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    SubjectRe: [PATCH 3/3] [v4] lib/vsprintf: no_hash_pointers prints all addresses as unhashed
    Hi Marco,

    On Tue, Mar 2, 2021 at 3:40 PM Marco Elver <elver@google.com> wrote:
    > On Tue, 2 Mar 2021 at 15:35, Matthew Wilcox <willy@infradead.org> wrote:
    > > On Tue, Mar 02, 2021 at 03:26:50PM +0100, Marco Elver wrote:
    > > > +static const char no_hash_pointers_warning[9][55] __initconst = {
    > > > + "******************************************************",
    > > > + " NOTICE NOTICE NOTICE NOTICE NOTICE NOTICE NOTICE ",
    > > > + " ",
    > > > + " This system shows unhashed kernel memory addresses ",
    > > > + " via the console, logs, and other interfaces. This ",
    > > > + " might reduce the security of your system. ",
    > > > + " If you see this message and you are not debugging ",
    > > > + " the kernel, report this immediately to your system ",
    > > > + " administrator! ",
    > > > +};
    > > > +
    > > > static int __init no_hash_pointers_enable(char *str)
    > > > {
    > > > + const int lines[] = { 0, 1, 2, 3, 4, 5, 2, 6, 7, 8, 2, 1, 0 };
    > > > + int i;
    > > > +
    > > > no_hash_pointers = true;
    > > >
    > > > - pr_warn("**********************************************************\n");
    > > > - pr_warn("** NOTICE NOTICE NOTICE NOTICE NOTICE NOTICE NOTICE **\n");
    > > > - pr_warn("** **\n");
    > > > - pr_warn("** This system shows unhashed kernel memory addresses **\n");
    > > > - pr_warn("** via the console, logs, and other interfaces. This **\n");
    > > > - pr_warn("** might reduce the security of your system. **\n");
    > > > - pr_warn("** **\n");
    > > > - pr_warn("** If you see this message and you are not debugging **\n");
    > > > - pr_warn("** the kernel, report this immediately to your system **\n");
    > > > - pr_warn("** administrator! **\n");
    > > > - pr_warn("** **\n");
    > > > - pr_warn("** NOTICE NOTICE NOTICE NOTICE NOTICE NOTICE NOTICE **\n");
    > > > - pr_warn("**********************************************************\n");
    > > > + for (i = 0; i < ARRAY_SIZE(lines); i++)
    > > > + pr_warn("**%s**\n", no_hash_pointers_warning[lines[i]]);
    > >
    > > + for (i = 0; i < 3; i++)
    > > + pr_warn("**%s**\n", no_hash_pointers_warning[lines[2 - i]]);
    >
    > Yeah, I had that before, but then wanted to deal with the blank line
    > in the middle of the thing. So I just went with the lines array above,
    > which seemed cleanest for dealing with the middle blank line and
    > footer. Or maybe there's something even nicer I missed? :-)

    Gcc deduplicates the identical strings, so you don't have to go through
    a double indirection at all?

    Gr{oetje,eeting}s,

    Geert

    --
    Geert Uytterhoeven -- There's lots of Linux beyond ia32 -- geert@linux-m68k.org

    In personal conversations with technical people, I call myself a hacker. But
    when I'm talking to journalists I just say "programmer" or something like that.
    -- Linus Torvalds

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