Looks good.
I just have some style related comments and 2 questions about the changes.

Address review's comments

Add man page for kvm_kerndisp

Adding Renato Riolino, as he is investigating failing PowerPC tests and this fixes some of them.

Nice, thanks for debugging this issue and documenting psl_userstatic / psl_userset.

• Address review comments

Address review comments

LGTM.
I've tested this by applying the QEMU patch over version 4.2.0 and everything worked fine.

Align src in bcopy/memmove

Fix ifunc resolver parameter name.

Fix ifunc resolver parameter name.

Fix diff, bypassing wrong arcanist copy detection.

• [PPC64] strcpy optimization
• Fix ifunc resolver parameter name
• Merge branch 'master' into luporl-strcpy

About the tests part, I've been using this patch for a couple months now (actually, "RTLD WIP3"), along with ELFv2 and libc optimization patches (D15118, D15368, D15369), and I have observed no issues so far.

In D22767#498741, @cem wrote:

There is some precedent for putting MD gdb code paths in, e.g., sys/powerpc/powerpc/gdb_machdep.c. The naming convention appears to be something like, gdb_cpu_do_offsets(). If you want to put the current gdb_do_offses code there, that would be cool. I would be fine leaving #ifdef __powerpc__ around the qOffsets handler and not implementing it everywhere, given it doesn't seem to be needed on other platforms. It is also fine with me to gdb_do_offset here, until/unless a second arch shows up needing to provide another implementation.

Move implementation of qOffsets to gdb_machdep.c

-Fix qOffsets for 32-bit PowerPC

In D22761#498280, @jhb wrote:

The kgdb bits actually live in github at https://github.com/bsdjhb/gdb/tree/kgdb-8.3 If it's not too hard to make a pull request against that, that would be nicer.
The other thing to consider after that is changing it to be cross-debug friendly. I can help with that. It means not using struct pcb but using a table describing the offsets of the registers from the pcb address.

For remote targets, symbol resolution can be fixed by implementing qOffsets packet handling (D22767).

In D21946#479486, @jhb wrote:

The relocation needs to be done a different way to support, e.g. remote debugging (e.g. attaching gdb to qemu's debug stub). Also, kgdb_main.c is just a simpler wrapper, and 'target vmcore /path/to/vmcore' in plain gdb should also work. I'll have to think about how this might be doable, but this approach is rather hacky. It also won't work for cross-debugging (examining a ppc vmcore on a non-ppc host which kgdb generally supports for other architectures). For PIE executables gdb relies on using the ELF auxv values to find the relocated binary.

Removed the backtrace fix part, that was moved to D22761.

• Fix compiler warning

• Merge with 'master'
• Address review comments

Looks good to me.

Overall the changes look ok to me.

The changes look ok to me. They seem to preserve the original logic, while avoiding the full PTE from PVO conversion.

Looks good.

• Address review's comments
• Fixed an issue in ofw_real_mtx_unlock()

• Merge branch 'master' into luporl-fix-vty
• Address review comments

In D22199#485111, @jhibbits wrote:

The trampoline for ppc64 is at 0x3ffffffffffe000 + offset, in the shared page.

• Merge branch 'master' into luporl-fix-gdb-sigtramp
• Add proper sigtramp detection for ppc64

Fix diff.

Fix diff

• Merge branch 'master'

Looks good.

• make kvatop handle dpcpu/vnet addresses properly

In D21555#473306, @jhibbits wrote:

This is very specific to AIM64 HPT. Can you rename it to kvm_..._hpt.c, or something, and add another key to the header to probe against for the particular pmap implementation? I'll want to add Book-E support, as well as AIM Radix when we do finally get radix stabilized.