This patch introduce kprobeopt for ARM 32. Limitations: - Currently only kernel compiled with ARM ISA is supported. - Offset between probe point and optinsn slot must not larger than 32MiB. Masami Hiramatsu suggests replacing 2 words, it will make things complex. Futher patch can make such optimization. Kprobe opt on ARM is relatively simpler than kprobe opt on x86 because ARM instruction is always 4 bytes aligned and 4 bytes long. This patch replace probed instruction by a 'b', branch to trampoline code and then calls optimized_callback(). optimized_callback() calls opt_pre_handler() to execute kprobe handler. It also emulate/simulate replaced instruction. When unregistering kprobe, the deferred manner of unoptimizer may leave branch instruction before optimizer is called. Different from x86_64, which only copy the probed insn after optprobe_template_end and reexecute them, this patch call singlestep to emulate/simulate the insn directly. Futher patch can optimize this behavior. Signed-off-by: Wang Nan <wangnan0@huawei.com> Acked-by: Masami Hiramatsu <masami.hiramatsu.pt@hitachi.com> Cc: Will Deacon <will.deacon@arm.com> Reviewed-by: Jon Medhurst (Tixy) <tixy@linaro.org> Signed-off-by: Jon Medhurst <tixy@linaro.org>
In discussion on LKML (https://lkml.org/lkml/2014/11/28/158), Russell King suggests to move all probe related code to arch/arm/probes. This patch does the work. Due to dependency on 'arch/arm/kernel/patch.h', this patch also moves patch.h to 'arch/arm/include/asm/patch.h', and related '#include' directives are also midified to '#include <asm/patch.h>'. Following is an overview of this patch: ./arch/arm/kernel/ ./arch/arm/probes/ |-- Makefile |-- Makefile |-- probes-arm.c ==> |-- decode-arm.c |-- probes-arm.h ==> |-- decode-arm.h |-- probes-thumb.c ==> |-- decode-thumb.c |-- probes-thumb.h ==> |-- decode-thumb.h |-- probes.c ==> |-- decode.c |-- probes.h ==> |-- decode.h | |-- kprobes | | |-- Makefile |-- kprobes-arm.c ==> | |-- actions-arm.c |-- kprobes-common.c ==> | |-- actions-common.c |-- kprobes-thumb.c ==> | |-- actions-thumb.c |-- kprobes.c ==> | |-- core.c |-- kprobes.h ==> | |-- core.h |-- kprobes-test-arm.c ==> | |-- test-arm.c |-- kprobes-test.c ==> | |-- test-core.c |-- kprobes-test.h ==> | |-- test-core.h |-- kprobes-test-thumb.c ==> | `-- test-thumb.c | `-- uprobes | |-- Makefile |-- uprobes-arm.c ==> |-- actions-arm.c |-- uprobes.c ==> |-- core.c |-- uprobes.h ==> `-- core.h | `-- patch.h ==> arch/arm/include/asm/patch.h Signed-off-by: Wang Nan <wangnan0@huawei.com> Acked-by: Masami Hiramatsu <masami.hiramatsu.pt@hitachi.com> Signed-off-by: Jon Medhurst <tixy@linaro.org>
Pull char/misc driver updates from Greg KH: "Here's the big char/misc driver update for 3.19-rc1 Lots of little things all over the place in different drivers, and a new subsystem, "coresight" has been added. Full details are in the shortlog" * tag 'char-misc-3.19-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/gregkh/char-misc: (73 commits) parport: parport_pc, do not remove parent devices early spmi: Remove shutdown/suspend/resume kernel-doc carma-fpga-program: drop videobuf dependency carma-fpga: drop videobuf dependency carma-fpga-program.c: fix compile errors i8k: Fix temperature bug handling in i8k_get_temp() cxl: Name interrupts in /proc/interrupt CXL: Return error to PSL if IRQ demultiplexing fails & print clearer warning coresight-replicator: remove .owner field for driver coresight: fixed comments in coresight.h coresight: fix typo in comment in coresight-priv.h coresight: bindings for coresight drivers coresight: Adding ABI documentation w1: support auto-load of w1_bq27000 module. w1: avoid potential u16 overflow cn: verify msg->len before making callback mei: export fw status registers through sysfs mei: read and print all six FW status registers mei: txe: add cherrytrail device id mei: kill cached host and me csr values ...
Pull ARM updates from Russell King:
"The major updates included in this update are:
- Clang compatible stack pointer accesses by Behan Webster.
- SA11x0 updates from Dmitry Eremin-Solenikov.
- kgdb handling of breakpoints with read-only text/modules
- Support for Privileged-no-execute feature on ARMv7 to prevent
userspace code execution by the kernel.
- AMBA primecell bus handling of irq-safe runtime PM
- Unwinding support for memset/memzero/memmove/memcpy functions
- VFP fixes for Krait CPUs and improvements in detecting the VFP
architecture
- A number of code cleanups (using pr_*, removing or reducing the
severity of a couple of kernel messages, splitting ftrace asm code
out to a separate file, etc.)
- Add machine name to stack dump output"
* 'for-linus' of git://ftp.arm.linux.org.uk/~rmk/linux-arm: (62 commits)
ARM: 8247/2: pcmcia: sa1100: make use of device clock
ARM: 8246/2: pcmcia: sa1111: provide device clock
ARM: 8245/1: pcmcia: soc-common: enable/disable socket clocks
ARM: 8244/1: fbdev: sa1100fb: make use of device clock
ARM: 8243/1: sa1100: add a clock alias for sa1111 pcmcia device
ARM: 8242/1: sa1100: add cpu clock
ARM: 8221/1: PJ4: allow building in Thumb-2 mode
ARM: 8234/1: sa1100: reorder IRQ handling code
ARM: 8233/1: sa1100: switch to hwirq usage
ARM: 8232/1: sa1100: merge GPIO multiplexer IRQ to "normal" irq domain
ARM: 8231/1: sa1100: introduce irqdomains support
ARM: 8230/1: sa1100: shift IRQs by one
ARM: 8229/1: sa1100: replace irq numbers with names in irq driver
ARM: 8228/1: sa1100: drop entry-macro.S
ARM: 8227/1: sa1100: switch to MULTI_IRQ_HANDLER
ARM: 8241/1: Update processor_modes for hyp and monitor mode
ARM: 8240/1: MCPM: document mcpm_sync_init()
ARM: 8239/1: Introduce {set,clear}_pte_bit
ARM: 8238/1: mm: Refine set_memory_* functions
ARM: 8237/1: fix flush_pfn_alias
...
Two files that get included when building the multi_v7_defconfig target fail to build when selecting THUMB2_KERNEL for this configuration. In both cases, we can just build the file as ARM code, as none of its symbols are exported to modules, so there are no interworking concerns. In the iwmmxt.S case, add ENDPROC() declarations so the symbols are annotated as functions, resulting in the linker to emit the appropriate mode switches. Acked-by: Nicolas Pitre <nico@linaro.org> Tested-by: Olof Johansson <olof@lixom.net> Signed-off-by: Ard Biesheuvel <ard.biesheuvel@linaro.org> Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
The ftrace assembly code doesn't need to live in entry-common.S and be surrounded with #ifdef CONFIG_FUNCTION_TRACER. Instead, move it to its own file and conditionally assemble it. Tested-by: Felipe Balbi <balbi@ti.com> Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
Removing minimal support for etb/etm to favour an implementation that is more flexible, extensible and capable of handling more platforms. Also removing the only client of the old driver. That code can easily be replaced by entries for etb/etm in the device tree. Signed-off-by: Mathieu Poirier <mathieu.poirier@linaro.org> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
The ARM callchain handling code is currently bundled with the ARM PMU management code, despite the two having no dependency on each other. This bundling has the unfortunate property of making callchain handling depend on CONFIG_HW_PERF_EVENTS, even though the callchain handling could be applied to software events in the absence of PMU hardware support. This patch separates the two, placing the callchain handling in perf_callchain.c and making it depend on CONFIG_PERF_EVENTS rather than CONFIG_HW_PERF_EVENTS, enabling callchain recording on kernels built without hardware perf event support. Signed-off-by: Mark Rutland <mark.rutland@arm.com> Reviewed-by: Will Deacon <will.deacon@arm.com> Signed-off-by: Will Deacon <will.deacon@arm.com>
Handle the case where someone has set the text segment of the kernel as read-only by using the newly introduced "patch" mechanism. Signed-off-by: Doug Anderson <dianders@chromium.org> [kees: switched structure size check to BUILD_BUG_ON (sboyd)] Signed-off-by: Kees Cook <keescook@chromium.org> Acked-by: Nicolas Pitre <nico@linaro.org>