Index: sys/arch/sparc/sparc/pmap.c
===================================================================
RCS file: /cvsroot/src/sys/arch/sparc/sparc/pmap.c,v
retrieving revision 1.365
diff -p -u -r1.365 pmap.c
--- sys/arch/sparc/sparc/pmap.c	3 Sep 2018 16:29:27 -0000	1.365
+++ sys/arch/sparc/sparc/pmap.c	13 Jan 2019 06:08:22 -0000
@@ -176,8 +176,13 @@ paddr_t	vm_first_phys = (paddr_t)-1;
 paddr_t	vm_last_phys = 0;
 psize_t vm_num_phys;
 
+#if 0
 #define	PMAP_LOCK()	KERNEL_LOCK(1, NULL)
 #define	PMAP_UNLOCK()	KERNEL_UNLOCK_ONE(NULL)
+#else
+#define	PMAP_LOCK()	mutex_enter(&pmap_lock)
+#define	PMAP_UNLOCK()	mutex_exit(&pmap_lock)
+#endif
 
 /*
  * Flags in pvlist.pv_flags.  Note that PV_MOD must be 1 and PV_REF must be 2
@@ -347,6 +352,7 @@ mmuq_insert_tail(struct mmuentry *head, 
 int	seginval;		/* [4/4c] the invalid segment number */
 int	reginval;		/* [4/3mmu] the invalid region number */
 
+static kmutex_t pmap_lock;
 static kmutex_t demap_lock;
 static bool	lock_available = false;	/* demap_lock has been initialized */
 
@@ -3070,6 +3076,7 @@ pmap_bootstrap(int nctx, int nregion, in
 	}
 
 	pmap_page_upload();
+	mutex_init(&pmap_lock, MUTEX_DEFAULT, IPL_NONE);
 	mutex_init(&demap_lock, MUTEX_DEFAULT, IPL_VM);
 	mutex_init(&ctx_lock, MUTEX_DEFAULT, IPL_SCHED);
 	lock_available = true;
@@ -4662,7 +4669,7 @@ pmap_remove(struct pmap *pm, vaddr_t va,
 	}
 
 	ctx = getcontext();
-	s = splvm();		/* XXX conservative */
+	s = splvm();
 	PMAP_LOCK();
 	for (; va < endva; va = nva) {
 		/* do one virtual segment at a time */
@@ -6022,7 +6029,7 @@ pmap_kenter_pa4_4c(vaddr_t va, paddr_t p
 	splx(s);
 }
 
-#if notyet
+#if notyet /* XXXMRG delete */
 void pmap_lockmmu(vaddr_t sva, size_t sz);
 
 void
@@ -6286,7 +6293,7 @@ pmap_enk4m(struct pmap *pm, vaddr_t va, 
 	sp = &rp->rg_segmap[vs];
 
 	kpreempt_disable();
-	s = splvm();		/* XXX way too conservative */
+	s = splvm();
 	PMAP_LOCK();
 
 	if (rp->rg_seg_ptps == NULL) /* enter new region */
@@ -6372,7 +6379,7 @@ pmap_enu4m(struct pmap *pm, vaddr_t va, 
 	vr = VA_VREG(va);
 	vs = VA_VSEG(va);
 	rp = &pm->pm_regmap[vr];
-	s = splvm();			/* XXX conservative */
+	s = splvm();
 	PMAP_LOCK();
 
 	if (rp->rg_segmap == NULL) {