Re: [PATCH 0/4] LoongArch: Add unwinder support

[Huacai Chen]

Hi, Qing,

I think we don't need to CC linux-kernel; on the other hand, CC
linux-arch and Arnd is worthy.
BTW, it seems you are missing V2 in the title.

Huacai

On Mon, Aug 1, 2022 at 8:17 PM Qing Zhang <zhangqing@xxxxxxxxxxx> wrote:
>
> This series in order to add stacktrace suport, Some upcoming features require
> these changes, like trace, divide unwinder into guess unwinder and prologue
> unwinder is to add new unwinders in the future, eg:unwind_frame, unwind_orc .etc.
> Three stages when we do unwind,
>   1) unwind_start(), the prapare of unwinding, fill unwind_state.
>   2) unwind_done(), judge whether the unwind process is finished or not.
>   3) unwind_next_frame(), unwind the next frame.
>
> you can test them by:
>   1) echo t > /proc/sysrq-trigger
>   2) cat /proc/*/stack
>   4) ftrace: function graph
>   5) uprobe: echo 1 > ./options/userstacktrace
>
> Changes from v1 to v2:
>
> - Add the judgment of the offset value of ra in the prologue.
>   (Suggested by Youling).
> - Create an inline function to check the sign bit, which is convenient
>   for extending other types of immediates.  (Suggested by Jinyang).
> - Fix sparse warning :
>     arch/loongarch/include/asm/uaccess.h:232:32: sparse: sparse: incorrect
>     type in argument 2 (different address spaces) @@     expected void const
>     *from @@     got void const [noderef] __user *from @@
> - Add USER_STACKTRACE support as a series.
>
> Qing Zhang (4):
>   LoongArch: Add guess unwinder support
>   LoongArch: Add prologue unwinder support
>   LoongArch: Add stacktrace support
>   LoongArch: Add USER_STACKTRACE support
>
>  arch/loongarch/Kconfig                  |   6 +
>  arch/loongarch/Kconfig.debug            |  28 ++++
>  arch/loongarch/include/asm/inst.h       |  52 +++++++
>  arch/loongarch/include/asm/processor.h  |   9 ++
>  arch/loongarch/include/asm/stacktrace.h |  22 +++
>  arch/loongarch/include/asm/switch_to.h  |  14 +-
>  arch/loongarch/include/asm/uaccess.h    |   4 +-
>  arch/loongarch/include/asm/unwind.h     |  45 +++++++
>  arch/loongarch/kernel/Makefile          |   4 +
>  arch/loongarch/kernel/asm-offsets.c     |   2 +
>  arch/loongarch/kernel/process.c         |  64 +++++++++
>  arch/loongarch/kernel/stacktrace.c      |  79 +++++++++++
>  arch/loongarch/kernel/switch.S          |   2 +
>  arch/loongarch/kernel/traps.c           |  27 ++--
>  arch/loongarch/kernel/unwind_guess.c    |  65 +++++++++
>  arch/loongarch/kernel/unwind_prologue.c | 172 ++++++++++++++++++++++++
>  16 files changed, 577 insertions(+), 18 deletions(-)
>  create mode 100644 arch/loongarch/include/asm/unwind.h
>  create mode 100644 arch/loongarch/kernel/stacktrace.c
>  create mode 100644 arch/loongarch/kernel/unwind_guess.c
>  create mode 100644 arch/loongarch/kernel/unwind_prologue.c
>
> --
> 2.20.1
>
>