linux-toradex.git/arch/arm/include/asm/processor.h, branch v3.4.73 Linux kernel for Apalis and Colibri modules Merge branch 'for-linus' of git://git.linaro.org/people/rmk/linux-arm 2012-03-29T23:53:48+00:00 Linus Torvalds torvalds@linux-foundation.org 2012-03-29T23:53:48+00:00 12679a2d7e3bfbdc7586e3e86d1ca90c46659363 Pull more ARM updates from Russell King. This got a fair number of conflicts with the <asm/system.h> split, but also with some other sparse-irq and header file include cleanups. They all looked pretty trivial, though. * 'for-linus' of git://git.linaro.org/people/rmk/linux-arm: (59 commits) ARM: fix Kconfig warning for HAVE_BPF_JIT ARM: 7361/1: provide XIP_VIRT_ADDR for no-MMU builds ARM: 7349/1: integrator: convert to sparse irqs ARM: 7259/3: net: JIT compiler for packet filters ARM: 7334/1: add jump label support ARM: 7333/2: jump label: detect %c support for ARM ARM: 7338/1: add support for early console output via semihosting ARM: use set_current_blocked() and block_sigmask() ARM: exec: remove redundant set_fs(USER_DS) ARM: 7332/1: extract out code patch function from kprobes ARM: 7331/1: extract out insn generation code from ftrace ARM: 7330/1: ftrace: use canonical Thumb-2 wide instruction format ARM: 7351/1: ftrace: remove useless memory checks ARM: 7316/1: kexec: EOI active and mask all interrupts in kexec crash path ARM: Versatile Express: add NO_IOPORT ARM: get rid of asm/irq.h in asm/prom.h ARM: 7319/1: Print debug info for SIGBUS in user faults ARM: 7318/1: gic: refactor irq_start assignment ARM: 7317/1: irq: avoid NULL check in for_each_irq_desc loop ARM: 7315/1: perf: add support for the Cortex-A7 PMU ... 
Pull more ARM updates from Russell King.

This got a fair number of conflicts with the <asm/system.h> split, but
also with some other sparse-irq and header file include cleanups.  They
all looked pretty trivial, though.

* 'for-linus' of git://git.linaro.org/people/rmk/linux-arm: (59 commits)
  ARM: fix Kconfig warning for HAVE_BPF_JIT
  ARM: 7361/1: provide XIP_VIRT_ADDR for no-MMU builds
  ARM: 7349/1: integrator: convert to sparse irqs
  ARM: 7259/3: net: JIT compiler for packet filters
  ARM: 7334/1: add jump label support
  ARM: 7333/2: jump label: detect %c support for ARM
  ARM: 7338/1: add support for early console output via semihosting
  ARM: use set_current_blocked() and block_sigmask()
  ARM: exec: remove redundant set_fs(USER_DS)
  ARM: 7332/1: extract out code patch function from kprobes
  ARM: 7331/1: extract out insn generation code from ftrace
  ARM: 7330/1: ftrace: use canonical Thumb-2 wide instruction format
  ARM: 7351/1: ftrace: remove useless memory checks
  ARM: 7316/1: kexec: EOI active and mask all interrupts in kexec crash path
  ARM: Versatile Express: add NO_IOPORT
  ARM: get rid of asm/irq.h in asm/prom.h
  ARM: 7319/1: Print debug info for SIGBUS in user faults
  ARM: 7318/1: gic: refactor irq_start assignment
  ARM: 7317/1: irq: avoid NULL check in for_each_irq_desc loop
  ARM: 7315/1: perf: add support for the Cortex-A7 PMU
  ...
Disintegrate asm/system.h for ARM 2012-03-28T17:30:01+00:00 David Howells dhowells@redhat.com 2012-03-28T17:30:01+00:00 9f97da78bf018206fb623cd351d454af2f105fe0 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 
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
ARM: exec: remove redundant set_fs(USER_DS) 2012-03-24T09:38:55+00:00 Mathias Krause minipli@googlemail.com 2012-03-05T23:05:34+00:00 e88443cdfc61af5cd22d6aeb245ee94833c473bc The address limit is already set in flush_old_exec() so this set_fs(USER_DS) is redundant. Signed-off-by: Mathias Krause <minipli@googlemail.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk> 
The address limit is already set in flush_old_exec() so this
set_fs(USER_DS) is redundant.

Signed-off-by: Mathias Krause <minipli@googlemail.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
ARM: 7327/1: need to include asm/system.h in asm/processor.h 2012-02-15T21:10:49+00:00 Olof Johansson olof@lixom.net 2012-02-15T20:17:12+00:00 fee6a3c33a8f137f39cd9997b0476411f73576c7 For files that include asm/processor.h but not asm/system.h: arch/arm/mach-msm/include/mach/uncompress.h: In function 'putc': arch/arm/mach-msm/include/mach/uncompress.h:48:3: error: implicit declaration of function 'smp_mb' [-Werror=implicit-function-declaration] In this case, smp_mb() is from the cpu_relax() call in the msm putc(). It likely went uncaught when the uncompress.h change went in since the defconfig didn't enable that code path, but later changes (e76f4750f4: ARM: debug: arrange Kconfig options more logically) resulted in the option being on for msm_defconfig and thus exposed it. Signed-off-by: Olof Johansson <olof@lixom.net> Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk> 
For files that include asm/processor.h but not asm/system.h:

arch/arm/mach-msm/include/mach/uncompress.h: In function 'putc':
arch/arm/mach-msm/include/mach/uncompress.h:48:3: error: implicit declaration of function 'smp_mb' [-Werror=implicit-function-declaration]

In this case, smp_mb() is from the cpu_relax() call in the msm putc().

It likely went uncaught when the uncompress.h change went in since the
defconfig didn't enable that code path, but later changes (e76f4750f4:
ARM: debug: arrange Kconfig options more logically) resulted in the
option being on for msm_defconfig and thus exposed it.

Signed-off-by: Olof Johansson <olof@lixom.net>
Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
ARM: 7169/1: topdown mmap support 2011-12-06T11:15:25+00:00 Rob Herring rob.herring@calxeda.com 2011-11-22T03:01:07+00:00 7dbaa466780a754154531b44c2086f6618cee3a8 Similar to other architectures, this adds topdown mmap support in user process address space allocation policy. This allows mmap sizes greater than 2GB. This support is largely copied from MIPS and the generic implementations. The address space randomization is moved into arch_pick_mmap_layout. Tested on V-Express with ubuntu and a mmap test from here: https://bugs.launchpad.net/bugs/861296 Signed-off-by: Rob Herring <rob.herring@calxeda.com> Acked-by: Nicolas Pitre <nico@linaro.org> Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk> 
Similar to other architectures, this adds topdown mmap support in user
process address space allocation policy. This allows mmap sizes greater
than 2GB. This support is largely copied from MIPS and the generic
implementations.

The address space randomization is moved into arch_pick_mmap_layout.

Tested on V-Express with ubuntu and a mmap test from here:
https://bugs.launchpad.net/bugs/861296

Signed-off-by: Rob Herring <rob.herring@calxeda.com>
Acked-by: Nicolas Pitre <nico@linaro.org>
Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
Merge branch 'misc' into devel 2011-03-16T23:35:25+00:00 Russell King rmk+kernel@arm.linux.org.uk 2011-03-16T23:35:25+00:00 1f0090a1eaa1b750a2fc5c99c91b790d5322a1fd Conflicts: arch/arm/Kconfig 
Conflicts:
	arch/arm/Kconfig
ARM: 6784/1: errata: no automatic Store Buffer drain on Cortex-A9 2011-03-09T21:40:18+00:00 Will Deacon will.deacon@arm.com 2011-03-04T11:38:54+00:00 5dab26af1bacad9a7189d904fbc8b4fe8e95dd81 On revisions of the Cortex-A9 prior to r2p0, the Store Buffer does not have any automatic draining mechanism and therefore a livelock may occur if an external agent continuously polls a memory location waiting to observe an update. This workaround defines cpu_relax() as smp_mb(), preventing correctly written polling loops from denying visibility of updates to memory. Acked-by: Catalin Marinas <catalin.marinas@arm.com> Signed-off-by: Will Deacon <will.deacon@arm.com> Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk> 
On revisions of the Cortex-A9 prior to r2p0, the Store Buffer does not
have any automatic draining mechanism and therefore a livelock may occur
if an external agent continuously polls a memory location waiting to
observe an update.

This workaround defines cpu_relax() as smp_mb(), preventing correctly
written polling loops from denying visibility of updates to memory.

Acked-by: Catalin Marinas <catalin.marinas@arm.com>
Signed-off-by: Will Deacon <will.deacon@arm.com>
Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
ARM: 6668/1: ptrace: remove single-step emulation code 2011-02-23T17:24:22+00:00 Will Deacon will.deacon@arm.com 2011-02-14T13:31:09+00:00 425fc47adb5bb69f76285be77a09a3341a30799e PTRACE_SINGLESTEP is a ptrace request designed to offer single-stepping support to userspace when the underlying architecture has hardware support for this operation. On ARM, we set arch_has_single_step() to 1 and attempt to emulate hardware single-stepping by disassembling the current instruction to determine the next pc and placing a software breakpoint on that location. Unfortunately this has the following problems: 1.) Only a subset of ARMv7 instructions are supported 2.) Thumb-2 is unsupported 3.) The code is not SMP safe We could try to fix this code, but it turns out that because of the above issues it is rarely used in practice. GDB, for example, uses PTRACE_POKETEXT and PTRACE_PEEKTEXT to manage breakpoints itself and does not require any kernel assistance. This patch removes the single-step emulation code from ptrace meaning that the PTRACE_SINGLESTEP request will return -EIO on ARM. Portable code must check the return value from a ptrace call and handle the failure gracefully. Acked-by: Nicolas Pitre <nicolas.pitre@linaro.org> Signed-off-by: Will Deacon <will.deacon@arm.com> Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk> 
PTRACE_SINGLESTEP is a ptrace request designed to offer single-stepping
support to userspace when the underlying architecture has hardware
support for this operation.

On ARM, we set arch_has_single_step() to 1 and attempt to emulate hardware
single-stepping by disassembling the current instruction to determine the
next pc and placing a software breakpoint on that location.

Unfortunately this has the following problems:

1.) Only a subset of ARMv7 instructions are supported
2.) Thumb-2 is unsupported
3.) The code is not SMP safe

We could try to fix this code, but it turns out that because of the above
issues it is rarely used in practice.  GDB, for example, uses PTRACE_POKETEXT
and PTRACE_PEEKTEXT to manage breakpoints itself and does not require any
kernel assistance.

This patch removes the single-step emulation code from ptrace meaning that
the PTRACE_SINGLESTEP request will return -EIO on ARM. Portable code must
check the return value from a ptrace call and handle the failure gracefully.

Acked-by: Nicolas Pitre <nicolas.pitre@linaro.org>
Signed-off-by: Will Deacon <will.deacon@arm.com>
Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
ARM: 6357/1: hw-breakpoint: add new ptrace requests for hw-breakpoint interaction 2010-09-08T09:05:00+00:00 Will Deacon will.deacon@arm.com 2010-09-03T09:42:55+00:00 864232fa1a2f8dfe003438ef0851a56722740f3e For debuggers to take advantage of the hw-breakpoint framework in the kernel, it is necessary to expose the API calls via a ptrace interface. This patch exposes the hardware breakpoints framework as a collection of virtual registers, accesible using PTRACE_SETHBPREGS and PTRACE_GETHBPREGS requests. The breakpoints are stored in the debug_info struct of the running thread. Cc: Frederic Weisbecker <fweisbec@gmail.com> Cc: S. Karthikeyan <informkarthik@gmail.com> Signed-off-by: Will Deacon <will.deacon@arm.com> Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk> 
For debuggers to take advantage of the hw-breakpoint framework in the kernel,
it is necessary to expose the API calls via a ptrace interface.

This patch exposes the hardware breakpoints framework as a collection of
virtual registers, accesible using PTRACE_SETHBPREGS and PTRACE_GETHBPREGS
requests. The breakpoints are stored in the debug_info struct of the running
thread.

Cc: Frederic Weisbecker <fweisbec@gmail.com>
Cc: S. Karthikeyan <informkarthik@gmail.com>
Signed-off-by: Will Deacon <will.deacon@arm.com>
Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
ARM: 6194/1: change definition of cpu_relax() for ARM11MPCore 2010-07-01T09:13:52+00:00 Will Deacon will.deacon@arm.com 2010-06-21T14:29:03+00:00 534be1d5a2da940ecc5e528992ea4ace8658157a Linux expects that if a CPU modifies a memory location, then that modification will eventually become visible to other CPUs in the system. On an ARM11MPCore processor, loads are prioritised over stores so it is possible for a store operation to be postponed if a polling loop immediately follows it. If the variable being polled indirectly depends on the outstanding store [for example, another CPU may be polling the variable that is pending modification] then there is the potential for deadlock if interrupts are disabled. This deadlock occurs in the KGDB testsuire when executing on an SMP ARM11MPCore configuration. This patch changes the definition of cpu_relax() to smp_mb() for ARMv6 cores, forcing a flushing of the write buffer on SMP systems before the next load takes place. If the Kernel is not compiled for SMP support, this will expand to a barrier() as before. Acked-by: Catalin Marinas <catalin.marinas@arm.com> Signed-off-by: Will Deacon <will.deacon@arm.com> Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk> 
Linux expects that if a CPU modifies a memory location, then that
modification will eventually become visible to other CPUs in the system.

On an ARM11MPCore processor, loads are prioritised over stores so it is
possible for a store operation to be postponed if a polling loop immediately
follows it. If the variable being polled indirectly depends on the outstanding
store [for example, another CPU may be polling the variable that is pending
modification] then there is the potential for deadlock if interrupts are
disabled. This deadlock occurs in the KGDB testsuire when executing on an
SMP ARM11MPCore configuration.

This patch changes the definition of cpu_relax() to smp_mb() for ARMv6 cores,
forcing a flushing of the write buffer on SMP systems before the next load
takes place. If the Kernel is not compiled for SMP support, this will expand
to a barrier() as before.

Acked-by: Catalin Marinas <catalin.marinas@arm.com>
Signed-off-by: Will Deacon <will.deacon@arm.com>
Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>