lkml.org 
[lkml]   [2013]   [Oct]   [14]   [last100]   RSS Feed
Views: [wrap][no wrap]   [headers]  [forward] 
 
Messages in this thread
Patch in this message
/
Date
From
SubjectRe: [PATCH] init: fix in-place parameter modification regression
On Mon, Oct 14, 2013 at 06:06:23PM +1030, Rusty Russell wrote:
> Krzysztof Mazur <krzysiek@podlesie.net> writes:
> > Before commit 026cee0086fe1df4cf74691cf273062cc769617d
> > ("params: <level>_initcall-like kernel parameters") the __setup
> > parameter parsing code could modify parameter in the
> > static_command_line buffer and such modifications were kept. After
> > that commit such modifications are destroyed during per-initcall level
> > parameter parsing because the same static_command_line buffer is used
> > and only parameters for appropriate initcall level are parsed.
> >
> > That change broke at least parsing "ubd" parameter in the ubd driver
> > when the COW file is used.
> >
> > Now the separate buffer is used for per-initcall parameter parsing,
> > like in parsing early params.
>
> How about just removing "strcpy(static_command_line, saved_command_line);"
> from do_initcall_level altogether? We already initialize it in
> setup_command_line().
>

That does not work because the command line is always modified -
at least '\0' are added to split strings.

To be sure I tested that with:

diff --git a/kernel/params.c b/kernel/params.c
index c00d5b5..606058a 100644
--- a/kernel/params.c
+++ b/kernel/params.c
@@ -96,6 +96,7 @@ static int parse_one(char *param,
unsigned int i;
int err;

+ printk("param %d-%d: %s\n", min_level, max_level, param);
/* Find parameter */
for (i = 0; i < num_params; i++) {
if (parameq(param, params[i].name)) {

And without that strcpy() I get:

[...]
param 0-0: ubd0
param 1-1: ubd0
[...]

instead of:

[...]
param 0-0: ubd0
param 0-0: ubd1
param 0-0: raid
param 0-0: hostfs
param 0-0: root
param 1-1: ubd0
param 1-1: ubd1
param 1-1: raid
param 1-1: hostfs
param 1-1: root
[...]

I checked that also without udb parameters.

Thanks,
Krzysiek


\
 
 \ /
  Last update: 2013-10-14 11:41    [W:0.085 / U:0.596 seconds]
©2003-2020 Jasper Spaans|hosted at Digital Ocean and TransIP|Read the blog|Advertise on this site