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Porting OpenBSD to RISC-V Final Report (2020) [pdf] (github.com/mengshili)
93 points by todsacerdoti 26 days ago | hide | past | favorite | 4 comments

Neat tidbit I pulled out of there about GDB:

> GDB was selected as the remote debugger for this project despite the heavy investment in the LLVM toolchain. In practice, GDB proved to be more reliable than the LLVM equivalent for remote debugging the OpenBSD kernel via the QEMU GDB stub.

I wonder if that's a difference in the level of support for risc-v in gdb vs lldb, or maybe that lldb has had less effort put into the "I'm a system debugger" use case, or just an interoperability thing where the QEMU gdb stub mostly gets tested against gdb and not against lldb ?

(One of the unfortunate things about the gdb remote protocol is that there is no kind of test suite or conformance test for implementations of it as either a debug-stub or as a debugger, so testing is often limited to "does this stub work with the debugger I happened to test it against". I'm pretty sure most QEMU developers use gdb, not lldb, when using the gdbstub.)

Check this "See MIPS Run" book on porting Linux to MIPS [1]. Since MIPS has becomes RISC-V, it will be an excellent reference to Linux on RISC-V platform [2].



MIPS has switched from MIPS to RISC-V.

That means anything about old MIPS is now officially obsolete.

That said, MIPS and RISC-V are somewhat similar, as they both are to any other RISC ISA.

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