On Tue 2020-05-19 12:42:35, Joe Perches wrote:
> ARM may have its longest possible command line larger than the longest
> possible printk.
>
> If necessary, emit the commend line on multiple lines.
>
> Signed-off-by: Joe Perches <j...@perches.com>
> ---
>
> compiled, untested
>
> init/main.c | 31 ++++++++++++++++++++++++++++++-
> 1 file changed, 30 insertions(+), 1 deletion(-)
>
> diff --git a/init/main.c b/init/main.c
> index b63a3c001ac4..b3ebbbc129ae 100644
> --- a/init/main.c
> +++ b/init/main.c
> @@ -826,6 +826,34 @@ void __init __weak arch_call_rest_init(void)
> rest_init();
> }
>
> +static void __init print_cmdline(char *line)
> +{
> +#ifdef CONFIG_PRINTK
> + const char *prefix = "Kernel command line";
> + size_t len = strlen(line);
> +
> + while (len > PRINTK_LOG_LINE_MAX) {
> + char *pos = line;
> + char *last_pos = pos + PRINTK_LOG_LINE_MAX - 1;
> + char saved_char;
> + /* Find last space char within the maximum line length */
> + while ((pos = memchr(pos, ' ', len - (pos - line))) &&
> + (pos - line) < PRINTK_LOG_LINE_MAX - 1) {
> + last_pos = pos;
> + }
strchr() would safe the length calculation:
while ((pos = strchr(pos, ' ')) &&
(pos - line) < PRINTK_LOG_LINE_MAX - 1) {
last_pos = pos;
}
> + saved_char = line[last_pos - line];
> + line[last_pos - line] = 0;
This looks less cryptic:
saved_char = *last_pos;
*last_pos = '\0';
> + pr_notice("%s: %s\n", prefix, line);
> + prefix = "Kernel command line (continued)";
> + line[last_pos - line] = saved_char;
> + len -= pos - line;
> + line += pos - line;
'pos' might be NULL when there is no ' ' in the string. What about?
len -= last_pos - line;
line = last_pos;
> + }
> +
> + pr_notice("%s: %s\n", prefix, line);
> +#endif
> +}
Plus, the code should count the prefix length when splitting the line as
reported by Sergey.
Best Regards,
Petr
