Commit Graph

13 Commits

Author SHA1 Message Date
Russell King
f5fe12b1ea ARM: spectre-v2: harden user aborts in kernel space
In order to prevent aliasing attacks on the branch predictor,
invalidate the BTB or instruction cache on CPUs that are known to be
affected when taking an abort on a address that is outside of a user
task limit:

Cortex A8, A9, A12, A17, A73, A75: flush BTB.
Cortex A15, Brahma B15: invalidate icache.

If the IBE bit is not set, then there is little point to enabling the
workaround.

Signed-off-by: Russell King <rmk+kernel@armlinux.org.uk>
Boot-tested-by: Tony Lindgren <tony@atomide.com>
Reviewed-by: Tony Lindgren <tony@atomide.com>
2018-05-31 10:40:32 +01:00
Greg Kroah-Hartman
b24413180f License cleanup: add SPDX GPL-2.0 license identifier to files with no license
Many source files in the tree are missing licensing information, which
makes it harder for compliance tools to determine the correct license.

By default all files without license information are under the default
license of the kernel, which is GPL version 2.

Update the files which contain no license information with the 'GPL-2.0'
SPDX license identifier.  The SPDX identifier is a legally binding
shorthand, which can be used instead of the full boiler plate text.

This patch is based on work done by Thomas Gleixner and Kate Stewart and
Philippe Ombredanne.

How this work was done:

Patches were generated and checked against linux-4.14-rc6 for a subset of
the use cases:
 - file had no licensing information it it.
 - file was a */uapi/* one with no licensing information in it,
 - file was a */uapi/* one with existing licensing information,

Further patches will be generated in subsequent months to fix up cases
where non-standard license headers were used, and references to license
had to be inferred by heuristics based on keywords.

The analysis to determine which SPDX License Identifier to be applied to
a file was done in a spreadsheet of side by side results from of the
output of two independent scanners (ScanCode & Windriver) producing SPDX
tag:value files created by Philippe Ombredanne.  Philippe prepared the
base worksheet, and did an initial spot review of a few 1000 files.

The 4.13 kernel was the starting point of the analysis with 60,537 files
assessed.  Kate Stewart did a file by file comparison of the scanner
results in the spreadsheet to determine which SPDX license identifier(s)
to be applied to the file. She confirmed any determination that was not
immediately clear with lawyers working with the Linux Foundation.

Criteria used to select files for SPDX license identifier tagging was:
 - Files considered eligible had to be source code files.
 - Make and config files were included as candidates if they contained >5
   lines of source
 - File already had some variant of a license header in it (even if <5
   lines).

All documentation files were explicitly excluded.

The following heuristics were used to determine which SPDX license
identifiers to apply.

 - when both scanners couldn't find any license traces, file was
   considered to have no license information in it, and the top level
   COPYING file license applied.

   For non */uapi/* files that summary was:

   SPDX license identifier                            # files
   ---------------------------------------------------|-------
   GPL-2.0                                              11139

   and resulted in the first patch in this series.

   If that file was a */uapi/* path one, it was "GPL-2.0 WITH
   Linux-syscall-note" otherwise it was "GPL-2.0".  Results of that was:

   SPDX license identifier                            # files
   ---------------------------------------------------|-------
   GPL-2.0 WITH Linux-syscall-note                        930

   and resulted in the second patch in this series.

 - if a file had some form of licensing information in it, and was one
   of the */uapi/* ones, it was denoted with the Linux-syscall-note if
   any GPL family license was found in the file or had no licensing in
   it (per prior point).  Results summary:

   SPDX license identifier                            # files
   ---------------------------------------------------|------
   GPL-2.0 WITH Linux-syscall-note                       270
   GPL-2.0+ WITH Linux-syscall-note                      169
   ((GPL-2.0 WITH Linux-syscall-note) OR BSD-2-Clause)    21
   ((GPL-2.0 WITH Linux-syscall-note) OR BSD-3-Clause)    17
   LGPL-2.1+ WITH Linux-syscall-note                      15
   GPL-1.0+ WITH Linux-syscall-note                       14
   ((GPL-2.0+ WITH Linux-syscall-note) OR BSD-3-Clause)    5
   LGPL-2.0+ WITH Linux-syscall-note                       4
   LGPL-2.1 WITH Linux-syscall-note                        3
   ((GPL-2.0 WITH Linux-syscall-note) OR MIT)              3
   ((GPL-2.0 WITH Linux-syscall-note) AND MIT)             1

   and that resulted in the third patch in this series.

 - when the two scanners agreed on the detected license(s), that became
   the concluded license(s).

 - when there was disagreement between the two scanners (one detected a
   license but the other didn't, or they both detected different
   licenses) a manual inspection of the file occurred.

 - In most cases a manual inspection of the information in the file
   resulted in a clear resolution of the license that should apply (and
   which scanner probably needed to revisit its heuristics).

 - When it was not immediately clear, the license identifier was
   confirmed with lawyers working with the Linux Foundation.

 - If there was any question as to the appropriate license identifier,
   the file was flagged for further research and to be revisited later
   in time.

In total, over 70 hours of logged manual review was done on the
spreadsheet to determine the SPDX license identifiers to apply to the
source files by Kate, Philippe, Thomas and, in some cases, confirmation
by lawyers working with the Linux Foundation.

Kate also obtained a third independent scan of the 4.13 code base from
FOSSology, and compared selected files where the other two scanners
disagreed against that SPDX file, to see if there was new insights.  The
Windriver scanner is based on an older version of FOSSology in part, so
they are related.

Thomas did random spot checks in about 500 files from the spreadsheets
for the uapi headers and agreed with SPDX license identifier in the
files he inspected. For the non-uapi files Thomas did random spot checks
in about 15000 files.

In initial set of patches against 4.14-rc6, 3 files were found to have
copy/paste license identifier errors, and have been fixed to reflect the
correct identifier.

Additionally Philippe spent 10 hours this week doing a detailed manual
inspection and review of the 12,461 patched files from the initial patch
version early this week with:
 - a full scancode scan run, collecting the matched texts, detected
   license ids and scores
 - reviewing anything where there was a license detected (about 500+
   files) to ensure that the applied SPDX license was correct
 - reviewing anything where there was no detection but the patch license
   was not GPL-2.0 WITH Linux-syscall-note to ensure that the applied
   SPDX license was correct

This produced a worksheet with 20 files needing minor correction.  This
worksheet was then exported into 3 different .csv files for the
different types of files to be modified.

These .csv files were then reviewed by Greg.  Thomas wrote a script to
parse the csv files and add the proper SPDX tag to the file, in the
format that the file expected.  This script was further refined by Greg
based on the output to detect more types of files automatically and to
distinguish between header and source .c files (which need different
comment types.)  Finally Greg ran the script using the .csv files to
generate the patches.

Reviewed-by: Kate Stewart <kstewart@linuxfoundation.org>
Reviewed-by: Philippe Ombredanne <pombredanne@nexb.com>
Reviewed-by: Thomas Gleixner <tglx@linutronix.de>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2017-11-02 11:10:55 +01:00
Vladimir Murzin
4f25463841 ARM: Move system register accessors to asm/cp15.h
Headers linux/irqchip/arm-gic.v3.h and arch/arm/include/asm/kvm_hyp.h
are included in virt/kvm/arm/hyp/vgic-v3-sr.c and both define macros
called __ACCESS_CP15 and __ACCESS_CP15_64 which obviously creates a
conflict. These macros were introduced independently for GIC and KVM
and, in fact, do the same thing.

As an option we could add prefixes to KVM and GIC version of macros so
they won't clash, but it'd introduce code duplication.  Alternatively,
we could keep macro in, say, GIC header and include it in KVM one (or
vice versa), but such dependency would not look nicer.

So we follow arm64 way (it handles this via sysreg.h) and move only
single set of macros to asm/cp15.h

Cc: Russell King <rmk+kernel@armlinux.org.uk>
Acked-by: Marc Zyngier <marc.zyngier@arm.com>
Signed-off-by: Vladimir Murzin <vladimir.murzin@arm.com>
Signed-off-by: Christoffer Dall <christoffer.dall@linaro.org>
2016-09-22 13:22:10 +02:00
Russell King
0aeb3408ca ARM: remove global cr_no_alignment
cr_no_alignment is really only used by the alignment code.  Since we no
longer change the setting of cr_alignment after boot, we can localise
this to alignment.c

Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
2014-06-02 09:20:18 +01:00
Russell King
c6e13600d3 ARM: remove unused adjust_cr() function
adjust_cr() is not used anymore, so let's get rid of it.

Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
2014-06-02 09:20:14 +01:00
Russell King
4585eaff63 ARM: use get_cr() rather than cr_alignment
Rather than reading the cr_alignment variable, use get_cr() to read
directly from the hardware instead.  We have two places where this
occurs, neither of them are performance critical.

Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
2014-05-22 16:27:27 +01:00
Russell King
7668fd577b ARM: make get_cr()/set_cr() use unsigned long values
Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
2014-05-22 16:27:24 +01:00
Linus Torvalds
fb2af0020a Merge branch 'for-linus' of git://git.linaro.org/people/rmk/linux-arm
Pull ARM updates from Russell King:
 "This contains the usual updates from other people (listed below) and
  the usual random muddle of miscellaneous ARM updates which cover some
  low priority bug fixes and performance improvements.

  I've started to put the pull request wording into the merge commits,
  which are:

   - NoMMU stuff:

     This includes the following series sent earlier to the list:
      - nommu-fixes
      - R7 Support
      - MPU support

     I've left out the ARCH_MULTIPLATFORM/!MMU stuff that Arnd and I
     were discussing today until we've reached a conclusion/that's had
     some more review.

     This is rebased (and re-tested) on your devel-stable branch because
     otherwise there were going to be conflicts with Uwe's V7M work now
     that you've merged that.  I've included the fix for limiting MPU to
     CPU_V7.

   - Huge page support

     These changes bring both HugeTLB support and Transparent HugePage
     (THP) support to ARM.  Only long descriptors (LPAE) are supported
     in this series.

     The code has been tested on an Arndale board (Exynos 5250).

   - LPAE updates

     Please pull these miscellaneous LPAE fixes I've been collecting for
     a while now for 3.11.  They've been tested and reviewed by quite a
     few people, and most of the patches are pretty trivial.  -- Will Deacon.

   - arch_timer cleanups

     Please pull these arch_timer cleanups I've been holding onto for a
     while.  They're the same as my last posting, but have been rebased
     to v3.10-rc3.

   - mpidr linearisation (multiprocessor id register - identifies which
     CPU number we are in the system)

     This patch series that implements MPIDR linearization through a
     simple hashing algorithm and updates current cpu_{suspend}/{resume}
     code to use the newly created hash structures to retrieve context
     pointers.  It represents a stepping stone for the implementation of
     power management code on forthcoming multi-cluster ARM systems.

     It has been tested on TC2 (dual cluster A15xA7 system), iMX6q,
     OMAP4 and Tegra, with processors hitting low-power states requiring
     warm-boot resume through the cpu_resume code path"

* 'for-linus' of git://git.linaro.org/people/rmk/linux-arm: (77 commits)
  ARM: 7775/1: mm: Remove do_sect_fault from LPAE code
  ARM: 7777/1: Avoid extra calls to the C compiler
  ARM: 7774/1: Fix dtb dependency to use order-only prerequisites
  ARM: 7770/1: remove residual ARMv2 support from decompressor
  ARM: 7769/1: Cortex-A15: fix erratum 798181 implementation
  ARM: 7768/1: prevent risks of out-of-bound access in ASID allocator
  ARM: 7767/1: let the ASID allocator handle suspended animation
  ARM: 7766/1: versatile: don't mark pen as __INIT
  ARM: 7765/1: perf: Record the user-mode PC in the call chain.
  ARM: 7735/2: Preserve the user r/w register TPIDRURW on context switch and fork
  ARM: kernel: implement stack pointer save array through MPIDR hashing
  ARM: kernel: build MPIDR hash function data structure
  ARM: mpu: Ensure that MPU depends on CPU_V7
  ARM: mpu: protect the vectors page with an MPU region
  ARM: mpu: Allow enabling of the MPU via kconfig
  ARM: 7758/1: introduce config HAS_BANDGAP
  ARM: 7757/1: mm: don't flush icache in switch_mm with hardware broadcasting
  ARM: 7751/1: zImage: don't overwrite ourself with a page table
  ARM: 7749/1: spinlock: retry trylock operation if strex fails on free lock
  ARM: 7748/1: oabi: handle faults when loading swi instruction from userspace
  ...
2013-07-03 09:46:29 -07:00
Jonathan Austin
aca7e5920c ARM: mpu: add PMSA related registers and bitfields to existing headers
This patch adds the following definitions relevant to the PMSA:

Add SCTLR bit 17, (CR_BR - Background Region bit) to the list of CR_*
bitfields. This bit determines whether to use the architecturally defined
memory map

Add the MPUIR to the available registers when using read_cpuid macro. The
MPUIR is the MPU type register.

Signed-off-by: Jonathan Austin <jonathan.austin@arm.com>
Reviewed-by: Will Deacon <will.deacon@arm.com>
CC:"Uwe Kleine-König" <u.kleine-koenig@pengutronix.de>
2013-06-07 17:02:49 +01:00
Rob Herring
bbc8d77db6 ARM: introduce common set_auxcr/get_auxcr functions
Move the private set_auxcr/get_auxcr functions from
drivers/cpuidle/cpuidle-calxeda.c so they can be used across platforms.

Signed-off-by: Rob Herring <rob.herring@calxeda.com>
Cc: Russell King <linux@arm.linux.org.uk>
Signed-off-by: Nicolas Pitre <nico@linaro.org>
Acked-by: Tony Lindgren <tony@atomide.com>
Acked-by: Santosh Shilimkar <santosh.shilimkar@ti.com>
Reviewed-by: Will Deacon <will.deacon@arm.com>
2013-05-29 15:50:34 -04:00
Uwe Kleine-König
b849a60e09 ARM: make cr_alignment read-only #ifndef CONFIG_CPU_CP15
This makes cr_alignment a constant 0 to break code that tries to modify
the value as it's likely that it's built on wrong assumption when
CONFIG_CPU_CP15 isn't defined. For code that is only reading the value 0
is more or less a fine value to report.

Signed-off-by: Uwe Kleine-König <u.kleine-koenig@pengutronix.de>
Message-Id: 1358413196-5609-2-git-send-email-u.kleine-koenig@pengutronix.de (v8)
2013-01-31 21:44:45 +01:00
David Howells
9f97da78bf Disintegrate asm/system.h for ARM
Disintegrate asm/system.h for ARM.

Signed-off-by: David Howells <dhowells@redhat.com>
cc: Russell King <linux@arm.linux.org.uk>
cc: linux-arm-kernel@lists.infradead.org
2012-03-28 18:30:01 +01:00
Russell King
15d07dc9c5 ARM: move CP15 definitions to separate header file
Avoid namespace conflicts with drivers over the CP15 definitions by
moving CP15 related prototypes and definitions to a private header
file.

Acked-by: Stephen Warren <swarren@nvidia.com>
Tested-by: Stephen Warren <swarren@nvidia.com> [Tegra]
Acked-by: H Hartley Sweeten <hsweeten@visionengravers.com>
Tested-by: H Hartley Sweeten <hsweeten@visionengravers.com> [EP93xx]
Acked-by: Nicolas Pitre <nico@linaro.org>
Acked-by: Kukjin Kim <kgene.kim@samsung.com>
Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
Signed-off-by: David Howells <dhowells@redhat.com>
2012-03-28 18:30:01 +01:00