linux-kernel - Re: [PATCH] LoongArch: Add unaligned access support

lists.openwall.net		lists / announce owl-users owl-dev john-users john-dev passwdqc-users yescrypt popa3d-users / oss-security kernel-hardening musl sabotage tlsify passwords / crypt-dev xvendor / Bugtraq Full-Disclosure linux-kernel linux-netdev linux-ext4 linux-hardening linux-cve-announce PHC
Open Source and information security mailing list archives

Hash Suite: Windows password security audit tool. GUI, reports in PDF.

[<prev] [next>] [<thread-prev] [thread-next>] [day] [month] [year] [list]

Message-ID: <c1b674a37a1a04f9c84df1e9a227db68bf78e922.camel@xry111.site>
Date:   Sun, 16 Oct 2022 23:04:42 +0800
From:   Xi Ruoyao <xry111@...111.site>
To:     Huacai Chen <chenhuacai@...ngson.cn>,
        Huacai Chen <chenhuacai@...nel.org>
Cc:     loongarch@...ts.linux.dev, Xuefeng Li <lixuefeng@...ngson.cn>,
        Tiezhu Yang <yangtiezhu@...ngson.cn>,
        Guo Ren <guoren@...nel.org>, Xuerui Wang <kernel@...0n.name>,
        Jiaxun Yang <jiaxun.yang@...goat.com>,
        linux-kernel@...r.kernel.org
Subject: Re: [PATCH] LoongArch: Add unaligned access support

On Sun, 2022-10-16 at 21:34 +0800, Huacai Chen wrote:

> Loongson-2 series (Loongson-2K500, Loongson-2K1000)

"2K1000LA"? "2K1000" is puzzling because of a name conflict with the
MIPS-based model.

/* snip */

> +static inline unsigned long read_fpr(unsigned int fd)
> +{
> +#define READ_FPR(fd, __value)          \
> +{                                      \

Unnecessary curly brace pair.

> +       __asm__ __volatile__(           \
> +       "movfr2gr.d\t%0, $f%1\n\t"      \
> +       : "=r"(__value) : "i"(fd));     \
> +}

I'm not sure if this is a correct use of "i" constraint.  Maybe we
should just concatenate the string?

"movfr2gr.d\t%0, $f" #fd "\n\t"

> +
> +       unsigned long __value;
> +
> +       switch (fd) {

I don't like this "very long" switch statement, but it seems we have no
way to make it better...

> +       case 0:
> +               READ_FPR(0, __value);
> +               break;
> +       case 1:
> +               READ_FPR(1, __value);
> +               break;
> +       case 2:
> +               READ_FPR(2, __value);
> +               break;

-- 
Xi Ruoyao <xry111@...111.site>
School of Aerospace Science and Technology, Xidian University