[External] Re: [PATCH v2] riscv: Dump user opcode bytes on fatal faults

[yunhui cui]

Hi Björn,

On Wed, Aug 16, 2023 at 11:11 PM Björn Töpel <bjorn at kernel.org> wrote:
>
> Hi Yunhui,
>
> Waking up the dead! ;-)
>

>
> X86's show_opcodes() is used both for kernel oops:es, and userland
> unhandled signals. On RISC-V there's dump_kernel_instr() added in commit
> eb165bfa8eaf ("riscv: Add instruction dump to RISC-V splats").
>
> Wdyt about reworking that function, so that it works for userland epc as
> well? I think it's useful to have the surrounding instruction context,
> and not just on instruction.

Okay,  Based on your suggestion, I'm going to rename dump_kernel_instr
to dump_instr. Like:
static void dump_instr(const char *loglvl, struct pt_regs *regs)
{
...
                if (user_mode(regs))
                        bad = get_user_nofault(val, &insns[i]);
                else
                        bad = get_kernel_nofault(val, &insns[i]);
...
}

What do you think?

Thanks,
Yunhui