Xdot Lora

[naushad-rahman]

Description

• Type: Bug
  I am trying to implement Callback function , Example sited by the mbed

#include "mbed.h"

Mutex stdio_mutex;
Thread t2;
Thread t3;
    
void notify(const char* name, int state) {
    stdio_mutex.lock();
    printf("%s: %d\n\r", name, state);
    stdio_mutex.unlock();
}

void test_thread(void const *args) {
    while (true) {
        notify((const char*)args, 0); wait(1);
        notify((const char*)args, 1); wait(1);
    }
}

int main() {
    t2.start(callback(test_thread, (void *)"Th 2"));
    t3.start(callback(test_thread, (void *)"Th 3"));

    test_thread((void *)"Th 1");
}

• Related issue:
  I am getting Hard fault
  output is
  Hard FaulTh 1: 0
  Th 2: 0
  Th 3: 0

Bug

Target
XDot

Toolchain:
GCC_ARM

[0xc0170]

cc @bcostm @adustm @LMESTM @jeromecoutant

[bcostm]

Not an ST device...

[naushad-rahman]

It is ST device

https://developer.mbed.org/platforms/MTS-xDot-L151CC/

[bcostm]

I meant not an ST platform... This platform has been developped by Multitech using a ST mcu yes.
@0xc0170 please change label to devices: multitech

[0xc0170]

@0xc0170 please change label to devices: multitech

I'll do. First thing would be to identify this within the multitech target, and see if this issue applies to a common code base that would affect other targets as well, then this could apply to ST platforms.
Sorry for the initial confusion (I used git history to check who was involved in the codebase for that target, and found only your emails thus I cced you above)

[0xc0170]

cc @mfiore02

[janjongboom]

Is this on mbed OS 5.3.5? If so, downgrading to 5.3.1 might work due to #3823.

[mfiore02]

@naushad-rahman @janjongboom @0xc0170 quick update...

I have a NUCLEO_L152RE on hand and this app looks OK on that platform with mbed-os-5.3.6.

I tested this app on the xDot starting with mbed-os-5.3.6.

Versions 5.3.6 - 5.3.1 all had the same behavior.

Th 1: 0
Hard FaulTh 1: 0
Hard FaulTh 1: 0
Hard FaulTh 1: 0
Hard FaulTh 1: 0
Hard FaulTh 1: 0

Hard faults ad infinitum.

Versions 5.3.0 - 5.2.0 also all had the same behavior.

Th 1: 0

No output after the first line.

I can't go back any further since Callback was introduced in mbed-os-5.2.0.

Debugging time! I'll post again when I know more.

[mfiore02]

@janjongboom based on the progress we've made with #3823 I don't think this issue is related.

[mfiore02]

It looks like the error is encountered during the context switch. Below is the stack trace and register info from the app compiled with mbed-os-5.3.6.

Breakpoint 1, HardFault_Handler ()
    at ./mbed-os/targets/TARGET_STM/TARGET_STM32L1/TARGET_XDOT_L151CC/device/system_stm32l1xx.c:624
624	  printf("Hard Fault\n");
(gdb) bt
#0  HardFault_Handler ()
    at ./mbed-os/targets/TARGET_STM/TARGET_STM32L1/TARGET_XDOT_L151CC/device/system_stm32l1xx.c:624
#1  <signal handler called>
#2  0x20001ec8 in ?? ()
#3  0x08003786 in rt_switch_req (p_new=0x20001a74 <mp_tcb+140>) at ./mbed-os/rtos/rtx/TARGET_CORTEX_M/rt_Task.c:106
#4  0x080035ce in rt_systick () at ./mbed-os/rtos/rtx/TARGET_CORTEX_M/rt_System.c:310
#5  0x080015ec in SysTick_Handler () at HAL_CM3.S:315
Backtrace stopped: previous frame identical to this frame (corrupt stack?)

(gdb) info registers
r0             0x0	0
r1             0x2000163e	536876606
r2             0x0	0
r3             0x20001ec8	536878792
r4             0x20001ca8	536878248
r5             0x0	0
r6             0x20000168	536871272
r7             0x8007fa5	134250405
r8             0x20000168	536871272
r9             0x20000168	536871272
r10            0x2	2
r11            0x800d706	134272774
r12            0x3f9	1017
sp             0x20007f68	0x20007f68
lr             0xfffffff1	-15
pc             0x80041c2	0x80041c2 <HardFault_Handler+2>
xPSR           0x21000003	553648131

Entry 2 in the stack trace is in the processor's RAM, not FLASH. The ?? is also suspicious to me. I'm not a RTOS master, so I'm asking those who are: does the RTOS have components that execute out of RAM instead of FLASH? Or are we having some pointer issues?

[klaas019]

Works as of mbed-os-5.5.7