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Help: GDB Remote Debugging with Spike + pk Timing Out on Port 1234 (RV32IMAC)

Hi all,

I'm working with a RISC-V toolchain targeting rv32imac and trying to debug a simple hello.elf program using spike and gdb, but I'm stuck with a timeout issue when GDB tries to connect.

Here's what I have:

Toolchain: `riscv32-unknown-elf-gcc` (newlib)
hello.elf is compiled for RV32IMAC and runs fine with Spike + pk.
`pk` is 32-bit and works correctly.
GDB loads hello.elf correctly.



spike --isa=RV32IMAC /path/to/pk /path/to/hello.elf

This prints the expected output (e.g., “Hello, RISC-V!”).

When I try to launch Spike for remote debugging:

spike --isa=RV32IMAC --rbb-port=1234 /path/to/pk /path/to/hello.elf

It prints:

Listening for remote bitbang connection on port 1234.

Then in another terminal, I run GDB:

riscv32-unknown-elf-gdb /path/to/hello.elf
(gdb) target remote localhost:1234

But I get:

Could not connect: Connection timed out.

I’ve verified the ELF and pk binaries are 32-bit and compatible.
The firewall is disabled, and I'm on a local VM running Ubuntu.
Spike version is 1.1.1-dev (built from source).

# My Questions:

Is --rbb-port expected to work out-of-the-box with rv32imac?
Is there a minimum Spike or pk version required for remote GDB debugging?
Could this be an issue with how Spike is configured or built?

Any suggestions, debugging tips, or example working setups would be much appreciated!

Thanks in advance

https://redd.it/1l9viom
@r_riscv

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8 viewsJun 12 at 21:24

Help: GDB Remote Debugging with Spike + pk Timing Out on Port 1234 (RV32IMAC)

Hi all,

I'm working with a RISC-V toolchain targeting rv32imac and trying to debug a simple hello.elf program using spike and gdb, but I'm stuck with a timeout issue when GDB tries to connect.

Here's what I have:

Toolchain: `riscv32-unknown-elf-gcc` (newlib)
hello.elf is compiled for RV32IMAC and runs fine with Spike + pk.
`pk` is 32-bit and works correctly.
GDB loads hello.elf correctly.



spike --isa=RV32IMAC /path/to/pk /path/to/hello.elf

This prints the expected output (e.g., “Hello, RISC-V!”).

When I try to launch Spike for remote debugging:

spike --isa=RV32IMAC --rbb-port=1234 /path/to/pk /path/to/hello.elf

It prints:

Listening for remote bitbang connection on port 1234.

Then in another terminal, I run GDB:

riscv32-unknown-elf-gdb /path/to/hello.elf
(gdb) target remote localhost:1234

But I get:

Could not connect: Connection timed out.

I’ve verified the ELF and pk binaries are 32-bit and compatible.
The firewall is disabled, and I'm on a local VM running Ubuntu.
Spike version is 1.1.1-dev (built from source).

# My Questions:

Is --rbb-port expected to work out-of-the-box with rv32imac?
Is there a minimum Spike or pk version required for remote GDB debugging?
Could this be an issue with how Spike is configured or built?

Any suggestions, debugging tips, or example working setups would be much appreciated!

Thanks in advance

https://redd.it/1l9viom
@r_riscv

BY RISC-V Reddit