Cannot access memory at address 0x8090284

[vmayoral]

Issue here when executing the code.

Cannot access memory at address 0x8090284

message is suspicious. Running out of memory?

[vmayoral]

Note the backtrace:

#0  pthread_mutex_lock (mutex=0x200071e4) at pthread/pthread_mutexlock.c:120
#1  0x080651a0 in rcl_access (p=0x20000340 <dt_byte>) at ../../../dds/src/co/thread.c:444
#2  0x08023b50 in xt_type_delete (tp=0x20000340 <dt_byte>) at ../../../dds/src/xtypes/xtypes.c:2711
#3  0x08038338 in tsm_create_array (lp=0x100047b8, tsm=0x1000327c, iflags=0x10003288) at ../../../dds/src/xtypes/tsm.c:343
#4  0x0803854a in tsm_create_type (lp=0x100047b8, tsm=0x1000327c, iflags=0x10003288) at ../../../dds/src/xtypes/tsm.c:452
#5  0x08037e6c in tsm_create_struct_union (lp=0x100047b8, tsm=0x1000327c, iflags=0x10003288) at ../../../dds/src/xtypes/tsm.c:142
#6  0x0801e316 in DDS_DynamicType_register (tc=0x809f804 <dds_participant_msg_tsm+56>) at ../../../dds/src/xtypes/xtypecode.c:208
#7  0x0807f030 in msg_init () at ../../../dds/src/disc/disc_msg.c:193
#8  0x08081eb2 in spdp_init () at ../../../dds/src/disc/disc_spdp.c:91
#9  0x08053f02 in disc_init () at ../../../dds/src/disc/disc_main.c:992
#10 0x08015c56 in dds_init () at ../../../dds/src/dds/dds.c:1420
#11 0x08044024 in DDS_DomainParticipantFactory_create_participant (domain=0, qos=0x0, listener=0x0, mask=(unknown: 0))
    at ../../../dds/src/dcps/dcps_dpfact.c:76
#12 0x08011064 in dds_chat_main (argc=1, argv=0x10003754) at main.c:532
#13 0x0800348e in task_start () at task/task_start.c:139
#14 0x00000000 in ?? ()

[vmayoral]

When debugging, we clearly can't access

(gdb) x/xw 0x8090284
0x8090284 <pthread_takesemaphore+8>:    Cannot access memory at address 0x8090284

Checking the memory by hand:

0x808fff8 <pthread_mutex_lock+112>:     0xbd8046bd
(gdb) x/xw 0x808fff9
0x808fff9 <pthread_mutex_lock+112>:     0x80bd8046
(gdb) x/xw 0x808fffc
0x808fffc <pthread_mutex_trylock>:      0xb084b580
(gdb) x/xw 0x808fffd
0x808fffd <pthread_mutex_trylock>:      Cannot access memory at address 0x8090000
(gdb) x/xw 0x808fffe
0x808fffe <pthread_mutex_trylock+2>:    Cannot access memory at address 0x8090000

This address is within the 1 MB of Flash available for the STM32F4Discovery. Why is it not possible to access?

We checked the memory protection registers:

(gdb) x/xw 0xe000ed90
0xe000ed90:     0x00000800
(gdb) x/xw 0xe000ed94
0xe000ed94:     0x00000000

[vmayoral]

We've tried a simple "blink" program (no RTOS) and it seems that we are still not able to access those regions of memory:

(gdb) x/xw 0x808fffe
0x808fffe <pthread_mutex_trylock+2>:    Cannot access memory at address 0x8090000

Seems there might be an issue with STLINK.

[vmayoral]

Bug found at stlink. This ros2/stlink@d855279 applies the necessary changes.