I took the RSA example in /nrf/samples/crypto/rsa and added a function foo() to it. I am using nrf5340DK with nrfConnect v1.6.1 and build for cpuapp.
my function foo() uses mbedtls functions heavily and makes a call to mbedtls_entropy_init(entropy)
I get the following exception when the mbedtls_entropy_init(entropy) function is called from foo().
os: ***** USAGE FAULT ***** os: Unaligned memory access r0/a1: 0x00000000 r1/a2: 0x00000000 r2/a3: 0x200331d4 r3/a4: 0x00022845 r12/ip: 0x00000000 r14/lr: 0x00004621 os: xpsr: 0x69000000 os: Faulting instruction address (r15/pc): 0x00023be8 os: >>> ZEPHYR FATAL ERROR 0: CPU exception on CPU 0 os: Current thread: 0x200003c8 (unknown) fatal_error: Resetting system
here is the stack call.
mbedtls_entropy_init( &drbg->entropy );
mbedtls_mutex_init( &ctx->mutex );
mutex_init_platform(){
...
p_mutex = (struct k_mutex *)mutex->mutex; //p_mutex is NOT aligned 0x00022875
k_mutex_init(p_mutex);
...
}
k_mutex_init(p_mutex) --> z_impl_k_mutex_init()
mutex->owner = NULL; <<----- exception happens here.
The rsa program itself makes a call to mutex_init_platform() as well. I checked all the values of p_mutex and all of them are aligned by 8 bytes. However my mbedtls calls leads to unaligned p_mutex values.
I appreciate if you could help me resolve this issue.
