From: paul.gortmaker@windriver.com (Paul Gortmaker)
To: linux-arm-kernel@lists.infradead.org
Subject: [PATCH v15 07/10] arm64: kprobes instruction simulation support
Date: Sun, 10 Jul 2016 18:51:27 -0400 [thread overview]
Message-ID: <CAP=VYLp4j8DWAXWS9Dj_EkhTXwUvBZhfyUzGT640ewq+Z4-NZw@mail.gmail.com> (raw)
In-Reply-To: <1467995754-32508-8-git-send-email-dave.long@linaro.org>
On Fri, Jul 8, 2016 at 12:35 PM, David Long <dave.long@linaro.org> wrote:
> From: Sandeepa Prabhu <sandeepa.s.prabhu@gmail.com>
>
> Kprobes needs simulation of instructions that cannot be stepped
> from a different memory location, e.g.: those instructions
> that uses PC-relative addressing. In simulation, the behaviour
> of the instruction is implemented using a copy of pt_regs.
>
> The following instruction categories are simulated:
> - All branching instructions(conditional, register, and immediate)
> - Literal access instructions(load-literal, adr/adrp)
>
> Conditional execution is limited to branching instructions in
> ARM v8. If conditions at PSTATE do not match the condition fields
> of opcode, the instruction is effectively NOP.
>
> Thanks to Will Cohen for assorted suggested changes.
>
> Signed-off-by: Sandeepa Prabhu <sandeepa.s.prabhu@gmail.com>
> Signed-off-by: William Cohen <wcohen@redhat.com>
> Signed-off-by: David A. Long <dave.long@linaro.org>
> Acked-by: Masami Hiramatsu <mhiramat@kernel.org>
> ---
> arch/arm64/include/asm/probes.h | 5 +-
> arch/arm64/kernel/insn.c | 1 +
> arch/arm64/kernel/probes/Makefile | 3 +-
> arch/arm64/kernel/probes/decode-insn.c | 33 ++++-
> arch/arm64/kernel/probes/decode-insn.h | 1 +
> arch/arm64/kernel/probes/kprobes.c | 53 ++++++--
> arch/arm64/kernel/probes/simulate-insn.c | 218 +++++++++++++++++++++++++++++++
> arch/arm64/kernel/probes/simulate-insn.h | 28 ++++
> 8 files changed, 327 insertions(+), 15 deletions(-)
> create mode 100644 arch/arm64/kernel/probes/simulate-insn.c
> create mode 100644 arch/arm64/kernel/probes/simulate-insn.h
>
>
[...]
> diff --git a/arch/arm64/kernel/probes/simulate-insn.c b/arch/arm64/kernel/probes/simulate-insn.c
> new file mode 100644
> index 0000000..429c333
> --- /dev/null
> +++ b/arch/arm64/kernel/probes/simulate-insn.c
> @@ -0,0 +1,218 @@
> +/*
> + * arch/arm64/kernel/probes/simulate-insn.c
> + *
> + * Copyright (C) 2013 Linaro Limited.
> + *
> + * 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 distributed in the hope that it will be useful,
> + * but WITHOUT ANY WARRANTY; without even the implied warranty of
> + * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
> + * General Public License for more details.
> + */
> +
> +#include <linux/kernel.h>
> +#include <linux/kprobes.h>
> +#include <linux/module.h>
Maybe I missed something, but I don't see anything modular about this
code, so why include this?
Paul.
--
> +
> +#include "simulate-insn.h"
> +
> +#define sign_extend(x, signbit) \
> + ((x) | (0 - ((x) & (1 << (signbit)))))
> +
> +#define bbl_displacement(insn) \
> + sign_extend(((insn) & 0x3ffffff) << 2, 27)
> +
> +#define bcond_displacement(insn) \
> + sign_extend(((insn >> 5) & 0x7ffff) << 2, 20)
> + disp = ldr_displacement(opcode);
> + load_addr = (s32 *) (addr + disp);
> +
> + set_x_reg(regs, xn, *load_addr);
> +
> + instruction_pointer_set(regs, instruction_pointer(regs) + 4);
> +}
next prev parent reply other threads:[~2016-07-10 22:51 UTC|newest]
Thread overview: 71+ messages / expand[flat|nested] mbox.gz Atom feed top
2016-07-08 16:35 [PATCH v15 00/10] arm64: Add kernel probes (kprobes) support David Long
2016-07-08 16:35 ` [PATCH v15 01/10] arm64: Add HAVE_REGS_AND_STACK_ACCESS_API feature David Long
2016-07-15 10:57 ` Catalin Marinas
2016-07-15 14:51 ` David Long
2016-07-15 15:13 ` Catalin Marinas
2016-07-15 17:51 ` David Long
2016-07-19 14:17 ` Catalin Marinas
2016-07-08 16:35 ` [PATCH v15 02/10] arm64: Add more test functions to insn.c David Long
2016-07-08 16:35 ` [PATCH v15 03/10] arm64: add conditional instruction simulation support David Long
2016-07-08 16:35 ` [PATCH v15 04/10] arm64: Kprobes with single stepping support David Long
2016-07-20 9:36 ` Marc Zyngier
2016-07-20 11:16 ` Catalin Marinas
2016-07-20 19:08 ` David Long
2016-07-21 8:44 ` Marc Zyngier
2016-07-20 15:49 ` Catalin Marinas
2016-07-21 14:50 ` David Long
2016-07-20 16:09 ` Marc Zyngier
2016-07-20 16:28 ` Catalin Marinas
2016-07-20 16:31 ` Marc Zyngier
2016-07-20 16:46 ` Marc Zyngier
2016-07-20 17:04 ` Catalin Marinas
2016-07-21 16:33 ` David Long
2016-07-21 17:16 ` Catalin Marinas
2016-07-21 17:23 ` Marc Zyngier
2016-07-21 18:33 ` David Long
2016-07-22 10:16 ` Catalin Marinas
2016-07-22 15:51 ` David Long
2016-07-25 17:13 ` Catalin Marinas
2016-07-25 22:27 ` David Long
2016-07-27 11:50 ` Daniel Thompson
2016-07-27 22:13 ` David Long
2016-07-28 14:40 ` Catalin Marinas
2016-07-29 9:01 ` Daniel Thompson
2016-08-04 4:47 ` David Long
2016-08-08 11:13 ` Daniel Thompson
2016-08-08 14:29 ` David Long
2016-08-08 22:49 ` Masami Hiramatsu
2016-08-09 17:23 ` Catalin Marinas
2016-08-10 20:41 ` David Long
2016-08-08 22:19 ` Masami Hiramatsu
2016-07-26 9:50 ` Daniel Thompson
2016-07-26 16:55 ` Catalin Marinas
2016-07-27 10:01 ` Dave Martin
2016-07-26 17:54 ` Mark Rutland
2016-07-27 11:19 ` Daniel Thompson
2016-07-27 11:38 ` Dave Martin
2016-07-27 11:42 ` Daniel Thompson
2016-07-27 13:38 ` Mark Rutland
2016-07-08 16:35 ` [PATCH v15 05/10] arm64: Blacklist non-kprobe-able symbol David Long
2016-07-08 16:35 ` [PATCH v15 06/10] arm64: Treat all entry code as non-kprobe-able David Long
2016-07-15 16:47 ` Catalin Marinas
2016-07-19 0:53 ` David Long
2016-07-08 16:35 ` [PATCH v15 07/10] arm64: kprobes instruction simulation support David Long
2016-07-10 22:51 ` Paul Gortmaker [this message]
2016-07-08 16:35 ` [PATCH v15 08/10] arm64: Add trampoline code for kretprobes David Long
2016-07-19 13:46 ` Catalin Marinas
2016-07-20 18:28 ` David Long
2016-07-08 16:35 ` [PATCH v15 09/10] arm64: Add kernel return probes support (kretprobes) David Long
2016-07-08 16:35 ` [PATCH v15 10/10] kprobes: Add arm64 case in kprobe example module David Long
2016-07-14 16:22 ` [PATCH v15 00/10] arm64: Add kernel probes (kprobes) support Catalin Marinas
2016-07-14 17:09 ` William Cohen
2016-07-15 7:50 ` Catalin Marinas
2016-07-15 8:01 ` Marc Zyngier
2016-07-15 8:59 ` Alex Bennée
2016-07-15 9:04 ` Marc Zyngier
2016-07-15 9:53 ` Marc Zyngier
2016-07-14 17:56 ` David Long
2016-07-19 13:57 ` Catalin Marinas
2016-07-19 14:01 ` David Long
2016-07-19 18:27 ` Catalin Marinas
2016-07-19 19:38 ` David Long
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