Changes to allow the GENERIC+bhye kernel built from this branch to

run as a 1/2 CPU guest on an 8.1 bhyve host.

bhyve/inout.c
      inout.h
      fbsdrun.c
 - Rather than exiting on accesses to unhandled i/o ports, emulate
   hardware by returning -1 on reads and ignoring writes to unhandled
   ports. Support the previous mode by allowing a 'strict' parameter
   to be set from the command line.
   The 8.1 guest kernel was vastly cut down from GENERIC and had no
   ISA devices. Booting GENERIC exposes a massive amount of random
   touching of i/o ports (hello syscons/vga/atkbdc).

bhyve/consport.c
dev/bvm/bvm_console.c
 - implement a simplistic signature for the bvm console by returning
   'bv' for an inw on the port. Also, set the priority of the console
   to CN_REMOTE if the signature was returned. This works better in
   an environment where multiple consoles are in the kernel (hello syscons)

bhyve/rtc.c
 - return 0 for the access to RTC_EQUIPMENT (yes, you syscons)

amd64/vmm/x86.c
          x86.h
 - hide a bunch more CPUID leaf 1 bits from the guest to prevent
   cpufreq drivers from probing.
   The next step will be to move CPUID handling completely into
   user-space. This will allow the full spectrum of changes from
   presenting a lowest-common-denominator CPU type/feature set, to
   exposing (almost) everything that the host can support.

Reviewed by:	neel
Obtained from:	NetApp

1 files changed, 10 insertions, 6 deletions

diff --git a/sys/dev/bvm/bvm_console.c b/sys/dev/bvm/bvm_console.c
index ac12b6f..392346e 100644
--- a/sys/dev/bvm/bvm_console.c
+++ b/sys/dev/bvm/bvm_console.c
@@ -70,6 +70,8 @@ static int			alt_break_state;
 #define	BVM_CONS_PORT	0x220
 static int bvm_cons_port = BVM_CONS_PORT;
 
+#define BVM_CONS_SIG	('b' << 8 | 'v')
+
 static void	bvm_timeout(void *);
 
 static cn_probe_t	bvm_cnprobe;
@@ -171,14 +173,16 @@ bvm_cnprobe(struct consdev *cp)
 	int disabled, port;
 
 	disabled = 0;
+	cp->cn_pri = CN_DEAD;
+
 	resource_int_value("bvmconsole", 0, "disabled", &disabled);
-	if (disabled)
-		cp->cn_pri = CN_DEAD;
-	else
-		cp->cn_pri = CN_NORMAL;
+	if (!disabled) {
+		if (resource_int_value("bvmconsole", 0, "port", &port) == 0)
+			bvm_cons_port = port;
 
-	if (resource_int_value("bvmconsole", 0, "port", &port) == 0)
-		bvm_cons_port = port;
+		if (inw(bvm_cons_port) == BVM_CONS_SIG)
+			cp->cn_pri = CN_REMOTE;
+	}
 }
 
 static void