Re: [RFC][PATCH 1/2] lib: printf: append support of '%*p[Mm][FR]'

From: Joe Perches
Date: Fri Jun 29 2012 - 12:08:03 EST


On Fri, 2012-06-29 at 18:58 +0300, Andy Shevchenko wrote:
> There are many places in the kernel where the drivers print small buffers as a
> hex string. This patch adds a support of the variable width buffer to print it
> as a hex string with a delimiter. The idea came from Pavel Roskin here:
> http://www.digipedia.pl/usenet/thread/18835/17449/

Seems sensible, but one stack caveat below

> diff --git a/lib/vsprintf.c b/lib/vsprintf.c
[]
> @@ -655,11 +655,12 @@ char *resource_string(char *buf, char *end, struct resource *res,
> }
>
> static noinline_for_stack
> -char *mac_address_string(char *buf, char *end, u8 *addr,
> - struct printf_spec spec, const char *fmt)
> +char *hex_string(char *buf, char *end, u8 *addr, struct printf_spec spec,
> + const char *fmt)
> {
> - char mac_addr[sizeof("xx:xx:xx:xx:xx:xx")];
> - char *p = mac_addr;
> + char hex_str[64*3]; /* support up to 64 bytes to print */

Might be too much stack though.


--
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/