10 files changed, 117 insertions, 53 deletions

diff --git a/sys/amd64/amd64/trap.c b/sys/amd64/amd64/trap.c
index d41318cd4c6d..415d695c2842 100644
--- a/sys/amd64/amd64/trap.c
+++ b/sys/amd64/amd64/trap.c
@@ -145,9 +145,7 @@ static int panic_on_nmi = 1;
 SYSCTL_INT(_machdep, OID_AUTO, panic_on_nmi, CTLFLAG_RW,
 	&panic_on_nmi, 0, "Panic on NMI");
 
-#ifdef WITNESS
 extern char *syscallnames[];
-#endif
 
 /*
  * Exception, fault, and trap interface to the FreeBSD kernel.
@@ -874,6 +872,19 @@ syscall(frame)
 	}
 
 	/*
+	 * Check for misbehavior.
+	 */
+	WITNESS_WARN(WARN_PANIC, NULL, "System call %s returning",
+	    (code >= 0 && code < SYS_MAXSYSCALL) ? syscallnames[code] : "???");
+	KASSERT(td->td_critnest == 0,
+	    ("System call %s returning in a critical section",
+	    (code >= 0 && code < SYS_MAXSYSCALL) ? syscallnames[code] : "???"));
+	KASSERT(td->td_locks == 0,
+	    ("System call %s returning with %d locks held",
+	    (code >= 0 && code < SYS_MAXSYSCALL) ? syscallnames[code] : "???",
+	    td->td_locks));
+
+	/*
 	 * Handle reschedule and other end-of-syscall issues
 	 */
 	userret(td, &frame);
@@ -894,9 +905,4 @@ syscall(frame)
 	STOPEVENT(p, S_SCX, code);
 
 	PTRACESTOP_SC(p, td, S_PT_SCX);
-
-	WITNESS_WARN(WARN_PANIC, NULL, "System call %s returning",
-	    (code >= 0 && code < SYS_MAXSYSCALL) ? syscallnames[code] : "???");
-	mtx_assert(&sched_lock, MA_NOTOWNED);
-	mtx_assert(&Giant, MA_NOTOWNED);
 }
diff --git a/sys/amd64/ia32/ia32_syscall.c b/sys/amd64/ia32/ia32_syscall.c
index 5b3086a9d4f5..644235dc3bf9 100644
--- a/sys/amd64/ia32/ia32_syscall.c
+++ b/sys/amd64/ia32/ia32_syscall.c
@@ -244,6 +244,19 @@ ia32_syscall(struct trapframe frame)
 	}
 
 	/*
+	 * Check for misbehavior.
+	 */
+	WITNESS_WARN(WARN_PANIC, NULL, "System call %s returning",
+	    (code >= 0 && code < SYS_MAXSYSCALL) ? freebsd32_syscallnames[code] : "???");
+	KASSERT(td->td_critnest == 0,
+	    ("System call %s returning in a critical section",
+	    (code >= 0 && code < SYS_MAXSYSCALL) ? freebsd32_syscallnames[code] : "???"));
+	KASSERT(td->td_locks == 0,
+	    ("System call %s returning with %d locks held",
+	    (code >= 0 && code < SYS_MAXSYSCALL) ? freebsd32_syscallnames[code] : "???",
+	    td->td_locks));
+
+	/*
 	 * Handle reschedule and other end-of-syscall issues
 	 */
 	userret(td, &frame);
@@ -263,11 +276,6 @@ ia32_syscall(struct trapframe frame)
 	STOPEVENT(p, S_SCX, code);
  
 	PTRACESTOP_SC(p, td, S_PT_SCX);
-
-	WITNESS_WARN(WARN_PANIC, NULL, "System call %s returning",
-	    (code >= 0 && code < SYS_MAXSYSCALL) ? freebsd32_syscallnames[code] : "???");
-	mtx_assert(&sched_lock, MA_NOTOWNED);
-	mtx_assert(&Giant, MA_NOTOWNED);
 }
 
 
diff --git a/sys/arm/arm/trap.c b/sys/arm/arm/trap.c
index b1534fe5d092..1cb53dbcc3c8 100644
--- a/sys/arm/arm/trap.c
+++ b/sys/arm/arm/trap.c
@@ -133,6 +133,7 @@ void undefinedinstruction(trapframe_t *);
 #include <machine/machdep.h>
  
 extern char fusubailout[];
+extern char *syscallnames[];
 
 #ifdef DEBUG
 int last_fault_code;	/* For the benefit of pmap_fault_fixup() */
@@ -979,8 +980,17 @@ bad:
 	}
 	if (locked && (callp->sy_narg & SYF_MPSAFE) == 0)
 		mtx_unlock(&Giant);
-	
-	
+
+	WITNESS_WARN(WARN_PANIC, NULL, "System call %s returning",
+	    (code >= 0 && code < SYS_MAXSYSCALL) ? syscallnames[code] : "???");
+	KASSERT(td->td_critnest == 0,
+	    ("System call %s returning in a critical section",
+	    (code >= 0 && code < SYS_MAXSYSCALL) ? syscallnames[code] : "???"));
+	KASSERT(td->td_locks == 0,
+	    ("System call %s returning with %d locks held",
+	    (code >= 0 && code < SYS_MAXSYSCALL) ? syscallnames[code] : "???",
+	    td->td_locks));
+
 	userret(td, frame);
 	CTR4(KTR_SYSC, "syscall exit thread %p pid %d proc %s code %d", td,
 	    td->td_proc->p_pid, td->td_proc->p_comm, code);
@@ -991,8 +1001,6 @@ bad:
       	if (KTRPOINT(td, KTR_SYSRET))
 		ktrsysret(code, error, td->td_retval[0]);
 #endif
-	mtx_assert(&sched_lock, MA_NOTOWNED);
-	mtx_assert(&Giant, MA_NOTOWNED);
 }
 
 void
diff --git a/sys/conf/files b/sys/conf/files
index 24c8cf5b5cec..a02023bc480d 100644
--- a/sys/conf/files
+++ b/sys/conf/files
@@ -1402,7 +1402,7 @@ kern/sys_generic.c		standard
 kern/sys_pipe.c			standard
 kern/sys_process.c		standard
 kern/sys_socket.c		standard
-kern/syscalls.c			optional witness
+kern/syscalls.c			optional witness | invariants
 kern/sysv_ipc.c			standard
 kern/sysv_msg.c			optional sysvmsg
 kern/sysv_sem.c			optional sysvsem
diff --git a/sys/i386/i386/trap.c b/sys/i386/i386/trap.c
index cce7038a2543..da3ed95f4152 100644
--- a/sys/i386/i386/trap.c
+++ b/sys/i386/i386/trap.c
@@ -159,9 +159,7 @@ static int panic_on_nmi = 1;
 SYSCTL_INT(_machdep, OID_AUTO, panic_on_nmi, CTLFLAG_RW,
 	&panic_on_nmi, 0, "Panic on NMI");
 
-#ifdef WITNESS
 extern char *syscallnames[];
-#endif
 
 /*
  * Exception, fault, and trap interface to the FreeBSD kernel.
@@ -1065,6 +1063,19 @@ syscall(frame)
 	}
 
 	/*
+	 * Check for misbehavior.
+	 */
+	WITNESS_WARN(WARN_PANIC, NULL, "System call %s returning",
+	    (code >= 0 && code < SYS_MAXSYSCALL) ? syscallnames[code] : "???");
+	KASSERT(td->td_critnest == 0,
+	    ("System call %s returning in a critical section",
+	    (code >= 0 && code < SYS_MAXSYSCALL) ? syscallnames[code] : "???"));
+	KASSERT(td->td_locks == 0,
+	    ("System call %s returning with %d locks held",
+	    (code >= 0 && code < SYS_MAXSYSCALL) ? syscallnames[code] : "???",
+	    td->td_locks));
+
+	/*
 	 * Handle reschedule and other end-of-syscall issues
 	 */
 	userret(td, &frame);
@@ -1085,10 +1096,5 @@ syscall(frame)
 	STOPEVENT(p, S_SCX, code);
 
 	PTRACESTOP_SC(p, td, S_PT_SCX);
-
-	WITNESS_WARN(WARN_PANIC, NULL, "System call %s returning",
-	    (code >= 0 && code < SYS_MAXSYSCALL) ? syscallnames[code] : "???");
-	mtx_assert(&sched_lock, MA_NOTOWNED);
-	mtx_assert(&Giant, MA_NOTOWNED);
 }
 
diff --git a/sys/ia64/ia32/ia32_trap.c b/sys/ia64/ia32/ia32_trap.c
index c3cacf5c6b65..f63ae941b6fe 100644
--- a/sys/ia64/ia32/ia32_trap.c
+++ b/sys/ia64/ia32/ia32_trap.c
@@ -46,9 +46,7 @@ __FBSDID("$FreeBSD$");
 #include <machine/md_var.h>
 #include <i386/include/psl.h>
 
-#ifdef WITNESS
 extern char *syscallnames[];
-#endif
 
 static void
 ia32_syscall(struct trapframe *tf)
@@ -183,6 +181,19 @@ ia32_syscall(struct trapframe *tf)
 	}
 
 	/*
+	 * Check for misbehavior.
+	 */
+	WITNESS_WARN(WARN_PANIC, NULL, "System call %s returning",
+	    (code >= 0 && code < SYS_MAXSYSCALL) ? syscallnames[code] : "???");
+	KASSERT(td->td_critnest == 0,
+	    ("System call %s returning in a critical section",
+	    (code >= 0 && code < SYS_MAXSYSCALL) ? syscallnames[code] : "???"));
+	KASSERT(td->td_locks == 0,
+	    ("System call %s returning with %d locks held",
+	    (code >= 0 && code < SYS_MAXSYSCALL) ? syscallnames[code] : "???",
+	    td->td_locks));
+
+	/*
 	 * End of syscall tracing.
 	 */
 	CTR4(KTR_SYSC, "syscall exit thread %p pid %d proc %s code %d", td,
@@ -200,11 +211,6 @@ ia32_syscall(struct trapframe *tf)
 	STOPEVENT(p, S_SCX, code);
  
 	PTRACESTOP_SC(p, td, S_PT_SCX);
-
-	WITNESS_WARN(WARN_PANIC, NULL, "System call %s returning",
-	    (code >= 0 && code < SYS_MAXSYSCALL) ? syscallnames[code] : "???");
-	mtx_assert(&sched_lock, MA_NOTOWNED);
-	mtx_assert(&Giant, MA_NOTOWNED);
 }
 
 /*
diff --git a/sys/ia64/ia64/trap.c b/sys/ia64/ia64/trap.c
index 93b518d2790e..d0f3c9846614 100644
--- a/sys/ia64/ia64/trap.c
+++ b/sys/ia64/ia64/trap.c
@@ -85,9 +85,7 @@ static void break_syscall(struct trapframe *tf);
  */
 extern struct fpswa_iface *fpswa_iface;
 
-#ifdef WITNESS
 extern char *syscallnames[];
-#endif
 
 static const char *ia64_vector_names[] = {
 	"VHPT Translation",			/* 0 */
@@ -1049,6 +1047,19 @@ syscall(struct trapframe *tf)
 	}
 
 	/*
+	 * Check for misbehavior.
+	 */
+	WITNESS_WARN(WARN_PANIC, NULL, "System call %s returning",
+	    (code >= 0 && code < SYS_MAXSYSCALL) ? syscallnames[code] : "???");
+	KASSERT(td->td_critnest == 0,
+	    ("System call %s returning in a critical section",
+	    (code >= 0 && code < SYS_MAXSYSCALL) ? syscallnames[code] : "???"));
+	KASSERT(td->td_locks == 0,
+	    ("System call %s returning with %d locks held",
+	    (code >= 0 && code < SYS_MAXSYSCALL) ? syscallnames[code] : "???",
+	    td->td_locks));
+
+	/*
 	 * Handle reschedule and other end-of-syscall issues
 	 */
 	userret(td, tf);
@@ -1069,10 +1080,5 @@ syscall(struct trapframe *tf)
 
 	PTRACESTOP_SC(p, td, S_PT_SCX);
 
-	WITNESS_WARN(WARN_PANIC, NULL, "System call %s returning",
-	    (code >= 0 && code < SYS_MAXSYSCALL) ? syscallnames[code] : "???");
-	mtx_assert(&sched_lock, MA_NOTOWNED);
-	mtx_assert(&Giant, MA_NOTOWNED);
-
 	return (error);
 }
diff --git a/sys/powerpc/aim/trap.c b/sys/powerpc/aim/trap.c
index 527e9fb93b57..0f5961bbb269 100644
--- a/sys/powerpc/aim/trap.c
+++ b/sys/powerpc/aim/trap.c
@@ -470,6 +470,19 @@ syscall(struct trapframe *frame)
 	if ((callp->sy_narg & SYF_MPSAFE) == 0)
 		mtx_unlock(&Giant);
 
+	/*
+	 * Check for misbehavior.
+	 */
+	WITNESS_WARN(WARN_PANIC, NULL, "System call %s returning",
+	    (code >= 0 && code < SYS_MAXSYSCALL) ? syscallnames[code] : "???");
+	KASSERT(td->td_critnest == 0,
+	    ("System call %s returning in a critical section",
+	    (code >= 0 && code < SYS_MAXSYSCALL) ? syscallnames[code] : "???"));
+	KASSERT(td->td_locks == 0,
+	    ("System call %s returning with %d locks held",
+	    (code >= 0 && code < SYS_MAXSYSCALL) ? syscallnames[code] : "???",
+	    td->td_locks));
+
 #ifdef	KTRACE
 	if (KTRPOINT(td, KTR_SYSRET))
 		ktrsysret(code, error, td->td_retval[0]);
@@ -481,11 +494,6 @@ syscall(struct trapframe *frame)
 	STOPEVENT(p, S_SCX, code);
  
 	PTRACESTOP_SC(p, td, S_PT_SCX);
-
-	WITNESS_WARN(WARN_PANIC, NULL, "System call %s returning",
-	    (code >= 0 && code < SYS_MAXSYSCALL) ? syscallnames[code] : "???");
-	mtx_assert(&sched_lock, MA_NOTOWNED);
-	mtx_assert(&Giant, MA_NOTOWNED);
 }
 
 static int
diff --git a/sys/powerpc/powerpc/trap.c b/sys/powerpc/powerpc/trap.c
index 527e9fb93b57..0f5961bbb269 100644
--- a/sys/powerpc/powerpc/trap.c
+++ b/sys/powerpc/powerpc/trap.c
@@ -470,6 +470,19 @@ syscall(struct trapframe *frame)
 	if ((callp->sy_narg & SYF_MPSAFE) == 0)
 		mtx_unlock(&Giant);
 
+	/*
+	 * Check for misbehavior.
+	 */
+	WITNESS_WARN(WARN_PANIC, NULL, "System call %s returning",
+	    (code >= 0 && code < SYS_MAXSYSCALL) ? syscallnames[code] : "???");
+	KASSERT(td->td_critnest == 0,
+	    ("System call %s returning in a critical section",
+	    (code >= 0 && code < SYS_MAXSYSCALL) ? syscallnames[code] : "???"));
+	KASSERT(td->td_locks == 0,
+	    ("System call %s returning with %d locks held",
+	    (code >= 0 && code < SYS_MAXSYSCALL) ? syscallnames[code] : "???",
+	    td->td_locks));
+
 #ifdef	KTRACE
 	if (KTRPOINT(td, KTR_SYSRET))
 		ktrsysret(code, error, td->td_retval[0]);
@@ -481,11 +494,6 @@ syscall(struct trapframe *frame)
 	STOPEVENT(p, S_SCX, code);
  
 	PTRACESTOP_SC(p, td, S_PT_SCX);
-
-	WITNESS_WARN(WARN_PANIC, NULL, "System call %s returning",
-	    (code >= 0 && code < SYS_MAXSYSCALL) ? syscallnames[code] : "???");
-	mtx_assert(&sched_lock, MA_NOTOWNED);
-	mtx_assert(&Giant, MA_NOTOWNED);
 }
 
 static int
diff --git a/sys/sparc64/sparc64/trap.c b/sys/sparc64/sparc64/trap.c
index f45d273f532e..b1c0dcc202ee 100644
--- a/sys/sparc64/sparc64/trap.c
+++ b/sys/sparc64/sparc64/trap.c
@@ -648,6 +648,19 @@ syscall(struct trapframe *tf)
 		mtx_unlock(&Giant);
 
 	/*
+	 * Check for misbehavior.
+	 */
+	WITNESS_WARN(WARN_PANIC, NULL, "System call %s returning",
+	    (code >= 0 && code < SYS_MAXSYSCALL) ? syscallnames[code] : "???");
+	KASSERT(td->td_critnest == 0,
+	    ("System call %s returning in a critical section",
+	    (code >= 0 && code < SYS_MAXSYSCALL) ? syscallnames[code] : "???"));
+	KASSERT(td->td_locks == 0,
+	    ("System call %s returning with %d locks held",
+	    (code >= 0 && code < SYS_MAXSYSCALL) ? syscallnames[code] : "???",
+	    td->td_locks));
+
+	/*
 	 * Handle reschedule and other end-of-syscall issues
 	 */
 	userret(td, tf);
@@ -664,9 +677,4 @@ syscall(struct trapframe *tf)
 	STOPEVENT(p, S_SCX, code);
 
 	PTRACESTOP_SC(p, td, S_PT_SCX);
-
-	WITNESS_WARN(WARN_PANIC, NULL, "System call %s returning",
-	    (code >= 0 && code < SYS_MAXSYSCALL) ? syscallnames[code] : "???");
-	mtx_assert(&sched_lock, MA_NOTOWNED);
-	mtx_assert(&Giant, MA_NOTOWNED);
 }