Fixed hang on booting with -d. mtx_enter() was called on an uninitialized

lock.  The quick fix in trap.c was not quite the version tested and had no
effect; back it out.

5 files changed, 18 insertions, 24 deletions

diff --git a/sys/amd64/amd64/machdep.c b/sys/amd64/amd64/machdep.c
index c94fa3d..0e5b0e1 100644
--- a/sys/amd64/amd64/machdep.c
+++ b/sys/amd64/amd64/machdep.c
@@ -1953,6 +1953,12 @@ init386(first)
 	isa_defaultirq();
 #endif
 
+	/*
+	 * Giant is used early for at least debugger traps, unexpected traps,
+	 * and vm86bios initialization.
+	 */
+	mtx_init(&Giant, "Giant", MTX_DEF);
+
 #ifdef DDB
 	kdb_init();
 	if (boothowto & RB_KDB)
@@ -1987,12 +1993,6 @@ init386(first)
 	dblfault_tss.tss_cs = GSEL(GCODE_SEL, SEL_KPL);
 	dblfault_tss.tss_ldt = GSEL(GLDT_SEL, SEL_KPL);
 
-	/*
-	 * We grab Giant during the vm86bios routines, so we need to ensure
-	 * that it is up and running before we use vm86.
-	 */
-	mtx_init(&Giant, "Giant", MTX_DEF);
-
 	vm86_initialize();
 	getmemsize(first);
 
diff --git a/sys/amd64/amd64/trap.c b/sys/amd64/amd64/trap.c
index d49327f..f32dfae 100644
--- a/sys/amd64/amd64/trap.c
+++ b/sys/amd64/amd64/trap.c
@@ -279,8 +279,7 @@ trap(frame)
 		enable_intr();
 	}	
 
-	if (p != NULL || !cold)
-		mtx_enter(&Giant, MTX_DEF);
+	mtx_enter(&Giant, MTX_DEF);
 
 #if defined(I586_CPU) && !defined(NO_F00F_HACK)
 restart:
@@ -640,8 +639,7 @@ restart:
 user:
 	userret(p, &frame, sticks, 1);
 out:
-	if (p != NULL || !cold)
-		mtx_exit(&Giant, MTX_DEF);
+	mtx_exit(&Giant, MTX_DEF);
 }
 
 #ifdef notyet
diff --git a/sys/i386/i386/machdep.c b/sys/i386/i386/machdep.c
index c94fa3d..0e5b0e1 100644
--- a/sys/i386/i386/machdep.c
+++ b/sys/i386/i386/machdep.c
@@ -1953,6 +1953,12 @@ init386(first)
 	isa_defaultirq();
 #endif
 
+	/*
+	 * Giant is used early for at least debugger traps, unexpected traps,
+	 * and vm86bios initialization.
+	 */
+	mtx_init(&Giant, "Giant", MTX_DEF);
+
 #ifdef DDB
 	kdb_init();
 	if (boothowto & RB_KDB)
@@ -1987,12 +1993,6 @@ init386(first)
 	dblfault_tss.tss_cs = GSEL(GCODE_SEL, SEL_KPL);
 	dblfault_tss.tss_ldt = GSEL(GLDT_SEL, SEL_KPL);
 
-	/*
-	 * We grab Giant during the vm86bios routines, so we need to ensure
-	 * that it is up and running before we use vm86.
-	 */
-	mtx_init(&Giant, "Giant", MTX_DEF);
-
 	vm86_initialize();
 	getmemsize(first);
 
diff --git a/sys/i386/i386/trap.c b/sys/i386/i386/trap.c
index d49327f..f32dfae 100644
--- a/sys/i386/i386/trap.c
+++ b/sys/i386/i386/trap.c
@@ -279,8 +279,7 @@ trap(frame)
 		enable_intr();
 	}	
 
-	if (p != NULL || !cold)
-		mtx_enter(&Giant, MTX_DEF);
+	mtx_enter(&Giant, MTX_DEF);
 
 #if defined(I586_CPU) && !defined(NO_F00F_HACK)
 restart:
@@ -640,8 +639,7 @@ restart:
 user:
 	userret(p, &frame, sticks, 1);
 out:
-	if (p != NULL || !cold)
-		mtx_exit(&Giant, MTX_DEF);
+	mtx_exit(&Giant, MTX_DEF);
 }
 
 #ifdef notyet
diff --git a/sys/kern/subr_trap.c b/sys/kern/subr_trap.c
index d49327f..f32dfae 100644
--- a/sys/kern/subr_trap.c
+++ b/sys/kern/subr_trap.c
@@ -279,8 +279,7 @@ trap(frame)
 		enable_intr();
 	}	
 
-	if (p != NULL || !cold)
-		mtx_enter(&Giant, MTX_DEF);
+	mtx_enter(&Giant, MTX_DEF);
 
 #if defined(I586_CPU) && !defined(NO_F00F_HACK)
 restart:
@@ -640,8 +639,7 @@ restart:
 user:
 	userret(p, &frame, sticks, 1);
 out:
-	if (p != NULL || !cold)
-		mtx_exit(&Giant, MTX_DEF);
+	mtx_exit(&Giant, MTX_DEF);
 }
 
 #ifdef notyet