svn commit: r354756 - in head/sys: kern sys

[Scott Long]

Author: scottl
Date: Fri Nov 15 23:27:17 2019
New Revision: 354756
URL: https://svnweb.freebsd.org/changeset/base/354756

Log:
  Create a new sysctl subtree, machdep.mitigations.  Its purpose is to organize
  knobs and indicators for code that mitigates functional and security issues
  in the architecture/platform.  Controls for regular operational policy should
  still go into places security, hw, kern, etc.
  
  The machdep root node is inherently architecture dependent, but mitigations
  tend to be architecture dependent as well.  Some cases like Spectre do cross
  architectural boundaries, but the mitigation code for them tends to be
  architecture dependent anyways, and multiple architectures won't be active
  in the same image of the kernel.
  
  Many mitigation knobs already exist in the system, and they will be moved
  with compat naming in the future.  Going forward, mitigations should collect
  in machdep.mitigations.
  
  Reviewed by:	imp, brooks, rwatson, emaste, jhb
  Sponsored by:	Intel

Modified:
  head/sys/kern/kern_mib.c
  head/sys/sys/sysctl.h

Modified: head/sys/kern/kern_mib.c
==============================================================================
--- head/sys/kern/kern_mib.c	Fri Nov 15 23:12:19 2019	(r354755)
+++ head/sys/kern/kern_mib.c	Fri Nov 15 23:27:17 2019	(r354756)
@@ -78,6 +78,8 @@ SYSCTL_ROOT_NODE(CTL_HW,	  hw,     CTLFLAG_RW, 0,
 	"hardware");
 SYSCTL_ROOT_NODE(CTL_MACHDEP, machdep, CTLFLAG_RW, 0,
 	"machine dependent");
+SYSCTL_NODE(_machdep, OID_AUTO, mitigations, CTLFLAG_RW, 0,
+	"Machine dependent platform mitigations.");
 SYSCTL_ROOT_NODE(CTL_USER,	  user,   CTLFLAG_RW, 0,
 	"user-level");
 SYSCTL_ROOT_NODE(CTL_P1003_1B,  p1003_1b,   CTLFLAG_RW, 0,

Modified: head/sys/sys/sysctl.h
==============================================================================
--- head/sys/sys/sysctl.h	Fri Nov 15 23:12:19 2019	(r354755)
+++ head/sys/sys/sysctl.h	Fri Nov 15 23:27:17 2019	(r354756)
@@ -1094,6 +1094,7 @@ SYSCTL_DECL(_hw_bus);
 SYSCTL_DECL(_hw_bus_devices);
 SYSCTL_DECL(_hw_bus_info);
 SYSCTL_DECL(_machdep);
+SYSCTL_DECL(_machdep_mitigations);
 SYSCTL_DECL(_user);
 SYSCTL_DECL(_compat);
 SYSCTL_DECL(_regression);