Revert PAE pmap for now, until the strange bug is found. This stops

the freezes many of us are seeing (especially on amd64 machines running
OpenBSD/i386).

Much testing by nick@ (as always - thanks!), hugh@, ian@, kettenis@
and Sam Smith (s (at) msmith (dot) net).

Requested by, input from, and ok deraadt@  ok art@, kettenis@, miod@

2 files changed, 26 insertions, 57 deletions

diff --git a/lib/libkvm/kvm_i386.c b/lib/libkvm/kvm_i386.c
index e88444fcb71..815417c6c2d 100644
--- a/lib/libkvm/kvm_i386.c
+++ b/lib/libkvm/kvm_i386.c
@@ -1,4 +1,4 @@
-/*	$OpenBSD: kvm_i386.c,v 1.19 2006/06/09 09:46:04 mickey Exp $ */
+/*	$OpenBSD: kvm_i386.c,v 1.20 2007/02/20 21:15:00 tom Exp $ */
 /*	$NetBSD: kvm_i386.c,v 1.9 1996/03/18 22:33:38 thorpej Exp $	*/
 
 /*-
@@ -38,7 +38,7 @@
 #if 0
 static char sccsid[] = "@(#)kvm_hp300.c	8.1 (Berkeley) 6/4/93";
 #else
-static char *rcsid = "$OpenBSD: kvm_i386.c,v 1.19 2006/06/09 09:46:04 mickey Exp $";
+static char *rcsid = "$OpenBSD: kvm_i386.c,v 1.20 2007/02/20 21:15:00 tom Exp $";
 #endif
 #endif /* LIBC_SCCS and not lint */
 
@@ -68,21 +68,9 @@ static char *rcsid = "$OpenBSD: kvm_i386.c,v 1.19 2006/06/09 09:46:04 mickey Exp
 #include <machine/pte.h>
 
 struct vmstate {
-	void *PTD;
-	paddr_t pg_frame;
-	paddr_t pt_mask;
-	int size;
-	int pte_size;
+	pd_entry_t *PTD;
 };
 
-#define	pdei(vm,v)	((v) >> ((vm)->size == NBPG ? 22 : 21))
-#define	ptei(vm,v)	(((v) & (vm)->pt_mask) >> PGSHIFT)
-#define	PDE(vm,v)	\
-    ((vm)->size == NBPG ? ((u_int32_t *)(vm)->PTD)[pdei(vm,v)] : \
-    ((u_int64_t *)(vm)->PTD)[pdei(vm,v)])
-#define	PG_FRAME(vm)	((vm)->pg_frame)
-#define	pte_size(vm)	((vm)->pte_size)
-
 void
 _kvm_freevtop(kvm_t *kd)
 {
@@ -98,10 +86,9 @@ _kvm_freevtop(kvm_t *kd)
 int
 _kvm_initvtop(kvm_t *kd)
 {
-	struct nlist nl[3];
+	struct nlist nl[2];
 	struct vmstate *vm;
-	paddr_t pa;
-	int ps;
+	u_long pa;
 
 	vm = (struct vmstate *)_kvm_malloc(kd, sizeof(*vm));
 	if (vm == NULL)
@@ -111,48 +98,31 @@ _kvm_initvtop(kvm_t *kd)
 	vm->PTD = NULL;
 
 	nl[0].n_name = "_PTDpaddr";
-	nl[1].n_name = "_PTDsize";
-	nl[2].n_name = NULL;
+	nl[1].n_name = NULL;
 
 	if (kvm_nlist(kd, nl) != 0) {
 		_kvm_err(kd, kd->program, "bad namelist");
 		return (-1);
 	}
 
-	if (_kvm_pread(kd, kd->pmfd, &ps, sizeof ps,
-	    _kvm_pa2off(kd, nl[1].n_value - KERNBASE)) != sizeof ps)
-		return (-1);
+	if (_kvm_pread(kd, kd->pmfd, &pa, sizeof pa,
+	    (off_t)_kvm_pa2off(kd, nl[0].n_value - KERNBASE)) != sizeof pa)
+		goto invalid;
 
-	pa = 0;
-	if (ps == NBPG) {
-		vm->pg_frame = 0xfffff000;
-		vm->pt_mask = 0x003ff000;
-		vm->pte_size = 4;
-	} else if (ps == NBPG * 4) {
-		vm->pg_frame = 0xffffff000ULL;
-		vm->pt_mask = 0x001ff000;
-		vm->pte_size = 8;
-	} else {
-		_kvm_err(kd, 0, "PTDsize is invalid");
-		return (-1);
-	}
+	vm->PTD = (pd_entry_t *)_kvm_malloc(kd, NBPG);
 
-	if (_kvm_pread(kd, kd->pmfd, &pa, vm->pte_size,
-	    _kvm_pa2off(kd, nl[0].n_value - KERNBASE)) != vm->pte_size)
-		return (-1);
+	if (_kvm_pread(kd, kd->pmfd, vm->PTD, NBPG,
+	    (off_t)_kvm_pa2off(kd, pa)) != NBPG)
+		goto invalid;
 
-	vm->PTD = _kvm_malloc(kd, ps);
-	if (vm->PTD == NULL)
-		return (-1);
+	return (0);
 
-	if (_kvm_pread(kd, kd->pmfd, vm->PTD, ps, _kvm_pa2off(kd, pa)) != ps) {
+invalid:
+	if (vm->PTD != NULL) {
 		free(vm->PTD);
 		vm->PTD = NULL;
-		return (-1);
 	}
-
-	vm->size = ps;
-	return (0);
+	return (-1);
 }
 
 /*
@@ -161,9 +131,9 @@ _kvm_initvtop(kvm_t *kd)
 int
 _kvm_kvatop(kvm_t *kd, u_long va, paddr_t *pa)
 {
-	u_long offset;
+	u_long offset, pte_pa;
 	struct vmstate *vm;
-	paddr_t pte, pte_pa;
+	pt_entry_t pte;
 
 	if (!kd->vmst) {
 		_kvm_err(kd, 0, "vatop called before initvtop");
@@ -186,19 +156,18 @@ _kvm_kvatop(kvm_t *kd, u_long va, paddr_t *pa)
 		*pa = va;
 		return (NBPG - (int)offset);
 	}
-	if ((PDE(vm, va) & PG_V) == 0)
+	if ((vm->PTD[pdei(va)] & PG_V) == 0)
 		goto invalid;
 
-	pte_pa = (PDE(vm, va) & PG_FRAME(vm)) +
-	    (ptei(vm, va) * pte_size(vm));
+	pte_pa = (vm->PTD[pdei(va)] & PG_FRAME) +
+	    (ptei(va) * sizeof(pt_entry_t));
 
 	/* XXX READ PHYSICAL XXX */
-	pte = 0;
-	if (_kvm_pread(kd, kd->pmfd, &pte, pte_size(vm),
-	    _kvm_pa2off(kd, pte_pa)) != pte_size(vm))
+	if (_kvm_pread(kd, kd->pmfd, &pte, sizeof pte,
+	    (off_t)_kvm_pa2off(kd, pte_pa)) != sizeof pte)
 		goto invalid;
 
-	*pa = (pte & PG_FRAME(vm)) + offset;
+	*pa = (pte & PG_FRAME) + offset;
 	return (NBPG - (int)offset);
 
 invalid:
diff --git a/lib/libkvm/shlib_version b/lib/libkvm/shlib_version
index d0f0988b418..1c5d96eb2aa 100644
--- a/lib/libkvm/shlib_version
+++ b/lib/libkvm/shlib_version
@@ -1,2 +1,2 @@
-major=8
+major=9
 minor=0