Re: [RFC][PATCH] module: Limit line length of module prints

From: Rusty Russell
Date: Fri Dec 11 2015 - 04:40:26 EST


Laura Abbott <labbott@xxxxxxxxxxxxxxxxx> writes:
> print_modules currently uses pr_cont to print all module information.
> This has the side effect of printing lots of modules on one very long
> line. This makes copy/pasting oopses more effort if manual wrapping is
> required. Place a reasonable limit (80 chars) on the number of modules
> on each line.
>
> Signed-off-by: Laura Abbott <labbott@xxxxxxxxxxxxxxxxx>
> ---
> Does this bother anyone else or am I the only one who hates dealing
> with the long lines of "Modules linked in"?

Never bothered me, but I'm a bit odd :) I worry more about the effect
on machine parsing.

Cheers,
Rusty.

> ---
> kernel/module.c | 11 ++++++++++-
> 1 file changed, 10 insertions(+), 1 deletion(-)
>
> diff --git a/kernel/module.c b/kernel/module.c
> index 8f051a1..ace82f1 100644
> --- a/kernel/module.c
> +++ b/kernel/module.c
> @@ -4059,11 +4059,14 @@ struct module *__module_text_address(unsigned long addr)
> }
> EXPORT_SYMBOL_GPL(__module_text_address);
>
> +#define MAX_LINE_CHARS 80
> +
> /* Don't grab lock, we're oopsing. */
> void print_modules(void)
> {
> struct module *mod;
> char buf[8];
> + int cnt = 0;
>
> printk(KERN_DEFAULT "Modules linked in:");
> /* Most callers should already have preempt disabled, but make sure */
> @@ -4071,7 +4074,13 @@ void print_modules(void)
> list_for_each_entry_rcu(mod, &modules, list) {
> if (mod->state == MODULE_STATE_UNFORMED)
> continue;
> - pr_cont(" %s%s", mod->name, module_flags(mod, buf));
> +
> + if (cnt > MAX_LINE_CHARS) {
> + cnt = 0;
> + pr_cont("\n");
> + }
> +
> + cnt += pr_cont(" %s%s", mod->name, module_flags(mod, buf));
> }
> preempt_enable();
> if (last_unloaded_module[0])
> --
> 2.5.0
--
To unsubscribe from this list: send the line "unsubscribe linux-kernel" in
the body of a message to majordomo@xxxxxxxxxxxxxxx
More majordomo info at http://vger.kernel.org/majordomo-info.html
Please read the FAQ at http://www.tux.org/lkml/