply wrong.  We want to check
we're handling the second relocation in __ex_table to infer an entry size,
but we were using (void*) pointers instead of Elf_Rel[a]* ones.

This fixes the problem by moving that check in the caller (since we can
deal with different types of relocations) and add is_second_extable_reloc()
to make the whole thing more readable.

Signed-off-by: Quentin Casasnovas <quentin.casasnovas@oracle.com>
Reported-by: Guenter Roeck <linux@roeck-us.net>
CC: Rusty Russell <rusty@rustcorp.com.au>
Signed-off-by: Rusty Russell <rusty@rustcorp.com.au>
2015-04-22 17:31:32 +09:30
Quentin Casasnovas d3df4de7eb modpost: fix inverted logic in is_extable_fault_address().
As Guenter pointed out, we want to assert that extable_entry_size has been
discovered and not the other way around.  Moreover, this sanity check is
only valid when we're not dealing with the first relocation in __ex_table,
since we have not discovered the extable entry size at that point.

This was leading to a divide-by-zero on some architectures and make the
build fail.

Signed-off-by: Quentin Casasnovas <quentin.casasnovas@oracle.com>
Reported-by: Guenter Roeck <linux@roeck-us.net>
CC: Rusty Russell <rusty@rustcorp.com.au>
Signed-off-by: Rusty Russell <rusty@rustcorp.com.au>
2015-04-22 17:31:31 +09:30
Rusty Russell 6c730bfc89 modpost: handle -ffunction-sections
52dc0595d5 introduced OTHER_TEXT_SECTIONS for identifying what
sections could validly have __ex_table entries.  Unfortunately, it
wasn't tested with -ffunction-sections, which some architectures
use.

Reported-by: kbuild test robot <fengguang.wu@intel.com>
Cc: Quentin Casasnovas <quentin.casasnovas@oracle.com>
Signed-off-by: Rusty Russell <rusty@rustcorp.com.au>
2015-04-22 17:31:31 +09:30
Thierry Reding d7e0abcf4c modpost: Whitelist .text.fixup and .exception.text
32-bit and 64-bit ARM use these sections to store executable code, so
they must be whitelisted in modpost's table of valid text sections.

Signed-off-by: Thierry Reding <treding@nvidia.com>
Signed-off-by: Rusty Russell <rusty@rustcorp.com.au>
2015-04-22 17:31:20 +09:30
Quentin Casasnovas e5d8f59a5c modpost: document the use of struct section_check.
struct section_check is used as a generic way of describing what
relocations are authorized/forbidden when running modpost.  This commit
tries to describe how each field is used.

Signed-off-by: Quentin Casasnovas <quentin.casasnovas@oracle.com>
Signed-off-by: Rusty Russell <rusty@rustcorp.com.au> (Fixed "mist"ake)
2015-04-13 21:03:04 +09:30
Quentin Casasnovas 52dc0595d5 modpost: handle relocations mismatch in __ex_table.
__ex_table is a simple table section where each entry is a pair of
addresses - the first address is an address which can fault in kernel
space, and the second address points to where the kernel should jump to
when handling that fault.  This is how copy_from_user() does not crash the
kernel if userspace gives a borked pointer for example.

If one of these addresses point to a non-executable section, something is
seriously wrong since it either means the kernel will never fault from
there or it will not be able to jump to there.  As both cases are serious
enough, we simply error out in these cases so the build fails and the
developper has to fix the issue.

In case the section is executable, but it isn't referenced in our list of
authorized sections to point to from __ex_table, we just dump a warning
giving more information about it.  We do this in case the new section is
executable but isn't supposed to be executed by the kernel.  This happened
with .altinstr_replacement, which is executable but is only used to copy
instructions from - we should never have our instruction pointer pointing
in .altinstr_replacement.  Admitedly, a proper fix in that case would be to
just set .altinstr_replacement NX, but we need to warn about future cases
like this.

Signed-off-by: Quentin Casasnovas <quentin.casasnovas@oracle.com>
Signed-off-by: Rusty Russell <rusty@rustcorp.com.au> (added long casts)
2015-04-13 21:03:03 +09:30
Quentin Casasnovas c7a65e0645 modpost: mismatch_handler: retrieve tosym information only when needed.
Signed-off-by: Quentin Casasnovas <quentin.casasnovas@oracle.com>
Signed-off-by: Rusty Russell <rusty@rustcorp.com.au>
2015-04-13 21:03:01 +09:30
Quentin Casasnovas 356ad53812 modpost: factorize symbol pretty print in get_pretty_name().
Signed-off-by: Quentin Casasnovas <quentin.casasnovas@oracle.com>
Signed-off-by: Rusty Russell <rusty@rustcorp.com.au>
2015-04-13 21:03:00 +09:30
Quentin Casasnovas 644e8f14cb modpost: add handler function pointer to sectioncheck.
This will be useful when we want to have special handlers which need to go
through more hops to print useful information to the user.

Signed-off-by: Quentin Casasnovas <quentin.casasnovas@oracle.com>
Signed-off-by: Rusty Russell <rusty@rustcorp.com.au>
2015-04-13 21:02:59 +09:30
Quentin Casasnovas 157d1972d0 modpost: add .sched.text and .kprobes.text to the TEXT_SECTIONS list.
sched.text and .kprobes.text should behave exactly like .text with regards
to how we should warn about referencing sections which might get discarded
at runtime.

Signed-off-by: Quentin Casasnovas <quentin.casasnovas@oracle.com>
Signed-off-by: Rusty Russell <rusty@rustcorp.com.au>
2015-04-13 21:02:58 +09:30
Quentin Casasnovas 050e57fd59 modpost: add strict white-listing when referencing sections.
Prints a warning when a section references a section outside a strict
white-list.  This will be useful to print a warning if __ex_table
references a non-executable section.

Signed-off-by: Quentin Casasnovas <quentin.casasnovas@oracle.com>
Signed-off-by: Rusty Russell <rusty@rustcorp.com.au>
2015-04-13 21:02:57 +09:30
Linus Torvalds 6325e940e7 arm64 updates for 3.18:
- eBPF JIT compiler for arm64
 - CPU suspend backend for PSCI (firmware interface) with standard idle
   states defined in DT (generic idle driver to be merged via a different
   tree)
 - Support for CONFIG_DEBUG_SET_MODULE_RONX
 - Support for unmapped cpu-release-addr (outside kernel linear mapping)
 - set_arch_dma_coherent_ops() implemented and bus notifiers removed
 - EFI_STUB improvements when base of DRAM is occupied
 - Typos in KGDB macros
 - Clean-up to (partially) allow kernel building with LLVM
 - Other clean-ups (extern keyword, phys_addr_t usage)
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Merge tag 'arm64-upstream' of git://git.kernel.org/pub/scm/linux/kernel/git/arm64/linux

Pull arm64 updates from Catalin Marinas:
 - eBPF JIT compiler for arm64
 - CPU suspend backend for PSCI (firmware interface) with standard idle
   states defined in DT (generic idle driver to be merged via a
   different tree)
 - Support for CONFIG_DEBUG_SET_MODULE_RONX
 - Support for unmapped cpu-release-addr (outside kernel linear mapping)
 - set_arch_dma_coherent_ops() implemented and bus notifiers removed
 - EFI_STUB improvements when base of DRAM is occupied
 - Typos in KGDB macros
 - Clean-up to (partially) allow kernel building with LLVM
 - Other clean-ups (extern keyword, phys_addr_t usage)

* tag 'arm64-upstream' of git://git.kernel.org/pub/scm/linux/kernel/git/arm64/linux: (51 commits)
  arm64: Remove unneeded extern keyword
  ARM64: make of_device_ids const
  arm64: Use phys_addr_t type for physical address
  aarch64: filter $x from kallsyms
  arm64: Use DMA_ERROR_CODE to denote failed allocation
  arm64: Fix typos in KGDB macros
  arm64: insn: Add return statements after BUG_ON()
  arm64: debug: don't re-enable debug exceptions on return from el1_dbg
  Revert "arm64: dmi: Add SMBIOS/DMI support"
  arm64: Implement set_arch_dma_coherent_ops() to replace bus notifiers
  of: amba: use of_dma_configure for AMBA devices
  arm64: dmi: Add SMBIOS/DMI support
  arm64: Correct ftrace calls to aarch64_insn_gen_branch_imm()
  arm64:mm: initialize max_mapnr using function set_max_mapnr
  setup: Move unmask of async interrupts after possible earlycon setup
  arm64: LLVMLinux: Fix inline arm64 assembly for use with clang
  arm64: pageattr: Correctly adjust unaligned start addresses
  net: bpf: arm64: fix module memory leak when JIT image build fails
  arm64: add PSCI CPU_SUSPEND based cpu_suspend support
  arm64: kernel: introduce cpu_init_idle CPU operation
  ...
2014-10-08 05:34:24 -04:00
Kyle McMartin 6c34f1f542 aarch64: filter $x from kallsyms
Similar to ARM, AArch64 is generating $x and $d syms... which isn't
terribly helpful when looking at %pF output and the like. Filter those
out in kallsyms, modpost and when looking at module symbols.

Seems simplest since none of these check EM_ARM anyway, to just add it
to the strchr used, rather than trying to make things overly
complicated.

initcall_debug improves:
dmesg_before.txt: initcall $x+0x0/0x154 [sg] returned 0 after 26331 usecs
dmesg_after.txt: initcall init_sg+0x0/0x154 [sg] returned 0 after 15461 usecs

Signed-off-by: Kyle McMartin <kyle@redhat.com>
Acked-by: Rusty Russell <rusty@rustcorp.com.au>
Signed-off-by: Catalin Marinas <catalin.marinas@arm.com>
2014-10-02 17:01:51 +01:00
Mathias Krause d93e1719a3 modpost: simplify file name generation of *.mod.c files
Avoid the variable length array (vla), just use PATH_MAX instead.
This not only makes this code clang friedly, it also leads to a
code size reduction:

   text    data     bss     dec     hex filename
  51765    2224   12416   66405   10365 scripts/mod/modpost.old
  51677    2224   12416   66317   1030d scripts/mod/modpost.new

Signed-off-by: Mathias Krause <minipli@googlemail.com>
Signed-off-by: Rusty Russell <rusty@rustcorp.com.au>
2014-08-27 21:54:11 +09:30
Mathias Krause 7a3ee75385 modpost: reduce visibility of symbols and constify r/o arrays
Internally used symbols of modpost don't need to be externally visible;
make them static. Also constify the string arrays so they resist in the
r/o section instead of being runtime writable.

Those changes lead to a small size reduction as can be seen below:

   text    data     bss     dec     hex filename
  51381    2640   12416   66437   10385 scripts/mod/modpost.old
  51765    2224   12416   66405   10365 scripts/mod/modpost.new

Signed-off-by: Mathias Krause <minipli@googlemail.com>
Signed-off-by: Rusty Russell <rusty@rustcorp.com.au>
2014-08-27 21:54:10 +09:30
Rasmus Villemoes a0d8f80374 scripts: modpost: Remove numeric suffix pattern matching
For several years, the pattern "foo$" has effectively been treated as
equivalent to "foo" due to a bug in the (misnamed) helper
number_prefix(). This hasn't been observed to cause any problems, so
remove the broken $ functionality and change all foo$ patterns to foo.

Signed-off-by: Rasmus Villemoes <linux@rasmusvillemoes.dk>
Signed-off-by: Rusty Russell <rusty@rustcorp.com.au>
2014-07-27 20:52:46 +09:30
Michal Nazarewicz fcd38ed0ff scripts: modpost: fix compilation warning
The scripts/mod/modpost.c triggers the following warning:

scripts/mod/modpost.c: In function ‘remove_dot’:
scripts/mod/modpost.c:1710:10: warning: ignoring return value of ‘strtoul’, declared with attribute warn_unused_result [-Wunused-result]

The remove_dot function that calls strtoul does not care about the
numeric value of the string that is parsed but only looks for the
end of the numeric sequence.  As such, it's equivalent to just skip
over all digits.

Signed-off-by: Michal Nazarewicz <mina86@mina86.com>
Signed-off-by: Rusty Russell <rusty@rustcorp.com.au>
2014-07-27 20:52:45 +09:30
Linus Torvalds c1fdb2d338 Merge branch 'misc' of git://git.kernel.org/pub/scm/linux/kernel/git/mmarek/kbuild
Pull kbuild misc updates from Michal Marek:
 "This is the non-critical part of kbuild for v3.16-rc1:
   - make deb-pkg can do s390x and arm64
   - new patterns in scripts/tags.sh
   - scripts/tags.sh skips userspace tools' sources (which sometimes
     have copies of kernel structures) and symlinks
   - improvements to the objdiff tool
   - two new coccinelle patches
   - other minor fixes"

* 'misc' of git://git.kernel.org/pub/scm/linux/kernel/git/mmarek/kbuild:
  scripts: objdiff: support directories for the augument of record command
  scripts: objdiff: fix a comment
  scripts: objdiff: change the extension of disassembly from .o to .dis
  scripts: objdiff: improve path flexibility for record command
  scripts: objdiff: remove unnecessary code
  scripts: objdiff: direct error messages to stderr
  scripts: objdiff: get the path to .tmp_objdiff more simply
  deb-pkg: Add automatic support for s390x architecture
  coccicheck: Add unneeded return variable test
  kbuild: Fix a typo in documentation
  kbuild: trivial - use tabs for code indent where possible
  kbuild: trivial - remove trailing empty lines
  coccinelle: Check for missing NULL terminators in of_device_id tables
  scripts/tags.sh: ignore symlink'ed source files
  scripts/tags.sh: add regular expression replacement pattern for memcg
  builddeb: add arm64 in the supported architectures
  builddeb: use $OBJCOPY variable instead of objcopy
  scripts/tags.sh: ignore code of user space tools
  scripts/tags.sh: add pattern for DEFINE_HASHTABLE
  .gitignore: ignore Module.symvers in all directories
2014-06-12 21:29:20 -07:00
Linus Torvalds 4251c2a670 Most of this is cleaning up various driver sysfs permissions so we can
re-add the perm check (we unified the module param and sysfs checks, but
 the module ones were stronger so we weakened them temporarily).
 
 Param parsing gets documented, and also "--" now forces args to be
 handed to init (and ignored by the kernel).
 
 Module NX/RO protections get tightened: we now set them before calling
 parse_args().
 
 Cheers,
 Rusty.
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Merge tag 'modules-next-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/rusty/linux

Pull module updates from Rusty Russell:
 "Most of this is cleaning up various driver sysfs permissions so we can
  re-add the perm check (we unified the module param and sysfs checks,
  but the module ones were stronger so we weakened them temporarily).

  Param parsing gets documented, and also "--" now forces args to be
  handed to init (and ignored by the kernel).

  Module NX/RO protections get tightened: we now set them before calling
  parse_args()"

* tag 'modules-next-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/rusty/linux:
  module: set nx before marking module MODULE_STATE_COMING.
  samples/kobject/: avoid world-writable sysfs files.
  drivers/hid/hid-picolcd_fb: avoid world-writable sysfs files.
  drivers/staging/speakup/: avoid world-writable sysfs files.
  drivers/regulator/virtual: avoid world-writable sysfs files.
  drivers/scsi/pm8001/pm8001_ctl.c: avoid world-writable sysfs files.
  drivers/hid/hid-lg4ff.c: avoid world-writable sysfs files.
  drivers/video/fbdev/sm501fb.c: avoid world-writable sysfs files.
  drivers/mtd/devices/docg3.c: avoid world-writable sysfs files.
  speakup: fix incorrect perms on speakup_acntsa.c
  cpumask.h: silence warning with -Wsign-compare
  Documentation: Update kernel-parameters.tx
  param: hand arguments after -- straight to init
  modpost: Fix resource leak in read_dump()
2014-06-11 16:09:14 -07:00
Masahiro Yamada bb66fc6719 kbuild: trivial - use tabs for code indent where possible
Signed-off-by: Masahiro Yamada <yamada.m@jp.panasonic.com>
Signed-off-by: Michal Marek <mmarek@suse.cz>
2014-06-10 14:00:53 +02:00
Paul Bolle baec30e419 modpost: Fix comment typo "Modules.symvers"
Signed-off-by: Paul Bolle <pebolle@tiscali.nl>
Signed-off-by: Jiri Kosina <jkosina@suse.cz>
2014-05-05 15:44:11 +02:00
Christian Engelmayer 2ee41e62ba modpost: Fix resource leak in read_dump()
Function read_dump() memory maps the input via grab_file(), but fails to call
the corresponding unmap function. Add the missing call to release_file().
Detected by Coverity: CID 1192419

Signed-off-by: Christian Engelmayer <cengelma@gmx.at>
Signed-off-by: Rusty Russell <rusty@rustcorp.com.au>
2014-04-28 11:48:34 +09:30
Linus Torvalds 176ab02d49 Merge branch 'x86-asmlinkage-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip
Pull x86 LTO changes from Peter Anvin:
 "More infrastructure work in preparation for link-time optimization
  (LTO).  Most of these changes is to make sure symbols accessed from
  assembly code are properly marked as visible so the linker doesn't
  remove them.

  My understanding is that the changes to support LTO are still not
  upstream in binutils, but are on the way there.  This patchset should
  conclude the x86-specific changes, and remaining patches to actually
  enable LTO will be fed through the Kbuild tree (other than keeping up
  with changes to the x86 code base, of course), although not
  necessarily in this merge window"

* 'x86-asmlinkage-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip: (25 commits)
  Kbuild, lto: Handle basic LTO in modpost
  Kbuild, lto: Disable LTO for asm-offsets.c
  Kbuild, lto: Add a gcc-ld script to let run gcc as ld
  Kbuild, lto: add ld-version and ld-ifversion macros
  Kbuild, lto: Drop .number postfixes in modpost
  Kbuild, lto, workaround: Don't warn for initcall_reference in modpost
  lto: Disable LTO for sys_ni
  lto: Handle LTO common symbols in module loader
  lto, workaround: Add workaround for initcall reordering
  lto: Make asmlinkage __visible
  x86, lto: Disable LTO for the x86 VDSO
  initconst, x86: Fix initconst mistake in ts5500 code
  initconst: Fix initconst mistake in dcdbas
  asmlinkage: Make trace_hardirqs_on/off_caller visible
  asmlinkage, x86: Fix 32bit memcpy for LTO
  asmlinkage Make __stack_chk_failed and memcmp visible
  asmlinkage: Mark rwsem functions that can be called from assembler asmlinkage
  asmlinkage: Make main_extable_sort_needed visible
  asmlinkage, mutex: Mark __visible
  asmlinkage: Make trace_hardirq visible
  ...
2014-03-31 14:13:25 -07:00
David A. Long c9698e5cd6 ARM: 7964/1: Detect section mismatches in thumb relocations
Add processing for normally encountered thumb relocation types so that
section mismatches will be detected.

Comment from Rusty Russell follows:

Happiest for this to go through an ARM tree, so:

Signed-off-by: David A. Long <dave.long@linaro.org>
Acked-by: Rusty Russell <rusty@rustcorp.com.au>
Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
2014-02-18 19:42:00 +00:00
Andi Kleen ef178f9238 Kbuild, lto: Handle basic LTO in modpost
- Don't warn about LTO marker symbols. modpost runs before
the linker, so the module is not necessarily LTOed yet.
- Don't complain about .gnu.lto* sections

Signed-off-by: Andi Kleen <ak@linux.intel.com>
Link: http://lkml.kernel.org/r/1391846481-31491-13-git-send-email-ak@linux.intel.com
Signed-off-by: H. Peter Anvin <hpa@linux.intel.com>
2014-02-13 20:25:05 -08:00
Andi Kleen 7d02b490e9 Kbuild, lto: Drop .number postfixes in modpost
LTO turns all global symbols effectively into statics. This
has the side effect that they all have a .NUMBER postfix to make
them unique. In modpost drop this postfix because it confuses
it.

Signed-off-by: Andi Kleen <ak@linux.intel.com>
Link: http://lkml.kernel.org/r/1391846481-31491-8-git-send-email-ak@linux.intel.com
Signed-off-by: H. Peter Anvin <hpa@linux.intel.com>
2014-02-13 20:24:58 -08:00
Andi Kleen 77ab21adae Kbuild, lto, workaround: Don't warn for initcall_reference in modpost
This reference is discarded, but can cause warnings when it refers to
exit. Ignore for now.

This is a workaround and can be removed once we get rid of
-fno-toplevel-reorder

Signed-off-by: Andi Kleen <ak@linux.intel.com>
Link: http://lkml.kernel.org/r/1391846481-31491-7-git-send-email-ak@linux.intel.com
Signed-off-by: H. Peter Anvin <hpa@linux.intel.com>
2014-02-13 20:24:56 -08:00
Andreas Schwab 8fe9c93e74 powerpc: Add vr save/restore functions
GCC 4.8 now generates out-of-line vr save/restore functions when
optimizing for size.  They are needed for the raid6 altivec support.

Signed-off-by: Andreas Schwab <schwab@linux-m68k.org>
Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
2014-01-15 13:46:43 +11:00
Linus Torvalds ce6513f758 Mainly boring here, too. rmmod --wait finally removed, though.
Cheers,
 Rusty.
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Merge tag 'modules-next-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/rusty/linux

Pull module updates from Rusty Russell:
 "Mainly boring here, too.  rmmod --wait finally removed, though"

* tag 'modules-next-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/rusty/linux:
  modpost: fix bogus 'exported twice' warnings.
  init: fix in-place parameter modification regression
  asmlinkage, module: Make ksymtab and kcrctab symbols and __this_module __visible
  kernel: add support for init_array constructors
  modpost: Optionally ignore secondary errors seen if a single module build fails
  module: remove rmmod --wait option.
2013-11-15 13:27:50 +09:00
Andi Kleen b5064654c5 scripts/mod/modpost.c: handle non ABS crc symbols
For some reason I managed to trick gcc into create CRC symbols that are
not absolute anymore, but weak.

Make modpost handle this case.

Signed-off-by: Andi Kleen <ak@linux.intel.com>
Cc: Al Viro <viro@ZenIV.linux.org.uk>
Cc: Geert Uytterhoeven <geert@linux-m68k.org>
Cc: Tetsuo Handa <penguin-kernel@i-love.sakura.ne.jp>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2013-11-13 12:09:12 +09:00
Rusty Russell b6568b1a19 modpost: fix bogus 'exported twice' warnings.
Andi's change in e0f244c63f ("asmlinkage, module: Make ksymtab and
kcrctab symbols and __this_module __visible") make the crc appear
first in the symbol table.

modpost creates an entry when it sees the CRC, then when it sees the
actual symbol, it complains that it's seen it before.  The preloaded
flag already exists for the equivalent case where we loaded from
Module.symvers, so use that.

Reported-by: Stephen Rothwell <sfr@canb.auug.org.au>
Tested-by: The Awesome Power Of linux-next
Signed-off-by: Rusty Russell <rusty@rustcorp.com.au>
2013-11-07 12:11:59 +10:30
Andi Kleen e0f244c63f asmlinkage, module: Make ksymtab and kcrctab symbols and __this_module __visible
Make the ksymtab symbols for EXPORT_SYMBOL visible.
This prevents the LTO compiler from adding a .NUMBER prefix,
which avoids various problems in later export processing.

Cc: rusty@rustcorp.com.au
Signed-off-by: Andi Kleen <ak@linux.intel.com>
Signed-off-by: Rusty Russell <rusty@rustcorp.com.au>
2013-10-29 09:43:37 +10:30
Guenter Roeck eed380f3f5 modpost: Optionally ignore secondary errors seen if a single module build fails
Commit ea4054a23 (modpost: handle huge numbers of modules) added
support for building a large number of modules.

Unfortunately, the commit changed the semantics of the makefile: Instead of
passing only existing object files to modpost, make now passes all expected
object files. If make was started with option -i, this results in a modpost
error if a single file failed to build.

Example with the current btrfs build falure on m68k:

fs/btrfs/btrfs.o: No such file or directory
make[1]: [__modpost] Error 1 (ignored)

This error is followed by lots of errors such as:

m68k-linux-gcc: error: arch/m68k/emu/nfcon.mod.c: No such file or directory
m68k-linux-gcc: fatal error: no input files
compilation terminated.
make[1]: [arch/m68k/emu/nfcon.mod.o] Error 1 (ignored)

This doesn't matter much for normal builds, but it is annoying for builds
started with "make -i" due to the large number of secondary errors.
Those errors unnececessarily clog any error log and make it difficult
to find the real errors in the build.

Fix the problem by adding a new parameter '-n' to modpost. If this parameter
is specified, modpost reports but ignores missing object files.

With this patch, error output from above problem is (with make -i):

m68k-linux-ld: cannot find fs/btrfs/ioctl.o: No such file or directory
make[2]: [fs/btrfs/btrfs.o] Error 1 (ignored)
...
fs/btrfs/btrfs.o: No such file or directory (ignored)

Cc: Rusty Russell <rusty@rustcorp.com.au>
Cc: Michael Marek <mmarek@suse.cz>
Signed-off-by: Guenter Roeck <linux@roeck-us.net>
Signed-off-by: Rusty Russell <rusty@rustcorp.com.au>
2013-09-23 15:45:03 +09:30
Chen Gang 4d10c223ba scripts/mod/modpost.c: permit '.cranges' secton for sh64 architecture.
Need permit '.cranges' section for sh64 architecture, or modpost will
report warning:

    LD      init/built-in.o
  WARNING: init/built-in.o (.cranges): unexpected non-allocatable section.
  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.

Signed-off-by: Chen Gang <gang.chen@asianux.com>
Signed-off-by: Rusty Russell <rusty@rustcorp.com.au>
2013-08-20 15:37:40 +09:30
Linus Torvalds 8dce5f3dee Merge branch 'cpuinit-delete' of git://git.kernel.org/pub/scm/linux/kernel/git/paulg/linux
Pull first stage of __cpuinit removal from Paul Gortmaker:
 "The two commits here 1) dummy out all the __cpuinit macros so that we
  no longer generate such sections, and then 2) remove all the section
  processing that we used to do for those sections.

  This makes all the __cpuinit and friends no-ops, so that we can remove
  the use cases of it at our leisure.  Expect stage 2, which does the
  tree wide removal sweep at the end of the merge window."

* 'cpuinit-delete' of git://git.kernel.org/pub/scm/linux/kernel/git/paulg/linux:
  modpost: remove all traces of cpuinit/cpuexit sections
  init.h: remove __cpuinit sections from the kernel
2013-07-07 11:01:19 -07:00