From jhb@freebsd.org Tue Dec 29 15:55:34 2015 Date: Tue, 29 Dec 2015 14:52:43 -0500 From: John Baldwin To: monthly@freebsd.org Subject: GDB report Updates to GDB John Baldwin jhb@FreeBSD.org New 1:1-only thread target for FreeBSD

The KGDB option is now on by default in the devel/gdb port. The changes to support cross-debugging of crashdumps in libkvm were committed to HEAD in r291406. A new thread target for FreeBSD that is suitable for merging upstream has been written and lightly tested. However, it is not yet available as an option in the port. This thread target uses ptrace(2) directly rather than libthread_db and as such supports threads on all ABIs (such as FreeBSD/i386 binaries on FreeBSD/amd64 and possibly Linux binaries though that is not yet tested). It also requires less invasive changes in the MD targets in GDB compared to the libthread_db-based target.

Add a port option for the new 1:1-only thread target. Test the new 1:1-only thread target. Figure out why the powerpc kgdb targets are not able to unwind the stack past the initial frame. Add support for more platforms (arm, mips, aarch64) to upstream gdb for both userland and kgdb. Add support for debugging powerpc vector registers. -- John Baldwin