BLE: crash after running gc.collect() #5226
Description
Issue split off from #5171 (comment)
I did find however, that the garbage collection is deleting something important to do with BLE. This bug can be replicated by using the snippet sample above by @HexVitor [see below] and using the following steps:
- Establish a BLE connection using something like Serial Bluetooth Terminal on Android
- Send a couple of test messages successfully from Serial Bluetooth Terminal
- Type gc.collect() at the REPL
- Try to send a few more messages and you should eventually see something like the following...
Guru Meditation Error: Core 0 panic'ed (InstrFetchProhibited). Exception was unhandled.
Core 0 register dump:
PC : 0x3ffe67b0 PS : 0x00060530 A0 : 0x80148fdc A1 : 0x3ffbb4a0
A2 : 0x3ffc5cbc A3 : 0x00000010 A4 : 0x00000000 A5 : 0x3ffbb4e0
A6 : 0x3ffc80ec A7 : 0x3ffe67b0 A8 : 0x80148fa1 A9 : 0x00000000
A10 : 0x00000000 A11 : 0x00000010 A12 : 0x3ffbb4e0 A13 : 0x00000002
A14 : 0x0000cdcd A15 : 0x00000001 SAR : 0x00000018 EXCCAUSE: 0x00000014
EXCVADDR: 0x3ffe67b0 LBEG : 0x4014d139 LEND : 0x4014d144 LCOUNT : 0x00000009
ELF file SHA256: 0000000000000000000000000000000000000000000000000000000000000000
Backtrace: 0x3ffe67ad:0x3ffbb4a0 |<-CORRUPTED
Code:
# Import of modules and classes
import bluetooth
# Configuration
ble = bluetooth.BLE()
ble.active(True)
# Event Handling
def ble_irq(event, data):
# print received data
print(ble.gatts_read(rx))
ble.irq(ble_irq)
# GATT Server
UART_UUID = bluetooth.UUID('6E400001-B5A3-F393-E0A9-E50E24DCCA9E')
UART_TX = (bluetooth.UUID('6E400003-B5A3-F393-E0A9-E50E24DCCA9E'), bluetooth.FLAG_READ | bluetooth.FLAG_NOTIFY,)
UART_RX = (bluetooth.UUID('6E400002-B5A3-F393-E0A9-E50E24DCCA9E'), bluetooth.FLAG_WRITE,)
UART_SERVICE = (UART_UUID, (UART_TX, UART_RX,),)
SERVICES = (UART_SERVICE,)
((tx, rx,), ) = ble.gatts_register_services(SERVICES)
# Advertiser
def adv_encode_name(name):
name = bytes(name, 'ascii')
return bytearray((len(name) + 1, 0x09)) + name
ble.gap_advertise(100, bytearray('\x02\x01\x02') + adv_encode_name('ESP32'))