[PATCH 4/5] sandbox: implement reset

[Heinrich Schuchardt]

On 27.10.20 05:52, Simon Glass wrote:
> Hi Heinrich,
>
> On Sun, 25 Oct 2020 at 00:04, Heinrich Schuchardt <xypron.glpk at gmx.de> wrote:
>>
>> Up to now the sandbox would shutdown upon a cold reset request. Instead it
>> should be reset.
>>
>> In our coding we use static variables. The only safe way to return to an
>> initial state is to relaunch the U-Boot binary.
>
> This is unfortunate, but I suspect you may be right. Have you looked at it?

I am not so much worried about the sandbox specific code, where you find
static variables like:

arch/sandbox/cpu/os.c:165:static bool term_setup;
arch/sandbox/cpu/os.c:166:static bool term_nonblock;

My worry is about the main U-Boot where it is completely legal to expect
that static variables are initialized, e.g.

lib/efi_loader/efi_boottime.c:28:LIST_HEAD(efi_obj_list);
lib/efi_loader/efi_boottime.c:34:LIST_HEAD(efi_event_queue);
lib/efi_loader/efi_boottime.c:40:LIST_HEAD(efi_register_notify_events);

Best regards

Heinrich

>
>>
>> The reset implementation uses a longjmp() to return to the main() function
>> and then relaunches U-Boot using execv().
>>
>> Signed-off-by: Heinrich Schuchardt <xypron.glpk at gmx.de>