ARC: disasm: handle ARCv2 case in kprobe get/set functions

Current implementation of get_reg/set_reg implies ARCompact layout
of pt_regs structure. Meanwhile pt_regs structure differs between
ARCompact and ARCv2. Update those functions to handle ARCv2.

Tested-by: kernel test robot <lkp@intel.com>
Signed-off-by: Sergey Matyukevich <sergey.matyukevich@synopsys.com>
Signed-off-by: Vineet Gupta <vgupta@kernel.org>

ARC: Remove a redundant memset()

disasm_instr() already call memset(0) on its 2nd argument, so there is no
need to clear it explicitly before calling this function.

Remove the redundant memset().

Signed-off-by: Christophe JAILLET <christophe.jaillet@wanadoo.fr>
Signed-off-by: Vineet Gupta <vgupta@kernel.org>

ARC: fix typos in comments

Various spelling mistakes in comments.
Detected with the help of Coccinelle.

Signed-off-by: Julia Lawall <Julia.Lawall@inria.fr>
Signed-off-by: Vineet Gupta <vgupta@kernel.org>

treewide: Use fallthrough pseudo-keyword

Replace the existing /* fall through */ comments and its variants with
the new pseudo-keyword macro fallthrough[1]. Also, remove unnecessary
fall-through markings when it is the case.

[1] https://www.kernel.org/doc/html/v5.7/process/deprecated.html?highlight=fallthrough#implicit-switch-case-fall-through

Signed-off-by: Gustavo A. R. Silva <gustavoars@kernel.org>

treewide: Replace GPLv2 boilerplate/reference with SPDX - rule 500

Based on 2 normalized pattern(s):

this program is free software you can redistribute it and or modify
it under the terms of the gnu general public license version 2 as
published by the free software foundation

this program is free software you can redistribute it and or modify
it under the terms of the gnu general public license version 2 as
published by the free software foundation #

extracted by the scancode license scanner the SPDX license identifier

GPL-2.0-only

has been chosen to replace the boilerplate/reference in 4122 file(s).

Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Reviewed-by: Enrico Weigelt <info@metux.net>
Reviewed-by: Kate Stewart <kstewart@linuxfoundation.org>
Reviewed-by: Allison Randal <allison@lohutok.net>
Cc: linux-spdx@vger.kernel.org
Link: https://lkml.kernel.org/r/20190604081206.933168790@linutronix.de
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

ARC: rename kconfig option for unaligned emulation

Signed-off-by: Vineet Gupta <vgupta@synopsys.com>

ARC: Use <linux/*> headers instead of <asm/*>

Silences the following checkpatch warnings:
WARNING: Use #include <linux/ptrace.h> instead of <asm/ptrace.h>
WARNING: Use #include <linux/kprobes.h> instead of <asm/kprobes.h>
WARNING: Use #include <linux/kgdb.h> instead of <asm/kgdb.h>
WARNING: Use #include <linux/uaccess.h> instead of <asm/uaccess.h>
WARNING: Use #include <linux/cache.h> instead of <asm/cache.h>

Signed-off-by: Sachin Kamat <sachin.kamat@linaro.org>
Signed-off-by: Vineet Gupta <vgupta@synopsys.com>

arc: fix incorrect ifdef comment

Signed-off-by: Paul Bolle <pebolle@tiscali.nl>
Signed-off-by: Jiri Kosina <jkosina@suse.cz>

ARC: Unaligned access emulation

ARC700 doesn't natively support unaligned access, but can be emulated
-Unaligned Access Exception
-Disassembly at the Fault address to find the exact insn (long/short)

Also per Arnd's comment, we runtime control it using 2 sysctl knobs:
* SYSCTL_ARCH_UNALIGN_ALLOW: Runtime enable/disble
* SYSCTL_ARCH_UNALIGN_NO_WARN: Warn on each emulation attempt

Originally contributed by Tim Yao <tim.yao@amlogic.com>

Signed-off-by: Vineet Gupta <vgupta@synopsys.com>
Cc: Tim Yao <tim.yao@amlogic.com>
Acked-by: Arnd Bergmann <arnd@arndb.de>

ARC: kprobes support

Origin port done by Rajeshwar Ranga

Signed-off-by: Vineet Gupta <vgupta@synopsys.com>
Cc: Rajeshwar Ranga <rajeshwar.ranga@gmail.com>

ARC: disassembly (needed by kprobes/kgdb/unaligned-access-emul)

In-kernel disassembler

Due Credits
* Orig written by Rajeshwar Ranga
* Consolidation/cleanups by Mischa Jonker

Signed-off-by: Vineet Gupta <vgupta@synopsys.com>
Cc: Rajeshwar Ranga <rajeshwar.ranga@gmail.com>
Cc: Mischa Jonker <mjonker@synopsys.com>