Commit Graph

354 Commits

Author SHA1 Message Date
Linus Torvalds
15ce2658dd Merge tag 'modules-next-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/rusty/linux
Pull module updates from Rusty Russell:
 "Quentin opened a can of worms by adding extable entry checking to
  modpost, but most architectures seem fixed now.  Thanks to all
  involved.

  Last minute rebase because I noticed a "[PATCH]" had snuck into a
  commit message somehow"

* tag 'modules-next-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/rusty/linux:
  modpost: don't emit section mismatch warnings for compiler optimizations
  modpost: expand pattern matching to support substring matches
  modpost: do not try to match the SHT_NUL section.
  modpost: fix extable entry size calculation.
  modpost: fix inverted logic in is_extable_fault_address().
  modpost: handle -ffunction-sections
  modpost: Whitelist .text.fixup and .exception.text
  params: handle quotes properly for values not of form foo="bar".
  modpost: document the use of struct section_check.
  modpost: handle relocations mismatch in __ex_table.
  scripts: add check_extable.sh script.
  modpost: mismatch_handler: retrieve tosym information only when needed.
  modpost: factorize symbol pretty print in get_pretty_name().
  modpost: add handler function pointer to sectioncheck.
  modpost: add .sched.text and .kprobes.text to the TEXT_SECTIONS list.
  modpost: add strict white-listing when referencing sections.
  module: do not print allocation-fail warning on bogus user buffer size
  kernel/module.c: fix typos in message about unused symbols
2015-04-22 09:49:24 -07:00
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
James Hogan
8286ae0330 MIPS: Add CDMM bus support
Add MIPS Common Device Memory Map (CDMM) support in the form of a bus in
the standard Linux device model. Each device attached via CDMM is
discoverable via an 8-bit type identifier and may contain a number of
blocks of memory mapped registers in the CDMM region. IRQs are expected
to be handled separately.

Due to the per-cpu (per-VPE for MT cores) nature of the CDMM devices,
all the driver callbacks take place from workqueues which are run on the
right CPU for the device in question, so that the driver doesn't need to
be as concerned about which CPU it is running on. Callbacks also exist
for when CPUs are taken offline, so that any per-CPU resources used by
the driver can be disabled so they don't get forcefully migrated. CDMM
devices are created as children of the CPU device they are attached to.

Any existing CDMM configuration by the bootloader will be inherited,
however platforms wishing to enable CDMM should implement the weak
mips_cdmm_phys_base() function (see asm/cdmm.h) so that the bus driver
knows where it should put the CDMM region in the physical address space
if the bootloader hasn't already enabled it.

A mips_cdmm_early_probe() function is also provided to allow early boot
or particularly low level code to set up the CDMM region and probe for a
specific device type, for example early console or KGDB IO drivers for
the EJTAG Fast Debug Channel (FDC) CDMM device.

Signed-off-by: James Hogan <james.hogan@imgtec.com>
Cc: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Cc: linux-mips@linux-mips.org
Cc: linux-kernel@vger.kernel.org
Patchwork: https://patchwork.linux-mips.org/patch/9599/
Signed-off-by: Ralf Baechle <ralf@linux-mips.org>
2015-03-31 12:04:12 +02:00
Linus Torvalds
6325e940e7 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 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