Re: [PATCH] environment: add new global.env.noload parameter

[Ahmad Fatoum <a.fatoum@pengutronix.de>]

Hi,

On 12/1/25 10:37 AM, Sascha Hauer wrote:
> On Fri, Nov 28, 2025 at 06:21:14PM +0100, Ahmad Fatoum wrote:
>> It can be useful for board code to deny loading an environment without
>> disabling it altogether, e.g. to disable load of the environment when
>> entering a recovery mode. Add a global variable that allows for just
>> that.
>>
>> Signed-off-by: Ahmad Fatoum <a.fatoum@pengutronix.de>
>> ---
>>  common/environment.c | 8 +++++++-
>>  1 file changed, 7 insertions(+), 1 deletion(-)
>>
>> diff --git a/common/environment.c b/common/environment.c
>> index d7f5f51cfc6d..d49f255ef007 100644
>> --- a/common/environment.c
>> +++ b/common/environment.c
>> @@ -54,6 +54,7 @@ struct action_data {
>>  #define TMPDIR "/.defaultenv"
>>  
>>  static int global_env_autoprobe = IS_ENABLED(CONFIG_INSECURE);
>> +static int global_env_noload = false;
>>  static char *default_environment_path;
>>  
>>  void default_environment_path_set(const char *path)
>> @@ -455,7 +456,7 @@ int envfs_load(const char *filename, const char *dir, unsigned flags)
>>  	size_t size, rsize;
>>  
>>  #ifdef __BAREBOX__
>> -	if (!IS_ALLOWED(SCONFIG_ENVIRONMENT_LOAD))
>> +	if (!IS_ALLOWED(SCONFIG_ENVIRONMENT_LOAD) || global_env_noload)
>>  		return -EPERM;
> 
> With this you forbid to ever load an environment. The commit message
> suggests you are looking for a way to skip loading of the environment,
> so I would rather expect the check in the caller in common/startup.c

Well, a user could change the value of the variable later, but I agree
checking in common/startup.c makes more sense.

> 
>>  #ifdef __BAREBOX__
>> +
>>  static int register_env_vars(void)
>>  {
>>  	globalvar_add_simple_bool("env.autoprobe", &global_env_autoprobe);
>> +	globalvar_add_simple_bool("env.noload", &global_env_noload);
> 
> globalvars are usually meant for variables that are set/read from the
> shell. What's your usecase for setting this from shell?

This is supposed to set by board code. Shell would be too late.

> Having this as globalvar implies there is a corresponding nvvar. If I
> read the code correctly then setting nv.env.noload=true in the builtin
> default environment will not have the effect that loading of the
> persistent environment is suppressed. Setting nv.env.noload=true in the
> persistent environment obviously also isn't meaningful. The only effect
> will be that a loadenv command no longer works.
> 
> Making this a globalvar seems rather confusing to me.

So you prefer I turn this into a function instead?

Cheers,
Ahmad

> 
> Sascha
> 

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