Add support for logging to stderr or syslog, and to run vmd in

foreground with -d.

OK mlarkin@ jung@

8 files changed, 442 insertions, 194 deletions

diff --git a/usr.sbin/vmd/Makefile b/usr.sbin/vmd/Makefile
index c02a006cf10..6f720bff811 100644
--- a/usr.sbin/vmd/Makefile
+++ b/usr.sbin/vmd/Makefile
@@ -2,7 +2,7 @@
 .if ${MACHINE} == "amd64"
 
 PROG=	vmd
-SRCS=	vmd.c loadfile_elf.c pci.c virtio.c
+SRCS=	vmd.c loadfile_elf.c pci.c virtio.c log.c
 CFLAGS+= -Wall -I${.CURDIR}
 CFLAGS+= -Wstrict-prototypes -Wmissing-prototypes
 CFLAGS+= -Wmissing-declarations
diff --git a/usr.sbin/vmd/loadfile_elf.c b/usr.sbin/vmd/loadfile_elf.c
index df566c4f2db..29e88de556c 100644
--- a/usr.sbin/vmd/loadfile_elf.c
+++ b/usr.sbin/vmd/loadfile_elf.c
@@ -1,5 +1,5 @@
 /* $NetBSD: loadfile.c,v 1.10 2000/12/03 02:53:04 tsutsui Exp $ */
-/* $OpenBSD: loadfile_elf.c,v 1.1 2015/11/22 20:20:32 mlarkin Exp $ */
+/* $OpenBSD: loadfile_elf.c,v 1.2 2015/11/23 13:04:49 reyk Exp $ */
 
 /*-
  * Copyright (c) 1997 The NetBSD Foundation, Inc.
@@ -382,8 +382,7 @@ mread(int fd, uint32_t addr, size_t sz)
 			ct = sz;
 
 		if (read(fd, buf, ct) != ct) {
-			fprintf(stderr, "%s: error %d in mread (%s)\n\r",
-			    __progname, errno, strerror(errno));
+			log_warn("%s: error %d in mread", __progname, errno);
 			return (0);
 		}
 		rd += ct;
@@ -407,8 +406,7 @@ mread(int fd, uint32_t addr, size_t sz)
 			ct = PAGE_SIZE;
 
 		if (read(fd, buf, ct) != ct) {
-			fprintf(stderr, "%s: error %d in mread (%s)\n\r",
-			    __progname, errno, strerror(errno));
+			log_warn("%s: error %d in mread", __progname, errno);
 			return (0);
 		}
 		rd += ct;
@@ -534,8 +532,7 @@ mbzero(uint32_t addr, int sz)
 static void
 mbcopy(char *src, char *dst, int sz)
 {
-	fprintf(stderr, "warning: bcopy during ELF kernel load not "
-	    "supported\n\r");
+	log_warnx("warning: bcopy during ELF kernel load not supported");
 }
 
 /*
diff --git a/usr.sbin/vmd/log.c b/usr.sbin/vmd/log.c
new file mode 100644
index 00000000000..6991b963bd3
--- /dev/null
+++ b/usr.sbin/vmd/log.c
@@ -0,0 +1,206 @@
+/*	$OpenBSD: log.c,v 1.1 2015/11/23 13:04:49 reyk Exp $	*/
+
+/*
+ * Copyright (c) 2003, 2004 Henning Brauer <henning@openbsd.org>
+ *
+ * Permission to use, copy, modify, and distribute this software for any
+ * purpose with or without fee is hereby granted, provided that the above
+ * copyright notice and this permission notice appear in all copies.
+ *
+ * THE SOFTWARE IS PROVIDED "AS IS" AND THE AUTHOR DISCLAIMS ALL WARRANTIES
+ * WITH REGARD TO THIS SOFTWARE INCLUDING ALL IMPLIED WARRANTIES OF
+ * MERCHANTABILITY AND FITNESS. IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR
+ * ANY SPECIAL, DIRECT, INDIRECT, OR CONSEQUENTIAL DAMAGES OR ANY DAMAGES
+ * WHATSOEVER RESULTING FROM LOSS OF USE, DATA OR PROFITS, WHETHER IN AN
+ * ACTION OF CONTRACT, NEGLIGENCE OR OTHER TORTIOUS ACTION, ARISING OUT OF
+ * OR IN CONNECTION WITH THE USE OR PERFORMANCE OF THIS SOFTWARE.
+ */
+
+#include <stdio.h>
+#include <stdlib.h>
+#include <stdarg.h>
+#include <string.h>
+#include <syslog.h>
+#include <errno.h>
+#include <time.h>
+
+int		 debug;
+int		 verbose;
+const char	*log_procname;
+
+void	log_init(int, int);
+void	log_procinit(const char *);
+void	log_verbose(int);
+void	log_warn(const char *, ...)
+	    __attribute__((__format__ (printf, 1, 2)));
+void	log_warnx(const char *, ...)
+	    __attribute__((__format__ (printf, 1, 2)));
+void	log_info(const char *, ...)
+	    __attribute__((__format__ (printf, 1, 2)));
+void	log_debug(const char *, ...)
+	    __attribute__((__format__ (printf, 1, 2)));
+void	logit(int, const char *, ...)
+	    __attribute__((__format__ (printf, 2, 3)));
+void	vlog(int, const char *, va_list)
+	    __attribute__((__format__ (printf, 2, 0)));
+__dead void fatal(const char *, ...)
+	    __attribute__((__format__ (printf, 1, 2)));
+__dead void fatalx(const char *, ...)
+	    __attribute__((__format__ (printf, 1, 2)));
+
+void
+log_init(int n_debug, int facility)
+{
+	extern char	*__progname;
+
+	debug = n_debug;
+	verbose = n_debug;
+	log_procinit(__progname);
+
+	if (!debug)
+		openlog(__progname, LOG_PID | LOG_NDELAY, facility);
+
+	tzset();
+}
+
+void
+log_procinit(const char *procname)
+{
+	if (procname != NULL)
+		log_procname = procname;
+}
+
+void
+log_verbose(int v)
+{
+	verbose = v;
+}
+
+void
+logit(int pri, const char *fmt, ...)
+{
+	va_list	ap;
+
+	va_start(ap, fmt);
+	vlog(pri, fmt, ap);
+	va_end(ap);
+}
+
+void
+vlog(int pri, const char *fmt, va_list ap)
+{
+	char	*nfmt;
+
+	if (debug) {
+		/* best effort in out of mem situations */
+		if (asprintf(&nfmt, "%s\n", fmt) == -1) {
+			vfprintf(stderr, fmt, ap);
+			fprintf(stderr, "\n");
+		} else {
+			vfprintf(stderr, nfmt, ap);
+			free(nfmt);
+		}
+		fflush(stderr);
+	} else
+		vsyslog(pri, fmt, ap);
+}
+
+
+void
+log_warn(const char *emsg, ...)
+{
+	char	*nfmt;
+	va_list	 ap;
+
+	/* best effort to even work in out of memory situations */
+	if (emsg == NULL)
+		logit(LOG_CRIT, "%s", strerror(errno));
+	else {
+		va_start(ap, emsg);
+
+		if (asprintf(&nfmt, "%s: %s", emsg, strerror(errno)) == -1) {
+			/* we tried it... */
+			vlog(LOG_CRIT, emsg, ap);
+			logit(LOG_CRIT, "%s", strerror(errno));
+		} else {
+			vlog(LOG_CRIT, nfmt, ap);
+			free(nfmt);
+		}
+		va_end(ap);
+	}
+}
+
+void
+log_warnx(const char *emsg, ...)
+{
+	va_list	 ap;
+
+	va_start(ap, emsg);
+	vlog(LOG_CRIT, emsg, ap);
+	va_end(ap);
+}
+
+void
+log_info(const char *emsg, ...)
+{
+	va_list	 ap;
+
+	va_start(ap, emsg);
+	vlog(LOG_INFO, emsg, ap);
+	va_end(ap);
+}
+
+void
+log_debug(const char *emsg, ...)
+{
+	va_list	 ap;
+
+	if (verbose > 1) {
+		va_start(ap, emsg);
+		vlog(LOG_DEBUG, emsg, ap);
+		va_end(ap);
+	}
+}
+
+static void
+vfatal(const char *emsg, va_list ap)
+{
+	static char	s[BUFSIZ];
+	const char	*sep;
+
+	if (emsg != NULL) {
+		(void)vsnprintf(s, sizeof(s), emsg, ap);
+		sep = ": ";
+	} else {
+		s[0] = '\0';
+		sep = "";
+	}
+	if (errno)
+		logit(LOG_CRIT, "fatal in %s: %s%s%s",
+		    log_procname, s, sep, strerror(errno));
+	else
+		logit(LOG_CRIT, "fatal in %s%s%s", log_procname, sep, s);
+}
+
+void
+fatal(const char *emsg, ...)
+{
+	va_list	ap;
+
+	va_start(ap, emsg);
+	vfatal(emsg, ap);
+	va_end(ap);
+	exit(1);
+}
+
+void
+fatalx(const char *emsg, ...)
+{
+	va_list	ap;
+
+	errno = 0;
+	va_start(ap, emsg);
+	vfatal(emsg, ap);
+	va_end(ap);
+	exit(1);
+}
diff --git a/usr.sbin/vmd/pci.c b/usr.sbin/vmd/pci.c
index e0fd19384a5..c8ff945a8b4 100644
--- a/usr.sbin/vmd/pci.c
+++ b/usr.sbin/vmd/pci.c
@@ -1,4 +1,4 @@
-/*	$OpenBSD: pci.c,v 1.2 2015/11/22 21:51:32 reyk Exp $	*/
+/*	$OpenBSD: pci.c,v 1.3 2015/11/23 13:04:49 reyk Exp $	*/
 
 /*
  * Copyright (c) 2015 Mike Larkin <mlarkin@openbsd.org>
@@ -89,7 +89,7 @@ pci_add_bar(uint8_t id, uint32_t type, void *barfn, void *cookie)
 		pci.pci_next_io_bar += VMM_PCI_IO_BAR_SIZE;
 		pci.pci_devices[id].pd_barfunc[bar_ct] = barfn;
 		pci.pci_devices[id].pd_bar_cookie[bar_ct] = cookie;
-		dprintf("%s: adding pci bar cookie for dev %d bar %d = %p\n\r",
+		dprintf("%s: adding pci bar cookie for dev %d bar %d = %p",
 		    __progname, id, bar_ct, cookie);
 		pci.pci_devices[id].pd_bartype[bar_ct] = PCI_BAR_TYPE_IO;
 		pci.pci_devices[id].pd_barsize[bar_ct] = VMM_PCI_IO_BAR_SIZE;
@@ -150,7 +150,7 @@ pci_add_device(uint8_t *id, uint16_t vid, uint16_t pid, uint8_t class,
 		    pci_pic_irqs[pci.pci_next_pic_irq];
 		pci.pci_devices[*id].pd_int = 1;
 		pci.pci_next_pic_irq++;
-		dprintf("assigned irq %d to pci dev %d\n\r",
+		dprintf("assigned irq %d to pci dev %d",
 		    pci.pci_devices[*id].pd_irq, *id);
 	}
 
@@ -177,8 +177,7 @@ pci_init(void)
 	if (pci_add_device(&id, PCI_VENDOR_OPENBSD, PCI_PRODUCT_OPENBSD_PCHB,
 	    PCI_CLASS_BRIDGE, PCI_SUBCLASS_BRIDGE_HOST,
 	    PCI_VENDOR_OPENBSD, 0, 0, NULL)) {
-		fprintf(stderr, "%s: can't add PCI host bridge\n",
-		    __progname);
+		log_warnx("%s: can't add PCI host bridge", __progname);
 		return;
 	}
 }
@@ -238,11 +237,11 @@ pci_handle_io(struct vm_run_params *vrp)
 		    PCI_MAPREG_IO_ADDR(pci.pci_devices[l].pd_bar[k]),
 		    &vei->vei.vei_data, &intr,
 		    pci.pci_devices[l].pd_bar_cookie[k])) {
-			fprintf(stderr, "%s: pci i/o access function failed\n",
+			log_warnx("%s: pci i/o access function failed",
 			    __progname);
 		}
 	} else {
-		fprintf(stderr, "%s: no pci i/o function for reg 0x%llx\n",
+		log_warnx("%s: no pci i/o function for reg 0x%llx",
 		    __progname, (uint64_t)reg);
 	}
 
@@ -266,8 +265,8 @@ pci_handle_data_reg(struct vm_run_params *vrp)
 		/* if read, return FFs */
 		if (vei->vei.vei_dir == 1)
 			vei->vei.vei_data = 0xffffffff;
-		fprintf(stderr, "invalid address register during pci read: "
-		    "0x%llx\r\n", (uint64_t)pci.pci_addr_reg);
+		log_warnx("invalid address register during pci read: "
+		    "0x%llx", (uint64_t)pci.pci_addr_reg);
 		return;
 	}
 
@@ -280,8 +279,8 @@ pci_handle_data_reg(struct vm_run_params *vrp)
 	if (csfunc != NULL) {
 		ret = csfunc(vei->vei.vei_dir, (o / 4), &vei->vei.vei_data);
 		if (ret)
-			fprintf(stderr, "cfg space access function failed for "
-			    "pci device %d\n", d);
+			log_warnx("cfg space access function failed for "
+			    "pci device %d", d);
 		return;
 	}
 
diff --git a/usr.sbin/vmd/virtio.c b/usr.sbin/vmd/virtio.c
index 5a5381c0afa..1dfdbf52670 100644
--- a/usr.sbin/vmd/virtio.c
+++ b/usr.sbin/vmd/virtio.c
@@ -1,4 +1,4 @@
-/*	$OpenBSD: virtio.c,v 1.2 2015/11/22 21:51:32 reyk Exp $	*/
+/*	$OpenBSD: virtio.c,v 1.3 2015/11/23 13:04:49 reyk Exp $	*/
 
 /*
  * Copyright (c) 2015 Mike Larkin <mlarkin@openbsd.org>
@@ -65,10 +65,10 @@ vioblk_cmd_name(uint32_t type)
 static void
 dump_descriptor_chain(struct vring_desc *desc, int16_t dxx)
 {
-	fprintf(stderr, "descriptor chain @ %d\n\r", dxx);
+	log_debug("descriptor chain @ %d", dxx);
 	do {
-		fprintf(stderr, "desc @%d addr/len/flags/next = 0x%llx / 0x%x "
-		    "/ 0x%x / 0x%x\n\r",
+		log_debug("desc @%d addr/len/flags/next = 0x%llx / 0x%x "
+		    "/ 0x%x / 0x%x",
 		    dxx,
 		    desc[dxx].addr,
 		    desc[dxx].len,
@@ -77,8 +77,8 @@ dump_descriptor_chain(struct vring_desc *desc, int16_t dxx)
 		dxx = desc[dxx].next;
 	} while (desc[dxx].flags & VRING_DESC_F_NEXT);
 
-	fprintf(stderr, "desc @%d addr/len/flags/next = 0x%llx / 0x%x / 0x%x "
-	    "/ 0x%x\n\r",
+	log_debug("desc @%d addr/len/flags/next = 0x%llx / 0x%x / 0x%x "
+	    "/ 0x%x",
 	    dxx,
 	    desc[dxx].addr,
 	    desc[dxx].len,
@@ -181,7 +181,7 @@ viornd_notifyq(void)
 
 	buf = malloc(vr_sz);
 	if (buf == NULL) {
-		fprintf(stderr, "malloc error getting viornd ring\n\r");
+		log_warn("malloc error getting viornd ring");
 		return (0);
 	}
 
@@ -207,8 +207,8 @@ viornd_notifyq(void)
 		arc4random_buf(rnd_data, desc[avail->ring[avail->idx]].len);
 		if (write_page((uint32_t)(desc[avail->ring[avail->idx]].addr),
 		    rnd_data, desc[avail->ring[avail->idx]].len, 0)) {
-			fprintf(stderr, "viornd: can't write random data @ "
-			    "0x%llx\n\r",
+			log_warnx("viornd: can't write random data @ "
+			    "0x%llx",
 			    desc[avail->ring[avail->idx]].addr);
 		} else {
 			/* ret == 1 -> interrupt needed */
@@ -221,8 +221,7 @@ viornd_notifyq(void)
 			used->idx++;
 
 			if (push_virtio_ring(buf, q_gpa, vr_sz)) {
-				fprintf(stderr, "viornd: error writing vio "
-				    "ring\n\r");
+				log_warnx("viornd: error writing vio ring");
 			}
 			
 		}
@@ -245,7 +244,7 @@ virtio_rnd_io(int dir, uint16_t reg, uint32_t *data, uint8_t *intr,
 		case VIRTIO_CONFIG_DEVICE_FEATURES:
 		case VIRTIO_CONFIG_QUEUE_SIZE:
 		case VIRTIO_CONFIG_ISR_STATUS:
-			fprintf(stderr, "%s: illegal write %x to %s\n\r",
+			log_warnx("%s: illegal write %x to %s",
 			    __progname, *data, virtio_reg_name(reg));
 			break;
 		case VIRTIO_CONFIG_GUEST_FEATURES:
@@ -327,23 +326,20 @@ vioblk_do_read(struct vioblk_dev *dev, off_t sector, ssize_t sz)
 	char *buf;
 
 	buf = malloc(sz);
-
 	if (buf == NULL) {
-		fprintf(stderr, "malloc errror vioblk read\n\r");
+		log_warn("malloc errror vioblk read");
 		return (NULL);
 	}
 
 	if (lseek(dev->fd, sector * VIRTIO_BLK_SECTOR_SIZE,
 	    SEEK_SET) == -1) {
-		fprintf(stderr, "seek error in vioblk read: %d\n\r",
-		    errno);
+		log_warn("seek error in vioblk read");
 		free(buf);
 		return (NULL);
 	}
  
 	if (read(dev->fd, buf, sz) != sz) {
-		fprintf(stderr, "vioblk read error: %d\n\r",
-		    errno);
+		log_warn("vioblk read error");
 		free(buf);
 		return (NULL);
 	}
@@ -356,14 +352,12 @@ vioblk_do_write(struct vioblk_dev *dev, off_t sector, char *buf, ssize_t sz)
 {
 	if (lseek(dev->fd, sector * VIRTIO_BLK_SECTOR_SIZE,
 	    SEEK_SET) == -1) {
-		fprintf(stderr, "seek error in vioblk write: %d\n\r",
-		    errno);
+		log_warn("seek error in vioblk write");
 		return (1);
 	}
 
 	if (write(dev->fd, buf, sz) != sz) {
-		fprintf(stderr, "vioblk write error: %d\n\r",
-		    errno);
+		log_warn("vioblk write error");
 		free(buf);
 		return (1);
 	}
@@ -403,7 +397,7 @@ vioblk_notifyq(struct vioblk_dev *dev)
 
 	vr = malloc(vr_sz);
 	if (vr == NULL) {
-		fprintf(stderr, "malloc error getting vioblk ring\n\r");
+		log_warn("malloc error getting vioblk ring");
 		return (0);
 	}
 
@@ -411,7 +405,7 @@ vioblk_notifyq(struct vioblk_dev *dev)
 
 	for (i = 0; i < vr_sz; i += VIRTIO_PAGE_SIZE) {
 		if (read_page((uint32_t)q_gpa + i, vr + i, PAGE_SIZE, 0)) {
-			fprintf(stderr, "error reading gpa 0x%x\n\r",
+			log_warnx("error reading gpa 0x%x",
 			    (uint32_t)q_gpa + i);
 			free(vr);
 			return (0);
@@ -429,7 +423,7 @@ vioblk_notifyq(struct vioblk_dev *dev)
 	idx = dev->vq[dev->cfg.queue_notify].last_avail & VIOBLK_QUEUE_MASK;
 
 	if ((avail->idx & VIOBLK_QUEUE_MASK) == idx) {
-		fprintf(stderr, "vioblk queue notify - nothing to do?\n\r");
+		log_warnx("vioblk queue notify - nothing to do?");
 		free(vr);
 		return (0);
 	}
@@ -438,15 +432,15 @@ vioblk_notifyq(struct vioblk_dev *dev)
 	cmd_desc = &desc[cmd_desc_idx];
 
 	if ((cmd_desc->flags & VRING_DESC_F_NEXT) == 0) {
-		fprintf(stderr, "unchained vioblk cmd descriptor received "
-		    "(idx %d)\n\r", cmd_desc_idx);
+		log_warnx("unchained vioblk cmd descriptor received "
+		    "(idx %d)", cmd_desc_idx);
 		free(vr);
 		return (0);
 	}
 
 	/* Read command from descriptor ring */
 	if (read_page((uint32_t)cmd_desc->addr, &cmd, cmd_desc->len, 0)) {
-		fprintf(stderr, "vioblk: command read_page error @ 0x%llx\n\r",
+		log_warnx("vioblk: command read_page error @ 0x%llx",
 		    cmd_desc->addr);
 		free(vr);
 		return (0);
@@ -459,8 +453,8 @@ vioblk_notifyq(struct vioblk_dev *dev)
 		secdata_desc = &desc[secdata_desc_idx];
 
 		if ((secdata_desc->flags & VRING_DESC_F_NEXT) == 0) {
-			fprintf(stderr, "unchained vioblk data descriptor "
-			    "received (idx %d)\n\r", cmd_desc_idx);
+			log_warnx("unchained vioblk data descriptor "
+			    "received (idx %d)", cmd_desc_idx);
 			free(vr);
 			return (0);
 		}
@@ -475,8 +469,8 @@ vioblk_notifyq(struct vioblk_dev *dev)
 			secdata = vioblk_do_read(dev, cmd.sector + secbias,
 			    (ssize_t)secdata_desc->len);
 			if (secdata == NULL) {
-				fprintf(stderr, "vioblk: block read error, "
-				    "sector %lld\n\r", cmd.sector);
+				log_warnx("vioblk: block read error, "
+				    "sector %lld", cmd.sector);
 				free(vr);
 				return (0);
 			}
@@ -490,8 +484,8 @@ vioblk_notifyq(struct vioblk_dev *dev)
 
 				if (write_page((uint32_t)secdata_desc->addr + j,
 				    secdata + j, len, 0)) {
-					fprintf(stderr, "can't write sector "
-					    "data to gpa @ 0x%llx\n\r",
+					log_warnx("can't write sector "
+					    "data to gpa @ 0x%llx",
 					    secdata_desc->addr);
 					dump_descriptor_chain(desc, cmd_desc_idx);
 					free(vr);
@@ -516,8 +510,8 @@ vioblk_notifyq(struct vioblk_dev *dev)
 		ds = VIRTIO_BLK_S_OK;
 		if (write_page((uint32_t)ds_desc->addr,
 		    &ds, ds_desc->len, 0)) {
-			fprintf(stderr, "can't write device status data @ "
-			    "0x%llx\n\r", ds_desc->addr);
+			log_warnx("can't write device status data @ "
+			    "0x%llx", ds_desc->addr);
 			dump_descriptor_chain(desc, cmd_desc_idx);
 			free(vr);
 			return (0);
@@ -534,7 +528,7 @@ vioblk_notifyq(struct vioblk_dev *dev)
 		    VIOBLK_QUEUE_MASK;
 
 		if (push_virtio_ring(vr, q_gpa, vr_sz)) {
-			fprintf(stderr, "vioblk: error writing vio ring\n\r");
+			log_warnx("vioblk: error writing vio ring");
 		}
 		break;
 	case VIRTIO_BLK_T_OUT:
@@ -542,15 +536,15 @@ vioblk_notifyq(struct vioblk_dev *dev)
 		secdata_desc = &desc[secdata_desc_idx];
 
 		if ((secdata_desc->flags & VRING_DESC_F_NEXT) == 0) {
-			fprintf(stderr, "wr vioblk: unchained vioblk data "
-			   "descriptor received (idx %d)\n\r", cmd_desc_idx);
+			log_warnx("wr vioblk: unchained vioblk data "
+			   "descriptor received (idx %d)", cmd_desc_idx);
 			free(vr);
 			return (0);
 		}
 
 		secdata = malloc(MAXPHYS);
 		if (secdata == NULL) {
-			fprintf(stderr, "wr vioblk: malloc error, len %d\n\r",
+			log_warn("wr vioblk: malloc error, len %d",
 			    secdata_desc->len);
 			free(vr);
 			return (0);
@@ -566,8 +560,8 @@ vioblk_notifyq(struct vioblk_dev *dev)
 					len = secdata_desc->len - j;
 				if (read_page((uint32_t)secdata_desc->addr + j,
 				    secdata + j, len, 0)) {
-					fprintf(stderr, "wr vioblk: can't read "
-					    "sector data @ 0x%llx\n\r",
+					log_warnx("wr vioblk: can't read "
+					    "sector data @ 0x%llx",
 					    secdata_desc->addr);
 					dump_descriptor_chain(desc,
 					     cmd_desc_idx);
@@ -581,8 +575,7 @@ vioblk_notifyq(struct vioblk_dev *dev)
 
 			if (vioblk_do_write(dev, cmd.sector + secbias,
 			    secdata, (ssize_t)secdata_desc->len)) {
-				fprintf(stderr, "wr vioblk: disk write "
-				    "error\n\r");
+				log_warnx("wr vioblk: disk write error");
 				free(vr);
 				free(secdata);
 				return (0);
@@ -603,8 +596,8 @@ vioblk_notifyq(struct vioblk_dev *dev)
 		ds = VIRTIO_BLK_S_OK;
 		if (write_page((uint32_t)ds_desc->addr,
 		    &ds, ds_desc->len, 0)) {
-			fprintf(stderr, "wr vioblk: can't write device status "
-			    "data @ 0x%llx\n\r", ds_desc->addr);
+			log_warnx("wr vioblk: can't write device status "
+			    "data @ 0x%llx", ds_desc->addr);
 			dump_descriptor_chain(desc, cmd_desc_idx);
 			free(vr);
 			return (0);
@@ -619,7 +612,7 @@ vioblk_notifyq(struct vioblk_dev *dev)
 		dev->vq[dev->cfg.queue_notify].last_avail = avail->idx &
 		    VIOBLK_QUEUE_MASK;
 		if (push_virtio_ring(vr, q_gpa, vr_sz))
-			fprintf(stderr, "wr vioblk: error writing vio ring\n\r");
+			log_warnx("wr vioblk: error writing vio ring");
 		break;
 	case VIRTIO_BLK_T_FLUSH:
 	case VIRTIO_BLK_T_FLUSH_OUT:
@@ -629,8 +622,8 @@ vioblk_notifyq(struct vioblk_dev *dev)
 		ds = VIRTIO_BLK_S_OK;
 		if (write_page((uint32_t)ds_desc->addr,
 		    &ds, ds_desc->len, 0)) {
-			fprintf(stderr, "fl vioblk: can't write device status "
-			    "data @ 0x%llx\n\r", ds_desc->addr);
+			log_warnx("fl vioblk: can't write device status "
+			    "data @ 0x%llx", ds_desc->addr);
 			dump_descriptor_chain(desc, cmd_desc_idx);
 			free(vr);
 			return (0);
@@ -645,7 +638,7 @@ vioblk_notifyq(struct vioblk_dev *dev)
 		dev->vq[dev->cfg.queue_notify].last_avail = avail->idx &
 		    VIOBLK_QUEUE_MASK;
 		if (push_virtio_ring(vr, q_gpa, vr_sz)) {
-			fprintf(stderr, "fl vioblk: error writing vio ring\n\r");
+			log_warnx("fl vioblk: error writing vio ring");
 		}
 		break;
 	}
@@ -668,7 +661,7 @@ virtio_blk_io(int dir, uint16_t reg, uint32_t *data, uint8_t *intr,
 		case VIRTIO_CONFIG_DEVICE_FEATURES:
 		case VIRTIO_CONFIG_QUEUE_SIZE:
 		case VIRTIO_CONFIG_ISR_STATUS:
-			fprintf(stderr, "%s: illegal write %x to %s\n\r",
+			log_warnx("%s: illegal write %x to %s",
 			    __progname, *data, virtio_reg_name(reg));
 			break;
 		case VIRTIO_CONFIG_GUEST_FEATURES:
@@ -743,7 +736,7 @@ virtio_net_io(int dir, uint16_t reg, uint32_t *data, uint8_t *intr,
 		case VIRTIO_CONFIG_DEVICE_FEATURES:
 		case VIRTIO_CONFIG_QUEUE_SIZE:
 		case VIRTIO_CONFIG_ISR_STATUS:
-			fprintf(stderr, "%s: illegal write %x to %s\n\r",
+			log_warnx("%s: illegal write %x to %s",
 			    __progname, *data, virtio_reg_name(reg));
 			break;
 		case VIRTIO_CONFIG_GUEST_FEATURES:
@@ -850,7 +843,7 @@ vionet_enq_rx(struct vionet_dev *dev, char *pkt, ssize_t sz, int *spc)
 
 	vr = malloc(vr_sz);
 	if (vr == NULL) {
-		fprintf(stderr, "rx enq :malloc error getting vionet ring\n\r");
+		log_warn("rx enq: malloc error getting vionet ring");
 		return (0);
 	}
 
@@ -858,7 +851,7 @@ vionet_enq_rx(struct vionet_dev *dev, char *pkt, ssize_t sz, int *spc)
 
 	for (i = 0; i < vr_sz; i += VIRTIO_PAGE_SIZE) {
 		if (read_page((uint32_t)q_gpa + i, vr + i, PAGE_SIZE, 0)) {
-			fprintf(stderr, "rx enq: error reading gpa 0x%x\n\r",
+			log_warnx("rx enq: error reading gpa 0x%x",
 			    (uint32_t)q_gpa + i);
 			free(vr);
 			return (0);
@@ -875,8 +868,7 @@ vionet_enq_rx(struct vionet_dev *dev, char *pkt, ssize_t sz, int *spc)
 	idx = dev->vq[0].last_avail & VIONET_QUEUE_MASK;
 
 	if ((avail->idx & VIONET_QUEUE_MASK) == idx) {
-		fprintf(stderr, "vionet queue notify - no space, dropping "
-		    "packet\n\r");
+		log_warnx("vionet queue notify - no space, dropping packet");
 		free(vr);
 		return (0);
 	}
@@ -889,7 +881,7 @@ vionet_enq_rx(struct vionet_dev *dev, char *pkt, ssize_t sz, int *spc)
 
 	/* must be not readable */
 	if ((pkt_desc->flags & VRING_DESC_F_WRITE) == 0) {
-		fprintf(stderr, "unexpected readable rx descriptor %d\n\r",
+		log_warnx("unexpected readable rx descriptor %d",
 		    pkt_desc_idx);
 		free(vr);
 		return (0);
@@ -897,8 +889,8 @@ vionet_enq_rx(struct vionet_dev *dev, char *pkt, ssize_t sz, int *spc)
 
 	/* Write packet to descriptor ring */
 	if (write_page((uint32_t)pkt_desc->addr, pkt, sz, 0)) {
-		fprintf(stderr, "vionet: rx enq packet write_page error @ "
-		    "0x%llx\n\r", pkt_desc->addr);
+		log_warnx("vionet: rx enq packet write_page error @ "
+		    "0x%llx", pkt_desc->addr);
 		free(vr);
 		return (0);
 	}
@@ -911,7 +903,7 @@ vionet_enq_rx(struct vionet_dev *dev, char *pkt, ssize_t sz, int *spc)
 	dev->vq[0].last_avail = (dev->vq[0].last_avail + 1);
 	*spc = avail->idx - dev->vq[0].last_avail;
 	if (push_virtio_ring(vr, q_gpa, vr_sz)) {
-		fprintf(stderr, "vionet: error writing vio ring\n\r");
+		log_warnx("vionet: error writing vio ring");
 	}
 
 	free(vr);
@@ -947,8 +939,7 @@ vionet_process_rx(void)
 					num_enq += vionet_enq_rx(&vionet[i],
 					    buf, sz, &spc);
 				} else if (sz == 0) {
-					fprintf(stderr, "process_rx: no data"
-					    "\n\r");
+					log_debug("process_rx: no data");
 					hasdata = 0;
 				}
 			}
@@ -981,7 +972,7 @@ vionet_notify_rx(struct vionet_dev *dev)
 
 	vr = malloc(vr_sz);
 	if (vr == NULL) {
-		fprintf(stderr, "malloc error getting vionet ring\n\r");
+		log_warn("malloc error getting vionet ring");
 		return;
 	}
 
@@ -989,7 +980,7 @@ vionet_notify_rx(struct vionet_dev *dev)
 
 	for (i = 0; i < vr_sz; i += VIRTIO_PAGE_SIZE) {
 		if (read_page((uint32_t)q_gpa + i, vr + i, PAGE_SIZE, 0)) {
-			fprintf(stderr, "error reading gpa 0x%x\n\r",
+			log_warnx("error reading gpa 0x%x",
 			    (uint32_t)q_gpa + i);
 			free(vr);
 			return;
@@ -1045,7 +1036,7 @@ vionet_notifyq(struct vionet_dev *dev)
 
 	vr = malloc(vr_sz);
 	if (vr == NULL) {
-		fprintf(stderr, "malloc error getting vionet ring\n\r");
+		log_warn("malloc error getting vionet ring");
 		return (0);
 	}
 
@@ -1053,7 +1044,7 @@ vionet_notifyq(struct vionet_dev *dev)
 
 	for (i = 0; i < vr_sz; i += VIRTIO_PAGE_SIZE) {
 		if (read_page((uint32_t)q_gpa + i, vr + i, PAGE_SIZE, 0)) {
-			fprintf(stderr, "error reading gpa 0x%x\n\r",
+			log_warnx("error reading gpa 0x%x",
 			    (uint32_t)q_gpa + i);
 			free(vr);
 			return (0);
@@ -1072,7 +1063,7 @@ vionet_notifyq(struct vionet_dev *dev)
 	idx = dev->vq[dev->cfg.queue_notify].last_avail & VIONET_QUEUE_MASK;
 
 	if ((avail->idx & VIONET_QUEUE_MASK) == idx) {
-		fprintf(stderr, "vionet tx queue notify - nothing to do?\n\r");
+		log_warnx("vionet tx queue notify - nothing to do?");
 		free(vr);
 		return (0);
 	}
@@ -1101,7 +1092,7 @@ vionet_notifyq(struct vionet_dev *dev)
 		 */
 		pkt = malloc(pktsz);
 		if (pkt == NULL) {
-			fprintf(stderr, "malloc error alloc packet buf\n\r");
+			log_warn("malloc error alloc packet buf");
 			free(vr);
 			return (0);
 		}
@@ -1113,8 +1104,8 @@ vionet_notifyq(struct vionet_dev *dev)
 		while (pkt_desc->flags & VRING_DESC_F_NEXT) {
 			/* must be not writable */
 			if (pkt_desc->flags & VRING_DESC_F_WRITE) {
-				fprintf(stderr, "unexpceted writable tx desc "
-				    "%d\n\r", pkt_desc_idx);
+				log_warnx("unexpceted writable tx desc "
+				    "%d", pkt_desc_idx);
 				free(vr);
 				return (0);
 			}
@@ -1122,8 +1113,8 @@ vionet_notifyq(struct vionet_dev *dev)
 			/* Read packet from descriptor ring */
 			if (read_page((uint32_t)pkt_desc->addr, pkt + ofs,
 			    pkt_desc->len, 0)) {
-				fprintf(stderr, "vionet: packet read_page error "
-				    "@ 0x%llx\n\r", pkt_desc->addr);
+				log_warnx("vionet: packet read_page error "
+				    "@ 0x%llx", pkt_desc->addr);
 				free(pkt);
 				free(vr);
 				return (0);
@@ -1136,8 +1127,8 @@ vionet_notifyq(struct vionet_dev *dev)
 
 		/* Now handle tail descriptor - must be not writable */
 		if (pkt_desc->flags & VRING_DESC_F_WRITE) {
-			fprintf(stderr, "unexpceted writable tx descriptor %d"
-			    "\n\r", pkt_desc_idx);
+			log_warnx("unexpceted writable tx descriptor %d",
+			    pkt_desc_idx);
 			free(vr);
 			return (0);
 		}
@@ -1145,8 +1136,8 @@ vionet_notifyq(struct vionet_dev *dev)
 		/* Read packet from descriptor ring */
 		if (read_page((uint32_t)pkt_desc->addr, pkt + ofs,
 		    pkt_desc->len, 0)) {
-			fprintf(stderr, "vionet: packet read_page error @ "
-			    "0x%llx\n\r", pkt_desc->addr);
+			log_warnx("vionet: packet read_page error @ "
+			    "0x%llx", pkt_desc->addr);
 			free(pkt);
 			free(vr);
 			return (0);
@@ -1154,8 +1145,8 @@ vionet_notifyq(struct vionet_dev *dev)
 
 		/* XXX signed vs unsigned here, funky cast */
 		if (write(dev->fd, pkt, pktsz) != (int)pktsz) {
-			fprintf(stderr, "vionet: tx failed writing to tap: "
-			    "%d\n\r", errno);
+			log_warnx("vionet: tx failed writing to tap: "
+			    "%d", errno);
 			free(pkt);
 			free(vr);
 			return (0);
@@ -1176,7 +1167,7 @@ vionet_notifyq(struct vionet_dev *dev)
 	}
 
 	if (push_virtio_ring(vr, q_gpa, vr_sz)) {
-		fprintf(stderr, "vionet: tx error writing vio ring\n\r");
+		log_warnx("vionet: tx error writing vio ring");
 	}
 
 	free(vr);
@@ -1198,13 +1189,13 @@ virtio_init(struct vm_create_params *vcp, int *child_disks, int *child_taps)
 	    PCI_SUBCLASS_SYSTEM_MISC,
 	    PCI_VENDOR_OPENBSD,
 	    PCI_PRODUCT_VIRTIO_ENTROPY, 1, NULL)) {
-		fprintf(stderr, "%s: can't add PCI virtio rng device\n",
+		log_warnx("%s: can't add PCI virtio rng device",
 		    __progname);
 		return;
 	}
 
 	if (pci_add_bar(id, PCI_MAPREG_TYPE_IO, virtio_rnd_io, NULL)) {
-		fprintf(stderr, "%s: can't add bar for virtio rng device\n",
+		log_warnx("%s: can't add bar for virtio rng device",
 		    __progname);
 		return;
 	}
@@ -1220,7 +1211,7 @@ virtio_init(struct vm_create_params *vcp, int *child_disks, int *child_taps)
 
 	vioblk = malloc(sizeof(struct vioblk_dev) * vcp->vcp_ndisks);
 	if (vioblk == NULL) {
-		fprintf(stderr, "%s: malloc failure allocating vioblks\n",
+		log_warn("%s: malloc failure allocating vioblks",
 		    __progname);
 		return;
 	}
@@ -1237,14 +1228,14 @@ virtio_init(struct vm_create_params *vcp, int *child_disks, int *child_taps)
 		    PCI_SUBCLASS_MASS_STORAGE_SCSI,
 		    PCI_VENDOR_OPENBSD,
 		    PCI_PRODUCT_VIRTIO_BLOCK, 1, NULL)) {
-			fprintf(stderr, "%s: can't add PCI virtio block "
-			    "device\n", __progname);
+			log_warnx("%s: can't add PCI virtio block "
+			    "device", __progname);
 			return;
 		}
 		if (pci_add_bar(id, PCI_MAPREG_TYPE_IO, virtio_blk_io,
 		    &vioblk[i])) {
-			fprintf(stderr, "%s: can't add bar for virtio block "
-			    "device\n", __progname);
+			log_warnx("%s: can't add bar for virtio block "
+			    "device", __progname);
 			return;
 		}
 		vioblk[i].vq[0].qs = VIOBLK_QUEUE_SIZE;
@@ -1260,7 +1251,7 @@ virtio_init(struct vm_create_params *vcp, int *child_disks, int *child_taps)
 
 	vionet = malloc(sizeof(struct vionet_dev) * vcp->vcp_nnics);
 	if (vionet == NULL) {
-		fprintf(stderr, "%s: malloc failure allocating vionets\n",
+		log_warn("%s: malloc failure allocating vionets",
 		    __progname);
 		return;
 	}
@@ -1275,15 +1266,15 @@ virtio_init(struct vm_create_params *vcp, int *child_disks, int *child_taps)
 		    PCI_SUBCLASS_SYSTEM_MISC,
 		    PCI_VENDOR_OPENBSD,
 		    PCI_PRODUCT_VIRTIO_NETWORK, 1, NULL)) {
-			fprintf(stderr, "%s: can't add PCI virtio net device\n",
+			log_warnx("%s: can't add PCI virtio net device",
 			    __progname);
 			return;
 		}
 
 		if (pci_add_bar(id, PCI_MAPREG_TYPE_IO, virtio_net_io,
 		    &vionet[i])) {
-			fprintf(stderr, "%s: can't add bar for virtio net "
-			    "device\n", __progname);
+			log_warnx("%s: can't add bar for virtio net "
+			    "device", __progname);
 			return;
 		}
 
diff --git a/usr.sbin/vmd/vmd.8 b/usr.sbin/vmd/vmd.8
index bf838516d60..367a12734a1 100644
--- a/usr.sbin/vmd/vmd.8
+++ b/usr.sbin/vmd/vmd.8
@@ -1,4 +1,4 @@
-.\"	$OpenBSD: vmd.8,v 1.2 2015/11/22 21:24:48 jmc Exp $
+.\"	$OpenBSD: vmd.8,v 1.3 2015/11/23 13:04:49 reyk Exp $
 .\"
 .\" Copyright (c) 2015 Mike Larkin <mlarkin@openbsd.org>
 .\"
@@ -14,7 +14,7 @@
 .\" ACTION OF CONTRACT, NEGLIGENCE OR OTHER TORTIOUS ACTION, ARISING OUT OF
 .\" OR IN CONNECTION WITH THE USE OR PERFORMANCE OF THIS SOFTWARE.
 .\"
-.Dd $Mdocdate: November 22 2015 $
+.Dd $Mdocdate: November 23 2015 $
 .Dt VMD 8
 .Os
 .Sh NAME
@@ -22,7 +22,7 @@
 .Nd virtual machine daemon
 .Sh SYNOPSIS
 .Nm vmd
-.Op Fl f Ar file
+.Op Fl dv
 .Sh DESCRIPTION
 .Nm
 is a daemon responsible for the execution of virtual machines (VMs) on a
@@ -55,6 +55,18 @@ is also responsible for proxying various other commands/requests from
 such as stopping VMs, and retrieving information from
 .Xr vmm 4
 about running VMs.
+.Pp
+The options are as follows:
+.Bl -tag -width Dssmacro=value
+.It Fl d
+Do not daemonize and log to
+.Em stderr .
+.It Fl v
+Verbose mode.
+Multiple
+.Fl v
+options increases the verbosity.
+.El
 .Sh SEE ALSO
 .Xr vmm 4 ,
 .Xr rc.conf 8 ,
diff --git a/usr.sbin/vmd/vmd.c b/usr.sbin/vmd/vmd.c
index b51eafb1795..e6c773d270e 100644
--- a/usr.sbin/vmd/vmd.c
+++ b/usr.sbin/vmd/vmd.c
@@ -1,4 +1,4 @@
-/*	$OpenBSD: vmd.c,v 1.3 2015/11/22 22:29:48 deraadt Exp $	*/
+/*	$OpenBSD: vmd.c,v 1.4 2015/11/23 13:04:49 reyk Exp $	*/
 
 /*
  * Copyright (c) 2015 Mike Larkin <mlarkin@openbsd.org>
@@ -39,7 +39,6 @@
 #include <machine/param.h>
 #include <machine/vmmvar.h>
 
-#include <err.h>
 #include <errno.h>
 #include <fcntl.h>
 #include <imsg.h>
@@ -51,6 +50,7 @@
 #include <stdio.h>
 #include <stdlib.h>
 #include <string.h>
+#include <syslog.h>
 #include <termios.h>
 #include <unistd.h>
 #include <util.h>
@@ -112,6 +112,8 @@ struct ns8250_regs {
 struct i8253_counter i8253_counter[3];
 struct ns8250_regs com1_regs;
 
+__dead void usage(void);
+
 void sighdlr(int);
 int main(int, char **);
 int control_run(void);
@@ -171,15 +173,39 @@ sighdlr(int sig)
 	}
 }
 
+__dead void
+usage(void)
+{
+	extern char *__progname;
+	fprintf(stderr, "usage: %s [-dv]", __progname);
+	exit(1);
+}
+
 int
 main(int argc, char **argv)
 {
-	int res;
+	int debug = 0, verbose = 0, c, res;
+
+	while ((c = getopt(argc, argv, "dv")) != -1) {
+		switch (c) {
+		case 'd':
+			debug = 2;
+			break;
+		case 'v':
+			verbose++;
+			break;
+		default:
+			usage();
+		}
+	}
+
+	/* log to stderr until daemonized */
+	log_init(debug ? debug : 1, LOG_DAEMON);
 
 	/* Open /dev/vmm */
 	vmm_fd = open(VMM_NODE, O_RDONLY);
 	if (vmm_fd == -1)
-		errx(1, "can't open vmm device node %s", VMM_NODE);
+		fatal("can't open vmm device node %s", VMM_NODE);
 
 	setproctitle("control");
 
@@ -189,13 +215,17 @@ main(int argc, char **argv)
 	signal(SIGINT, sighdlr);
 	signal(SIGCHLD, sighdlr);
 
-	if (daemon(0, 1) == -1)
-		errx(1, "can't daemonize\n");
+	log_init(debug, LOG_DAEMON);
+	log_verbose(verbose);
+	log_procinit("control");
+
+	if (!debug && daemon(1, 0) == -1)
+		fatal("can't daemonize");
 
 	res = control_run();
 
 	if (res == -1)
-		errx(1, "control socket error\n");
+		fatalx("control socket error");
 
 	return (0);
 }
@@ -225,7 +255,7 @@ control_run(void)
 	/* Establish and start listening on control socket */
 	socketpath = SOCKET_NAME;
 	if ((fd = socket(AF_UNIX, SOCK_STREAM | SOCK_CLOEXEC, 0)) == -1) {
-		fprintf(stderr, "%s: socket error\n", __progname);
+		log_warn("%s: socket error", __progname);
 		return (-1);
 	}
 
@@ -233,14 +263,14 @@ control_run(void)
 	sun.sun_family = AF_UNIX;
 	if (strlcpy(sun.sun_path, socketpath, sizeof(sun.sun_path)) >=
 	    sizeof(sun.sun_path)) {
-		fprintf(stderr, "%s: socket name too long\n", __progname);
+		log_warnx("%s: socket name too long", __progname);
 		close(fd);
 		return (-1);
 	}
 
 	if (unlink(socketpath) == -1)
 		if (errno != ENOENT) {
-			fprintf(stderr, "%s: unlink of %s failed\n",
+			log_warn("%s: unlink of %s failed",
 			    __progname, socketpath);
 			close(fd);
 			return (-1);
@@ -250,7 +280,7 @@ control_run(void)
 	mode = S_IRUSR|S_IWUSR|S_IRGRP|S_IWGRP;
 
 	if (bind(fd, (struct sockaddr *)&sun, sizeof(sun)) == -1) {
-		fprintf(stderr, "%s: control_init: bind of %s failed\n",
+		log_warn("%s: control_init: bind of %s failed",
 		    __progname, socketpath);
 		close(fd);
 		umask(old_umask);
@@ -260,7 +290,7 @@ control_run(void)
 	umask(old_umask);
 
 	if (chmod(socketpath, mode) == -1) {
-		fprintf(stderr, "%s: control_init: chmod of %s failed\n",
+		log_warn("%s: control_init: chmod of %s failed",
 		    __progname, socketpath);
 		close(fd);
 		unlink(socketpath);
@@ -268,14 +298,14 @@ control_run(void)
 	}
 
 	if ((ibuf = malloc(sizeof(struct imsgbuf))) == NULL) {
-		fprintf(stderr, "%s: out of memory\n", __progname);
+		log_warn("%s: out of memory", __progname);
 		close(fd);
 		unlink(socketpath);
 		return (-1);
 	}
 
 	if (listen(fd, NR_BACKLOG) == -1) {
-		fprintf(stderr, "%s: listen failed\n", __progname);
+		log_warn("%s: listen failed", __progname);
 		close(fd);
 		unlink(socketpath);
 		return (-1);
@@ -284,7 +314,7 @@ control_run(void)
 	while (!quit) {
 		if ((connfd = accept4(fd, (struct sockaddr *)&c_sun, &len,
 		    SOCK_CLOEXEC)) == -1) {
-			fprintf(stderr, "%s: accept4 error\n", __progname);
+			log_warn("%s: accept4 error", __progname);
 			close(fd);
 			unlink(socketpath);
 			return (-1);
@@ -292,7 +322,7 @@ control_run(void)
 			
 		imsg_init(ibuf, connfd);
 		if ((n = imsg_read(ibuf)) == -1 || n == 0) {
-			fprintf(stderr, "%s: imsg_read error, n=%d\n",
+			log_warnx("%s: imsg_read error, n=%d",
 			    __progname, n);
 			continue;
 		}
@@ -341,9 +371,8 @@ control_run(void)
 			while (ibuf->w.queued)
 				if (msgbuf_write(&ibuf->w) <= 0 && errno !=
 				    EAGAIN) {
-					fprintf(stderr, "%s: msgbuf_write "
-					    "error %d\n", __progname,
-					    errno);
+					log_warn("%s: msgbuf_write error",
+					    __progname);
 					close(fd);
 					close(connfd);
 					unlink(socketpath);
@@ -505,8 +534,8 @@ start_vm(struct imsg *imsg)
 		child_disks[i] = open(vcp->vcp_disks[i], O_RDWR);
 		if (child_disks[i] == -1) {
 			ret = errno;
-			fprintf(stderr, "%s: can't open %s (%d)\n", __progname,
-			    vcp->vcp_disks[i], errno);
+			log_warn("%s: can't open %s", __progname,
+			    vcp->vcp_disks[i]);
 			goto err;
 		}
 	}
@@ -514,8 +543,8 @@ start_vm(struct imsg *imsg)
 	bzero(&sb, sizeof(sb));
 	if (stat(vcp->vcp_kernel, &sb) == -1) {
 		ret = errno;
-		fprintf(stderr, "%s: can't stat kernel image %s (%d)\n",
-		    __progname, vcp->vcp_kernel, errno);
+		log_warn("%s: can't stat kernel image %s",
+		    __progname, vcp->vcp_kernel);
 		goto err;
 	}
 
@@ -525,22 +554,20 @@ start_vm(struct imsg *imsg)
 	kernel_fd = open(vcp->vcp_kernel, O_RDONLY);
 	if (kernel_fd == -1) {
 		ret = errno;
-		fprintf(stderr, "%s: can't open kernel image %s (%d)\n",
-		    __progname, vcp->vcp_kernel, errno);
+		log_warn("%s: can't open kernel image %s",
+		    __progname, vcp->vcp_kernel);
 		goto err;	
 	}
 
 	if (openpty(&ttym_fd, &ttys_fd, ptyn, NULL, NULL) == -1) {
 		ret = errno;
-		fprintf(stderr, "%s: openpty failed: %d\n",
-		    __progname, errno);
+		log_warn("%s: openpty failed", __progname);
 		goto err;
 	}
 
 	if (close(ttys_fd)) {
 		ret = errno;
-		fprintf(stderr, "%s: close tty failed: %d\n",
-		    __progname, errno);
+		log_warn("%s: close tty failed", __progname);
 		goto err;
 	}
 
@@ -549,8 +576,8 @@ start_vm(struct imsg *imsg)
 		child_taps[i] = opentap();
 		if (child_taps[i] == -1) {
 			ret = errno;
-			fprintf(stderr, "%s: can't open tap for nic %zd (%d)\n",
-			    __progname, i, errno);
+			log_warn("%s: can't open tap for nic %zd",
+			    __progname, i);
 			goto err;
 		}
 	}
@@ -579,31 +606,28 @@ start_vm(struct imsg *imsg)
 	}	
 	else {
 		/* Child */
-		fprintf(stderr, "%s: vm console: %s\n", __progname, ptyn);
-		ret = vmm_create_vm(vcp);
 		setproctitle(vcp->vcp_name);
+		log_procinit(vcp->vcp_name);
+
+		log_info("%s: vm console: %s", __progname, ptyn);
+		ret = vmm_create_vm(vcp);
 		if (ret) {
-			fprintf(stderr, "%s: create vmm ioctl failed - "
-			    "exiting (%d)\n", __progname, ret);
-			_exit(1);
+			errno = ret;
+			fatal("create vmm ioctl failed - exiting");
 		}
 
 		/* Load kernel image */
 		ret = loadelf_main(kernel_fd, vcp->vcp_id, vcp->vcp_memory_size);
 		if (ret) {
-			fprintf(stderr, "%s: failed to load kernel - "
-			    "exiting (%d)\n", __progname, ret);
-			_exit(1);
+			errno = ret;
+			fatal("failed to load kernel - exiting");
 		}
 
 		close(kernel_fd);
 
 		con_fd = ttym_fd;
-		if (fcntl(con_fd, F_SETFL, O_NONBLOCK) == -1) {
-			fprintf(stderr, "%s: failed to set nonblocking mode "
-			    "on console\n", __progname);
-			_exit(1);
-		}
+		if (fcntl(con_fd, F_SETFL, O_NONBLOCK) == -1)		
+			fatal("failed to set nonblocking mode on console");
 
 		/* Execute the vcpu run loop(s) for this VM */
 		ret = run_vm(child_disks, child_taps, vcp);
@@ -721,7 +745,7 @@ start_client_vmd(void)
 
 	pw = getpwnam(VMD_USER);
 	if (pw == NULL) {
-		fprintf(stderr, "%s: no such user %s\n", __progname, VMD_USER);
+		log_warnx("%s: no such user %s", __progname, VMD_USER);
 		return (-1);
 	}
 
@@ -732,16 +756,16 @@ start_client_vmd(void)
 	if (!child_pid) {
 		/* Child */
 		if (chroot(pw->pw_dir) != 0)
-			err(1, "unable to chroot");
+			fatal("unable to chroot");
 		if (chdir("/") != 0)
-			err(1, "unable to chdir");
+			fatal("unable to chdir");
 
 		if (setgroups(1, &pw->pw_gid) == -1)
-			err(1, "setgroups() failed");
+			fatal("setgroups() failed");
 		if (setresgid(pw->pw_gid, pw->pw_gid, pw->pw_gid) == -1)
-			err(1, "setresgid() failed");
+			fatal("setresgid() failed");
 		if (setresuid(pw->pw_uid, pw->pw_uid, pw->pw_uid) == -1)
-			err(1, "setresuid() failed");
+			fatal("setresuid() failed");
 
 		return (0);
 	}
@@ -846,7 +870,7 @@ run_vm(int *child_disks, int *child_taps, struct vm_create_params *vcp)
 	tid = malloc(sizeof(pthread_t) * vcp->vcp_ncpus);
 	vrp = malloc(sizeof(struct vm_run_params *) * vcp->vcp_ncpus);
 	if (tid == NULL || vrp == NULL) {
-		fprintf(stderr, "%s: memory allocation error - exiting.\n",
+		log_warn("%s: memory allocation error - exiting.",
 		    __progname);
 		return (ENOMEM);
 	}
@@ -862,15 +886,15 @@ run_vm(int *child_disks, int *child_taps, struct vm_create_params *vcp)
 	for (i = 0 ; i < vcp->vcp_ncpus; i++) {
 		vrp[i] = malloc(sizeof(struct vm_run_params));
 		if (vrp[i] == NULL) {
-			fprintf(stderr, "%s: memory allocation error - "
-			    "exiting.\n", __progname);
+			log_warn("%s: memory allocation error - "
+			    "exiting.", __progname);
 			/* caller will exit, so skip free'ing */
 			return (ENOMEM);
 		}
 		vrp[i]->vrp_exit = malloc(sizeof(union vm_exit));
 		if (vrp[i]->vrp_exit == NULL) {
-			fprintf(stderr, "%s: memory allocation error - "
-			    "exiting.\n", __progname);
+			log_warn("%s: memory allocation error - "
+			    "exiting.", __progname);
 			/* caller will exit, so skip free'ing */
 			return (ENOMEM);
 		}
@@ -888,14 +912,14 @@ run_vm(int *child_disks, int *child_taps, struct vm_create_params *vcp)
 	/* Wait for all the threads to exit */
 	for (i = 0; i < vcp->vcp_ncpus; i++) {
 		if (pthread_join(tid[i], &exit_status)) {
-			fprintf(stderr, "%s: failed to join thread %zd - "
-			    "exiting\n", __progname, i);
+			log_warn("%s: failed to join thread %zd - "
+			    "exiting", __progname, i);
 			return (EIO);
 		}
 
 		if (exit_status != NULL) {
-			fprintf(stderr, "%s: vm %d vcpu run thread %zd exited "
-			    "abnormally\n", __progname, vcp->vcp_id, i);
+			log_warnx("%s: vm %d vcpu run thread %zd exited "
+			    "abnormally", __progname, vcp->vcp_id, i);
 			ret = EIO;
 		}
 	}
@@ -975,8 +999,8 @@ vcpu_exit_i8253(union vm_exit *vei)
 			    (TIMER_SEL0 | TIMER_SEL1 | TIMER_SEL2);
 			sel = sel >> 6;
 			if (sel > 2) {
-				fprintf(stderr, "%s: i8253 PIT: invalid "
-				    "timer selected (%d)\n",
+				log_warnx("%s: i8253 PIT: invalid "
+				    "timer selected (%d)",
 				    __progname, sel);
 				return;
 			}
@@ -990,8 +1014,8 @@ vcpu_exit_i8253(union vm_exit *vei)
 				 * XXX this seems to be used on occasion, needs
 				 * to be implemented
 				 */
-				fprintf(stderr, "%s: i8253 PIT: 16 bit "
-				    "counter I/O not supported\n",
+				log_warnx("%s: i8253 PIT: 16 bit "
+				    "counter I/O not supported",
 				    __progname);
 				    return;
 			}
@@ -1028,13 +1052,13 @@ vcpu_exit_i8253(union vm_exit *vei)
 				return;
 			}
 
-			fprintf(stderr, "%s: i8253 PIT: unsupported rw mode "
-			    "%d\n", __progname, rw);
+			log_warnx("%s: i8253 PIT: unsupported rw mode "
+			    "%d", __progname, rw);
 			return;
 		} else {
 			/* XXX should this return 0xff? */
-			fprintf(stderr, "%s: i8253 PIT: read from control "
-			    "port unsupported\n", __progname);
+			log_warnx("%s: i8253 PIT: read from control "
+			    "port unsupported", __progname);
 		}
 	} else {
 		sel = vei->vei.vei_port - (TIMER_CNTR0 + TIMER_BASE);
@@ -1108,7 +1132,7 @@ vcpu_process_com_data(union vm_exit *vei)
 		} else {
 			/* XXX should this be com1_regs.data or 0xff? */
 			vei->vei.vei_data = com1_regs.data;
-			fprintf(stderr, "guest reading com1 when not ready\n");
+			log_warnx("guest reading com1 when not ready");
 		}
 
 		/* Reading the data register always clears RXRDY from IIR */
@@ -1242,7 +1266,7 @@ vcpu_process_com_lsr(union vm_exit *vei)
 	 * continue.
 	 */
 	if (vei->vei.vei_dir == 0) {
-		fprintf(stderr, "%s: LSR UART write 0x%x unsupported\n",
+		log_warnx("%s: LSR UART write 0x%x unsupported",
 		    __progname, vei->vei.vei_data);
 	} else {
 		/*
@@ -1274,7 +1298,7 @@ vcpu_process_com_msr(union vm_exit *vei)
 	 * continue.
 	 */
 	if (vei->vei.vei_dir == 0) {
-		fprintf(stderr, "%s: MSR UART write 0x%x unsupported\n",
+		log_warnx("%s: MSR UART write 0x%x unsupported",
 		    __progname, vei->vei.vei_data);
 	} else {
 		/*
@@ -1425,7 +1449,7 @@ vcpu_exit_pci(struct vm_run_params *vrp)
 		intr = pci_handle_io(vrp);
 		break;		
 	default:
-		fprintf(stderr, "%s: unknown PCI register 0x%llx\n",
+		log_warnx("%s: unknown PCI register 0x%llx",
 		    __progname, (uint64_t)vei->vei.vei_port);
 		break;
 	}
@@ -1512,7 +1536,7 @@ vcpu_exit(struct vm_run_params *vrp)
 		 */
 		break;
 	default:
-		fprintf(stderr, "%s: unknown exit reason %d\n",
+		log_warnx("%s: unknown exit reason %d",
 		    __progname, vrp->vrp_exit_reason);
 		return (1);
 	}
@@ -1581,7 +1605,6 @@ vcpu_exit(struct vm_run_params *vrp)
 int
 write_page(uint32_t dst, void *buf, uint32_t len, int do_mask)
 {
-	int ret;
 	struct vm_writepage_params vwp;
 
 	/*
@@ -1596,9 +1619,8 @@ write_page(uint32_t dst, void *buf, uint32_t len, int do_mask)
 	vwp.vwp_vm_id = vm_id;
 	vwp.vwp_len = len;
 	if (ioctl(vmm_fd, VMM_IOC_WRITEPAGE, &vwp) < 0) {
-		ret = errno;
-		fprintf(stderr, "writepage ioctl failed: %d\n", ret);
-		return (ret);
+		log_warn("writepage ioctl failed");
+		return (errno);
 	}
 	return (0);
 }
@@ -1624,7 +1646,6 @@ write_page(uint32_t dst, void *buf, uint32_t len, int do_mask)
 int
 read_page(uint32_t src, void *buf, uint32_t len, int do_mask)
 {
-	int ret;
 	struct vm_readpage_params vrp;
 
 	/*
@@ -1639,9 +1660,8 @@ read_page(uint32_t src, void *buf, uint32_t len, int do_mask)
 	vrp.vrp_vm_id = vm_id;
 	vrp.vrp_len = len;
 	if (ioctl(vmm_fd, VMM_IOC_READPAGE, &vrp) < 0) {
-		ret = errno;
-		fprintf(stderr, "readpage ioctl failed: %d\n", ret);
-		return (ret);
+		log_warn("readpage ioctl failed");
+		return (errno);
 	}
 	return (0);
 }
diff --git a/usr.sbin/vmd/vmd.h b/usr.sbin/vmd/vmd.h
index 768fcb2e612..c960dcfa735 100644
--- a/usr.sbin/vmd/vmd.h
+++ b/usr.sbin/vmd/vmd.h
@@ -1,4 +1,4 @@
-/*	$OpenBSD: vmd.h,v 1.2 2015/11/22 21:51:32 reyk Exp $	*/
+/*	$OpenBSD: vmd.h,v 1.3 2015/11/23 13:04:49 reyk Exp $	*/
 
 /*
  * Copyright (c) 2015 Mike Larkin <mlarkin@openbsd.org>
@@ -16,6 +16,8 @@
  * OR IN CONNECTION WITH THE USE OR PERFORMANCE OF THIS SOFTWARE.
  */
 
+#include <stdarg.h>
+
 #ifndef __VMD_H__
 #define __VMD_H__
 
@@ -27,7 +29,7 @@
 /* #define VMD_DEBUG */
 
 #ifdef VMD_DEBUG
-#define dprintf(x...)   do { fprintf(stderr, x); } while(0)
+#define dprintf(x...)   do { log_debug(x); } while(0)
 #else
 #define dprintf(x...)
 #endif /* VMM_DEBUG */
@@ -51,4 +53,25 @@ enum imsg_type {
 int write_page(uint32_t dst, void *buf, uint32_t, int);
 int read_page(uint32_t dst, void *buf, uint32_t, int);
 
+/* log.c */
+void	log_init(int, int);
+void	log_procinit(const char *);
+void	log_verbose(int);
+void	log_warn(const char *, ...)
+	    __attribute__((__format__ (printf, 1, 2)));
+void	log_warnx(const char *, ...)
+	    __attribute__((__format__ (printf, 1, 2)));
+void	log_info(const char *, ...)
+	    __attribute__((__format__ (printf, 1, 2)));
+void	log_debug(const char *, ...)
+	    __attribute__((__format__ (printf, 1, 2)));
+void	logit(int, const char *, ...)
+	    __attribute__((__format__ (printf, 2, 3)));
+void	vlog(int, const char *, va_list)
+	    __attribute__((__format__ (printf, 2, 0)));
+__dead void fatal(const char *, ...)
+	    __attribute__((__format__ (printf, 1, 2)));
+__dead void fatalx(const char *, ...)
+	    __attribute__((__format__ (printf, 1, 2)));
+
 #endif /* __VMD_H__ */