I’ve noticed a very particular situation where my device core dumps and I’m trying to work out why.
Under normal operation (debug.level=2) it all operates as expected, which is:
- Device boots in AP mode with http server enabled
- I connect to the device and enter some network credentials
- I click “save” which triggers a
XMLHttpRequest()that sendswifi.stadata via RPC endpoint - Device reboots and connects to the network
The problem comes when I set debug.level=3. The device core dumps at step 3.
I’ve started with the demo-c project in an attempt to rule out any of the code I’ve added.
main.c is unchanged, mos.yml and index.html changes look like this:
- ["wifi.ap.pass", ""]
- ["wifi.ap.enable", true]
- ["debug.level", 3]
<!DOCTYPE html>
<html>
<body>
<h1>Hello</h1>
<button class="scan" id="save">
Save
</button>
<script>
save.onclick = function () {
var request = new XMLHttpRequest();
var data = JSON.stringify({
config: {
wifi: {
sta: {
"enable": true,
"ssid": "test",
"pass": "1234"
}
}
}
});
request.open('POST', '/rpc/Config.Set', true);
request.setRequestHeader('Content-Type', 'application/x-www-form-urlencoded; charset=UTF-8');
request.send(data);
request.onload = function () {
alert(request.status);
}
};
</script>
</body>
</html>
Clicking the save button from the webpage with debug.level=3 results in a core dump with no real info:
mg_rpc.c:499 0x3ffc8960 CHAN OPEN (HTTP 192.168.4.2:40722)
[May 8 20:40:13.593] mg_rpc.c:526 0x3ffc8960 GOT PARSED FRAME: '' -> '' 64109454 args '{"config":{"wifi":{"sta":{"enable":true,"ssid":"test","pass":"1234"}}}}'
[May 8 20:40:13.607] mg_rpc.c:314 Config.Set via HTTP 192.168.4.2:40722
[May 8 20:40:13.613] Guru Meditation Error: Core 1 panic'ed (LoadProhibited). Exception was unhandled.
[May 8 20:40:13.620]
[May 8 20:40:13.620] Core 1 register dump:
Then debugging the core dump:
Dump contains FreeRTOS task info
Loaded core dump from last snippet in /core
0x40080400 in ?? ()
Unmapped addr 0xdeadbee3
#0 0x40080400 in ?? ()
(gdb)
When debug.level=2 everything works as expected:
[May 8 22:29:26.455] main.c:12 Tick uptime: 47.19, RAM: 253320, 162256 free
[May 8 22:29:27.400] mg_rpc.c:314 Config.Set via HTTP 192.168.4.2:42140
[May 8 22:29:27.425] mg_rpc.c:314 Config.Save via HTTP 192.168.4.2:42140
[May 8 22:29:27.454] main.c:12 Tock uptime: 48.19, RAM: 253312, 160696 free
Any ideas??
Thanks