linux-stable.git/arch/arm/kernel/vmlinux.lds.S, branch v4.12.2

debug: Fix __bug_table[] in arch linker scripts

2017-04-03T08:22:40+00:00

The kbuild test robot reported this build failure on a number
of architectures:

 >         make.cross ARCH=arm
 >    lib/lib.a(bug.o): In function `find_bug':
 > >> lib/bug.c:135: undefined reference to `__start___bug_table'
 > >> lib/bug.c:135: undefined reference to `__stop___bug_table'

Caused by:

  19d436268dde ("debug: Add _ONCE() logic to report_bug()")

Which moved the BUG_TABLE from RO_DATA_SECTION() to RW_DATA_SECTION(),
but a number of architectures don't use RW_DATA_SECTION(), so they
ended up with no __bug_table[] ...

Ideally all those would use RW_DATA_SECTION() in their linker scripts,
but that's for another day.

Signed-off-by: Peter Zijlstra 
Cc: Linus Torvalds 
Cc: Thomas Gleixner 
Cc: kbuild test robot 
Cc: kbuild-all@01.org
Cc: tipbuild@zytor.com
Link: http://lkml.kernel.org/r/20170330154927.o6qmgfp4bdhrajbm@hirez.programming.kicks-ass.net
Signed-off-by: Ingo Molnar

arch: Rename CONFIG_DEBUG_RODATA and CONFIG_DEBUG_MODULE_RONX

2017-02-07T20:32:52+00:00

Both of these options are poorly named. The features they provide are
necessary for system security and should not be considered debug only.
Change the names to CONFIG_STRICT_KERNEL_RWX and
CONFIG_STRICT_MODULE_RWX to better describe what these options do.

Signed-off-by: Laura Abbott 
Acked-by: Jessica Yu 
Signed-off-by: Kees Cook

nmi_backtrace: generate one-line reports for idle cpus

2016-10-08T01:46:30+00:00

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 
Acked-by: Peter Zijlstra (Intel) 
Tested-by: Peter Zijlstra (Intel) 
Tested-by: Daniel Thompson  [arm]
Tested-by: Petr Mladek 
Cc: Aaron Tomlin 
Cc: Peter Zijlstra (Intel) 
Cc: "Rafael J. Wysocki" 
Cc: Russell King 
Cc: Thomas Gleixner 
Cc: Ingo Molnar 
Signed-off-by: Andrew Morton 
Signed-off-by: Linus Torvalds

arm: jump label may reference text in __exit

2016-08-04T12:50:07+00:00

The jump table can reference text found in an __exit section.  Thus,
instead of discarding it at build time, include EXIT_TEXT as part of
__init and it will be released when the system boots.

Link: http://lkml.kernel.org/r/60284113bb759121e8ae3e99af1535647e52123f.1467837322.git.jbaron@akamai.com
Signed-off-by: Jason Baron 
Cc: Arnd Bergmann 
Cc: "David S. Miller" 
Cc: Benjamin Herrenschmidt 
Cc: Chris Metcalf 
Cc: Heiko Carstens 
Cc: Joe Perches 
Cc: Martin Schwidefsky 
Cc: Michael Ellerman 
Cc: Paul Mackerras 
Cc: Peter Zijlstra 
Signed-off-by: Andrew Morton 
Signed-off-by: Linus Torvalds

ARM: 8583/1: mm: fix location of _etext

2016-07-02T10:01:30+00:00

The _etext position is defined to be the end of the kernel text code,
and should not include any part of the data segments. This interferes
with things that might check memory ranges and expect executable code
up to _etext. Just to be conservative, leave the kernel resource as
it was, using __init_begin instead of _etext as the end mark.

Signed-off-by: Kees Cook 
Signed-off-by: Russell King

arch, ftrace: for KASAN put hard/soft IRQ entries into separate sections

2016-03-25T23:37:42+00:00

KASAN needs to know whether the allocation happens in an IRQ handler.
This lets us strip everything below the IRQ entry point to reduce the
number of unique stack traces needed to be stored.

Move the definition of __irq_entry to  so that the
users don't need to pull in .  Also introduce the
__softirq_entry macro which is similar to __irq_entry, but puts the
corresponding functions to the .softirqentry.text section.

Signed-off-by: Alexander Potapenko 
Acked-by: Steven Rostedt 
Cc: Christoph Lameter 
Cc: Pekka Enberg 
Cc: David Rientjes 
Cc: Joonsoo Kim 
Cc: Andrey Konovalov 
Cc: Dmitry Vyukov 
Cc: Andrey Ryabinin 
Cc: Konstantin Serebryany 
Cc: Dmitry Chernenkov 
Signed-off-by: Andrew Morton 
Signed-off-by: Linus Torvalds

Merge branch 'for-linus' of git://ftp.arm.linux.org.uk/~rmk/linux-arm

2016-03-19T23:31:54+00:00

Pull ARM updates from Russell King:
 "Another mixture of changes this time around:

   - Split XIP linker file from main linker file to make it more
     maintainable, and various XIP fixes, and clean up a resulting
     macro.

   - Decompressor cleanups from Masahiro Yamada

   - Avoid printing an error for a missing L2 cache

   - Remove some duplicated symbols in System.map, and move
     vectors/stubs back into kernel VMA

   - Various low priority fixes from Arnd

   - Updates to allow bus match functions to return negative errno
     values, touching some drivers and the driver core.  Greg has acked
     these changes.

   - Virtualisation platform udpates form Jean-Philippe Brucker.

   - Security enhancements from Kees Cook

   - Rework some Kconfig dependencies and move PSCI idle management code
     out of arch/arm into drivers/firmware/psci.c

   - ARM DMA mapping updates, touching media, acked by Mauro.

   - Fix places in ARM code which should be using virt_to_idmap() so
     that Keystone2 can work.

   - Fix Marvell Tauros2 to work again with non-DT boots.

   - Provide a delay timer for ARM Orion platforms"

* 'for-linus' of git://ftp.arm.linux.org.uk/~rmk/linux-arm: (45 commits)
  ARM: 8546/1: dma-mapping: refactor to fix coherent+cma+gfp=0
  ARM: 8547/1: dma-mapping: store buffer information
  ARM: 8543/1: decompressor: rename suffix_y to compress-y
  ARM: 8542/1: decompressor: merge piggy.*.S and simplify Makefile
  ARM: 8541/1: decompressor: drop redundant FORCE in Makefile
  ARM: 8540/1: decompressor: use clean-files instead of extra-y to clean files
  ARM: 8539/1: decompressor: drop more unneeded assignments to "targets"
  ARM: 8538/1: decompressor: drop unneeded assignments to "targets"
  ARM: 8532/1: uncompress: mark putc as inline
  ARM: 8531/1: turn init_new_context into an inline function
  ARM: 8530/1: remove VIRT_TO_BUS
  ARM: 8537/1: drop unused DEBUG_RODATA from XIP_KERNEL
  ARM: 8536/1: mm: hide __start_rodata_section_aligned for non-debug builds
  ARM: 8535/1: mm: DEBUG_RODATA makes no sense with XIP_KERNEL
  ARM: 8534/1: virt: fix hyp-stub build for pre-ARMv7 CPUs
  ARM: make the physical-relative calculation more obvious
  ARM: 8512/1: proc-v7.S: Adjust stack address when XIP_KERNEL
  ARM: 8411/1: Add default SPARSEMEM settings
  ARM: 8503/1: clk_register_clkdev: remove format string interface
  ARM: 8529/1: remove 'i' and 'zi' targets
  ...

ARM: KVM: Move the HYP code to its own section

2016-02-29T18:34:12+00:00

In order to be able to spread the HYP code into multiple compilation
units, adopt a layout similar to that of arm64:
- the HYP text is emited in its own section (.hyp.text)
- two linker generated symbols are use to identify the boundaries
  of that section

No functionnal change.

Acked-by: Christoffer Dall 
Signed-off-by: Marc Zyngier

ARM: 8536/1: mm: hide __start_rodata_section_aligned for non-debug builds

2016-02-22T11:39:43+00:00

The __start_rodata_section_aligned is only referenced by the
DEBUG_RODATA code, which is only used when the MMU is enabled,
but the definition fails on !MMU builds:

arch/arm/kernel/vmlinux.lds:702: undefined symbol `SECTION_SHIFT' referenced in expression

This hides the symbol whenever DEBUG_RODATA is disabled.

Signed-off-by: Arnd Bergmann 
Fixes: 64ac2e74f0b2 ("ARM: 8502/1: mm: mark section-aligned portion of rodata NX")
Acked-by: Ard Biesheuvel 
Signed-off-by: Russell King

ARM: 8502/1: mm: mark section-aligned portion of rodata NX

2016-02-11T15:44:10+00:00

When rodata is large enough that it crosses a section boundary after the
kernel text, mark the rest NX. This is as close to full NX of rodata as
we can get without splitting page tables or doing section alignment via
CONFIG_DEBUG_ALIGN_RODATA.

When the config is:

 CONFIG_DEBUG_RODATA=y
 # CONFIG_DEBUG_ALIGN_RODATA is not set

Before:

---[ Kernel Mapping ]---
0x80000000-0x80100000           1M     RW NX SHD
0x80100000-0x80a00000           9M     ro x  SHD
0x80a00000-0xa0000000         502M     RW NX SHD

After:

---[ Kernel Mapping ]---
0x80000000-0x80100000           1M     RW NX SHD
0x80100000-0x80700000           6M     ro x  SHD
0x80700000-0x80a00000           3M     ro NX SHD
0x80a00000-0xa0000000         502M     RW NX SHD

Signed-off-by: Kees Cook 
Reviewed-by: Ard Biesheuvel 
Signed-off-by: Russell King