linux-kernel - Re: [PATCH V8 11/22] LoongArch: Add process management

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: <CAK8P3a1ST1hBnhepvoQ9UTbAM=56JEU=-OiBAFQeK2rgaZ5aWw@mail.gmail.com>
Date:   Mon, 21 Mar 2022 09:42:59 +0100
From:   Arnd Bergmann <arnd@...db.de>
To:     Huacai Chen <chenhuacai@...nel.org>
Cc:     Arnd Bergmann <arnd@...db.de>, Andy Lutomirski <luto@...nel.org>,
        Thomas Gleixner <tglx@...utronix.de>,
        Peter Zijlstra <peterz@...radead.org>,
        Andrew Morton <akpm@...ux-foundation.org>,
        David Airlie <airlied@...ux.ie>,
        Jonathan Corbet <corbet@....net>,
        Linus Torvalds <torvalds@...ux-foundation.org>,
        linux-arch <linux-arch@...r.kernel.org>,
        "open list:DOCUMENTATION" <linux-doc@...r.kernel.org>,
        Linux Kernel Mailing List <linux-kernel@...r.kernel.org>,
        Xuefeng Li <lixuefeng@...ngson.cn>,
        Yanteng Si <siyanteng@...ngson.cn>,
        Huacai Chen <chenhuacai@...il.com>,
        Jiaxun Yang <jiaxun.yang@...goat.com>,
        Huacai Chen <chenhuacai@...ngson.cn>
Subject: Re: [PATCH V8 11/22] LoongArch: Add process management

On Sat, Mar 19, 2022 at 3:38 PM Huacai Chen <chenhuacai@...nel.org> wrote:

> +#ifdef CONFIG_PAGE_SIZE_64KB
> +#define THREAD_SIZE_ORDER (0)
> +#endif
> +
> +#define THREAD_SIZE (PAGE_SIZE << THREAD_SIZE_ORDER)
> +#define THREAD_MASK (THREAD_SIZE - 1UL)
> +

Having a 64KB stack area is rather wasteful. I think you should use a sub-page
allocation in this configuration, or possibly disallow 64KB page configuration
entirely.

Note that you have to use full pages when using CONFIG_VMAP_STACK, but
you don't seem to support that at the moment, so allocating only 16KB stacks
on a 64KB page config should still work.

       Arnd