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From:   Huacai Chen <chenhuacai@kernel.org>
Date:   Mon, 14 Nov 2022 12:31:51 +0800
Message-ID: <CAAhV-H47oPC6mYkeDh7NfmvL2jAHO32ugM-PK2mmFY6XdqF8_Q@mail.gmail.com>
Subject: Re: [PATCH v2 0/5] Add kprobe and kretprobe support for LoongArch
To:     Tiezhu Yang <yangtiezhu@loongson.cn>
Cc:     Masami Hiramatsu <mhiramat@kernel.org>, loongarch@lists.linux.dev,
        linux-kernel@vger.kernel.org
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Hi, Tiezhu,

Thanks for your patches, however,
1, You should rebase your code, since some functions such as
is_pc_insn is provided in the github's loongarch-next branch;
2, Your code may have some problems about preemption, you can do
something like this commit [1];
3, I don't think Kprobe should be enabled by default, distribution
configs can enable it if needed.

[1] https://github.com/loongson/linux/commit/023d5412ab5c154b87d57d70d465a4243df53717

Huacai

On Wed, Sep 28, 2022 at 8:50 AM Tiezhu Yang <yangtiezhu@loongson.cn> wrote:
>
> v2:
>   -- Split simu_branch() and simu_pc() into a single patch
>   -- Call kprobe_page_fault() in do_page_fault()
>   -- Add kprobes_trampoline.S for kretprobe
>
> Tiezhu Yang (5):
>   LoongArch: Simulate branch and PC instructions
>   LoongArch: Add kprobe support
>   LoongArch: Add kretprobe support
>   samples/kprobes: Add LoongArch support
>   LoongArch: Enable KPROBES in default config
>
>  arch/loongarch/Kconfig                     |   2 +
>  arch/loongarch/configs/loongson3_defconfig |   1 +
>  arch/loongarch/include/asm/inst.h          |  31 +++
>  arch/loongarch/include/asm/kprobes.h       |  44 ++++
>  arch/loongarch/include/asm/ptrace.h        |   1 +
>  arch/loongarch/kernel/Makefile             |   2 +
>  arch/loongarch/kernel/inst.c               | 113 ++++++++++
>  arch/loongarch/kernel/kprobes.c            | 336 +++++++++++++++++++++++++++++
>  arch/loongarch/kernel/kprobes_trampoline.S |  97 +++++++++
>  arch/loongarch/mm/fault.c                  |   3 +
>  samples/kprobes/kprobe_example.c           |   8 +
>  11 files changed, 638 insertions(+)
>  create mode 100644 arch/loongarch/include/asm/kprobes.h
>  create mode 100644 arch/loongarch/kernel/kprobes.c
>  create mode 100644 arch/loongarch/kernel/kprobes_trampoline.S
>
> --
> 2.1.0
>