[seL4] Re: Port to a cartesi-machine (riscv:rv64ima)

26 Aug 2021

      Thanks for the timely reply.

I swapped the application to a hello-world[1] to simplify debugging.
Addresses have changed a little (faulting address is now: 0x101d0).
`user exception 0x2 code 0 in thread 0xffffffc17fec8200 "rootserver" at
address 0x101d0`[2].
Its address resolves to frame_dummy seems to be some gcc specific
initialization code (that shouldn't run?)

Since it mentioned registers, I also checked the usage of float
(unsupported in this CPU) but that's likely not it (build has emitted soft
float functions).

[1]
```

#include

int main()
{
    printf("hello world\n");
    return 0;
}

```

[2]
```
(gdb) disas 0x101d0
Dump of assembler code for function frame_dummy:
   0x00000000000101d0 <+0>:     j       0x10182 
   0x00000000000101d2 <+2>:     unimp
```

On Wed, Aug 25, 2021 at 12:59 PM Axel Heider  wrote:
...
Marcelo,
...
I have a suspicion that the unsupported PMP may have something to do
with this but since I'm still pretty new to seL4 so I would like
advice on how to debug this further.
It can't be the PMP because seL4 starts in S-Mode. What code does the
sel4 root task have at the faulting address 0x101f0?
Axel

[seL4] Re: Port to a cartesi-machine (riscv:rv64ima)

Marcelo Politzer