[PATCH V3] env: Fix invalid env handling in env_init()

[Marek Vasut]

On 4/5/21 6:26 PM, Tim Harvey wrote:
> On Wed, Jan 20, 2021 at 6:45 AM Marek Vasut <marex at denx.de> wrote:
>>
>> This fixes the case where there are multiple environment drivers, one of
>> them is the default environment one, and it is followed by an environment
>> driver which does not implement .init() callback. The default environment
>> driver sets gd->env_valid to ENV_INVALID and returns 0 from its .init()
>> callback implementation, which is valid behavior for default environment.
>>
>> Since the subsequent environment driver does not implement .init(), it
>> also does not modify the $ret variable in the loop. Therefore, the loop
>> is exited with gd->env_valid=ENV_INVALID and ret=0, which means that the
>> code further down in env_init() will not reset the environment to the
>> default one, which is incorrect.
>>
>> This patch sets the $ret variable back to -ENOENT in case the env_valid
>> is set to ENV_INVALID by an environment driver, so that the environment
>> would be correctly reset back to default one, unless a subsequent driver
>> loads a valid environment.
>>
>> Signed-off-by: Marek Vasut <marex at denx.de>
>> ---
>> V2: Reword commit message
>> V3: Rebase
>> ---
>>   env/env.c | 3 +++
>>   1 file changed, 3 insertions(+)
>>
>> diff --git a/env/env.c b/env/env.c
>> index 37b4b54cb75..7faa7ab661b 100644
>> --- a/env/env.c
>> +++ b/env/env.c
>> @@ -334,6 +334,9 @@ int env_init(void)
>>
>>                  debug("%s: Environment %s init done (ret=%d)\n", __func__,
>>                        drv->name, ret);
>> +
>> +               if (gd->env_valid == ENV_INVALID)
>> +                       ret = -ENOENT;
>>          }
>>
>>          if (!prio)
>> --
>> 2.29.2
>>
> 
> Without this patch, multiple environments with MMC being one of them
> fail to work as described in the commit message (becuase MMC does not
> have an init callback). I verified this patch resolves the issue using
> an IMX8M mini with CONFIG_ENV_IS_NOWHERE=y and CONFIG_ENV_IS_IN_MMC=y.
> 
> Tested-By: Tim Harvey <tharvey at gateworks.com>

Thank you. This patch is still missing upstream.