Re: [PATCH v2 1/2] Add support for extlinux.conf

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

Hello Alexander,

On 5/5/26 3:01 PM, Alexander Shiyan wrote:
> There is another question: is it necessary to call
> globalvar_remove("linux.bootargs.dyn.bootentries")
> in extlinux_entry_free()?
> We can run bootm multiple times in dry-run mode, and the variable may
> become invalid...

The boot_entry() function takes care to set all
global.linux.bootargs.dyn.* variables to the empty string:

	globalvar_set_match("linux.bootargs.dyn.", "");

So you should not need to explicitly remove it.

Cheers,
Ahmad

> 
> вт, 5 мая 2026 г. в 15:52, Ahmad Fatoum <a.fatoum@pengutronix.de>:
>>
>> Hi,
>>
>> On 5/5/26 2:44 PM, Alexander Shiyan wrote:
>>> barebox@Diasom DS-RK3568-SOM-EVB:/ global
>>
>>> Loading ARM aarch64 Linux/EFI image '/mnt/mmc1.2/boot/extlinux/../vmlinuz'
>>> Camera IMX662 detected.
>>> commandline: console=ttyS2,1500000n8 root=LABEL=ROOT ro
>>> systemd.unit=setup.target quiet splash  root=/dev/mmcblk1p3
>>> systemd.machine_id=181af2816b4c6b0aef77068e0ccc69ad
>>> Loaded kernel to 0x0a400000, devicetree at 0x000000000fb49000
>>> nv variables modified, saving them
>>> I/TC: Secondary CPU 1 initializing
>>> I/TC: Secondary CPU 1 switching to normal world boot
>>> I/TC: Secondary CPU 2 initializing
>>> I/TC: Secondary CPU 2 switching to normal world boot
>>> I/TC: Secondary CPU 3 initializing
>>> I/TC: Secondary CPU 3 switching to normal world boot
>>>
>>> Now it works!
>>
>> Great. I think with the rest of my feedback integrated, the v3 should be
>> good to go.
>>
>> Thanks,
>> Ahmad
>>
>>>
>>> вт, 5 мая 2026 г. в 15:22, Ahmad Fatoum <a.fatoum@pengutronix.de>:
>>>>
>>>> Hello Alexander,
>>>>
>>>> On 5/5/26 2:19 PM, Alexander Shiyan wrote:
>>>>> barebox@Diasom DS-RK3568-SOM-EVB:/ global
>>>>> * bootm.~appendroot: true
>>>>
>>>> This should be bootm.appendroot: 1.
>>>>
>>>>> bootm.~appendroot: true, but now is ever not added to the cmdline.
>>>>
>>>> The tilde is just an implementation detail in common/bootm.c. You should
>>>> just global.bootm.appendroot as before.
>>>>
>>>> Thanks,
>>>> Ahmad
>>>>
>>>>>
>>>>> вт, 5 мая 2026 г. в 13:49, Ahmad Fatoum <a.fatoum@pengutronix.de>:
>>>>>>
>>>>>> Hello Alexander,
>>>>>>
>>>>>> On 5/5/26 12:47 PM, Alexander Shiyan wrote:
>>>>>>> Hello Ahmad.
>>>>>>>
>>>>>>> ...
>>>>>>>>> +     if (e->append) {
>>>>>>>>> +             char *append;
>>>>>>>>> +
>>>>>>>>> +             /*
>>>>>>>>> +              * The same rootfs image may be launched from eMMC or SD card.
>>>>>>>>> +              * Remove any hardcoded root= parameter from "append" to avoid
>>>>>>>>> +              * conflicts, then let barebox automatically add the correct
>>>>>>>>> +              * root= (via global.bootm.appendroot) based on the boot device.
>>>>>>>>> +              */
>>>>>>>>> +             if (data.appendroot)
>>>>>>>>> +                     append = remove_param(e->append, "ROOT=");
>>>>>>> ...
>>>>>>>> I thus have a question to you: What happens if you drop remove_param()
>>>>>>>> completely? Sure we will have two root=, but the later gets precedence,
>>>>>>>> so your use case would continue to work without giving users a wrong
>>>>>>>> expectation.
>>>>>>>
>>>>>>> Yes, the second one takes priority.
>>>>>>> The second one is the one added via extlinux.conf APPEND option.
>>>>>>> In our case we need the first parameter, i.e. which comes from barebox
>>>>>>> when global.bootm.appendroot is toggled on.
>>>>>>
>>>>>> Ack. Please check the series I Cc'd you on, which ensures that
>>>>>> global.bootm.appendroot applies _after_ extlinux.conf APPEND.
>>>>>>
>>>>>> Thanks,
>>>>>> Ahmad
>>>>>>
>>>>>>>
>>>>>>> Thanks!
>>>>>>>
>>>>>>
>>>>>> --
>>>>>> Pengutronix e.K.                  |                             |
>>>>>> Steuerwalder Str. 21              | http://www.pengutronix.de/  |
>>>>>> 31137 Hildesheim, Germany         | Phone: +49-5121-206917-0    |
>>>>>> Amtsgericht Hildesheim, HRA 2686  | Fax:   +49-5121-206917-5555 |
>>>>>>
>>>>>
>>>>
>>>> --
>>>> Pengutronix e.K.                  |                             |
>>>> Steuerwalder Str. 21              | http://www.pengutronix.de/  |
>>>> 31137 Hildesheim, Germany         | Phone: +49-5121-206917-0    |
>>>> Amtsgericht Hildesheim, HRA 2686  | Fax:   +49-5121-206917-5555 |
>>>>
>>>
>>
>> --
>> Pengutronix e.K.                  |                             |
>> Steuerwalder Str. 21              | http://www.pengutronix.de/  |
>> 31137 Hildesheim, Germany         | Phone: +49-5121-206917-0    |
>> Amtsgericht Hildesheim, HRA 2686  | Fax:   +49-5121-206917-5555 |
>>
> 

-- 
Pengutronix e.K.                  |                             |
Steuerwalder Str. 21              | http://www.pengutronix.de/  |
31137 Hildesheim, Germany         | Phone: +49-5121-206917-0    |
Amtsgericht Hildesheim, HRA 2686  | Fax:   +49-5121-206917-5555 |