MFV r274272 and diff reduction with upstream.

Illumos issue:
    5244 zio pipeline callers should explicitly invoke next stage

Tested with:	ztest plus ZFS over GELI configuration
MFC after:	1 month
Merge remote-tracking branch 'freebsd/master' into hardened/current/master
Merge remote-tracking branch 'origin/hardened/current/master' into hardened/current/hardening
Merge remote-tracking branch 'origin/hardened/current/master' into hardened/current/segvguard
Merge remote-tracking branch 'origin/hardened/current/master' into hardened/current/ptrace
Merge remote-tracking branch 'origin/hardened/current/master' into hardened/current/log
Merge remote-tracking branch 'origin/hardened/current/master' into hardened/current/userlandenhanced
Merge remote-tracking branch 'origin/hardened/current/master' into hardened/current/chacha
Merge remote-tracking branch 'origin/hardened/current/master' into hardened/current/pie
Merge remote-tracking branch 'origin/hardened/current/master' into hardened/current/aout
Merge remote-tracking branch 'origin/hardened/current/master' into hardened/current/unstable
Merge remote-tracking branch 'origin/hardened/current/hardening' into hardened/current/unstable
Merge remote-tracking branch 'origin/hardened/current/segvguard' into hardened/current/unstable
Merge remote-tracking branch 'origin/hardened/current/ptrace' into hardened/current/unstable
Merge remote-tracking branch 'origin/hardened/current/log' into hardened/current/unstable
Merge remote-tracking branch 'origin/hardened/current/userlandenhanced' into hardened/current/unstable
Merge remote-tracking branch 'origin/hardened/current/pie' into hardened/current/unstable
Merge remote-tracking branch 'origin/hardened/current/chacha' into hardened/current/unstable
Merge remote-tracking branch 'origin/hardened/current/aout' into hardened/current/unstable