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From:   =?utf-8?B?QmrDtnJuIFTDtnBlbA==?= <bjorn@kernel.org>
To:     Geert Uytterhoeven <geert@linux-m68k.org>
Cc:     Paul Walmsley <paul.walmsley@sifive.com>,
        Palmer Dabbelt <palmer@dabbelt.com>,
        Albert Ou <aou@eecs.berkeley.edu>,
        linux-riscv@lists.infradead.org,
        =?utf-8?B?QmrDtnJuIFTDtnBlbA==?= <bjorn@rivosinc.com>,
        Andreas Schwab <schwab@linux-m68k.org>,
        linux-kernel@vger.kernel.org
Subject: Re: [PATCH v2 1/2] riscv: Add instruction dump to RISC-V splats
In-Reply-To: <CAMuHMdXi7yEiS73YhQAQKqj+3rTCNmuRrdnNKS4prvG96Xgqog@mail.gmail.com>
Date:   Wed, 18 Jan 2023 12:08:56 +0100
Message-ID: <87pmbcnlpz.fsf@all.your.base.are.belong.to.us>
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Geert Uytterhoeven <geert@linux-m68k.org> writes:

>> +static void dump_kernel_instr(const char *loglvl, struct pt_regs *regs)
>> +{
>> +       char str[sizeof("0000 ") * 12 + 2 + 1], *p =3D str;
>> +       unsigned long addr =3D regs->epc;
>
> Given you never use this as an unsigned long, what about
>
>     const u16 *insns =3D (u16 *)instruction_pointer(regs);
>
> so you no longer need casts below?

Indeed! Good suggestion, thank you! I'll do this change in v3.

>> +       long bad;
>> +       u16 val;
>> +       int i;
>> +
>> +       for (i =3D -10; i < 2; i++) {
>> +               bad =3D get_kernel_nofault(val, &((u16 *)addr)[i]);
>> +               if (!bad) {
>> +                       p +=3D sprintf(p, i =3D=3D 0 ? "(%04hx) " : "%04=
hx ", val);
>> +               } else {
>> +                       printk("%sCode: Unable to access instruction at =
0x%lx.\n",
>
> %px, so you can drop the cast to long below.

Much cleaner. Thanks!


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