linux-stable.git/arch/arm/include/asm/Kbuild, branch linux-4.9.y Linux kernel stable tree ARM: 8715/1: add a private asm/unaligned.h 2017-11-08T09:08:32+00:00 Arnd Bergmann arnd@arndb.de 2017-10-20T20:17:05+00:00 b3937f55c725894d03ca6592a8dd29662e85251d commit 1cce91dfc8f7990ca3aea896bfb148f240b12860 upstream. The asm-generic/unaligned.h header provides two different implementations for accessing unaligned variables: the access_ok.h version used when CONFIG_HAVE_EFFICIENT_UNALIGNED_ACCESS is set pretends that all pointers are in fact aligned, while the le_struct.h version convinces gcc that the alignment of a pointer is '1', to make it issue the correct load/store instructions depending on the architecture flags. On ARMv5 and older, we always use the second version, to let the compiler use byte accesses. On ARMv6 and newer, we currently use the access_ok.h version, so the compiler can use any instruction including stm/ldm and ldrd/strd that will cause an alignment trap. This trap can significantly impact performance when we have to do a lot of fixups and, worse, has led to crashes in the LZ4 decompressor code that does not have a trap handler. This adds an ARM specific version of asm/unaligned.h that uses the le_struct.h/be_struct.h implementation unconditionally. This should lead to essentially the same code on ARMv6+ as before, with the exception of using regular load/store instructions instead of the trapping instructions multi-register variants. The crash in the LZ4 decompressor code was probably introduced by the patch replacing the LZ4 implementation, commit 4e1a33b105dd ("lib: update LZ4 compressor module"), so linux-4.11 and higher would be affected most. However, we probably want to have this backported to all older stable kernels as well, to help with the performance issues. There are two follow-ups that I think we should also work on, but not backport to stable kernels, first to change the asm-generic version of the header to remove the ARM special case, and second to review all other uses of CONFIG_HAVE_EFFICIENT_UNALIGNED_ACCESS to see if they might be affected by the same problem on ARM. Signed-off-by: Arnd Bergmann <arnd@arndb.de> Signed-off-by: Russell King <rmk+kernel@armlinux.org.uk> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org> 
commit 1cce91dfc8f7990ca3aea896bfb148f240b12860 upstream.

The asm-generic/unaligned.h header provides two different implementations
for accessing unaligned variables: the access_ok.h version used when
CONFIG_HAVE_EFFICIENT_UNALIGNED_ACCESS is set pretends that all pointers
are in fact aligned, while the le_struct.h version convinces gcc that the
alignment of a pointer is '1', to make it issue the correct load/store
instructions depending on the architecture flags.

On ARMv5 and older, we always use the second version, to let the compiler
use byte accesses. On ARMv6 and newer, we currently use the access_ok.h
version, so the compiler can use any instruction including stm/ldm and
ldrd/strd that will cause an alignment trap. This trap can significantly
impact performance when we have to do a lot of fixups and, worse, has
led to crashes in the LZ4 decompressor code that does not have a trap
handler.

This adds an ARM specific version of asm/unaligned.h that uses the
le_struct.h/be_struct.h implementation unconditionally. This should lead
to essentially the same code on ARMv6+ as before, with the exception of
using regular load/store instructions instead of the trapping instructions
multi-register variants.

The crash in the LZ4 decompressor code was probably introduced by the
patch replacing the LZ4 implementation, commit 4e1a33b105dd ("lib: update
LZ4 compressor module"), so linux-4.11 and higher would be affected most.
However, we probably want to have this backported to all older stable
kernels as well, to help with the performance issues.

There are two follow-ups that I think we should also work on, but not
backport to stable kernels, first to change the asm-generic version of
the header to remove the ARM special case, and second to review all
other uses of CONFIG_HAVE_EFFICIENT_UNALIGNED_ACCESS to see if they
might be affected by the same problem on ARM.

Signed-off-by: Arnd Bergmann <arnd@arndb.de>
Signed-off-by: Russell King <rmk+kernel@armlinux.org.uk>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Revert "arm: move exports to definitions" 2016-11-23T10:00:03+00:00 Russell King rmk+kernel@armlinux.org.uk 2016-11-23T10:00:03+00:00 8478132a8784605fe07ede555f7277d989368d73 This reverts commit 4dd1837d7589f468ed109556513f476e7a7f9121. Moving the exports for assembly code into the assembly files breaks KSYM trimming, but also breaks modversions. While fixing the KSYM trimming is trivial, fixing modversions brings us to a technically worse position that we had prior to the above change: - We end up with the prototype definitions divorsed from everything else, which means that adding or removing assembly level ksyms become more fragile: * if adding a new assembly ksyms export, a missed prototype in asm-prototypes.h results in a successful build if no module in the selected configuration makes use of the symbol. * when removing a ksyms export, asm-prototypes.h will get forgotten, with armksyms.c, you'll get a build error if you forget to touch the file. - We end up with the same amount of include files and prototypes, they're just in a header file instead of a .c file with their exports. As for lines of code, we don't get much of a size reduction: (original commit) 47 files changed, 131 insertions(+), 208 deletions(-) (fix for ksyms trimming) 7 files changed, 18 insertions(+), 5 deletions(-) (two fixes for modversions) 1 file changed, 34 insertions(+) 3 files changed, 7 insertions(+), 2 deletions(-) which results in a net total of only 25 lines deleted. As there does not seem to be much benefit from this change of approach, revert the change. Signed-off-by: Russell King <rmk+kernel@armlinux.org.uk> 
This reverts commit 4dd1837d7589f468ed109556513f476e7a7f9121.

Moving the exports for assembly code into the assembly files breaks
KSYM trimming, but also breaks modversions.

While fixing the KSYM trimming is trivial, fixing modversions brings
us to a technically worse position that we had prior to the above
change:

- We end up with the prototype definitions divorsed from everything
  else, which means that adding or removing assembly level ksyms
  become more fragile:
  * if adding a new assembly ksyms export, a missed prototype in
    asm-prototypes.h results in a successful build if no module in
    the selected configuration makes use of the symbol.
  * when removing a ksyms export, asm-prototypes.h will get forgotten,
    with armksyms.c, you'll get a build error if you forget to touch
    the file.

- We end up with the same amount of include files and prototypes,
  they're just in a header file instead of a .c file with their
  exports.

As for lines of code, we don't get much of a size reduction:
 (original commit)
 47 files changed, 131 insertions(+), 208 deletions(-)
 (fix for ksyms trimming)
 7 files changed, 18 insertions(+), 5 deletions(-)
 (two fixes for modversions)
 1 file changed, 34 insertions(+)
 3 files changed, 7 insertions(+), 2 deletions(-)
which results in a net total of only 25 lines deleted.

As there does not seem to be much benefit from this change of approach,
revert the change.

Signed-off-by: Russell King <rmk+kernel@armlinux.org.uk>
arm: move exports to definitions 2016-08-08T03:47:21+00:00 Al Viro viro@zeniv.linux.org.uk 2016-01-13T18:46:22+00:00 4dd1837d7589f468ed109556513f476e7a7f9121 Signed-off-by: Al Viro <viro@zeniv.linux.org.uk> 
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
Merge tag 'armsoc-cleanup' of git://git.kernel.org/pub/scm/linux/kernel/git/arm/arm-soc 2016-03-20T21:37:22+00:00 Linus Torvalds torvalds@linux-foundation.org 2016-03-20T21:37:22+00:00 e88fa1b8b00a947299e2415e819301fa52037cf4 Pull ARM SoC cleanups from Arnd Bergmann: "A few simple cleanups across multiple platforms, not much standing out: - lpc32xx removes its private implementation of the clk API, after generic code was merged in 4.5 - all unused Makefile.boot files get removed - a number of simplifications for shmobile - asm/clkdev.h gets replaced with the asm-generic version after all mach/clkdev.h implementations are gone" * tag 'armsoc-cleanup' of git://git.kernel.org/pub/scm/linux/kernel/git/arm/arm-soc: ARM: shmobile: Kconfig: Get rid of old comment ARM: shmobile: Consolidate SCU mapping code arm: lpc32xx: remove direct control of GPIOs from shared mach file arm: lpc32xx: remove selected HAVE_IDE arm: lpc32xx: switch to common clock framework ARM: Use generic clkdev.h header ARM: plat-versatile: Remove unused clock.c file ARM: netx: remove redundant "depends on ARCH_NETX" ARM: integrator: remove redundant select in Kconfig ARM: drop unused Makefile.boot of Multiplatform SoCs ARM: mvebu: add missing of_node_put() ARM: shmobile: r8a7779: Remove remainings of removed SCU boot setup code ARM: shmobile: Typo s/MIPDR/MPIDR/ ARM: shmobile: Add includes providing forward declarations ARM: shmobile: rcar-gen2: Make rcar_gen2_dma_contiguous static ARM: mv78xx0: use "depends on" instead of "if" after prompt 
Pull ARM SoC cleanups from Arnd Bergmann:
 "A few simple cleanups across multiple platforms, not much standing
  out:

   - lpc32xx removes its private implementation of the clk API, after
     generic code was merged in 4.5
   - all unused Makefile.boot files get removed
   - a number of simplifications for shmobile
   - asm/clkdev.h gets replaced with the asm-generic version after all
     mach/clkdev.h implementations are gone"

* tag 'armsoc-cleanup' of git://git.kernel.org/pub/scm/linux/kernel/git/arm/arm-soc:
  ARM: shmobile: Kconfig: Get rid of old comment
  ARM: shmobile: Consolidate SCU mapping code
  arm: lpc32xx: remove direct control of GPIOs from shared mach file
  arm: lpc32xx: remove selected HAVE_IDE
  arm: lpc32xx: switch to common clock framework
  ARM: Use generic clkdev.h header
  ARM: plat-versatile: Remove unused clock.c file
  ARM: netx: remove redundant "depends on ARCH_NETX"
  ARM: integrator: remove redundant select in Kconfig
  ARM: drop unused Makefile.boot of Multiplatform SoCs
  ARM: mvebu: add missing of_node_put()
  ARM: shmobile: r8a7779: Remove remainings of removed SCU boot setup code
  ARM: shmobile: Typo s/MIPDR/MPIDR/
  ARM: shmobile: Add includes providing forward declarations
  ARM: shmobile: rcar-gen2: Make rcar_gen2_dma_contiguous static
  ARM: mv78xx0: use "depends on" instead of "if" after prompt
ARM: 8518/1: Use correct symbols for XIP_KERNEL 2016-02-11T15:43:14+00:00 Chris Brandt chris.brandt@renesas.com 2016-02-09T18:34:43+00:00 02afa9a87b232bca15bc30808b9310c6388ca1a8 For an XIP build, _etext does not represent the end of the binary image that needs to stay mapped into the MODULES_VADDR area. Years ago, data came before text in the memory map. However, now that the order is text/init/data, an XIP_KERNEL needs to map up to the data location in order to keep from cutting off parts of the kernel that are needed. We only map up to the beginning of data because data has already been copied, so there's no reason to keep it around anymore. A new symbol is created to make it clear what it is we are referring to. This fixes the bug where you might lose the end of your kernel area after page table setup is complete. Signed-off-by: Chris Brandt <chris.brandt@renesas.com> Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk> 
For an XIP build, _etext does not represent the end of the
binary image that needs to stay mapped into the MODULES_VADDR area.
Years ago, data came before text in the memory map. However,
now that the order is text/init/data, an XIP_KERNEL needs to map
up to the data location in order to keep from cutting off
parts of the kernel that are needed.
We only map up to the beginning of data because data has already been
copied, so there's no reason to keep it around anymore.
A new symbol is created to make it clear what it is we are referring
to.

This fixes the bug where you might lose the end of your kernel area
after page table setup is complete.

Signed-off-by: Chris Brandt <chris.brandt@renesas.com>
Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
ARM: Use generic clkdev.h header 2016-02-10T08:22:35+00:00 Stephen Boyd sboyd@codeaurora.org 2016-01-27T22:11:42+00:00 34d2f4d3a4d6a6b204ebfd12d1d2c159360d41a4 Get rid of the clkdev.h file in the ARM port and use the generic one because we've gotten rid of all the machine specific mach/clkdev.h files. Acked-by: Arnd Bergmann <arnd@arndb.de> Signed-off-by: Stephen Boyd <sboyd@codeaurora.org> Signed-off-by: Linus Walleij <linus.walleij@linaro.org> 
Get rid of the clkdev.h file in the ARM port and use the generic
one because we've gotten rid of all the machine specific
mach/clkdev.h files.

Acked-by: Arnd Bergmann <arnd@arndb.de>
Signed-off-by: Stephen Boyd <sboyd@codeaurora.org>
Signed-off-by: Linus Walleij <linus.walleij@linaro.org>
ARM: add support for generic early_ioremap/early_memremap 2015-12-13T18:18:28+00:00 Ard Biesheuvel ard.biesheuvel@linaro.org 2015-09-01T06:59:28+00:00 2937367b8a4b0d46ce3312cb997e4a240b02cf15 This enables the generic early_ioremap implementation for ARM. It uses the fixmap region reserved for kmap. Since early_ioremap is only supported before paging_init(), and kmap is only supported afterwards, this is guaranteed not to cause any clashes. Tested-by: Ryan Harkin <ryan.harkin@linaro.org> Reviewed-by: Matt Fleming <matt@codeblueprint.co.uk> Signed-off-by: Ard Biesheuvel <ard.biesheuvel@linaro.org> 
This enables the generic early_ioremap implementation for ARM.

It uses the fixmap region reserved for kmap. Since early_ioremap
is only supported before paging_init(), and kmap is only supported
afterwards, this is guaranteed not to cause any clashes.

Tested-by: Ryan Harkin <ryan.harkin@linaro.org>
Reviewed-by: Matt Fleming <matt@codeblueprint.co.uk>
Signed-off-by: Ard Biesheuvel <ard.biesheuvel@linaro.org>
ARM: Add msi.h to Kbuild 2015-10-23T18:06:27+00:00 Ley Foon Tan lftan@altera.com 2015-10-23T10:27:10+00:00 0ab089c2548c6a85b86f7d9392b3d53643c6dffd Include asm-generic/msi.h to support CONFIG_GENERIC_MSI_IRQ_DOMAIN. This fixes a compilation error: include/linux/msi.h:123:21: fatal error: asm/msi.h: No such file or directory Signed-off-by: Ley Foon Tan <lftan@altera.com> Signed-off-by: Bjorn Helgaas <bhelgaas@google.com> 
Include asm-generic/msi.h to support CONFIG_GENERIC_MSI_IRQ_DOMAIN.
This fixes a compilation error:

  include/linux/msi.h:123:21: fatal error: asm/msi.h: No such file or directory

Signed-off-by: Ley Foon Tan <lftan@altera.com>
Signed-off-by: Bjorn Helgaas <bhelgaas@google.com>
 Merge branch 'for-linus' of git://ftp.arm.linux.org.uk/~rmk/linux-arm 2015-09-03T23:27:01+00:00 Linus Torvalds torvalds@linux-foundation.org 2015-09-03T23:27:01+00:00 c706c7eb0d08098f0d768aeef945d7cf1f8858b4 Pull ARM development updates from Russell King: "Included in this update: - moving PSCI code from ARM64/ARM to drivers/ - removal of some architecture internals from global kernel view - addition of software based "privileged no access" support using the old domains register to turn off the ability for kernel loads/stores to access userspace. Only the proper accessors will be usable. - addition of early fixup support for early console - re-addition (and reimplementation) of OMAP special interconnect barrier - removal of finish_arch_switch() - only expose cpuX/online in sysfs if hotpluggable - a number of code cleanups" * 'for-linus' of git://ftp.arm.linux.org.uk/~rmk/linux-arm: (41 commits) ARM: software-based priviledged-no-access support ARM: entry: provide uaccess assembly macro hooks ARM: entry: get rid of multiple macro definitions ARM: 8421/1: smp: Collapse arch_cpu_idle_dead() into cpu_die() ARM: uaccess: provide uaccess_save_and_enable() and uaccess_restore() ARM: mm: improve do_ldrd_abort macro ARM: entry: ensure that IRQs are enabled when calling syscall_trace_exit() ARM: entry: efficiency cleanups ARM: entry: get rid of asm_trace_hardirqs_on_cond ARM: uaccess: simplify user access assembly ARM: domains: remove DOMAIN_TABLE ARM: domains: keep vectors in separate domain ARM: domains: get rid of manager mode for user domain ARM: domains: move initial domain setting value to asm/domains.h ARM: domains: provide domain_mask() ARM: domains: switch to keeping domain value in register ARM: 8419/1: dma-mapping: harmonize definition of DMA_ERROR_CODE ARM: 8417/1: refactor bitops functions with BIT_MASK() and BIT_WORD() ARM: 8416/1: Feroceon: use of_iomap() to map register base ARM: 8415/1: early fixmap support for earlycon ... 
Pull ARM development updates from Russell King:
 "Included in this update:

   - moving PSCI code from ARM64/ARM to drivers/

   - removal of some architecture internals from global kernel view

   - addition of software based "privileged no access" support using the
     old domains register to turn off the ability for kernel
     loads/stores to access userspace.  Only the proper accessors will
     be usable.

   - addition of early fixup support for early console

   - re-addition (and reimplementation) of OMAP special interconnect
     barrier

   - removal of finish_arch_switch()

   - only expose cpuX/online in sysfs if hotpluggable

   - a number of code cleanups"

* 'for-linus' of git://ftp.arm.linux.org.uk/~rmk/linux-arm: (41 commits)
  ARM: software-based priviledged-no-access support
  ARM: entry: provide uaccess assembly macro hooks
  ARM: entry: get rid of multiple macro definitions
  ARM: 8421/1: smp: Collapse arch_cpu_idle_dead() into cpu_die()
  ARM: uaccess: provide uaccess_save_and_enable() and uaccess_restore()
  ARM: mm: improve do_ldrd_abort macro
  ARM: entry: ensure that IRQs are enabled when calling syscall_trace_exit()
  ARM: entry: efficiency cleanups
  ARM: entry: get rid of asm_trace_hardirqs_on_cond
  ARM: uaccess: simplify user access assembly
  ARM: domains: remove DOMAIN_TABLE
  ARM: domains: keep vectors in separate domain
  ARM: domains: get rid of manager mode for user domain
  ARM: domains: move initial domain setting value to asm/domains.h
  ARM: domains: provide domain_mask()
  ARM: domains: switch to keeping domain value in register
  ARM: 8419/1: dma-mapping: harmonize definition of DMA_ERROR_CODE
  ARM: 8417/1: refactor bitops functions with BIT_MASK() and BIT_WORD()
  ARM: 8416/1: Feroceon: use of_iomap() to map register base
  ARM: 8415/1: early fixmap support for earlycon
  ...
mm: clean up per architecture MM hook header files 2015-07-17T23:39:53+00:00 Laurent Dufour ldufour@linux.vnet.ibm.com 2015-07-17T23:23:58+00:00 f2abeef9fd6f03ebf417539ed099828a56733098 Commit 2ae416b142b6 ("mm: new mm hook framework") introduced an empty header file (mm-arch-hooks.h) for every architecture, even those which doesn't need to define mm hooks. As suggested by Geert Uytterhoeven, this could be cleaned through the use of a generic header file included via each per architecture asm/include/Kbuild file. The PowerPC architecture is not impacted here since this architecture has to defined the arch_remap MM hook. Signed-off-by: Laurent Dufour <ldufour@linux.vnet.ibm.com> Suggested-by: Geert Uytterhoeven <geert@linux-m68k.org> Acked-by: Geert Uytterhoeven <geert@linux-m68k.org> Acked-by: Vineet Gupta <vgupta@synopsys.com> Cc: Oleg Nesterov <oleg@redhat.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org> 
Commit 2ae416b142b6 ("mm: new mm hook framework") introduced an empty
header file (mm-arch-hooks.h) for every architecture, even those which
doesn't need to define mm hooks.

As suggested by Geert Uytterhoeven, this could be cleaned through the use
of a generic header file included via each per architecture
asm/include/Kbuild file.

The PowerPC architecture is not impacted here since this architecture has
to defined the arch_remap MM hook.

Signed-off-by: Laurent Dufour <ldufour@linux.vnet.ibm.com>
Suggested-by: Geert Uytterhoeven <geert@linux-m68k.org>
Acked-by: Geert Uytterhoeven <geert@linux-m68k.org>
Acked-by: Vineet Gupta <vgupta@synopsys.com>
Cc: Oleg Nesterov <oleg@redhat.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>