Unsure the scope of this bug or the proper fix, so bringing it up here first.
gdbstub.c:gdb_read_register will return 0, and thus E14, when a remote gdb tries to call a function in the exposed linux kernel. This appears to be because the caller expects to be able to receive a generic register size by calling one plus the number of known registers. However, x86_cpu_gdb_read_register() in target/i386/gdbstub.c will only provide register sizes for known registers, since they're not always the same. I'm dealing with this just by shimming 8 whenever gdb_read_register returns 0, but that's obviously not correct. Suggestions? --Dan P.S. call still won't work unless linux is launched with noexec=off noexec32=off, due to NX.