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Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
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The 64-bit get_user() wasn't clearing the high word due to a typo in the
error handler. The exception handler entry was already correct, though.
Noticed during recent usercopy test additions in lib/test_user_copy.c.
Signed-off-by: Kees Cook <keescook@chromium.org>
Cc: stable@vger.kernel.org
Signed-off-by: Russell King <rmk+kernel@armlinux.org.uk>
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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>
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Recent kernels have changed their behaviour to be more inconsistent
when handling printk continuations. With todays kernels, the output
looks sane on the console, but dmesg splits individual printk()s which
do not have the KERN_CONT prefix into separate lines.
Since the assembly code is not trivial to add the KERN_CONT, and we
ideally want to avoid using KERN_CONT (as multiple printk()s can race
between different threads), convert the assembly dumping the register
values to C code, and have the C code build the output a line at a
time before dumping to the console.
This avoids the KERN_CONT issue, and also avoids situations where the
output is intermixed with other console activity.
Signed-off-by: Russell King <rmk+kernel@armlinux.org.uk>
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Explain where the value for UDELAY_MULT and UDELAY_SHIFT come from.
Also fix/clarify some comments pertaining to their usage in the
assembly code.
Signed-off-by: Nicolas Pitre <nico@linaro.org>
Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
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git://git.kernel.org/pub/scm/linux/kernel/git/viro/vfs
Pull more misc uaccess and vfs updates from Al Viro:
"The rest of the stuff from -next (more uaccess work) + assorted fixes"
* 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/viro/vfs:
score: traps: Add missing include file to fix build error
fs/super.c: don't fool lockdep in freeze_super() and thaw_super() paths
fs/super.c: fix race between freeze_super() and thaw_super()
overlayfs: Fix setting IOP_XATTR flag
iov_iter: kernel-doc import_iovec() and rw_copy_check_uvector()
blackfin: no access_ok() for __copy_{to,from}_user()
arm64: don't zero in __copy_from_user{,_inatomic}
arm: don't zero in __copy_from_user_inatomic()/__copy_from_user()
arc: don't leak bits of kernel stack into coredump
alpha: get rid of tail-zeroing in __copy_user()
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git://git.kernel.org/pub/scm/linux/kernel/git/mmarek/kbuild
Pull kbuild updates from Michal Marek:
- EXPORT_SYMBOL for asm source by Al Viro.
This does bring a regression, because genksyms no longer generates
checksums for these symbols (CONFIG_MODVERSIONS). Nick Piggin is
working on a patch to fix this.
Plus, we are talking about functions like strcpy(), which rarely
change prototypes.
- Fixes for PPC fallout of the above by Stephen Rothwell and Nick
Piggin
- fixdep speedup by Alexey Dobriyan.
- preparatory work by Nick Piggin to allow architectures to build with
-ffunction-sections, -fdata-sections and --gc-sections
- CONFIG_THIN_ARCHIVES support by Stephen Rothwell
- fix for filenames with colons in the initramfs source by me.
* 'kbuild' of git://git.kernel.org/pub/scm/linux/kernel/git/mmarek/kbuild: (22 commits)
initramfs: Escape colons in depfile
ppc: there is no clear_pages to export
powerpc/64: whitelist unresolved modversions CRCs
kbuild: -ffunction-sections fix for archs with conflicting sections
kbuild: add arch specific post-link Makefile
kbuild: allow archs to select link dead code/data elimination
kbuild: allow architectures to use thin archives instead of ld -r
kbuild: Regenerate genksyms lexer
kbuild: genksyms fix for typeof handling
fixdep: faster CONFIG_ search
ia64: move exports to definitions
sparc32: debride memcpy.S a bit
[sparc] unify 32bit and 64bit string.h
sparc: move exports to definitions
ppc: move exports to definitions
arm: move exports to definitions
s390: move exports to definitions
m68k: move exports to definitions
alpha: move exports to actual definitions
x86: move exports to actual definitions
...
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adjust copy_from_user(), obviously
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
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Guided by grsecurity's analogous __read_only markings in arch/arm,
this applies several uses of __ro_after_init to structures that are
only updated during __init.
Signed-off-by: Kees Cook <keescook@chromium.org>
Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
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Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
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Now that we don't support ARMv3 anymore, the loop based delay code can
convert microsecs into number of loops using a 64-bit multiplication
and more precision.
This allows us to lift the hard limit of 3355 on the bogomips value as
loops_per_jiffy may now safely span the full 32-bit range.
Signed-off-by: Nicolas Pitre <nico@linaro.org>
Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
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With new refcounting we don't need to mark PMDs splitting. Let's drop
code to handle this.
pmdp_splitting_flush() is not needed too: on splitting PMD we will do
pmdp_clear_flush() + set_pte_at(). pmdp_clear_flush() will do IPI as
needed for fast_gup.
[arnd@arndb.de: fix unterminated ifdef in header file]
Signed-off-by: Kirill A. Shutemov <kirill.shutemov@linux.intel.com>
Cc: Sasha Levin <sasha.levin@oracle.com>
Cc: Aneesh Kumar K.V <aneesh.kumar@linux.vnet.ibm.com>
Cc: Jerome Marchand <jmarchan@redhat.com>
Cc: Vlastimil Babka <vbabka@suse.cz>
Cc: Andrea Arcangeli <aarcange@redhat.com>
Cc: Hugh Dickins <hughd@google.com>
Cc: Dave Hansen <dave.hansen@intel.com>
Cc: Mel Gorman <mgorman@suse.de>
Cc: Rik van Riel <riel@redhat.com>
Cc: Vlastimil Babka <vbabka@suse.cz>
Cc: Steve Capper <steve.capper@linaro.org>
Cc: Johannes Weiner <hannes@cmpxchg.org>
Cc: Michal Hocko <mhocko@suse.cz>
Cc: Christoph Lameter <cl@linux.com>
Cc: David Rientjes <rientjes@google.com>
Signed-off-by: Arnd Bergmann <arnd@arndb.de>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
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The ARM compiler inserts calls to __aeabi_idiv() and
__aeabi_uidiv() when it needs to perform division on signed and
unsigned integers. If a processor has support for the sdiv and
udiv instructions, the kernel may overwrite the beginning of those
functions with those instructions and a "bx lr" to get better
performance.
To ensure that those functions are aligned to a 32-bit word for easier
patching (which might not always be the case in Thumb mode) and that
the two patched instructions end up in the same cache line, a 8-byte
alignment is enforced when ARM_PATCH_IDIV is selected.
This was heavily inspired by a previous patch from Stephen Boyd.
Signed-off-by: Nicolas Pitre <nico@linaro.org>
Acked-by: Arnd Bergmann <arnd@arndb.de>
Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
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The uaccess_with_memcpy() code is currently incompatible with the SW
PAN code: it takes locks within the region that we've changed the DACR,
potentially sleeping as a result. As we do not save and restore the
DACR across co-operative sleep events, can lead to an incorrect DACR
value later in this code path.
Reported-by: Peter Rosin <peda@axentia.se>
Tested-by: Peter Rosin <peda@axentia.se>
Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
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Add unwinding annotations so that unwinding from this function
works properly.
Signed-off-by: Stephen Boyd <sboyd@codeaurora.org>
Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
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for-linus
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Provide a software-based implementation of the priviledged no access
support found in ARMv8.1.
Userspace pages are mapped using a different domain number from the
kernel and IO mappings. If we switch the user domain to "no access"
when we enter the kernel, we can prevent the kernel from touching
userspace.
However, the kernel needs to be able to access userspace via the
various user accessor functions. With the wrapping in the previous
patch, we can temporarily enable access when the kernel needs user
access, and re-disable it afterwards.
This allows us to trap non-intended accesses to userspace, eg, caused
by an inadvertent dereference of the LIST_POISON* values, which, with
appropriate user mappings setup, can be made to succeed. This in turn
can allow use-after-free bugs to be further exploited than would
otherwise be possible.
Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
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Provide uaccess_save_and_enable() and uaccess_restore() to permit
control of userspace visibility to the kernel, and hook these into
the appropriate places in the kernel where we need to access
userspace.
Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
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The mmap semaphore should not be taken when page faults are disabled.
Since pagefault_disable() no longer disables preemption, we now need
to use faulthandler_disabled() in place of in_atomic().
Signed-off-by: Nicolas Pitre <nico@linaro.org>
Tested-by: Mark Salter <msalter@redhat.com>
Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
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We don't want GCC optimising our memset_io(), memcpy_fromio() or
memcpy_toio() variants, so we must not call one of the standard
functions. Provide a separate name for our assembly memcpy() and
memset() functions, and use that instead, thereby bypassing GCC's
ability to optimise these operations.
GCCs optimisation may introduce unaligned accesses which are invalid
for device mappings.
Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
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Pull ARM updates from Russell King:
"Bigger items included in this update are:
- A series of updates from Arnd for ARM randconfig build failures
- Updates from Dmitry for StrongARM SA-1100 to move IRQ handling to
drivers/irqchip/
- Move ARMs SP804 timer to drivers/clocksource/
- Perf updates from Mark Rutland in preparation to move the ARM perf
code into drivers/ so it can be shared with ARM64.
- MCPM updates from Nicolas
- Add support for taking platform serial number from DT
- Re-implement Keystone2 physical address space switch to conform to
architecture requirements
- Clean up ARMv7 LPAE code, which goes in hand with the Keystone2
changes.
- L2C cleanups to avoid unlocking caches if we're prevented by the
secure support to unlock.
- Avoid cleaning a potentially dirty cache containing stale data on
CPU initialisation
- Add ARM-only entry point for secondary startup (for machines that
can only call into a Thumb kernel in ARM mode). Same thing is also
done for the resume entry point.
- Provide arch_irqs_disabled via asm-generic
- Enlarge ARMv7M vector table
- Always use BFD linker for VDSO, as gold doesn't accept some of the
options we need.
- Fix an incorrect BSYM (for Thumb symbols) usage, and convert all
BSYM compiler macros to a "badr" (for branch address).
- Shut up compiler warnings provoked by our cmpxchg() implementation.
- Ensure bad xchg sizes fail to link"
* 'for-linus' of git://ftp.arm.linux.org.uk/~rmk/linux-arm: (75 commits)
ARM: Fix build if CLKDEV_LOOKUP is not configured
ARM: fix new BSYM() usage introduced via for-arm-soc branch
ARM: 8383/1: nommu: avoid deprecated source register on mov
ARM: 8391/1: l2c: add options to overwrite prefetching behavior
ARM: 8390/1: irqflags: Get arch_irqs_disabled from asm-generic
ARM: 8387/1: arm/mm/dma-mapping.c: Add arm_coherent_dma_mmap
ARM: 8388/1: tcm: Don't crash when TCM banks are protected by TrustZone
ARM: 8384/1: VDSO: force use of BFD linker
ARM: 8385/1: VDSO: group link options
ARM: cmpxchg: avoid warnings from macro-ized cmpxchg() implementations
ARM: remove __bad_xchg definition
ARM: 8369/1: ARMv7M: define size of vector table for Vybrid
ARM: 8382/1: clocksource: make ARM_TIMER_SP804 depend on GENERIC_SCHED_CLOCK
ARM: 8366/1: move Dual-Timer SP804 driver to drivers/clocksource
ARM: 8365/1: introduce sp804_timer_disable and remove arm_timer.h inclusion
ARM: 8364/1: fix BE32 module loading
ARM: 8360/1: add secondary_startup_arm prototype in header file
ARM: 8359/1: correct secondary_startup_arm mode
ARM: proc-v7: sanitise and document registers around errata
ARM: proc-v7: clean up MIDR access
...
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git://git.kernel.org/pub/scm/linux/kernel/git/jikos/trivial
Pull trivial tree updates from Jiri Kosina:
"As usual, mostly comment, kerneldoc and printk() fixes"
* 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/jikos/trivial:
lpfc: Grammar s/an negative/a negative/
ARM: lib/lib1funcs.S: fix typo s/substractions/subtractions/
cx25821: cx25821-medusa-reg.h: fix 0x0x prefix
lib: crc-itu-t.[ch] fix 0x0x prefix in integer constants
rapidio: Fix kerneldoc and comment
qla4xxx: Fix printk() in qla4_83xx_read_reset_template() and qla4_83xx_pre_loopback_config()
treewide: Kconfig: fix wording / spelling
usb/serial: fix grammar in Kconfig help text for FTDI_SIO
megaraid_sas: fix kerneldoc
netfilter: ebtables: fix comment grammar
drm/radeon: fix comment
isdn: fix grammar in comment
ARM: KVM: fix comment
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Signed-off-by: Antonio Ospite <ao2@ao2.it>
Cc: Russell King <linux@arm.linux.org.uk>
Cc: Christoffer Dall <christoffer.dall@linaro.org>
Cc: linux-arm-kernel@lists.infradead.org
Acked-by: Russell King <rmk+kernel@arm.linux.org.uk>
Signed-off-by: Jiri Kosina <jkosina@suse.cz>
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BSYM() was invented to allow us to work around a problem with the
assembler, where local symbols resolved by the assembler for the 'adr'
instruction did not take account of their ISA.
Since we don't want BSYM() used elsewhere, replace BSYM() with a new
macro 'badr', which is like the 'adr' pseudo-op, but with the BSYM()
mechanics integrated into it. This ensures that the BSYM()-ification
is only used in conjunction with 'adr'.
Acked-by: Dave Martin <Dave.Martin@arm.com>
Acked-by: Nicolas Pitre <nico@linaro.org>
Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
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We have recently had an example of someone wanting to use a 90kHz timer
for the software delay loop.
udelay() needs to have at least microsecond resolution to allow drivers
access to a delay mechanism with a reasonable chance of delaying the
period they requested within at least a 50% marging of error, especially
for small delays.
Discussion about the udelay() accuracy can be found at:
https://lkml.org/lkml/2011/1/9/37
Reject timers which are unable to supply this level of resolution.
Acked-by: Nicolas Pitre <nico@linaro.org>
Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
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This moves all fixup snippets to the .text.fixup section, which is
a special section that gets emitted along with the .text section
for each input object file, i.e., the snippets are kept much closer
to the code they refer to, which helps prevent linker failure on
large kernels.
Acked-by: Nicolas Pitre <nico@linaro.org>
Signed-off-by: Ard Biesheuvel <ard.biesheuvel@linaro.org>
Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
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This code was restored with commit 080fc66fb5 ("ARM: Bring back ARMv3 IO
and user access code") because the RiscPC memory bus does not understand
half-word load/stores. However only the IO code needed restoring since
the alternative user access code contains no half-word accesses, is
already used when CONFIG_PREEMPT is set and runs faster on a StrongARM.
Signed-off-by: Nicolas Pitre <nico@linaro.org>
Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
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The memory copy functions(memcpy, __copy_from_user, __copy_to_user)
never had unwinding annotations added. Currently, when accessing
invalid pointer by these functions occurs the backtrace shown will
stop at these functions or some completely unrelated function.
Add unwinding annotations in hopes of getting a more useful backtrace
in following cases:
1. die on accessing invalid pointer by these functions
2. kprobe trapped at any instruction within these functions
3. interrupted at any instruction within these functions
Signed-off-by: Lin Yongting <linyongting@gmail.com>
Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
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The memmove function never had unwinding annotations added.
Currently, when accessing invalid pointer by memmove occurs the
backtrace shown will stop at memmove or some completely unrelated
function. Add unwinding annotations in hopes of getting a more
useful backtrace in following cases:
1. die on accessing invalid pointer by memmove
2. kprobe trapped at any instruction within memmove
3. interrupted at any instruction within memmove
Signed-off-by: Lin Yongting <linyongting@gmail.com>
Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
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The __memzero function never had unwinding annotations added.
Currently, when accessing invalid pointer by __memzero occurs the
backtrace shown will stop at __memzero or some completely unrelated
function. Add unwinding annotations in hopes of getting a more
useful backtrace in following cases:
1. die on accessing invalid pointer by __memzero
2. kprobe trapped at any instruction within __memzero
3. interrupted at any instruction within __memzero
Signed-off-by: Lin Yongting <linyongting@gmail.com>
Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
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The memset function never had unwinding annotations added.
Currently, when accessing NULL pointer by memset occurs the
backtrace shown will stop at memset or some completely unrelated
function. Add unwinding annotations in hopes of getting a more
useful backtrace when accessing NULL pointer by memset, kprobe
or interrupt.
Signed-off-by: Lin Yongting <linyongting@gmail.com>
Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
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e38361d 'ARM: 8091/2: add get_user() support for 8 byte types' commit
broke V7 BE get_user call when target var size is 64 bit, but '*ptr' size
is 32 bit or smaller. e38361d changed type of __r2 from 'register
unsigned long' to 'register typeof(x) __r2 asm("r2")' i.e before the change
even when target variable size was 64 bit, __r2 was still 32 bit.
But after e38361d commit, for target var of 64 bit size, __r2 became 64
bit and now it should occupy 2 registers r2, and r3. The issue in BE case
that r3 register is least significant word of __r2 and r2 register is most
significant word of __r2. But __get_user_4 still copies result into r2 (most
significant word of __r2). Subsequent code copies from __r2 into x, but
for situation described it will pick up only garbage from r3 register.
Special __get_user_64t_(124) functions are introduced. They are similar to
corresponding __get_user_(124) function but result stored in r3 register
(lsw in case of 64 bit __r2 in BE image). Those function are used by
get_user macro in case of BE and target var size is 64bit.
Also changed __get_user_lo8 name into __get_user_32t_8 to get consistent
naming accross all cases.
Signed-off-by: Victor Kamensky <victor.kamensky@linaro.org>
Suggested-by: Daniel Thompson <daniel.thompson@linaro.org>
Reviewed-by: Daniel Thompson <daniel.thompson@linaro.org>
Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
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git://git.kernel.org/pub/scm/linux/kernel/git/arm/arm-soc
Pull ARM SoC platform changes from Olof Johansson:
"This is the bulk of new SoC enablement and other platform changes for
3.17:
- Samsung S5PV210 has been converted to DT and multiplatform
- Clock drivers and bindings for some of the lower-end i.MX 1/2
platforms
- Kirkwood, one of the popular Marvell platforms, is folded into the
mvebu platform code, removing mach-kirkwood
- Hwmod data for TI AM43xx and DRA7 platforms
- More additions of Renesas shmobile platform support
- Removal of plat-samsung contents that can be removed with S5PV210
being multiplatform/DT-enabled and the other two old platforms
being removed
New platforms (most with only basic support right now):
- Hisilicon X5HD2 settop box chipset is introduced
- Mediatek MT6589 (mobile chipset) is introduced
- Broadcom BCM7xxx settop box chipset is introduced
+ as usual a lot other pieces all over the platform code"
* tag 'soc-for-3.17' of git://git.kernel.org/pub/scm/linux/kernel/git/arm/arm-soc: (240 commits)
ARM: hisi: remove smp from machine descriptor
power: reset: move hisilicon reboot code
ARM: dts: Add hix5hd2-dkb dts file.
ARM: debug: Rename Hi3716 to HIX5HD2
ARM: hisi: enable hix5hd2 SoC
ARM: hisi: add ARCH_HISI
MAINTAINERS: add entry for Broadcom ARM STB architecture
ARM: brcmstb: select GISB arbiter and interrupt drivers
ARM: brcmstb: add infrastructure for ARM-based Broadcom STB SoCs
ARM: configs: enable SMP in bcm_defconfig
ARM: add SMP support for Broadcom mobile SoCs
Documentation: arm: misc updates to Marvell EBU SoC status
Documentation: arm: add URLs to public datasheets for the Marvell Armada XP SoC
ARM: mvebu: fix build without platforms selected
ARM: mvebu: add cpuidle support for Armada 38x
ARM: mvebu: add cpuidle support for Armada 370
cpuidle: mvebu: add Armada 38x support
cpuidle: mvebu: add Armada 370 support
cpuidle: mvebu: rename the driver from armada-370-xp to mvebu-v7
ARM: mvebu: export the SCU address
...
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Recent contributions, including to DRM and binder, introduce 64-bit
values in their interfaces. A common motivation for this is to allow
the same ABI for 32- and 64-bit userspaces (and therefore also a shared
ABI for 32/64 hybrid userspaces). Anyhow, the developers would like to
avoid gotchas like having to use copy_from_user().
This feature is already implemented on x86-32 and the majority of other
32-bit architectures. The current list of get_user_8 hold out
architectures are: arm, avr32, blackfin, m32r, metag, microblaze,
mn10300, sh.
Credit:
My name sits rather uneasily at the top of this patch. The v1 and
v2 versions of the patch were written by Rob Clark and to produce v4
I mostly copied code from Russell King and H. Peter Anvin. However I
have mangled the patch sufficiently that *blame* is rightfully mine
even if credit should more widely shared.
Changelog:
v5: updated to use the ret macro (requested by Russell King)
v4: remove an inlined add on big endian systems (spotted by Russell King),
used __ARMEB__ rather than BIG_ENDIAN (to match rest of file),
cleared r3 on EFAULT during __get_user_8.
v3: fix a couple of checkpatch issues
v2: pass correct size to check_uaccess, and better handling of narrowing
double word read with __get_user_xb() (Russell King's suggestion)
v1: original
Signed-off-by: Rob Clark <robdclark@gmail.com>
Signed-off-by: Daniel Thompson <daniel.thompson@linaro.org>
Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
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ARMv6 and greater introduced a new instruction ("bx") which can be used
to return from function calls. Recent CPUs perform better when the
"bx lr" instruction is used rather than the "mov pc, lr" instruction,
and this sequence is strongly recommended to be used by the ARM
architecture manual (section A.4.1.1).
We provide a new macro "ret" with all its variants for the condition
code which will resolve to the appropriate instruction.
Rather than doing this piecemeal, and miss some instances, change all
the "mov pc" instances to use the new macro, with the exception of
the "movs" instruction and the kprobes code. This allows us to detect
the "mov pc, lr" case and fix it up - and also gives us the possibility
of deploying this for other registers depending on the CPU selection.
Reported-by: Will Deacon <will.deacon@arm.com>
Tested-by: Stephen Warren <swarren@nvidia.com> # Tegra Jetson TK1
Tested-by: Robert Jarzmik <robert.jarzmik@free.fr> # mioa701_bootresume.S
Tested-by: Andrew Lunn <andrew@lunn.ch> # Kirkwood
Tested-by: Shawn Guo <shawn.guo@freescale.com>
Tested-by: Tony Lindgren <tony@atomide.com> # OMAPs
Tested-by: Gregory CLEMENT <gregory.clement@free-electrons.com> # Armada XP, 375, 385
Acked-by: Sekhar Nori <nsekhar@ti.com> # DaVinci
Acked-by: Christoffer Dall <christoffer.dall@linaro.org> # kvm/hyp
Acked-by: Haojian Zhuang <haojian.zhuang@gmail.com> # PXA3xx
Acked-by: Stefano Stabellini <stefano.stabellini@eu.citrix.com> # Xen
Tested-by: Uwe Kleine-König <u.kleine-koenig@pengutronix.de> # ARMv7M
Tested-by: Simon Horman <horms+renesas@verge.net.au> # Shmobile
Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
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In case there are several possible delay timers, choose the one with the
highest resolution. This code relies on the fact secondary CPUs have not yet
been brought online when register_current_timer_delay() is called. This is
ensured by implementing calibration_delay_done(),
Signed-off-by: Peter De Schrijver <pdeschrijver@nvidia.com>
Acked-by: Russell King <rmk+kernel@arm.linux.org.uk>
Signed-off-by: Stephen Warren <swarren@nvidia.com>
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Renames logical shift macros, 'push' and 'pull', defined in
arch/arm/include/asm/assembler.h, into 'lspush' and 'lspull'.
That eliminates name conflict between 'push' logical shift macro
and 'push' instruction mnemonic. That allows assembler.h to be
included in .S files that use 'push' instruction.
Suggested-by: Will Deacon <will.deacon@arm.com>
Signed-off-by: Victor Kamensky <victor.kamensky@linaro.org>
Acked-by: Nicolas Pitre <nico@linaro.org>
Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
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After a bunch of benchmarking on the interaction between dmb and pldw,
it turns out that issuing the pldw *after* the dmb instruction can
give modest performance gains (~3% atomic_add_return improvement on a
dual A15).
This patch adds prefetchw invocations to our barriered atomic operations
including cmpxchg, test_and_xxx and futexes.
Signed-off-by: Will Deacon <will.deacon@arm.com>
Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
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Enable the compiler intrinsic for byte swapping on arch ARM. This
allows the compiler to detect and be able to optimize out byte
swappings, and has a very modest benefit on vmlinux size (Linaro gcc
4.8):
text data bss dec hex filename
2840310 123932 61960 3026202 2e2d1a vmlinux-lart #orig
2840152 123932 61960 3026044 2e2c7c vmlinux-lart #builtin-bswap
6473120 314840 5616016 12403976 bd4508 vmlinux-mxs #orig
6472586 314848 5616016 12403450 bd42fa vmlinux-mxs #builtin-bswap
7419872 318372 379556 8117800 7bde28 vmlinux-imx_v6_v7 #orig
7419170 318364 379556 8117090 7bdb62 vmlinux-imx_v6_v7 #builtin-bswap
Signed-off-by: Kim Phillips <kim.phillips@freescale.com>
Reviewed-by: Nicolas Pitre <nico@linaro.org>
Acked-by: David Woodhouse <David.Woodhouse@intel.com>
Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
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We don't need the offset for the first function name in each backtrace
entry; this needlessly consumes screen space. This is virtually always
the first or second instruction in the called function.
Also, recognise stmfd instructions which include r10 as a valid stack
saving instruction, and when dumping the registers, dump six registers
per line rather than five, and fix the wrapping.
Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
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Currently mx53 (CortexA8) running at 1GHz reports:
Calibrating delay loop... 663.55 BogoMIPS (lpj=3317760)
Tom Evans verified that alignments of 0x0 and 0x8 run the two instructions of __loop_delay in one clock cycle (1 clock/loop), while alignments of 0x4 and 0xc take 3 clocks to run the loop twice. (1.5 clock/loop)
The original object code looks like this:
00000010 <__loop_const_udelay>:
10: e3e01000 mvn r1, #0
14: e51f201c ldr r2, [pc, #-28] ; 0 <__loop_udelay-0x8>
18: e5922000 ldr r2, [r2]
1c: e0800921 add r0, r0, r1, lsr #18
20: e1a00720 lsr r0, r0, #14
24: e0822b21 add r2, r2, r1, lsr #22
28: e1a02522 lsr r2, r2, #10
2c: e0000092 mul r0, r2, r0
30: e0800d21 add r0, r0, r1, lsr #26
34: e1b00320 lsrs r0, r0, #6
38: 01a0f00e moveq pc, lr
0000003c <__loop_delay>:
3c: e2500001 subs r0, r0, #1
40: 8afffffe bhi 3c <__loop_delay>
44: e1a0f00e mov pc, lr
After adding the 'align 3' directive to __loop_delay (align to 8 bytes):
00000010 <__loop_const_udelay>:
10: e3e01000 mvn r1, #0
14: e51f201c ldr r2, [pc, #-28] ; 0 <__loop_udelay-0x8>
18: e5922000 ldr r2, [r2]
1c: e0800921 add r0, r0, r1, lsr #18
20: e1a00720 lsr r0, r0, #14
24: e0822b21 add r2, r2, r1, lsr #22
28: e1a02522 lsr r2, r2, #10
2c: e0000092 mul r0, r2, r0
30: e0800d21 add r0, r0, r1, lsr #26
34: e1b00320 lsrs r0, r0, #6
38: 01a0f00e moveq pc, lr
3c: e320f000 nop {0}
00000040 <__loop_delay>:
40: e2500001 subs r0, r0, #1
44: 8afffffe bhi 40 <__loop_delay>
48: e1a0f00e mov pc, lr
4c: e320f000 nop {0}
, which now reports:
Calibrating delay loop... 996.14 BogoMIPS (lpj=4980736)
Some more test results:
On mx31 (ARM1136) running at 532 MHz, before the patch:
Calibrating delay loop... 351.43 BogoMIPS (lpj=1757184)
On mx31 (ARM1136) running at 532 MHz after the patch:
Calibrating delay loop... 528.79 BogoMIPS (lpj=2643968)
Also tested on mx6 (CortexA9) and on mx27 (ARM926), which shows the same
BogoMIPS value before and after this patch.
Reported-by: Tom Evans <tom_usenet@optusnet.com.au>
Suggested-by: Tom Evans <tom_usenet@optusnet.com.au>
Signed-off-by: Fabio Estevam <fabio.estevam@freescale.com>
Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
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Uwe reported a build failure when targetting a NOMMU platform with my
recent prefetch changes:
arch/arm/lib/changebit.S: Assembler messages:
arch/arm/lib/changebit.S:15: Error: architectural extension `mp' is
not allowed for the current base architecture
This is due to use of the .arch_extension mp directive immediately prior
to an ALT_SMP(...) instruction. Whilst the ALT_SMP macro will expand to
nothing if !CONFIG_SMP, gas will still choke on the directive.
This patch fixes the issue by only emitting the sequence (including the
directive) if CONFIG_SMP=y.
Tested-by: Uwe Kleine-König <u.kleine-koenig@pengutronix.de>
Signed-off-by: Will Deacon <will.deacon@arm.com>
Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
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Pull ARM updates from Russell King:
"Included in this series are:
1. BE8 (modern big endian) changes for ARM from Ben Dooks
2. big.Little support from Nicolas Pitre and Dave Martin
3. support for LPAE systems with all system memory above 4GB
4. Perf updates from Will Deacon
5. Additional prefetching and other performance improvements from Will.
6. Neon-optimised AES implementation fro Ard.
7. A number of smaller fixes scattered around the place.
There is a rather horrid merge conflict in tools/perf - I was never
notified of the conflict because it originally occurred between Will's
tree and other stuff. Consequently I have a resolution which Will
forwarded me, which I'll forward on immediately after sending this
mail.
The other notable thing is I'm expecting some build breakage in the
crypto stuff on ARM only with Ard's AES patches. These were merged
into a stable git branch which others had already pulled, so there's
little I can do about this. The problem is caused because these
patches have a dependency on some code in the crypto git tree - I
tried requesting a branch I can pull to resolve these, and all I got
each time from the crypto people was "we'll revert our patches then"
which would only make things worse since I still don't have the
dependent patches. I've no idea what's going on there or how to
resolve that, and since I can't split these patches from the rest of
this pull request, I'm rather stuck with pushing this as-is or
reverting Ard's patches.
Since it should "come out in the wash" I've left them in - the only
build problems they seem to cause at the moment are with randconfigs,
and since it's a new feature anyway. However, if by -rc1 the
dependencies aren't in, I think it'd be best to revert Ard's patches"
I resolved the perf conflict roughly as per the patch sent by Russell,
but there may be some differences. Any errors are likely mine. Let's
see how the crypto issues work out..
* 'for-linus' of git://git.linaro.org/people/rmk/linux-arm: (110 commits)
ARM: 7868/1: arm/arm64: remove atomic_clear_mask() in "include/asm/atomic.h"
ARM: 7867/1: include: asm: use 'int' instead of 'unsigned long' for 'oldval' in atomic_cmpxchg().
ARM: 7866/1: include: asm: use 'long long' instead of 'u64' within atomic.h
ARM: 7871/1: amba: Extend number of IRQS
ARM: 7887/1: Don't smp_cross_call() on UP devices in arch_irq_work_raise()
ARM: 7872/1: Support arch_irq_work_raise() via self IPIs
ARM: 7880/1: Clear the IT state independent of the Thumb-2 mode
ARM: 7878/1: nommu: Implement dummy early_paging_init()
ARM: 7876/1: clear Thumb-2 IT state on exception handling
ARM: 7874/2: bL_switcher: Remove cpu_hotplug_driver_{lock,unlock}()
ARM: footbridge: fix build warnings for netwinder
ARM: 7873/1: vfp: clear vfp_current_hw_state for dying cpu
ARM: fix misplaced arch_virt_to_idmap()
ARM: 7848/1: mcpm: Implement cpu_kill() to synchronise on powerdown
ARM: 7847/1: mcpm: Factor out logical-to-physical CPU translation
ARM: 7869/1: remove unused XSCALE_PMU Kconfig param
ARM: 7864/1: Handle 64-bit memory in case of 32-bit phys_addr_t
ARM: 7863/1: Let arm_add_memory() always use 64-bit arguments
ARM: 7862/1: pcpu: replace __get_cpu_var_uses
ARM: 7861/1: cacheflush: consolidate single-CPU ARMv7 cache disabling code
...
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Conflicts:
arch/arm/include/asm/atomic.h
arch/arm/include/asm/hardirq.h
arch/arm/kernel/smp.c
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The memory pinning code in uaccess_with_memcpy.c does not check
for HugeTLB or THP pmds, and will enter an infinite loop should
a __copy_to_user or __clear_user occur against a huge page.
This patch adds detection code for huge pages to pin_page_for_write.
As this code can be executed in a fast path it refers to the actual
pmds rather than the vma. If a HugeTLB or THP is found (they have
the same pmd representation on ARM), the page table spinlock is
taken to prevent modification whilst the page is pinned.
On ARM, huge pages are only represented as pmds, thus no huge pud
checks are performed. (For huge puds one would lock the page table
in a similar manner as in the pmd case).
Two helper functions are introduced; pmd_thp_or_huge will check
whether or not a page is huge or transparent huge (which have the
same pmd layout on ARM), and pmd_hugewillfault will detect whether
or not a page fault will occur on write to the page.
Running the following test (with the chunking from read_zero
removed):
$ dd if=/dev/zero of=/dev/null bs=10M count=1024
Gave: 2.3 GB/s backed by normal pages,
2.9 GB/s backed by huge pages,
5.1 GB/s backed by huge pages, with page mask=HPAGE_MASK.
After some discussion, it was decided not to adopt the HPAGE_MASK,
as this would have a significant detrimental effect on the overall
system latency due to page_table_lock being held for too long.
This could be revisited if split huge page locks are adopted.
Signed-off-by: Steve Capper <steve.capper@linaro.org>
Reviewed-by: Nicolas Pitre <nico@linaro.org>
Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
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The cost of changing a cacheline from shared to exclusive state can be
significant, especially when this is triggered by an exclusive store,
since it may result in having to retry the transaction.
This patch prefixes our atomic bitops implementation with prefetchw,
to try and grab the line in exclusive state from the start. The testop
macro is left alone, since the barrier semantics limit the usefulness
of prefetching data.
Acked-by: Nicolas Pitre <nico@linaro.org>
Signed-off-by: Will Deacon <will.deacon@arm.com>
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The Shark machine sub-architecture (also known as DNARD, the
DIGITAL Network Appliance Reference Design) lacks a maintainer
able to apply and test patches to modernize the architecture.
It is suspected that the current kernel, while it compiles,
does not even boot on this machine. The listed maintainer has
expressed that he will not be able to spend any time on the
maintenance for the coming year.
So let's delete it from the kernel for now. It can always be
resurrected with git revert if maintenance is resumed.
As the VIA82c505 PCI adapter was only used by this
architecture, that gets deleted too.
Cc: arm@kernel.org
Cc: Alexander Schulz <alex@shark-linux.de>
Signed-off-by: Linus Walleij <linus.walleij@linaro.org>
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