]> git.saurik.com Git - apple/xnu.git/blobdiff - osfmk/kdp/kdp_udp.c
xnu-3789.70.16.tar.gz
[apple/xnu.git] / osfmk / kdp / kdp_udp.c
index 5cab18769328e1e3a7fcd19a74fafa08a1cc2878..2487c6071fc000ce0a2d98610859a8312ee55b02 100644 (file)
@@ -1,5 +1,5 @@
 /*
- * Copyright (c) 2000-2008 Apple Inc. All rights reserved.
+ * Copyright (c) 2000-2016 Apple Inc. All rights reserved.
  *
  * @APPLE_OSREFERENCE_LICENSE_HEADER_START@
  * 
@@ -35,7 +35,6 @@
  * Kernel Debugging Protocol UDP implementation.
  */
 
-#include <mach_kdb.h>
 #include <mach/boolean.h>
 #include <mach/mach_types.h>
 #include <mach/exception_types.h>
@@ -48,6 +47,7 @@
 #include <kdp/kdp_en_debugger.h>
 #include <kdp/kdp_callout.h>
 #include <kdp/kdp_udp.h>
+#include <kdp/kdp_core.h>
 #if CONFIG_SERIAL_KDP
 #include <kdp/kdp_serial.h>
 #endif
 #include <vm/vm_kern.h> /* kernel_map */
 
 #include <mach/memory_object_types.h>
+#include <machine/pal_routines.h>
 
 #include <sys/msgbuf.h>
 
+/* we just want the link status flags, so undef KERNEL_PRIVATE for this
+ * header file. */
+#undef KERNEL_PRIVATE
+#include <net/if_media.h> 
+#define KERNEL_PRIVATE
+
 #include <string.h>
 
-#define DO_ALIGN       1       /* align all packet data accesses */
+#include <IOKit/IOPlatformExpert.h>
+#include <libkern/version.h>
+
+#include <sys/pgo.h>
+
+extern unsigned int not_in_kdp;
+extern int kdp_snapshot;
+extern void do_stackshot(void);
+
+#ifdef CONFIG_KDP_INTERACTIVE_DEBUGGING
+
+extern int      inet_aton(const char *, struct kdp_in_addr *); /* in libkern */
+extern char    *inet_ntoa_r(struct kdp_in_addr ina, char *buf,
+    size_t buflen); /* in libkern */
+
+#define DO_ALIGN       1             /* align all packet data accesses */
+#define KDP_SERIAL_IPADDR  0xABADBABE /* IP address used for serial KDP */
+#define LINK_UP_STATUS     (IFM_AVALID | IFM_ACTIVE)
 
 extern int kdp_getc(void);
 extern int reattach_wait;
 
-extern int serial_getc(void);
-extern void serial_putc(char);
-extern int serial_init(void);
-
 static u_short ip_id;                          /* ip packet ctr, for ids */
 
 /*     @(#)udp_usrreq.c        2.2 88/05/23 4.0NFSSRC SMI;     from UCB 7.1 6/5/86     */
@@ -80,47 +100,171 @@ static u_short ip_id;                          /* ip packet ctr, for ids */
  * Per RFC 768, August, 1980.
  */
 #define UDP_TTL        60 /* deflt time to live for UDP packets */
-int    udp_ttl = UDP_TTL;
+static int udp_ttl = UDP_TTL;
 static unsigned char   exception_seq;
 
+struct kdp_ipovly {
+        uint32_t ih_next, ih_prev;     /* for protocol sequence q's */
+        u_char  ih_x1;                 /* (unused) */
+        u_char  ih_pr;                 /* protocol */
+        short   ih_len;                        /* protocol length */
+        struct  kdp_in_addr ih_src;    /* source internet address */
+        struct  kdp_in_addr ih_dst;    /* destination internet address */
+};
+
+struct kdp_udphdr {
+       u_short uh_sport;               /* source port */
+       u_short uh_dport;               /* destination port */
+       short   uh_ulen;                /* udp length */
+       u_short uh_sum;                 /* udp checksum */
+};
+
+struct  kdp_udpiphdr {
+        struct  kdp_ipovly ui_i;       /* overlaid ip structure */
+        struct  kdp_udphdr ui_u;       /* udp header */
+};
+#define        ui_next         ui_i.ih_next
+#define        ui_prev         ui_i.ih_prev
+#define        ui_x1           ui_i.ih_x1
+#define        ui_pr           ui_i.ih_pr
+#define        ui_len          ui_i.ih_len
+#define        ui_src          ui_i.ih_src
+#define        ui_dst          ui_i.ih_dst
+#define        ui_sport        ui_u.uh_sport
+#define        ui_dport        ui_u.uh_dport
+#define        ui_ulen         ui_u.uh_ulen
+#define        ui_sum          ui_u.uh_sum
+
+struct kdp_ip {
+       union {
+               uint32_t ip_w;
+               struct {
+                       unsigned int
+#ifdef __LITTLE_ENDIAN__
+                       ip_xhl:4,       /* header length */
+                       ip_xv:4,        /* version */
+                       ip_xtos:8,      /* type of service */
+                       ip_xlen:16;     /* total length */
+#endif
+#ifdef __BIG_ENDIAN__
+                       ip_xv:4,        /* version */
+                       ip_xhl:4,       /* header length */
+                       ip_xtos:8,      /* type of service */
+                       ip_xlen:16;     /* total length */
+#endif
+               } ip_x;
+       } ip_vhltl;
+        u_short ip_id;                 /* identification */
+        short   ip_off;                        /* fragment offset field */
+#define        IP_DF 0x4000                    /* dont fragment flag */
+#define        IP_MF 0x2000                    /* more fragments flag */
+#define        IP_OFFMASK 0x1fff               /* mask for fragmenting bits */
+        u_char  ip_ttl;                        /* time to live */
+        u_char  ip_p;                  /* protocol */
+        u_short ip_sum;                        /* checksum */
+        struct  kdp_in_addr ip_src,ip_dst;  /* source and dest address */
+};
+#define        ip_v            ip_vhltl.ip_x.ip_xv
+#define        ip_hl           ip_vhltl.ip_x.ip_xhl
+#define        ip_tos          ip_vhltl.ip_x.ip_xtos
+#define        ip_len          ip_vhltl.ip_x.ip_xlen
+
+#define        IPPROTO_UDP     17
+#define        IPVERSION       4
+
+#define        ETHERTYPE_IP    0x0800  /* IP protocol */
+
+/*
+ * Ethernet Address Resolution Protocol.
+ *
+ * See RFC 826 for protocol description.  Structure below is adapted
+ * to resolving internet addresses.  Field names used correspond to
+ * RFC 826.
+ */
+
+#define        ETHERTYPE_ARP   0x0806  /* Addr. resolution protocol */
+
+struct  kdp_arphdr {
+       u_short ar_hrd;         /* format of hardware address */
+#define        ARPHRD_ETHER    1       /* ethernet hardware format */
+#define        ARPHRD_FRELAY   15      /* frame relay hardware format */
+       u_short ar_pro;         /* format of protocol address */
+       u_char  ar_hln;         /* length of hardware address */
+       u_char  ar_pln;         /* length of protocol address */
+       u_short ar_op;          /* one of: */
+#define        ARPOP_REQUEST   1       /* request to resolve address */
+#define        ARPOP_REPLY     2       /* response to previous request */
+#define        ARPOP_REVREQUEST 3      /* request protocol address given hardware */
+#define        ARPOP_REVREPLY  4       /* response giving protocol address */
+#define        ARPOP_INVREQUEST 8      /* request to identify peer */
+#define        ARPOP_INVREPLY  9       /* response identifying peer */
+};
+
+struct  kdp_ether_arp {
+       struct  kdp_arphdr ea_hdr;              /* fixed-size header */
+       u_char  arp_sha[ETHER_ADDR_LEN];        /* sender hardware address */
+       u_char  arp_spa[4];                     /* sender protocol address */
+       u_char  arp_tha[ETHER_ADDR_LEN];        /* target hardware address */
+       u_char  arp_tpa[4];                     /* target protocol address */
+};
+#define        arp_hrd ea_hdr.ar_hrd
+#define        arp_pro ea_hdr.ar_pro
+#define        arp_hln ea_hdr.ar_hln
+#define        arp_pln ea_hdr.ar_pln
+#define        arp_op  ea_hdr.ar_op
+
+#define        ETHERMTU        1500
+#define        ETHERHDRSIZE    14
+#define        ETHERCRC        4
+#define        KDP_MAXPACKET   (ETHERHDRSIZE + ETHERMTU + ETHERCRC)
+
 static struct {
-    unsigned char      data[KDP_MAXPACKET];
-    unsigned int       off, len;
-    boolean_t          input;
+       unsigned char   data[KDP_MAXPACKET];
+       unsigned int    off, len;
+       boolean_t               input;
 } pkt, saved_reply;
 
 struct kdp_manual_pkt manual_pkt;
 
 struct {
-    struct {
-       struct in_addr          in;
-       struct ether_addr       ea;
-    } loc;
-    struct {
-       struct in_addr          in;
-       struct ether_addr       ea;
-    } rmt;
+       struct {
+               struct kdp_in_addr      in;
+               struct kdp_ether_addr   ea;
+       } loc;
+       struct {
+               struct kdp_in_addr      in;
+               struct kdp_ether_addr   ea;
+       } rmt;
 } adr;
 
 static const char
 *exception_message[] = {
-    "Unknown",
-    "Memory access",           /* EXC_BAD_ACCESS */
-    "Failed instruction",      /* EXC_BAD_INSTRUCTION */
-    "Arithmetic",              /* EXC_ARITHMETIC */
-    "Emulation",               /* EXC_EMULATION */
-    "Software",                        /* EXC_SOFTWARE */
-    "Breakpoint"               /* EXC_BREAKPOINT */
+       "Unknown",
+       "Memory access",        /* EXC_BAD_ACCESS */
+       "Failed instruction",   /* EXC_BAD_INSTRUCTION */
+       "Arithmetic",           /* EXC_ARITHMETIC */
+       "Emulation",            /* EXC_EMULATION */
+       "Software",             /* EXC_SOFTWARE */
+       "Breakpoint"            /* EXC_BREAKPOINT */
 };
 
 volatile int kdp_flag = 0;
+boolean_t kdp_corezip_disabled = 0;
 
-static kdp_send_t kdp_en_send_pkt;
+kdp_send_t    kdp_en_send_pkt;
 static kdp_receive_t kdp_en_recv_pkt;
+static kdp_link_t    kdp_en_linkstatus;
+static kdp_mode_t    kdp_en_setmode;
 
+#if CONFIG_SERIAL_KDP
+static void kdp_serial_send(void *rpkt, unsigned int rpkt_len);
+#define KDP_SERIAL_ENABLED()  (kdp_en_send_pkt == kdp_serial_send)
+#else
+#define KDP_SERIAL_ENABLED()  (0)
+#endif
 
 static uint32_t kdp_current_ip_address = 0;
-static struct ether_addr kdp_current_mac_address = {{0, 0, 0, 0, 0, 0}};
+static struct kdp_ether_addr kdp_current_mac_address = {{0, 0, 0, 0, 0, 0}};
 static void *kdp_current_ifp;
 
 static void kdp_handler( void *);
@@ -130,17 +274,19 @@ static uint32_t parsed_router_ip = 0;
 static uint32_t router_ip = 0;
 static uint32_t target_ip = 0;
 
+static boolean_t save_ip_in_nvram = FALSE;
+
 static volatile boolean_t panicd_specified = FALSE;
 static boolean_t router_specified = FALSE;
 static boolean_t corename_specified = FALSE;
 static unsigned int panicd_port = CORE_REMOTE_PORT;
 
-static struct ether_addr etherbroadcastaddr = {{0xff, 0xff, 0xff, 0xff, 0xff, 0xff}};
+static struct kdp_ether_addr etherbroadcastaddr = {{0xff, 0xff, 0xff, 0xff, 0xff, 0xff}};
 
-static struct ether_addr router_mac = {{0, 0, 0 , 0, 0, 0}};
-static struct ether_addr destination_mac = {{0, 0, 0 , 0, 0, 0}};
-static struct ether_addr temp_mac = {{0, 0, 0 , 0, 0, 0}};
-static struct ether_addr current_resolved_MAC = {{0, 0, 0 , 0, 0, 0}};
+static struct kdp_ether_addr router_mac = {{0, 0, 0 , 0, 0, 0}};
+static struct kdp_ether_addr destination_mac = {{0, 0, 0 , 0, 0, 0}};
+static struct kdp_ether_addr temp_mac = {{0, 0, 0 , 0, 0, 0}};
+static struct kdp_ether_addr current_resolved_MAC = {{0, 0, 0 , 0, 0, 0}};
 
 static boolean_t flag_panic_dump_in_progress = FALSE;
 static boolean_t flag_router_mac_initialized = FALSE;
@@ -151,71 +297,56 @@ static boolean_t flag_arp_resolved = FALSE;
 static unsigned int panic_timeout = 100000;
 static unsigned int last_panic_port = CORE_REMOTE_PORT;
 
-unsigned int SEGSIZE = 512;
+#define KDP_THROTTLE_VALUE       (10ULL * NSEC_PER_SEC)
 
+uint32_t kdp_crashdump_pkt_size = 512;
+#define KDP_LARGE_CRASHDUMP_PKT_SIZE (1440 - 6 - sizeof(struct kdp_udpiphdr))
 static char panicd_ip_str[20];
 static char router_ip_str[20];
-static char corename_str[50];
+static char corename_str[100];
 
 static unsigned int panic_block = 0;
 volatile unsigned int kdp_trigger_core_dump = 0;
 __private_extern__ volatile unsigned int flag_kdp_trigger_reboot = 0;
 
-extern unsigned int not_in_kdp;
 
 extern unsigned int disableConsoleOutput;
 
 extern void            kdp_call(void);
 extern boolean_t       kdp_call_kdb(void);
-extern int             kern_dump(void);
 
 void * kdp_get_interface(void);
-void   kdp_set_gateway_mac(void *);
-void   kdp_set_ip_and_mac_addresses(struct in_addr *, struct ether_addr *);
-void   kdp_set_interface(void *);
+void    kdp_set_gateway_mac(void *gatewaymac);
+void   kdp_set_ip_and_mac_addresses(struct kdp_in_addr *ipaddr, struct kdp_ether_addr *);
+void   kdp_set_interface(void *interface, const struct kdp_ether_addr *macaddr);
 
 void                   kdp_disable_arp(void);
-static void            kdp_arp_reply(struct ether_arp *);
-static void            kdp_process_arp_reply(struct ether_arp *);
-static boolean_t       kdp_arp_resolve(uint32_t, struct ether_addr *);
+static void            kdp_arp_reply(struct kdp_ether_arp *);
+static void            kdp_process_arp_reply(struct kdp_ether_arp *);
+static boolean_t       kdp_arp_resolve(uint32_t, struct kdp_ether_addr *);
 
 static volatile unsigned       kdp_reentry_deadline;
-#if    defined(__LP64__)
-uint32_t kdp_crashdump_feature_mask = KDP_FEATURE_LARGE_CRASHDUMPS;
-static uint32_t        kdp_feature_large_crashdumps;
-#endif
-
-static boolean_t       gKDPDebug = FALSE;
-#define KDP_DEBUG(...) if (gKDPDebug) printf(__VA_ARGS__);
-
-int kdp_snapshot = 0;
-static int stack_snapshot_ret = 0;
-static unsigned stack_snapshot_bytes_traced = 0;
-
-static void *stack_snapshot_buf;
-static uint32_t stack_snapshot_bufsize;
-static int stack_snapshot_pid;
-static uint32_t stack_snapshot_options;
 
-static unsigned int old_debugger;
+static uint32_t kdp_crashdump_feature_mask = KDP_FEATURE_LARGE_CRASHDUMPS | KDP_FEATURE_LARGE_PKT_SIZE;
+uint32_t kdp_feature_large_crashdumps, kdp_feature_large_pkt_size;
 
-void
-kdp_snapshot_preflight(int pid, void * tracebuf, uint32_t tracebuf_size,
-    uint32_t options);
-
-void
-kdp_snapshot_postflight(void);
+char kdp_kernelversion_string[256];
 
-extern int
-kdp_stackshot(int pid, void *tracebuf, uint32_t tracebuf_size,
-    unsigned trace_options, uint32_t *pbytesTraced);
+static boolean_t       gKDPDebug = FALSE;
 
-int
-kdp_stack_snapshot_geterror(void);
+#if WITH_CONSISTENT_DBG
+#include <arm/caches_internal.h>
+extern volatile struct xnu_hw_shmem_dbg_command_info *hwsd_info;
+#endif
 
-int
-kdp_stack_snapshot_bytes_traced(void);
+#define KDP_DEBUG(...) if (gKDPDebug) printf(__VA_ARGS__);
 
+#define SBLOCKSZ (2048)
+uint64_t kdp_dump_start_time = 0;
+uint64_t kdp_min_superblock_dump_time = ~1ULL;
+uint64_t kdp_max_superblock_dump_time = 0;
+uint64_t kdp_superblock_dump_time = 0;
+uint64_t kdp_superblock_dump_start_time = 0;
 static thread_call_t
 kdp_timer_call;
 
@@ -230,6 +361,56 @@ kdp_timer_callout_init(void) {
 }
 
 
+/* only send/receive data if the link is up */
+inline static void
+wait_for_link(void)
+{
+       static int first = 0;
+
+       if (!kdp_en_linkstatus)
+               return;
+
+       while (((*kdp_en_linkstatus)() & LINK_UP_STATUS) != LINK_UP_STATUS) {
+               if (first)
+                       continue;
+
+               first = 1;
+               printf("Waiting for link to become available.\n");
+               kprintf("Waiting for link to become available.\n");
+       }
+}
+
+
+inline static void
+kdp_send_data(void *packet, unsigned int len)
+{
+       wait_for_link();
+       (*kdp_en_send_pkt)(packet, len);
+}
+
+
+inline static void
+kdp_receive_data(void *packet, unsigned int *len, unsigned int timeout)
+{
+       wait_for_link();
+       (*kdp_en_recv_pkt)(packet, len, timeout);
+}
+
+
+void
+kdp_register_link(kdp_link_t link, kdp_mode_t mode)
+{
+       kdp_en_linkstatus = link;
+       kdp_en_setmode    = mode;
+}
+
+void
+kdp_unregister_link(__unused kdp_link_t link, __unused kdp_mode_t mode)
+{
+       kdp_en_linkstatus = NULL;
+       kdp_en_setmode    = NULL;
+}
+
 void
 kdp_register_send_receive(
        kdp_send_t      send, 
@@ -237,20 +418,14 @@ kdp_register_send_receive(
 {
        unsigned int    debug = 0;
 
-       debug_log_init();
-
-       kdp_timer_callout_init();
-
        PE_parse_boot_argn("debug", &debug, sizeof (debug));
-#if    defined(__LP64__)
-       kdp_crashdump_feature_mask = htonl(kdp_crashdump_feature_mask);
-#endif
+
 
        if (!debug)
                return;
 
-       kdp_en_send_pkt = send;
-       kdp_en_recv_pkt = receive;
+       kdp_en_send_pkt   = send;
+       kdp_en_recv_pkt   = receive;
 
        if (debug & DB_KDP_BP_DIS)
                kdp_flag |= KDP_BP_DIS;   
@@ -270,6 +445,8 @@ kdp_register_send_receive(
        if (debug & DB_PANICLOG_DUMP)
                kdp_flag |= PANIC_LOG_DUMP;
 
+       kdp_corezip_disabled = (0 != (debug & DB_DISABLE_GZIP_CORE));
+
        if (PE_parse_boot_argn("_panicd_ip", panicd_ip_str, sizeof (panicd_ip_str)))
                panicd_specified = TRUE;
 
@@ -286,8 +463,8 @@ kdp_register_send_receive(
                corename_specified = TRUE;
 
        kdp_flag |= KDP_READY;
-       if (current_debugger == NO_CUR_DB)
-               current_debugger = KDP_CUR_DB;
+
+       current_debugger = KDP_CUR_DB;
        if ((kdp_current_ip_address != 0) && halt_in_debugger) {
                kdp_call(); 
                halt_in_debugger=0;
@@ -302,47 +479,8 @@ kdp_unregister_send_receive(
        if (current_debugger == KDP_CUR_DB)
                current_debugger = NO_CUR_DB;
        kdp_flag &= ~KDP_READY;
-       kdp_en_send_pkt = NULL;
-       kdp_en_recv_pkt = NULL;
-}
-
-/* Cache stack snapshot parameters in preparation for a trace */
-void
-kdp_snapshot_preflight(int pid, void * tracebuf, uint32_t tracebuf_size, uint32_t options)
-{
-       stack_snapshot_pid = pid;
-       stack_snapshot_buf = tracebuf;
-       stack_snapshot_bufsize = tracebuf_size;
-       stack_snapshot_options = options;
-       kdp_snapshot++;
-       /* Mark this debugger as active, since the polled mode driver that 
-        * ordinarily does this may not be enabled (yet), or since KDB may be
-        * the primary debugger.
-        */
-       old_debugger = current_debugger;
-       if (old_debugger != KDP_CUR_DB) {
-               current_debugger = KDP_CUR_DB;
-       }
-}
-
-void
-kdp_snapshot_postflight(void)
-{
-       kdp_snapshot--;
-       if ((kdp_en_send_pkt == NULL) || (old_debugger == KDB_CUR_DB))
-               current_debugger = old_debugger;
-}
-
-int
-kdp_stack_snapshot_geterror(void)
-{
-       return stack_snapshot_ret;
-}
-
-int
-kdp_stack_snapshot_bytes_traced(void)
-{
-       return stack_snapshot_bytes_traced;
+       kdp_en_send_pkt   = NULL;
+       kdp_en_recv_pkt   = NULL;
 }
 
 static void
@@ -359,7 +497,7 @@ enaddr_copy(
        void    *dst
 )
 {
-       bcopy((char *)src, (char *)dst, sizeof (struct ether_addr));
+       bcopy((char *)src, (char *)dst, sizeof (struct kdp_ether_addr));
 }
 
 static unsigned short
@@ -390,26 +528,26 @@ kdp_reply(
           const boolean_t         sideband
           )
 {
-       struct udpiphdr         aligned_ui, *ui = &aligned_ui;
-       struct ip               aligned_ip, *ip = &aligned_ip;
-       struct in_addr          tmp_ipaddr;
-       struct ether_addr       tmp_enaddr;
-       struct ether_header     *eh = NULL;
+       struct kdp_udpiphdr     aligned_ui, *ui = &aligned_ui;
+       struct kdp_ip           aligned_ip, *ip = &aligned_ip;
+       struct kdp_in_addr      tmp_ipaddr;
+       struct kdp_ether_addr   tmp_enaddr;
+       struct kdp_ether_header *eh = NULL;
     
        if (!pkt.input)
                kdp_panic("kdp_reply");
        
-       pkt.off -= (unsigned int)sizeof (struct udpiphdr);
+       pkt.off -= (unsigned int)sizeof (struct kdp_udpiphdr);
 
 #if DO_ALIGN    
        bcopy((char *)&pkt.data[pkt.off], (char *)ui, sizeof(*ui));
 #else
-       ui = (struct udpiphdr *)&pkt.data[pkt.off];
+       ui = (struct kdp_udpiphdr *)&pkt.data[pkt.off];
 #endif
        ui->ui_next = ui->ui_prev = 0;
        ui->ui_x1 = 0;
        ui->ui_pr = IPPROTO_UDP;
-       ui->ui_len = htons((u_short)pkt.len + sizeof (struct udphdr));
+       ui->ui_len = htons((u_short)pkt.len + sizeof (struct kdp_udphdr));
        tmp_ipaddr = ui->ui_src;
        ui->ui_src = ui->ui_dst;
        ui->ui_dst = tmp_ipaddr;
@@ -421,12 +559,12 @@ kdp_reply(
        bcopy((char *)ui, (char *)&pkt.data[pkt.off], sizeof(*ui));
        bcopy((char *)&pkt.data[pkt.off], (char *)ip, sizeof(*ip));
 #else
-       ip = (struct ip *)&pkt.data[pkt.off];
+       ip = (struct kdp_ip *)&pkt.data[pkt.off];
 #endif
-       ip->ip_len = htons(sizeof (struct udpiphdr) + pkt.len);
+       ip->ip_len = htons(sizeof (struct kdp_udpiphdr) + pkt.len);
        ip->ip_v = IPVERSION;
        ip->ip_id = htons(ip_id++);
-       ip->ip_hl = sizeof (struct ip) >> 2;
+       ip->ip_hl = sizeof (struct kdp_ip) >> 2;
        ip->ip_ttl = udp_ttl;
        ip->ip_sum = 0;
        ip->ip_sum = htons(~ip_sum((unsigned char *)ip, ip->ip_hl));
@@ -434,23 +572,24 @@ kdp_reply(
        bcopy((char *)ip, (char *)&pkt.data[pkt.off], sizeof(*ip));
 #endif
     
-       pkt.len += (unsigned int)sizeof (struct udpiphdr);
+       pkt.len += (unsigned int)sizeof (struct kdp_udpiphdr);
     
-       pkt.off -= (unsigned int)sizeof (struct ether_header);
+       pkt.off -= (unsigned int)sizeof (struct kdp_ether_header);
     
-       eh = (struct ether_header *)&pkt.data[pkt.off];
+       eh = (struct kdp_ether_header *)&pkt.data[pkt.off];
        enaddr_copy(eh->ether_shost, &tmp_enaddr);
        enaddr_copy(eh->ether_dhost, eh->ether_shost);
        enaddr_copy(&tmp_enaddr, eh->ether_dhost);
        eh->ether_type = htons(ETHERTYPE_IP);
     
-       pkt.len += (unsigned int)sizeof (struct ether_header);
+       pkt.len += (unsigned int)sizeof (struct kdp_ether_header);
     
        // save reply for possible retransmission
+       assert(pkt.len <= KDP_MAXPACKET);
        if (!sideband)
-               bcopy((char *)&pkt, (char *)&saved_reply, sizeof(pkt));
+               bcopy((char *)&pkt, (char *)&saved_reply, sizeof(saved_reply));
 
-       (*kdp_en_send_pkt)(&pkt.data[pkt.off], pkt.len);
+       kdp_send_data(&pkt.data[pkt.off], pkt.len);
 
        // increment expected sequence number
        if (!sideband) 
@@ -462,66 +601,118 @@ kdp_send(
     unsigned short             remote_port
 )
 {
-    struct udpiphdr            aligned_ui, *ui = &aligned_ui;
-    struct ip                  aligned_ip, *ip = &aligned_ip;
-    struct ether_header                *eh;
-    
-    if (pkt.input)
-       kdp_panic("kdp_send");
+       struct kdp_udpiphdr             aligned_ui, *ui = &aligned_ui;
+       struct kdp_ip           aligned_ip, *ip = &aligned_ip;
+       struct kdp_ether_header *eh;
+
+       if (pkt.input)
+               kdp_panic("kdp_send");
 
-    pkt.off -= (unsigned int)sizeof (struct udpiphdr);
+       pkt.off -= (unsigned int)sizeof (struct kdp_udpiphdr);
 
 #if DO_ALIGN
-    bcopy((char *)&pkt.data[pkt.off], (char *)ui, sizeof(*ui));
+       bcopy((char *)&pkt.data[pkt.off], (char *)ui, sizeof(*ui));
 #else
-    ui = (struct udpiphdr *)&pkt.data[pkt.off];
+       ui = (struct kdp_udpiphdr *)&pkt.data[pkt.off];
 #endif
-    ui->ui_next = ui->ui_prev = 0;
-    ui->ui_x1 = 0;
-    ui->ui_pr = IPPROTO_UDP;
-    ui->ui_len = htons((u_short)pkt.len + sizeof (struct udphdr));
-    ui->ui_src = adr.loc.in;
-    ui->ui_dst = adr.rmt.in;
-    ui->ui_sport = htons(KDP_REMOTE_PORT);
-    ui->ui_dport = remote_port;
-    ui->ui_ulen = ui->ui_len;
-    ui->ui_sum = 0;
+       ui->ui_next = ui->ui_prev = 0;
+       ui->ui_x1 = 0;
+       ui->ui_pr = IPPROTO_UDP;
+       ui->ui_len = htons((u_short)pkt.len + sizeof (struct kdp_udphdr));
+       ui->ui_src = adr.loc.in;
+       ui->ui_dst = adr.rmt.in;
+       ui->ui_sport = htons(KDP_REMOTE_PORT);
+       ui->ui_dport = remote_port;
+       ui->ui_ulen = ui->ui_len;
+       ui->ui_sum = 0;
 #if DO_ALIGN
-    bcopy((char *)ui, (char *)&pkt.data[pkt.off], sizeof(*ui));
-    bcopy((char *)&pkt.data[pkt.off], (char *)ip, sizeof(*ip));
+       bcopy((char *)ui, (char *)&pkt.data[pkt.off], sizeof(*ui));
+       bcopy((char *)&pkt.data[pkt.off], (char *)ip, sizeof(*ip));
 #else
-    ip = (struct ip *)&pkt.data[pkt.off];
+       ip = (struct kdp_ip *)&pkt.data[pkt.off];
 #endif
-    ip->ip_len = htons(sizeof (struct udpiphdr) + pkt.len);
-    ip->ip_v = IPVERSION;
-    ip->ip_id = htons(ip_id++);
-    ip->ip_hl = sizeof (struct ip) >> 2;
-    ip->ip_ttl = udp_ttl;
-    ip->ip_sum = 0;
-    ip->ip_sum = htons(~ip_sum((unsigned char *)ip, ip->ip_hl));
+       ip->ip_len = htons(sizeof (struct kdp_udpiphdr) + pkt.len);
+       ip->ip_v = IPVERSION;
+       ip->ip_id = htons(ip_id++);
+       ip->ip_hl = sizeof (struct kdp_ip) >> 2;
+       ip->ip_ttl = udp_ttl;
+       ip->ip_sum = 0;
+       ip->ip_sum = htons(~ip_sum((unsigned char *)ip, ip->ip_hl));
 #if DO_ALIGN
-    bcopy((char *)ip, (char *)&pkt.data[pkt.off], sizeof(*ip));
+       bcopy((char *)ip, (char *)&pkt.data[pkt.off], sizeof(*ip));
 #endif
-    
-    pkt.len += (unsigned int)sizeof (struct udpiphdr);
-    
-    pkt.off -= (unsigned int)sizeof (struct ether_header);
-    
-    eh = (struct ether_header *)&pkt.data[pkt.off];
-    enaddr_copy(&adr.loc.ea, eh->ether_shost);
-    enaddr_copy(&adr.rmt.ea, eh->ether_dhost);
-    eh->ether_type = htons(ETHERTYPE_IP);
-    
-    pkt.len += (unsigned int)sizeof (struct ether_header);
-    (*kdp_en_send_pkt)(&pkt.data[pkt.off], pkt.len);
+
+       pkt.len += (unsigned int)sizeof (struct kdp_udpiphdr);
+
+       pkt.off -= (unsigned int)sizeof (struct kdp_ether_header);
+
+       eh = (struct kdp_ether_header *)&pkt.data[pkt.off];
+       enaddr_copy(&adr.loc.ea, eh->ether_shost);
+       enaddr_copy(&adr.rmt.ea, eh->ether_dhost);
+       eh->ether_type = htons(ETHERTYPE_IP);
+
+       pkt.len += (unsigned int)sizeof (struct kdp_ether_header);
+       kdp_send_data(&pkt.data[pkt.off], pkt.len);
 }
 
-/* We don't interpret this pointer, we just give it to the
-bsd stack so it can decide when to set the MAC and IP info. */
+
+inline static void
+debugger_if_necessary(void)
+{
+       if ((current_debugger == KDP_CUR_DB) && halt_in_debugger) {
+               kdp_call();
+               halt_in_debugger=0;
+       }
+}
+
+
+/* We don't interpret this pointer, we just give it to the bsd stack
+   so it can decide when to set the MAC and IP info. We'll
+   early initialize the MAC/IP info if we can so that we can use
+   KDP early in boot. These values may subsequently get over-written
+   when the interface gets initialized for real.
+*/
 void
-kdp_set_interface(void *ifp)
+kdp_set_interface(void *ifp, const struct kdp_ether_addr *macaddr)
 {
+       char kdpstr[80];
+        struct kdp_in_addr addr = { 0 };
+        unsigned int len;
+        
        kdp_current_ifp = ifp;
+
+        if (PE_parse_boot_argn("kdp_ip_addr", kdpstr, sizeof(kdpstr))) {
+            /* look for a static ip address */
+            if (inet_aton(kdpstr, &addr) == FALSE)
+                goto done;
+
+            goto config_network;
+        }
+
+        /* use saved ip address */
+        save_ip_in_nvram = TRUE;
+
+        len = sizeof(kdpstr);
+        if (PEReadNVRAMProperty("_kdp_ipstr", kdpstr, &len) == FALSE)
+            goto done;
+
+        kdpstr[len < sizeof(kdpstr) ? len : sizeof(kdpstr) - 1] = '\0';
+        if (inet_aton(kdpstr, &addr) == FALSE)
+            goto done;
+
+config_network:
+        kdp_current_ip_address = addr.s_addr;
+        if (macaddr)
+            kdp_current_mac_address = *macaddr;
+
+        /* we can't drop into the debugger at this point because the
+           link will likely not be up. when getDebuggerLinkStatus() support gets
+           added to the appropriate network drivers, adding the
+           following will enable this capability:
+           debugger_if_necessary();
+        */
+done:
+        return;
 }
 
 void *
@@ -532,34 +723,63 @@ kdp_get_interface(void)
 
 void 
 kdp_set_ip_and_mac_addresses(
-       struct in_addr          *ipaddr, 
-       struct ether_addr       *macaddr)
+       struct kdp_in_addr              *ipaddr, 
+       struct kdp_ether_addr   *macaddr)
 {
-       kdp_current_ip_address = ipaddr->s_addr;
-       kdp_current_mac_address = *macaddr;
-       if ((current_debugger == KDP_CUR_DB) && halt_in_debugger) {
-               kdp_call();
-               halt_in_debugger=0;
+       static uint64_t last_time    = (uint64_t) -1;
+       static uint64_t throttle_val = 0;
+       uint64_t cur_time;
+       char addr[16];
+
+       if (kdp_current_ip_address == ipaddr->s_addr)
+               goto done;
+
+       /* don't replace if serial debugging is configured */
+       if (!KDP_SERIAL_ENABLED() ||
+           (kdp_current_ip_address != KDP_SERIAL_IPADDR)) {
+               kdp_current_mac_address = *macaddr;
+               kdp_current_ip_address  = ipaddr->s_addr;
+       }
+
+       if (save_ip_in_nvram == FALSE)
+               goto done;
+
+       if (inet_ntoa_r(*ipaddr, addr, sizeof(addr)) == NULL)
+               goto done;
+
+       /* throttle writes if needed */
+       if (!throttle_val)
+               nanoseconds_to_absolutetime(KDP_THROTTLE_VALUE, &throttle_val);
+
+       cur_time = mach_absolute_time();
+       if (last_time == (uint64_t) -1 ||
+           ((cur_time - last_time) > throttle_val)) {
+               PEWriteNVRAMProperty("_kdp_ipstr", addr,
+                               (const unsigned int) strlen(addr));
        }
+       last_time = cur_time;
+
+done:
+       debugger_if_necessary();
 }
 
 void
 kdp_set_gateway_mac(void *gatewaymac)
 {
-  router_mac = *(struct ether_addr *)gatewaymac;
-  flag_router_mac_initialized = TRUE;
+       router_mac = *(struct kdp_ether_addr *)gatewaymac;
+       flag_router_mac_initialized = TRUE;
 } 
 
-struct ether_addr 
+struct kdp_ether_addr 
 kdp_get_mac_addr(void)
 {
-  return kdp_current_mac_address;
+       return kdp_current_mac_address;
 }
 
 unsigned int 
 kdp_get_ip_address(void)
 {
-  return (unsigned int)kdp_current_ip_address;
+       return (unsigned int)kdp_current_ip_address;
 }
 
 void
@@ -571,10 +791,10 @@ kdp_disable_arp(void)
 static void
 kdp_arp_dispatch(void)
 {
-       struct ether_arp        aligned_ea, *ea = &aligned_ea;
+       struct kdp_ether_arp    aligned_ea, *ea = &aligned_ea;
        unsigned                arp_header_offset;
 
-       arp_header_offset = (unsigned)sizeof(struct ether_header) + pkt.off;
+       arp_header_offset = (unsigned)sizeof(struct kdp_ether_header) + pkt.off;
        memcpy((void *)ea, (void *)&pkt.data[arp_header_offset], sizeof(*ea));
 
        switch(ntohs(ea->arp_op)) {
@@ -590,18 +810,18 @@ kdp_arp_dispatch(void)
 }
 
 static void
-kdp_process_arp_reply(struct ether_arp *ea)
+kdp_process_arp_reply(struct kdp_ether_arp *ea)
 {
        /* Are we interested in ARP replies? */
        if (flag_arp_resolved == TRUE)
                return;
 
        /* Did we receive a reply from the right source? */
-       if (((struct in_addr *)(ea->arp_spa))->s_addr != target_ip)
+       if (((struct kdp_in_addr *)(ea->arp_spa))->s_addr != target_ip)
          return;
 
        flag_arp_resolved = TRUE;
-       current_resolved_MAC = *(struct ether_addr *) (ea->arp_sha);
+       current_resolved_MAC = *(struct kdp_ether_addr *) (ea->arp_sha);
 
        return;
 }
@@ -611,15 +831,15 @@ kdp_process_arp_reply(struct ether_arp *ea)
  */
 
 static void 
-kdp_arp_reply(struct ether_arp *ea)
+kdp_arp_reply(struct kdp_ether_arp *ea)
 {
-       struct ether_header     *eh;
+       struct kdp_ether_header *eh;
 
-       struct in_addr          isaddr, itaddr, myaddr;
-       struct ether_addr       my_enaddr;
+       struct kdp_in_addr              isaddr, itaddr, myaddr;
+       struct kdp_ether_addr   my_enaddr;
 
-       eh = (struct ether_header *)&pkt.data[pkt.off];
-       pkt.off += (unsigned int)sizeof(struct ether_header);
+       eh = (struct kdp_ether_header *)&pkt.data[pkt.off];
+       pkt.off += (unsigned int)sizeof(struct kdp_ether_header);
 
        if(ntohs(ea->arp_op) != ARPOP_REQUEST)
          return;
@@ -653,18 +873,18 @@ kdp_arp_reply(struct ether_arp *ea)
                (void)memcpy(eh->ether_shost, &my_enaddr, sizeof(eh->ether_shost));
                eh->ether_type = htons(ETHERTYPE_ARP);
                (void)memcpy(&pkt.data[pkt.off], ea, sizeof(*ea));
-               pkt.off -= (unsigned int)sizeof (struct ether_header);
+               pkt.off -= (unsigned int)sizeof (struct kdp_ether_header);
                /* pkt.len is still the length we want, ether_header+ether_arp */
-               (*kdp_en_send_pkt)(&pkt.data[pkt.off], pkt.len);
+               kdp_send_data(&pkt.data[pkt.off], pkt.len);
        }
 }
 
 static void
 kdp_poll(void)
 {
-       struct ether_header     *eh = NULL;
-       struct udpiphdr         aligned_ui, *ui = &aligned_ui;
-       struct ip               aligned_ip, *ip = &aligned_ip;
+       struct kdp_ether_header *eh = NULL;
+       struct kdp_udpiphdr     aligned_ui, *ui = &aligned_ui;
+       struct kdp_ip           aligned_ip, *ip = &aligned_ip;
        static int              msg_printed;
 
        if (pkt.input)
@@ -679,29 +899,26 @@ kdp_poll(void)
        }
 
        pkt.off = pkt.len = 0;
-       (*kdp_en_recv_pkt)(pkt.data, &pkt.len, 3/* ms */);
+       kdp_receive_data(pkt.data, &pkt.len, 3/* ms */);
 
        if (pkt.len == 0)
                return;
 
-       if (pkt.len >= sizeof(struct ether_header))
-       {
-               eh = (struct ether_header *)&pkt.data[pkt.off];  
+       if (pkt.len >= sizeof(struct kdp_ether_header)) {
+               eh = (struct kdp_ether_header *)&pkt.data[pkt.off];  
        
-               if (kdp_flag & KDP_ARP)
-               {
-                       if (ntohs(eh->ether_type) == ETHERTYPE_ARP)
-                       {
+               if (kdp_flag & KDP_ARP) {
+                       if (ntohs(eh->ether_type) == ETHERTYPE_ARP) {
                                kdp_arp_dispatch();
                                return;
                        }
                }
        }
 
-       if (pkt.len < (sizeof (struct ether_header) + sizeof (struct udpiphdr)))
+       if (pkt.len < (sizeof (struct kdp_ether_header) + sizeof (struct kdp_udpiphdr)))
                return;
 
-       pkt.off += (unsigned int)sizeof (struct ether_header);
+       pkt.off += (unsigned int)sizeof (struct kdp_ether_header);
        if (ntohs(eh->ether_type) != ETHERTYPE_IP) {
                return;
        }
@@ -710,16 +927,16 @@ kdp_poll(void)
        bcopy((char *)&pkt.data[pkt.off], (char *)ui, sizeof(*ui));
        bcopy((char *)&pkt.data[pkt.off], (char *)ip, sizeof(*ip));
 #else
-       ui = (struct udpiphdr *)&pkt.data[pkt.off];
-       ip = (struct ip *)&pkt.data[pkt.off];
+       ui = (struct kdp_udpiphdr *)&pkt.data[pkt.off];
+       ip = (struct kdp_ip *)&pkt.data[pkt.off];
 #endif
 
-       pkt.off += (unsigned int)sizeof (struct udpiphdr);
+       pkt.off += (unsigned int)sizeof (struct kdp_udpiphdr);
        if (ui->ui_pr != IPPROTO_UDP) {
                return;
        }
  
-       if (ip->ip_hl > (sizeof (struct ip) >> 2)) {
+       if (ip->ip_hl > (sizeof (struct kdp_ip) >> 2)) {
                return;
        }
 
@@ -736,8 +953,7 @@ kdp_poll(void)
         * enter the debugger if not told otherwise. 
         */
        else
-               if (flag_panic_dump_in_progress)
-               {
+               if (flag_panic_dump_in_progress) {
                        if (!flag_dont_abort_panic_dump) {
                                abort_panic_transfer();
                        }
@@ -755,10 +971,11 @@ kdp_poll(void)
        /*
         * Calculate kdp packet length.
         */
-       pkt.len = ntohs((u_short)ui->ui_ulen) - (unsigned int)sizeof (struct udphdr);
+       pkt.len = ntohs((u_short)ui->ui_ulen) - (unsigned int)sizeof (struct kdp_udphdr);
        pkt.input = TRUE;
 }
 
+
 /* Create and transmit an ARP resolution request for the target IP address.
  * This is modeled on ether_inet_arp()/RFC 826.
  */
@@ -766,8 +983,8 @@ kdp_poll(void)
 static void
 transmit_ARP_request(uint32_t ip_addr)
 {
-       struct ether_header     *eh = (struct ether_header *) &pkt.data[0];
-       struct ether_arp        *ea = (struct ether_arp *) &pkt.data[sizeof(struct ether_header)];
+       struct kdp_ether_header *eh = (struct kdp_ether_header *) &pkt.data[0];
+       struct kdp_ether_arp    *ea = (struct kdp_ether_arp *) &pkt.data[sizeof(struct kdp_ether_header)];
 
        KDP_DEBUG("Transmitting ARP request\n");
        /* Populate the ether_header */
@@ -791,13 +1008,13 @@ transmit_ARP_request(uint32_t ip_addr)
        memcpy(ea->arp_spa, (void *) &kdp_current_ip_address, sizeof(kdp_current_ip_address));
 
        pkt.off = 0;
-       pkt.len = sizeof(struct ether_header) + sizeof(struct ether_arp);
+       pkt.len = sizeof(struct kdp_ether_header) + sizeof(struct kdp_ether_arp);
        /* Transmit */
-       (*kdp_en_send_pkt)(&pkt.data[pkt.off], pkt.len);
+       kdp_send_data(&pkt.data[pkt.off], pkt.len);
 }
 
 static boolean_t
-kdp_arp_resolve(uint32_t arp_target_ip, struct ether_addr *resolved_MAC)
+kdp_arp_resolve(uint32_t arp_target_ip, struct kdp_ether_addr *resolved_MAC)
 {
        int poll_count = 256; /* ~770 ms modulo broadcast/delayed traffic? */
        char tretries = 0;
@@ -829,113 +1046,114 @@ TRANSMIT_RETRY:
                return TRUE;
        }
        
-       if (!flag_panic_dump_in_progress || pkt.input) /* we received a debugging packet, bail*/
-       {
+       if (!flag_panic_dump_in_progress || pkt.input) { /* we received a debugging packet, bail*/
                printf("Received a debugger packet,transferring control to debugger\n");
                /* Indicate that we should wait in the debugger when we return */
                kdp_flag |= DBG_POST_CORE;
                pkt.input = FALSE;
                return FALSE;
-       }
-       else /* We timed out */
+       } else { /* We timed out */
                if (0 == poll_count) {
                        poll_count = 256;
                        goto TRANSMIT_RETRY;
                }
+       }
        return FALSE;
 }
 
 static void
 kdp_handler(
-    void       *saved_state
+       void    *saved_state
 )
 {
-    unsigned short             reply_port;
-    kdp_hdr_t                  aligned_hdr, *hdr = &aligned_hdr;
+       unsigned short          reply_port;
+       kdp_hdr_t               aligned_hdr, *hdr = &aligned_hdr;
+
+       kdp.saved_state = saved_state;  // see comment in kdp_raise_exception
 
-    kdp.saved_state = saved_state;  // see comment in kdp_raise_exception
+       do {
+               while (!pkt.input)
+                       kdp_poll();
 
-    do {
-       while (!pkt.input)
-           kdp_poll();
-                       
 #if DO_ALIGN
-       bcopy((char *)&pkt.data[pkt.off], (char *)hdr, sizeof(*hdr));
+               bcopy((char *)&pkt.data[pkt.off], (char *)hdr, sizeof(*hdr));
 #else
-       hdr = (kdp_hdr_t *)&pkt.data[pkt.off];
+               hdr = (kdp_hdr_t *)&pkt.data[pkt.off];
 #endif
 
-       // ignore replies -- we're not expecting them anyway.
-       if (hdr->is_reply) {
-           goto again;
-       }
-       
-       if (hdr->request == KDP_REATTACH)
-         exception_seq = hdr->seq;
-
-       // check for retransmitted request
-       if (hdr->seq == (exception_seq - 1)) {
-           /* retransmit last reply */
-           (*kdp_en_send_pkt)(&saved_reply.data[saved_reply.off],
-                           saved_reply.len);
-           goto again;
-       } else if ((hdr->seq != exception_seq) &&
-                   (hdr->request != KDP_CONNECT)) {
-           printf("kdp: bad sequence %d (want %d)\n",
-                       hdr->seq, exception_seq);
-           goto again;
-       }
-       
-       /* This is a manual side-channel to the main KDP protocol.
-        * A client like GDB/kgmacros can manually construct 
-        * a request, set the input flag, issue a dummy KDP request,
-        * and then manually collect the result
-        */
-       if (manual_pkt.input) {
-         kdp_hdr_t *manual_hdr = (kdp_hdr_t *)&manual_pkt.data;
-         unsigned short manual_port_unused = 0;
-         if (!manual_hdr->is_reply) {
-           /* process */
-           kdp_packet((unsigned char *)&manual_pkt.data,
-                      (int *)&manual_pkt.len,
-                      &manual_port_unused);
-         }
-         manual_pkt.input = 0;
-       }
+               // ignore replies -- we're not expecting them anyway.
+               if (hdr->is_reply) {
+                       goto again;
+               }
 
-       if (kdp_packet((unsigned char*)&pkt.data[pkt.off], 
-                       (int *)&pkt.len, 
-                       (unsigned short *)&reply_port)) {
-            boolean_t sideband = FALSE;
-
-            /* if it's an already connected error message, 
-             * send a sideband reply for that. for successful connects,
-             * make sure the sequence number is correct. */
-            if (hdr->request == KDP_CONNECT) {
-                kdp_connect_reply_t *rp = 
-                       (kdp_connect_reply_t *) &pkt.data[pkt.off];
-                kdp_error_t err = rp->error;
-
-                if (err == KDPERR_NO_ERROR) {
-                    exception_seq = hdr->seq;
-                } else if (err == KDPERR_ALREADY_CONNECTED) {
-                    sideband = TRUE;
-                }
-            } 
+               if (hdr->request == KDP_REATTACH)
+                       exception_seq = hdr->seq;
+
+               // check for retransmitted request
+               if (hdr->seq == (exception_seq - 1)) {
+                       /* retransmit last reply */
+                       kdp_send_data(&saved_reply.data[saved_reply.off],
+                                       saved_reply.len);
+                       goto again;
+               } else if ((hdr->seq != exception_seq) &&
+                               (hdr->request != KDP_CONNECT)) {
+                       printf("kdp: bad sequence %d (want %d)\n",
+                                       hdr->seq, exception_seq);
+                       goto again;
+               }
 
-           kdp_reply(reply_port, sideband);
-       }
+               /* This is a manual side-channel to the main KDP protocol.
+                * A client like GDB/kgmacros can manually construct 
+                * a request, set the input flag, issue a dummy KDP request,
+                * and then manually collect the result
+                */
+               if (manual_pkt.input) {
+                       kdp_hdr_t *manual_hdr = (kdp_hdr_t *)&manual_pkt.data;
+                       unsigned short manual_port_unused = 0;
+                       if (!manual_hdr->is_reply) {
+                               /* process */
+                               int packet_length = manual_pkt.len;
+                               kdp_packet((unsigned char *)&manual_pkt.data,
+                                               &packet_length,
+                                               &manual_port_unused);
+                               manual_pkt.len = packet_length;
+                       }
+                       manual_pkt.input = 0;
+               }
+
+               if (kdp_packet((unsigned char*)&pkt.data[pkt.off],
+                                       (int *)&pkt.len,
+                                       (unsigned short *)&reply_port)) {
+                       boolean_t sideband = FALSE;
+
+                       /* if it's an already connected error message,
+                        * send a sideband reply for that. for successful connects,
+                        * make sure the sequence number is correct. */
+                       if (hdr->request == KDP_CONNECT) {
+                               kdp_connect_reply_t *rp =
+                                       (kdp_connect_reply_t *) &pkt.data[pkt.off];
+                               kdp_error_t err = rp->error;
+
+                               if (err == KDPERR_NO_ERROR) {
+                                       exception_seq = hdr->seq;
+                               } else if (err == KDPERR_ALREADY_CONNECTED) {
+                                       sideband = TRUE;
+                               }
+                       }
+
+                       kdp_reply(reply_port, sideband);
+               }
 
 again:
-       pkt.input = FALSE;
-    } while (kdp.is_halted);
+               pkt.input = FALSE;
+       } while (kdp.is_halted);
 }
 
 static void
 kdp_connection_wait(void)
 {
        unsigned short          reply_port;
-       struct ether_addr       kdp_mac_addr = kdp_get_mac_addr();
+       struct kdp_ether_addr   kdp_mac_addr = kdp_get_mac_addr();
        unsigned int            ip_addr = ntohl(kdp_get_ip_address());
 
        /*
@@ -944,50 +1162,53 @@ kdp_connection_wait(void)
         * the panic.log
         */
 
-       printf( "ethernet MAC address: %02x:%02x:%02x:%02x:%02x:%02x\n",
-            kdp_mac_addr.ether_addr_octet[0] & 0xff,
-            kdp_mac_addr.ether_addr_octet[1] & 0xff,
-            kdp_mac_addr.ether_addr_octet[2] & 0xff,
-            kdp_mac_addr.ether_addr_octet[3] & 0xff,
-            kdp_mac_addr.ether_addr_octet[4] & 0xff,
-            kdp_mac_addr.ether_addr_octet[5] & 0xff);
-               
-       kprintf( "ethernet MAC address: %02x:%02x:%02x:%02x:%02x:%02x\n",
+       if (KDP_SERIAL_ENABLED()) {
+               printf("Using serial KDP.\n");
+               kprintf("Using serial KDP.\n");
+       } else {
+               printf("ethernet MAC address: %02x:%02x:%02x:%02x:%02x:%02x\n",
                        kdp_mac_addr.ether_addr_octet[0] & 0xff,
                        kdp_mac_addr.ether_addr_octet[1] & 0xff,
                        kdp_mac_addr.ether_addr_octet[2] & 0xff,
                        kdp_mac_addr.ether_addr_octet[3] & 0xff,
                        kdp_mac_addr.ether_addr_octet[4] & 0xff,
                        kdp_mac_addr.ether_addr_octet[5] & 0xff);
-               
-       printf( "ip address: %d.%d.%d.%d\n",
-            (ip_addr & 0xff000000) >> 24,
-            (ip_addr & 0xff0000) >> 16,
-            (ip_addr & 0xff00) >> 8,
-            (ip_addr & 0xff));
-            
-       kprintf( "ip address: %d.%d.%d.%d\n",
+
+               kprintf("ethernet MAC address: %02x:%02x:%02x:%02x:%02x:%02x\n",
+                       kdp_mac_addr.ether_addr_octet[0] & 0xff,
+                       kdp_mac_addr.ether_addr_octet[1] & 0xff,
+                       kdp_mac_addr.ether_addr_octet[2] & 0xff,
+                       kdp_mac_addr.ether_addr_octet[3] & 0xff,
+                       kdp_mac_addr.ether_addr_octet[4] & 0xff,
+                       kdp_mac_addr.ether_addr_octet[5] & 0xff);
+
+               printf("ip address: %d.%d.%d.%d\n",
                        (ip_addr & 0xff000000) >> 24,
                        (ip_addr & 0xff0000) >> 16,
                        (ip_addr & 0xff00) >> 8,
                        (ip_addr & 0xff));
+
+               kprintf("ip address: %d.%d.%d.%d\n",
+                       (ip_addr & 0xff000000) >> 24,
+                       (ip_addr & 0xff0000) >> 16,
+                       (ip_addr & 0xff00) >> 8,
+                       (ip_addr & 0xff));
+       }
             
        printf("\nWaiting for remote debugger connection.\n");
+       kprintf("\nWaiting for remote debugger connection.\n");
 
 
        if (reattach_wait == 0) {
-               if((kdp_flag & KDP_GETC_ENA) && (0 != kdp_getc()))
-               {
+               if((kdp_flag & KDP_GETC_ENA) && (0 != kdp_getc())) {
                        printf("Options.....    Type\n");
                        printf("------------    ----\n");
                        printf("continue....    'c'\n");
                        printf("reboot......    'r'\n");
-#if MACH_KDB
-                       printf("enter kdb...    'k'\n");
-#endif
                }
-       } else
+       } else {
                reattach_wait = 0;
+       }
     
        exception_seq = 0;
 
@@ -1004,15 +1225,7 @@ kdp_connection_wait(void)
                                        printf("Rebooting...\n");
                                        kdp_machine_reboot();
                                        break;
-#if MACH_KDB
-                               case 'k':
-                                       printf("calling kdb...\n");
-                                       if (kdp_call_kdb())
-                                               return;
-                                       else
-                                               printf("not implemented...\n");
-#endif
-                                       default:
+                               default:
                                        break;
                                }
                        }
@@ -1030,8 +1243,8 @@ kdp_connection_wait(void)
                }
                if (((hdr->request == KDP_CONNECT) || (hdr->request == KDP_REATTACH)) &&
                        !hdr->is_reply && (hdr->seq == exception_seq)) {
-                   if (kdp_packet((unsigned char *)&pkt.data[pkt.off], 
-                               (int *)&pkt.len, 
+                   if (kdp_packet((unsigned char *)&pkt.data[pkt.off],
+                               (int *)&pkt.len,
                                (unsigned short *)&reply_port))
                            kdp_reply(reply_port, FALSE);
                    if (hdr->request == KDP_REATTACH) {
@@ -1047,180 +1260,176 @@ kdp_connection_wait(void)
        if (current_debugger == KDP_CUR_DB)
                active_debugger=1;
        printf("Connected to remote debugger.\n");
+       kprintf("Connected to remote debugger.\n");
 }
 
 static void
 kdp_send_exception(
-    unsigned int               exception,
-    unsigned int               code,
-    unsigned int               subcode
+       unsigned int            exception,
+       unsigned int            code,
+       unsigned int            subcode
 )
 {
-    unsigned short             remote_port;
-    unsigned int               timeout_count = 100;
-    unsigned int                poll_timeout;
-
-    do {
-       pkt.off = sizeof (struct ether_header) + sizeof (struct udpiphdr);
-       kdp_exception((unsigned char *)&pkt.data[pkt.off], 
-                       (int *)&pkt.len, 
-                       (unsigned short *)&remote_port,
-                       (unsigned int)exception, 
-                       (unsigned int)code, 
-                       (unsigned int)subcode);
-
-       kdp_send(remote_port);
-    
-       poll_timeout = 50;
-       while(!pkt.input && poll_timeout)
-         {
-           kdp_poll();
-           poll_timeout--;
-         }
+       unsigned short          remote_port;
+       unsigned int            timeout_count = 100;
+       unsigned int            poll_timeout;
+
+       do {
+               pkt.off = sizeof (struct kdp_ether_header) + sizeof (struct kdp_udpiphdr);
+               kdp_exception((unsigned char *)&pkt.data[pkt.off],
+                               (int *)&pkt.len,
+                               (unsigned short *)&remote_port,
+                               (unsigned int)exception,
+                               (unsigned int)code,
+                               (unsigned int)subcode);
+
+               kdp_send(remote_port);
+
+               poll_timeout = 50;
+               while (!pkt.input && poll_timeout) {
+                       kdp_poll();
+                       poll_timeout--;
+               }
+
+               if (pkt.input) {
+                       if (!kdp_exception_ack(&pkt.data[pkt.off], pkt.len)) {
+                               pkt.input = FALSE;
+                       }
+               }
 
-       if (pkt.input) {
-           if (!kdp_exception_ack(&pkt.data[pkt.off], pkt.len)) {
                pkt.input = FALSE;
-           }
-       }
 
-       pkt.input = FALSE;
+               if (kdp.exception_ack_needed)
+                       kdp_us_spin(250000);
 
-       if (kdp.exception_ack_needed)
-           kdp_us_spin(250000);
+       } while (kdp.exception_ack_needed && timeout_count--);
 
-    } while (kdp.exception_ack_needed && timeout_count--);
-    
-    if (kdp.exception_ack_needed) {
-       // give up & disconnect
-       printf("kdp: exception ack timeout\n");
-       if (current_debugger == KDP_CUR_DB)
-       active_debugger=0;
-       kdp_reset();
-    }
+       if (kdp.exception_ack_needed) {
+               // give up & disconnect
+               printf("kdp: exception ack timeout\n");
+               if (current_debugger == KDP_CUR_DB)
+                       active_debugger=0;
+               kdp_reset();
+       }
 }
 
-void
-kdp_raise_exception(
-    unsigned int               exception,
-    unsigned int               code,
-    unsigned int               subcode,
-    void                       *saved_state
-)
+static void 
+kdp_debugger_loop(
+       unsigned int            exception,
+       unsigned int            code,
+       unsigned int            subcode,
+       void                    *saved_state)
 {
-    int                        index;
+       int                     index;
 
-    /* Was a system trace requested ? */
-    if (kdp_snapshot && (!panic_active()) && (panic_caller == 0)) {
-           stack_snapshot_ret = kdp_stackshot(stack_snapshot_pid,
-           stack_snapshot_buf, stack_snapshot_bufsize,
-           stack_snapshot_options, &stack_snapshot_bytes_traced);
-           return;
-    }
+       if (saved_state == 0) 
+               printf("kdp_raise_exception with NULL state\n");
 
-    disable_preemption();
+       index = exception;
+       if (exception != EXC_BREAKPOINT) {
+               if (exception > EXC_BREAKPOINT || exception < EXC_BAD_ACCESS) {
+                       index = 0;
+               }
+               printf("%s exception (%x,%x,%x)\n",
+                               exception_message[index],
+                               exception, code, subcode);
+       }
+
+       kdp_sync_cache();
 
-    if (saved_state == 0) 
-       printf("kdp_raise_exception with NULL state\n");
+       /* XXX WMG it seems that sometimes it doesn't work to let kdp_handler
+        * do this. I think the client and the host can get out of sync.
+        */
+       kdp.saved_state = saved_state;
+       kdp.kdp_cpu = cpu_number();
+       kdp.kdp_thread = current_thread();
 
-    index = exception;
-    if (exception != EXC_BREAKPOINT) {
-       if (exception > EXC_BREAKPOINT || exception < EXC_BAD_ACCESS) {
-           index = 0;
+       if (kdp_en_setmode)
+               (*kdp_en_setmode)(TRUE); /* enabling link mode */
+
+       if (pkt.input)
+               kdp_panic("kdp_raise_exception");
+
+       if (((kdp_flag & KDP_PANIC_DUMP_ENABLED)
+            || (kdp_flag & PANIC_LOG_DUMP)
+            || kdp_has_polled_corefile())
+           && (panicstr != (char *) 0)) {
+               kdp_panic_dump();
+               if (kdp_flag & REBOOT_POST_CORE)
+                       kdp_machine_reboot();
+       } else {
+               if ((kdp_flag & PANIC_CORE_ON_NMI) && (panicstr == (char *) 0)
+                       && !kdp.is_conn) {
+
+                       disable_debug_output = disableConsoleOutput = FALSE;
+                       kdp_panic_dump();
+                       if (kdp_flag & REBOOT_POST_CORE)
+                               kdp_machine_reboot();
+
+                       if (!(kdp_flag & DBG_POST_CORE))
+                               goto exit_debugger_loop;
+               }
        }
-       printf("%s exception (%x,%x,%x)\n",
-               exception_message[index],
-               exception, code, subcode);
-    }
-
-    kdp_sync_cache();
-
-    /* XXX WMG it seems that sometimes it doesn't work to let kdp_handler
-     * do this. I think the client and the host can get out of sync.
-     */
-    kdp.saved_state = saved_state;
-    kdp.kdp_cpu = cpu_number();
-    kdp.kdp_thread = current_thread();
-
-    if (pkt.input)
-       kdp_panic("kdp_raise_exception");
-
-           
-    if (((kdp_flag & KDP_PANIC_DUMP_ENABLED) || (kdp_flag & PANIC_LOG_DUMP))
-       && (panicstr != (char *) 0)) {
-           kdp_panic_dump();
-           if (kdp_flag & REBOOT_POST_CORE)
-                   kdp_machine_reboot();
-      }
-    else
-      if ((kdp_flag & PANIC_CORE_ON_NMI) && (panicstr == (char *) 0) &&
-         !kdp.is_conn) {
-
-       disable_debug_output = disableConsoleOutput = FALSE;
-       kdp_panic_dump();
-
-       if (!(kdp_flag & DBG_POST_CORE))
-         goto exit_raise_exception;
-      }
-
- again:
-    if (!kdp.is_conn)
-       kdp_connection_wait();
-    else {
-       kdp_send_exception(exception, code, subcode);
-       if (kdp.exception_ack_needed) {
-           kdp.exception_ack_needed = FALSE;
-           kdp_remove_all_breakpoints();
-           printf("Remote debugger disconnected.\n");
-         }
-      }
-
-    if (kdp.is_conn) {
-       kdp.is_halted = TRUE;           /* XXX */
-       kdp_handler(saved_state);
-       if (!kdp.is_conn)
-         {
-           kdp_remove_all_breakpoints();
-           printf("Remote debugger disconnected.\n");
-         }
-    }
-    /* Allow triggering a panic core dump when connected to the machine
-     * Continuing after setting kdp_trigger_core_dump should do the
-     * trick.
-     */
-
-    if (1 == kdp_trigger_core_dump) {
-       kdp_flag |= KDP_PANIC_DUMP_ENABLED;
-       kdp_panic_dump();
-       if (kdp_flag & REBOOT_POST_CORE)
-               kdp_machine_reboot();
-       kdp_trigger_core_dump = 0;
-      }
 
-/* Trigger a reboot if the user has set this flag through the
- * debugger.Ideally, this would be done through the HOSTREBOOT packet
- * in the protocol,but that will need gdb support,and when it's
- * available, it should work automatically.
- */
-    if (1 == flag_kdp_trigger_reboot) {
-           kdp_machine_reboot();
-           /* If we're still around, reset the flag */
-           flag_kdp_trigger_reboot = 0;
-    }
+again:
+       if (!kdp.is_conn) {
+               kdp_connection_wait();
+       } else {
+               kdp_send_exception(exception, code, subcode);
+               if (kdp.exception_ack_needed) {
+                       kdp.exception_ack_needed = FALSE;
+                       kdp_remove_all_breakpoints();
+                       printf("Remote debugger disconnected.\n");
+               }
+       }
+
+       if (kdp.is_conn) {
+               kdp.is_halted = TRUE;           /* XXX */
+               kdp_handler(saved_state);
+               if (!kdp.is_conn)
+               {
+                       kdp_remove_all_breakpoints();
+                       printf("Remote debugger disconnected.\n");
+               }
+       }
+       /* Allow triggering a panic core dump when connected to the machine
+        * Continuing after setting kdp_trigger_core_dump should do the
+        * trick.
+        */
+
+       if (1 == kdp_trigger_core_dump) {
+               kdp_flag |= KDP_PANIC_DUMP_ENABLED;
+               kdp_panic_dump();
+               if (kdp_flag & REBOOT_POST_CORE)
+                       kdp_machine_reboot();
+               kdp_trigger_core_dump = 0;
+       }
+
+       /* Trigger a reboot if the user has set this flag through the
+        * debugger.Ideally, this would be done through the HOSTREBOOT packet
+        * in the protocol,but that will need gdb support,and when it's
+        * available, it should work automatically.
+        */
+       if (1 == flag_kdp_trigger_reboot) {
+               kdp_machine_reboot();
+               /* If we're still around, reset the flag */
+               flag_kdp_trigger_reboot = 0;
+       }
 
-    if (kdp_reentry_deadline) {
-           kdp_schedule_debugger_reentry(kdp_reentry_deadline);
-           printf("Debugger re-entry scheduled in %d milliseconds\n", kdp_reentry_deadline);
-           kdp_reentry_deadline = 0;
-    }
+       if (kdp_reentry_deadline) {
+               kdp_schedule_debugger_reentry(kdp_reentry_deadline);
+               printf("Debugger re-entry scheduled in %d milliseconds\n", kdp_reentry_deadline);
+               kdp_reentry_deadline = 0;
+       }
 
-    kdp_sync_cache();
+       kdp_sync_cache();
 
-    if (reattach_wait == 1)
-      goto again;
+       if (reattach_wait == 1)
+               goto again;
 
-exit_raise_exception:
-    enable_preemption();
+exit_debugger_loop:
+       if (kdp_en_setmode)
+               (*kdp_en_setmode)(FALSE); /* link cleanup */
 }
 
 void
@@ -1229,37 +1438,37 @@ kdp_reset(void)
        kdp.reply_port = kdp.exception_port = 0;
        kdp.is_halted = kdp.is_conn = FALSE;
        kdp.exception_seq = kdp.conn_seq = 0;
-        kdp.session_key = 0;
+       kdp.session_key = 0;
+       pkt.input = manual_pkt.input = FALSE;
+       pkt.len = pkt.off = manual_pkt.len = 0;
 }
 
 struct corehdr *
 create_panic_header(unsigned int request, const char *corename, 
-    unsigned length, unsigned int block)
+                       unsigned length, unsigned int block)
 {
-       struct udpiphdr         aligned_ui, *ui = &aligned_ui;
-       struct ip               aligned_ip, *ip = &aligned_ip;
-       struct ether_header     *eh;
+       struct kdp_udpiphdr     aligned_ui, *ui = &aligned_ui;
+       struct kdp_ip           aligned_ip, *ip = &aligned_ip;
+       struct kdp_ether_header *eh;
        struct corehdr          *coreh;
        const char              *mode = "octet";
-       char                    modelen  = strlen(mode);
-#if defined(__LP64__)  
+       char                    modelen  = strlen(mode) + 1;
+
        size_t                  fmask_size = sizeof(KDP_FEATURE_MASK_STRING) + sizeof(kdp_crashdump_feature_mask);
-#else
-       size_t                  fmask_size = 0;
-#endif
-       pkt.off = sizeof (struct ether_header);
+
+       pkt.off = sizeof (struct kdp_ether_header);
        pkt.len = (unsigned int)(length + ((request == KDP_WRQ) ? modelen + fmask_size : 0) + 
-           (corename ? strlen(corename): 0) + sizeof(struct corehdr));
+       (corename ? (strlen(corename) + 1 ): 0) + sizeof(struct corehdr));
 
 #if DO_ALIGN
        bcopy((char *)&pkt.data[pkt.off], (char *)ui, sizeof(*ui));
 #else
-       ui = (struct udpiphdr *)&pkt.data[pkt.off];
+       ui = (struct kdp_udpiphdr *)&pkt.data[pkt.off];
 #endif
        ui->ui_next = ui->ui_prev = 0;
        ui->ui_x1 = 0;
        ui->ui_pr = IPPROTO_UDP;
-       ui->ui_len = htons((u_short)pkt.len + sizeof (struct udphdr));
+       ui->ui_len = htons((u_short)pkt.len + sizeof (struct kdp_udphdr));
        ui->ui_src.s_addr = (uint32_t)kdp_current_ip_address;
        /* Already in network byte order via inet_aton() */
        ui->ui_dst.s_addr = panic_server_ip;
@@ -1271,12 +1480,12 @@ create_panic_header(unsigned int request, const char *corename,
        bcopy((char *)ui, (char *)&pkt.data[pkt.off], sizeof(*ui));
        bcopy((char *)&pkt.data[pkt.off], (char *)ip, sizeof(*ip));
 #else
-       ip = (struct ip *)&pkt.data[pkt.off];
+       ip = (struct kdp_ip *)&pkt.data[pkt.off];
 #endif
-       ip->ip_len = htons(sizeof (struct udpiphdr) + pkt.len);
+       ip->ip_len = htons(sizeof (struct kdp_udpiphdr) + pkt.len);
        ip->ip_v = IPVERSION;
        ip->ip_id = htons(ip_id++);
-       ip->ip_hl = sizeof (struct ip) >> 2;
+       ip->ip_hl = sizeof (struct kdp_ip) >> 2;
        ip->ip_ttl = udp_ttl;
        ip->ip_sum = 0;
        ip->ip_sum = htons(~ip_sum((unsigned char *)ip, ip->ip_hl));
@@ -1284,15 +1493,14 @@ create_panic_header(unsigned int request, const char *corename,
        bcopy((char *)ip, (char *)&pkt.data[pkt.off], sizeof(*ip));
 #endif
     
-       pkt.len += (unsigned int)sizeof (struct udpiphdr);
+       pkt.len += (unsigned int)sizeof (struct kdp_udpiphdr);
 
-       pkt.off += (unsigned int)sizeof (struct udpiphdr);
+       pkt.off += (unsigned int)sizeof (struct kdp_udpiphdr);
   
        coreh = (struct corehdr *) &pkt.data[pkt.off];
        coreh->th_opcode = htons((u_short)request);
   
-       if (request == KDP_WRQ)
-       {
+       if (request == KDP_WRQ) {
                char *cp;
 
                cp = coreh->th_u.tu_rpl;
@@ -1300,41 +1508,39 @@ create_panic_header(unsigned int request, const char *corename,
                *cp++ = '\0';
                cp += strlcpy (cp, mode, KDP_MAXPACKET - strlen(corename));
                *cp++ = '\0';
-#if defined(__LP64__)
                cp += strlcpy(cp, KDP_FEATURE_MASK_STRING, sizeof(KDP_FEATURE_MASK_STRING));
                *cp++ = '\0'; /* Redundant */
                bcopy(&kdp_crashdump_feature_mask, cp, sizeof(kdp_crashdump_feature_mask));
-#endif
-       }
-       else
-       {
+               kdp_crashdump_pkt_size = KDP_LARGE_CRASHDUMP_PKT_SIZE;
+               PE_parse_boot_argn("kdp_crashdump_pkt_size", &kdp_crashdump_pkt_size, sizeof(kdp_crashdump_pkt_size));
+               cp += sizeof(kdp_crashdump_feature_mask);
+               *(uint32_t *)cp = htonl(kdp_crashdump_pkt_size);
+       } else {
                coreh->th_block = htonl((unsigned int) block);
        }
 
-       pkt.off -= (unsigned int)sizeof (struct udpiphdr);
-       pkt.off -= (unsigned int)sizeof (struct ether_header);
+       pkt.off -= (unsigned int)sizeof (struct kdp_udpiphdr);
+       pkt.off -= (unsigned int)sizeof (struct kdp_ether_header);
 
-       eh = (struct ether_header *)&pkt.data[pkt.off];
+       eh = (struct kdp_ether_header *)&pkt.data[pkt.off];
        enaddr_copy(&kdp_current_mac_address, eh->ether_shost);
        enaddr_copy(&destination_mac, eh->ether_dhost);
        eh->ether_type = htons(ETHERTYPE_IP);
     
-       pkt.len += (unsigned int)sizeof (struct ether_header);
+       pkt.len += (unsigned int)sizeof (struct kdp_ether_header);
        return coreh;
 }
 
-static int kdp_send_crashdump_seek(char *corename, uint64_t seek_off)
+static int
+kdp_send_crashdump_seek(char *corename, uint64_t seek_off)
 {
        int panic_error;
 
-#if defined(__LP64__)
        if (kdp_feature_large_crashdumps) {
                panic_error = kdp_send_crashdump_pkt(KDP_SEEK, corename, 
                                                     sizeof(seek_off),
                                                     &seek_off);
-       } else
-#endif
-       {
+       } else {
                uint32_t off = (uint32_t) seek_off;
                panic_error = kdp_send_crashdump_pkt(KDP_SEEK, corename, 
                                                     sizeof(off), &off);
@@ -1346,44 +1552,49 @@ static int kdp_send_crashdump_seek(char *corename, uint64_t seek_off)
                return panic_error;
        }
 
-       return 0;
+       return KERN_SUCCESS;
 }
 
-int kdp_send_crashdump_data(unsigned int request, char *corename,
-    uint64_t length, caddr_t txstart)
+int
+kdp_send_crashdump_data(unsigned int request, char *corename,
+                           uint64_t length, void * txstart)
 {
        int panic_error = 0;
 
-       while (length > 0) {
-               uint64_t chunk = MIN(SEGSIZE, length);
-               
+       while ((length > 0) || !txstart) {
+               uint64_t chunk = MIN(kdp_crashdump_pkt_size, length);
+
                panic_error = kdp_send_crashdump_pkt(request, corename, chunk,
-                                                    (caddr_t) txstart);
+                                                       txstart);
                if (panic_error < 0) {
                        printf ("kdp_send_crashdump_pkt failed with error %d\n", panic_error);
                        return panic_error;
                }
-
-               if (!(panic_block % 2000))
-                       kdb_printf_unbuffered(".");
-
-               txstart += chunk;
+               if (!txstart) break;
+               txstart = (void *)(((uintptr_t) txstart) + chunk);
                length  -= chunk;
        }
-       return 0;
+       return KERN_SUCCESS;
 }
 
+uint32_t kdp_crashdump_short_pkt;
+
 int
 kdp_send_crashdump_pkt(unsigned int request, char *corename, 
-    uint64_t length, void *panic_data)
+                       uint64_t length, void *panic_data)
 {
+       int poll_count;
        struct corehdr *th = NULL;
-       int poll_count = 2500;
-  
-       char rretries = 0, tretries = 0;
+       char rretries, tretries;
+
+       if (kdp_dump_start_time == 0) {
+               kdp_dump_start_time = mach_absolute_time();
+               kdp_superblock_dump_start_time = kdp_dump_start_time;
+       }
 
+       tretries = rretries = 0;
+       poll_count = KDP_CRASHDUMP_POLL_COUNT;
        pkt.off = pkt.len = 0;
-  
        if (request == KDP_WRQ) /* longer timeout for initial request */
                poll_count += 1000;
 
@@ -1406,27 +1617,34 @@ TRANSMIT_RETRY:
        th = create_panic_header(request, corename, (unsigned)length, panic_block);
 
        if (request == KDP_DATA) {
-               /* as all packets are SEGSIZE in length, the last packet
+               /* as all packets are kdp_crashdump_pkt_size in length, the last packet
                 * may end up with trailing bits. make sure that those
                 * bits aren't confusing. */
-               if (length < SEGSIZE)
-                       memset(th->th_data + length, 'X', 
-                               SEGSIZE - (uint32_t) length);
+               if (length < kdp_crashdump_pkt_size) {
+                       kdp_crashdump_short_pkt++;
+                       memset(th->th_data + length, 'Y', 
+                               kdp_crashdump_pkt_size - (uint32_t) length);
+               }
 
-               if (!kdp_machine_vm_read((mach_vm_address_t)(intptr_t)panic_data, (caddr_t) th->th_data, length)) {
-                       memset ((caddr_t) th->th_data, 'X', (size_t)length);
+               if (!kdp_machine_vm_read((mach_vm_address_t)(uintptr_t)panic_data, (caddr_t) th->th_data, length)) {
+                       uintptr_t next_page = round_page((uintptr_t)panic_data);
+                       memset((caddr_t) th->th_data, 'X', (size_t)length);
+                       if ((next_page - ((uintptr_t) panic_data)) < length) {
+                               uint64_t resid = length - (next_page - (intptr_t) panic_data);
+                               if (!kdp_machine_vm_read((mach_vm_address_t)(uintptr_t)next_page, (caddr_t) th->th_data + (length - resid), resid)) {
+                                       memset((caddr_t) th->th_data + (length - resid), 'X', (size_t)resid);
+                               }
+                       }
                }
        }
        else if (request == KDP_SEEK) {
-#if defined(__LP64__)
                if (kdp_feature_large_crashdumps)
                        *(uint64_t *) th->th_data = OSSwapHostToBigInt64((*(uint64_t *) panic_data));
                else
-#endif
-               *(unsigned int *) th->th_data = htonl(*(unsigned int *) panic_data);
+                       *(unsigned int *) th->th_data = htonl(*(unsigned int *) panic_data);
        }
 
-       (*kdp_en_send_pkt)(&pkt.data[pkt.off], pkt.len);
+       kdp_send_data(&pkt.data[pkt.off], pkt.len);
 
        /* Listen for the ACK */
 RECEIVE_RETRY:
@@ -1436,90 +1654,79 @@ RECEIVE_RETRY:
        }
 
        if (pkt.input) {
-    
                pkt.input = FALSE;
     
                th = (struct corehdr *) &pkt.data[pkt.off];
-#if    defined(__LP64__)
                if (request == KDP_WRQ) {
                        uint16_t opcode64 = ntohs(th->th_opcode);
                        uint16_t features64 = (opcode64 & 0xFF00)>>8;
                        if ((opcode64 & 0xFF) == KDP_ACK) {
                                kdp_feature_large_crashdumps = features64 & KDP_FEATURE_LARGE_CRASHDUMPS;
+                               if (features64 & KDP_FEATURE_LARGE_PKT_SIZE) {
+                                       kdp_feature_large_pkt_size = 1;
+                               }
+                               else {
+                                       kdp_feature_large_pkt_size = 0;
+                                       kdp_crashdump_pkt_size = 512;
+                               }
                                printf("Protocol features: 0x%x\n", (uint32_t) features64);
                                th->th_opcode = htons(KDP_ACK);
                        }
                }
-#endif
                if (ntohs(th->th_opcode) == KDP_ACK && ntohl(th->th_block) == panic_block) {
-               }
-               else
+               } else {
                        if (ntohs(th->th_opcode) == KDP_ERROR) {
                                printf("Panic server returned error %d, retrying\n", ntohl(th->th_code));
                                poll_count = 1000;
                                goto TRANSMIT_RETRY;
+                       } else if (ntohl(th->th_block) == (panic_block - 1)) {
+                               printf("RX retry ");
+                               if (++rretries > 1)
+                                       goto TRANSMIT_RETRY;
+                               else
+                                       goto RECEIVE_RETRY;
                        }
-                       else 
-                               if (ntohl(th->th_block) == (panic_block - 1)) {
-                                       printf("RX retry ");
-                                       if (++rretries > 1)
-                                               goto TRANSMIT_RETRY;
-                                       else
-                                               goto RECEIVE_RETRY;
-                               }
-       }
-       else
-               if (!flag_panic_dump_in_progress) /* we received a debugging packet, bail*/
-               {
+               }
+       } else if (!flag_panic_dump_in_progress) { /* we received a debugging packet, bail*/
                        printf("Received a debugger packet,transferring control to debugger\n");
                        /* Configure that if not set ..*/
                        kdp_flag |= DBG_POST_CORE;
                        return (-2);
-               }
-               else /* We timed out */
+               } else { /* We timed out */
                        if (0 == poll_count) {
                                poll_count = 1000;
                                kdp_us_spin ((tretries%4) * panic_timeout); /* capped linear backoff */
                                goto TRANSMIT_RETRY;
                        }
-  
-       panic_block++;
-  
-       if (request == KDP_EOF)
+               }
+
+       if (!(++panic_block % SBLOCKSZ)) {
+               uint64_t ctime;
+               kdb_printf_unbuffered(".");
+               ctime = mach_absolute_time();
+               kdp_superblock_dump_time = ctime - kdp_superblock_dump_start_time;
+               kdp_superblock_dump_start_time = ctime;
+               if (kdp_superblock_dump_time > kdp_max_superblock_dump_time)
+                       kdp_max_superblock_dump_time = kdp_superblock_dump_time;
+               if (kdp_superblock_dump_time < kdp_min_superblock_dump_time)
+                       kdp_min_superblock_dump_time = kdp_superblock_dump_time;
+       }
+
+       if (request == KDP_EOF) {
                printf("\nTotal number of packets transmitted: %d\n", panic_block);
-  
-       return 1;
+               printf("Avg. superblock transfer abstime 0x%llx\n", ((mach_absolute_time() - kdp_dump_start_time) / panic_block) * SBLOCKSZ);
+               printf("Minimum superblock transfer abstime: 0x%llx\n", kdp_min_superblock_dump_time);
+               printf("Maximum superblock transfer abstime: 0x%llx\n", kdp_max_superblock_dump_time);
+       }
+       return KERN_SUCCESS;
 }
 
 static int 
 isdigit (char c)
 {
-  return ((c > 47) && (c < 58));
-}
-/* From user mode Libc - this ought to be in a library */
-static char *
-strnstr(char *s, const char *find, size_t slen)
-{
-  char c, sc;
-  size_t len;
-  
-  if ((c = *find++) != '\0') {
-    len = strlen(find);
-    do {
-      do {
-       if ((sc = *s++) == '\0' || slen-- < 1)
-         return (NULL);
-      } while (sc != c);
-      if (len > slen)
-       return (NULL);
-    } while (strncmp(s, find, len) != 0);
-    s--;
-  }
-  return (s);
+       return ((c > 47) && (c < 58));
 }
 
-extern char version[];
-
 /* Horrid hack to extract xnu version if possible - a much cleaner approach
  * would be to have the integrator run a script which would copy the
  * xnu version into a string or an int somewhere at project submission
@@ -1538,8 +1745,9 @@ kdp_get_xnu_version(char *versionbuf)
        char *vptr;
 
        strlcpy(vstr, "custom", 10);
-       if (strlcpy(versionbuf, version, 95) < 95) {
-               versionpos = strnstr(versionbuf, "xnu-", 90);
+       if (kdp_machine_vm_read((mach_vm_address_t)(uintptr_t)version, versionbuf, 128)) {
+               versionbuf[127] = '\0';
+               versionpos = strnstr(versionbuf, "xnu-", 115);
                if (versionpos) {
                        strncpy(vstr, versionpos, sizeof(vstr));
                        vstr[sizeof(vstr)-1] = '\0';
@@ -1557,8 +1765,6 @@ kdp_get_xnu_version(char *versionbuf)
        return retval;
 }
 
-extern char *inet_aton(const char *cp, struct in_addr *pin);
-
 void
 kdp_set_dump_info(const uint32_t flags, const char *filename, 
                   const char *destipstr, const char *routeripstr,
@@ -1627,49 +1833,45 @@ kdp_set_dump_info(const uint32_t flags, const char *filename,
 }
 
 void
-kdp_get_dump_info(uint32_t *flags, char *filename, char *destipstr, 
-                  char *routeripstr, uint32_t *port)
+kdp_get_dump_info(kdp_dumpinfo_reply_t *rp)
 {
-       if (destipstr) {
+       if (rp->destip) {
                if (panicd_specified)
-                       strlcpy(destipstr, panicd_ip_str, 
+                       strlcpy(rp->destip, panicd_ip_str,
                                 sizeof(panicd_ip_str));
                else 
-                       destipstr[0] = '\0';
+                       rp->destip[0] = '\0';
        }
 
-       if (routeripstr) {
+       if (rp->routerip) {
                if (router_specified)
-                       strlcpy(routeripstr, router_ip_str,
+                       strlcpy(rp->routerip, router_ip_str,
                                 sizeof(router_ip_str));
                else
-                       routeripstr[0] = '\0';
+                       rp->routerip[0] = '\0';
        }
 
-       if (filename) {
+       if (rp->name) {
                if (corename_specified)
-                       strlcpy(filename, corename_str, 
+                       strlcpy(rp->name, corename_str,
                                 sizeof(corename_str));
                else 
-                       filename[0] = '\0';
+                       rp->name[0] = '\0';
 
        }
 
-       if (port) 
-               *port = panicd_port;
-
-       if (flags) {
-               *flags = 0;
-                if (!panicd_specified) 
-                       *flags |= KDP_DUMPINFO_DISABLE;
-                else if (kdp_flag & PANIC_LOG_DUMP)
-                       *flags |= KDP_DUMPINFO_PANICLOG;
-               else
-                       *flags |= KDP_DUMPINFO_CORE;
+       rp->port = panicd_port;
 
-               if (noresume_on_disconnect)
-                       *flags |= KDP_DUMPINFO_NORESUME;
-       }
+       rp->type = 0;
+       if (!panicd_specified)
+               rp->type |= KDP_DUMPINFO_DISABLE;
+       else if (kdp_flag & PANIC_LOG_DUMP)
+               rp->type |= KDP_DUMPINFO_PANICLOG;
+       else
+               rp->type |= KDP_DUMPINFO_CORE;
+
+       if (noresume_on_disconnect)
+               rp->type |= KDP_DUMPINFO_NORESUME;
 }
 
 
@@ -1678,73 +1880,96 @@ void
 kdp_panic_dump(void)
 {
        char coreprefix[10];
+       char coresuffix[4];
        int panic_error;
 
-       uint64_t        abstime;
+       uint64_t        abstime;
        uint32_t        current_ip = ntohl((uint32_t)kdp_current_ip_address);
 
        if (flag_panic_dump_in_progress) {
-               printf("System dump aborted.\n");
+               kdb_printf("System dump aborted.\n");
                goto panic_dump_exit;
        }
                
        printf("Entering system dump routine\n");
-  
+
+       /* try a local disk dump */
+       if (kdp_has_polled_corefile()) {
+           flag_panic_dump_in_progress = TRUE;
+           kern_dump(KERN_DUMP_DISK);
+           abort_panic_transfer();
+       }
+
+       if (!strcmp("local", panicd_ip_str)) return;    /* disk only request */
+
+       if (!kdp_en_recv_pkt || !kdp_en_send_pkt) {
+               if (!kdp_has_polled_corefile()) {
+                   kdb_printf("Error: No transport device registered for kernel crashdump\n");
+               }
+               return;
+       }
+
        if (!panicd_specified) {
-               printf("A dump server was not specified in the boot-args, terminating kernel core dump.\n");
+               if (!kdp_has_polled_corefile()) {
+                   kdb_printf("A dump server was not specified in the boot-args, terminating kernel core dump.\n");
+                }
                goto panic_dump_exit;
        }
 
        flag_panic_dump_in_progress = TRUE;
-       not_in_kdp = 0;
 
        if (pkt.input)
                kdp_panic("kdp_panic_dump: unexpected pending input packet");
 
        kdp_get_xnu_version((char *) &pkt.data[0]);
 
-        if (!corename_specified) {
-            /* Panic log bit takes precedence over core dump bit */
-            if ((panicstr != (char *) 0) && (kdp_flag & PANIC_LOG_DUMP))
-               strlcpy(coreprefix, "paniclog", sizeof(coreprefix));
-            else if (kdp_flag & SYSTEM_LOG_DUMP) 
-               strlcpy(coreprefix, "systemlog", sizeof(coreprefix));
-           else
-               strlcpy(coreprefix, "core", sizeof(coreprefix));
-  
-            abstime = mach_absolute_time();
-           pkt.data[20] = '\0';
-           snprintf (corename_str, sizeof(corename_str), "%s-%s-%d.%d.%d.%d-%x", 
-                     coreprefix, &pkt.data[0],
-                     (current_ip & 0xff000000) >> 24,
-                     (current_ip & 0xff0000) >> 16,
-                     (current_ip & 0xff00) >> 8,
-                     (current_ip & 0xff),
-                     (unsigned int) (abstime & 0xffffffff));
-        }
+       if (!corename_specified) {
+               coresuffix[0] = 0;
+               /* Panic log bit takes precedence over core dump bit */
+               if ((panicstr != (char *) 0) && (kdp_flag & PANIC_LOG_DUMP))
+                       strlcpy(coreprefix, "paniclog", sizeof(coreprefix));
+               else if (kdp_flag & SYSTEM_LOG_DUMP)
+                       strlcpy(coreprefix, "systemlog", sizeof(coreprefix));
+               else {
+                       strlcpy(coreprefix, "core", sizeof(coreprefix));
+                       if (!kdp_corezip_disabled) strlcpy(coresuffix, ".gz", sizeof(coresuffix));
+               }
 
-       if (0 == inet_aton(panicd_ip_str, (struct in_addr *) &panic_server_ip)) {
-               printf("inet_aton() failed interpreting %s as a panic server IP\n", panicd_ip_str);
+               abstime = mach_absolute_time();
+               pkt.data[20] = '\0';
+               snprintf (corename_str,
+                               sizeof(corename_str),
+                               "%s-%s-%d.%d.%d.%d-%x%s",
+                               coreprefix, &pkt.data[0],
+                               (current_ip & 0xff000000) >> 24,
+                               (current_ip & 0xff0000) >> 16,
+                               (current_ip & 0xff00) >> 8,
+                               (current_ip & 0xff),
+                               (unsigned int) (abstime & 0xffffffff),
+                               coresuffix);
+       }
+
+       if (0 == inet_aton(panicd_ip_str, (struct kdp_in_addr *) &panic_server_ip)) {
+               kdb_printf("inet_aton() failed interpreting %s as a panic server IP\n", panicd_ip_str);
+       } else {
+               kdb_printf("Attempting connection to panic server configured at IP %s, port %d\n", panicd_ip_str, panicd_port);
        }
-       else
-               printf("Attempting connection to panic server configured at IP %s, port %d\n", panicd_ip_str, panicd_port);
 
        destination_mac = router_mac;
 
        if (kdp_arp_resolve(panic_server_ip, &temp_mac)) {
-               printf("Resolved %s's (or proxy's) link level address\n", panicd_ip_str);
+               kdb_printf("Resolved %s's (or proxy's) link level address\n", panicd_ip_str);
                destination_mac = temp_mac;
-       }
-       else {
+       } else {
                if (!flag_panic_dump_in_progress) goto panic_dump_exit;
                if (router_specified) {
-                       if (0 == inet_aton(router_ip_str, (struct in_addr *) &parsed_router_ip))
-                               printf("inet_aton() failed interpreting %s as an IP\n", router_ip_str);
-                       else {
+                       if (0 == inet_aton(router_ip_str, (struct kdp_in_addr *) &parsed_router_ip)) {
+                               kdb_printf("inet_aton() failed interpreting %s as an IP\n", router_ip_str);
+                       else {
                                router_ip = parsed_router_ip;
                                if (kdp_arp_resolve(router_ip, &temp_mac)) {
                                        destination_mac = temp_mac;
-                                       printf("Routing through specified router IP %s (%d)\n", router_ip_str, router_ip);
+                                       kdb_printf("Routing through specified router IP %s (%d)\n", router_ip_str, router_ip);
                                }
                        }
                }
@@ -1752,7 +1977,7 @@ kdp_panic_dump(void)
 
        if (!flag_panic_dump_in_progress) goto panic_dump_exit;
 
-       printf("Transmitting packets to link level address: %02x:%02x:%02x:%02x:%02x:%02x\n",
+       kdb_printf("Transmitting packets to link level address: %02x:%02x:%02x:%02x:%02x:%02x\n",
            destination_mac.ether_addr_octet[0] & 0xff,
            destination_mac.ether_addr_octet[1] & 0xff,
            destination_mac.ether_addr_octet[2] & 0xff,
@@ -1760,20 +1985,20 @@ kdp_panic_dump(void)
            destination_mac.ether_addr_octet[4] & 0xff,
            destination_mac.ether_addr_octet[5] & 0xff);
 
-       printf("Kernel map size is %llu\n", (unsigned long long) get_vmmap_size(kernel_map));
-       printf("Sending write request for %s\n", corename_str);  
+       kdb_printf("Kernel map size is %llu\n", (unsigned long long) get_vmmap_size(kernel_map));
+       kdb_printf("Sending write request for %s\n", corename_str);  
 
        if ((panic_error = kdp_send_crashdump_pkt(KDP_WRQ, corename_str, 0 , NULL)) < 0) {
-               printf ("kdp_send_crashdump_pkt failed with error %d\n", panic_error);
+               kdb_printf ("kdp_send_crashdump_pkt failed with error %d\n", panic_error);
                goto panic_dump_exit;
        }
 
        /* Just the panic log requested */
        if ((panicstr != (char *) 0) && (kdp_flag & PANIC_LOG_DUMP)) {
-               printf("Transmitting panic log, please wait: ");
+               kdb_printf_unbuffered("Transmitting panic log, please wait: ");
                kdp_send_crashdump_data(KDP_DATA, corename_str, 
-                                       debug_buf_ptr - debug_buf,
-                                       debug_buf);
+                                       debug_buf_ptr - debug_buf_addr,
+                                       debug_buf_addr);
                kdp_send_crashdump_pkt (KDP_EOF, NULL, 0, ((void *) 0));
                printf("Please file a bug report on this panic, if possible.\n");
                goto panic_dump_exit;
@@ -1784,15 +2009,13 @@ kdp_panic_dump(void)
                long start_off = msgbufp->msg_bufx;
                 long len;
 
-               printf("Transmitting system log, please wait: ");
+               kdb_printf_unbuffered("Transmitting system log, please wait: ");
                if (start_off >= msgbufp->msg_bufr) {
                        len = msgbufp->msg_size - start_off;
                        kdp_send_crashdump_data(KDP_DATA, corename_str, len, 
                                                msgbufp->msg_bufc + start_off);
-
                        /* seek to remove trailing bytes */
-                       if (len & (SEGSIZE - 1))
-                               kdp_send_crashdump_seek(corename_str, len);
+                       kdp_send_crashdump_seek(corename_str, len);
                        start_off  = 0;
                }
 
@@ -1807,12 +2030,10 @@ kdp_panic_dump(void)
         }
 
        /* We want a core dump if we're here */
-       kern_dump();
+       kern_dump(KERN_DUMP_NET);
 
 panic_dump_exit:
        abort_panic_transfer();
-       pkt.input = FALSE;
-       pkt.len = 0;
        kdp_reset();
        return;
 }
@@ -1822,7 +2043,6 @@ abort_panic_transfer(void)
 {
        flag_panic_dump_in_progress = FALSE;
        flag_dont_abort_panic_dump  = FALSE;
-       not_in_kdp = 1;
        panic_block = 0;
 }
 
@@ -1833,14 +2053,8 @@ static boolean_t needs_serial_init = TRUE;
 static void
 kdp_serial_send(void *rpkt, unsigned int rpkt_len)
 {
-       if (needs_serial_init)
-       {
-           serial_init();
-           needs_serial_init = FALSE;
-       }
-       
        //      printf("tx\n");
-       kdp_serialize_packet((unsigned char *)rpkt, rpkt_len, serial_putc);
+       kdp_serialize_packet((unsigned char *)rpkt, rpkt_len, pal_serial_putc_nocr);
 }
 
 static void 
@@ -1849,24 +2063,15 @@ kdp_serial_receive(void *rpkt, unsigned int *rpkt_len, unsigned int timeout)
        int readkar;
        uint64_t now, deadline;
        
-       if (needs_serial_init)
-       {
-           serial_init();
-           needs_serial_init = FALSE;
-       }
-       
        clock_interval_to_deadline(timeout, 1000 * 1000 /* milliseconds */, &deadline);
 
 //     printf("rx\n");
-       for(clock_get_uptime(&now); now < deadline; clock_get_uptime(&now))
-       {
-               readkar = serial_getc();
-               if(readkar >= 0)
-               {
+       for(clock_get_uptime(&now); now < deadline; clock_get_uptime(&now)) {
+               readkar = pal_serial_getc();
+               if(readkar >= 0) {
                        unsigned char *packet;
                        //                      printf("got char %02x\n", readkar);
-                       if((packet = kdp_unserialize_packet(readkar,rpkt_len)))
-                       {
+                       if((packet = kdp_unserialize_packet(readkar,rpkt_len))) {
                                memcpy(rpkt, packet, *rpkt_len);
                                return;
                        }
@@ -1875,26 +2080,44 @@ kdp_serial_receive(void *rpkt, unsigned int *rpkt_len, unsigned int timeout)
        *rpkt_len = 0;
 }
 
-static void kdp_serial_callout(__unused void *arg, kdp_event_t event)
+static boolean_t
+kdp_serial_setmode(boolean_t active)
 {
-    /* When we stop KDP, set the bit to re-initialize the console serial port
-     * the next time we send/receive a KDP packet.  We don't do it on
-     * KDP_EVENT_ENTER directly because it also gets called when we trap to KDP
-     * for non-external debugging, i.e., stackshot or core dumps.
-     *
-     * Set needs_serial_init on exit (and initialization, see above) and not
-     * enter because enter is sent multiple times and causes excess reinitialization.
-     */
-       
-    switch (event)
-    {
+       if (active == FALSE) /* leaving KDP */
+               return TRUE;
+
+       if (!needs_serial_init)
+               return TRUE;
+
+       pal_serial_init();
+       needs_serial_init = FALSE;
+       return TRUE;
+}
+
+
+static void 
+kdp_serial_callout(__unused void *arg, kdp_event_t event)
+{
+       /*
+        * When we stop KDP, set the bit to re-initialize the console serial
+        * port the next time we send/receive a KDP packet.  We don't do it on
+        * KDP_EVENT_ENTER directly because it also gets called when we trap to
+        * KDP for non-external debugging, i.e., stackshot or core dumps.
+        *
+        * Set needs_serial_init on exit (and initialization, see above) and not
+        * enter because enter is sent multiple times and causes excess
+        * reinitialization.
+        */
+
+       switch (event)
+       {
                case KDP_EVENT_PANICLOG:
                case KDP_EVENT_ENTER:
                        break;
                case KDP_EVENT_EXIT:
                        needs_serial_init = TRUE;
                        break;
-    }
+       }
 }
 
 #endif /* CONFIG_SERIAL_KDP */
@@ -1902,25 +2125,65 @@ static void kdp_serial_callout(__unused void *arg, kdp_event_t event)
 void
 kdp_init(void)
 {
+       strlcpy(kdp_kernelversion_string, version, sizeof(kdp_kernelversion_string));
+
+       /* Relies on platform layer calling panic_init() before kdp_init() */
+       if (kernel_uuid_string[0] != '\0') {
+               /*
+                * Update kdp_kernelversion_string with our UUID
+                * generated at link time.
+                */
+
+               strlcat(kdp_kernelversion_string, "; UUID=", sizeof(kdp_kernelversion_string));
+               strlcat(kdp_kernelversion_string, kernel_uuid_string, sizeof(kdp_kernelversion_string));
+       }
+
+       debug_log_init();
+
+#if defined(__x86_64__) || defined(__arm__) || defined(__arm64__)
+       if (vm_kernel_slide) {
+               char    KASLR_stext[19];
+               strlcat(kdp_kernelversion_string, "; stext=", sizeof(kdp_kernelversion_string));
+               snprintf(KASLR_stext, sizeof(KASLR_stext), "%p", (void *) vm_kernel_stext);
+               strlcat(kdp_kernelversion_string, KASLR_stext, sizeof(kdp_kernelversion_string));
+       }
+#endif
+
+       if (debug_boot_arg & DB_REBOOT_POST_CORE)
+               kdp_flag |= REBOOT_POST_CORE;
+#if    defined(__x86_64__)     
+       kdp_machine_init();
+#endif
+
+       kdp_timer_callout_init();
+       kdp_crashdump_feature_mask = htonl(kdp_crashdump_feature_mask);
+       kdp_core_init();
+
 #if CONFIG_SERIAL_KDP
        char kdpname[80];
-       struct in_addr ipaddr;
-       struct ether_addr macaddr;
+       struct kdp_in_addr ipaddr;
+       struct kdp_ether_addr macaddr;
 
+       boolean_t kdp_match_name_found = PE_parse_boot_argn("kdp_match_name", kdpname, sizeof(kdpname));
+       boolean_t kdp_not_serial = kdp_match_name_found ? (strncmp(kdpname, "serial", sizeof(kdpname))) : TRUE;
 
-#if CONFIG_EMBEDDED
-       //serial will be the debugger, unless match name is explicitly provided, and it's not "serial"
-       if(PE_parse_boot_argn("kdp_match_name", kdpname, sizeof(kdpname)) && strncmp(kdpname, "serial", sizeof(kdpname)) != 0)
+        // serial must be explicitly requested
+        if(!kdp_match_name_found || kdp_not_serial)
                return;
-#else
-       // serial must be explicitly requested
-       if(!PE_parse_boot_argn("kdp_match_name", kdpname, sizeof(kdpname)) || strncmp(kdpname, "serial", sizeof(kdpname)) != 0)
+
+#if WITH_CONSISTENT_DBG
+       if (kdp_not_serial && PE_consistent_debug_enabled() && debug_boot_arg) {
+               current_debugger = HW_SHM_CUR_DB;
                return;
-#endif
-       
-       kprintf("Intializing serial KDP\n");
+       } else {
+               printf("Serial requested, consistent debug disabled or debug boot arg not present, configuring debugging over serial\n");
+       }
+#endif /* WITH_CONSISTENT_DBG */
+
+       kprintf("Initializing serial KDP\n");
 
        kdp_register_callout(kdp_serial_callout, NULL);
+        kdp_register_link(NULL, kdp_serial_setmode);
        kdp_register_send_receive(kdp_serial_send, kdp_serial_receive);
        
        /* fake up an ip and mac for early serial debugging */
@@ -1930,7 +2193,123 @@ kdp_init(void)
        macaddr.ether_addr_octet[3] = 'i';
        macaddr.ether_addr_octet[4] = 'a';
        macaddr.ether_addr_octet[5] = 'l';
-       ipaddr.s_addr = 0xABADBABE;
+       ipaddr.s_addr = KDP_SERIAL_IPADDR;
        kdp_set_ip_and_mac_addresses(&ipaddr, &macaddr);
+        
 #endif /* CONFIG_SERIAL_KDP */
 }
+
+#else /* CONFIG_KDP_INTERACTIVE_DEBUGGING */
+void
+kdp_init(void) 
+{
+}
+#endif /* CONFIG_KDP_INTERACTIVE_DEBUGGING */
+
+#if   !CONFIG_KDP_INTERACTIVE_DEBUGGING
+__attribute__((noreturn))
+static void
+panic_spin_forever()
+{
+       kdb_printf("\nPlease go to https://panic.apple.com to report this panic\n");
+
+       for (;;) { }
+}
+#endif
+
+#if WITH_CONSISTENT_DBG && CONFIG_KDP_INTERACTIVE_DEBUGGING
+__attribute__((noreturn))
+static void
+panic_spin_shmcon()
+{
+       kdb_printf("\nPlease go to https://panic.apple.com to report this panic\n");
+       kdb_printf("Waiting for hardware shared memory debugger, handshake structure is at virt: %p, phys %p\n",
+                       hwsd_info, (void *)kvtophys((vm_offset_t)hwsd_info));
+
+       assert(hwsd_info != NULL);
+       hwsd_info->xhsdci_status = XHSDCI_STATUS_KERNEL_READY;
+       hwsd_info->xhsdci_seq_no = 0;
+       FlushPoC_DcacheRegion((vm_offset_t) hwsd_info, sizeof(*hwsd_info));
+
+       for (;;) {
+               FlushPoC_DcacheRegion((vm_offset_t) hwsd_info, sizeof(*hwsd_info));
+               if (hwsd_info->xhsdci_status == XHSDCI_COREDUMP_BEGIN) {
+                       kern_dump(KERN_DUMP_HW_SHMEM_DBG);
+               }
+
+               if ((hwsd_info->xhsdci_status == XHSDCI_COREDUMP_REMOTE_DONE) ||
+                               (hwsd_info->xhsdci_status == XHSDCI_COREDUMP_ERROR)) {
+                       hwsd_info->xhsdci_status = XHSDCI_STATUS_KERNEL_READY;
+                       hwsd_info->xhsdci_seq_no = 0;
+                       FlushPoC_DcacheRegion((vm_offset_t) hwsd_info, sizeof(*hwsd_info));
+               }
+       }
+}
+#endif /* WITH_CONSISTENT_DBG && CONFIG_KDP_INTERACTIVE_DEBUGGING */
+
+#if !CONFIG_KDP_INTERACTIVE_DEBUGGING
+__attribute__((noreturn))
+void
+kdp_raise_exception(
+               __unused unsigned int           exception,
+               __unused unsigned int           code,
+               __unused unsigned int           subcode,
+               __unused void                   *saved_state
+               )
+#else
+void
+kdp_raise_exception(
+               unsigned int            exception,
+               unsigned int            code,
+               unsigned int            subcode,
+               void                    *saved_state
+               )
+#endif
+{
+
+#if CONFIG_KDP_INTERACTIVE_DEBUGGING
+
+       unsigned int    initial_not_in_kdp = not_in_kdp;
+       not_in_kdp = 0;
+
+       disable_preemption();
+
+       if (current_debugger != KDP_CUR_DB) {
+               /* try a local disk dump */
+               if (kdp_has_polled_corefile()) {
+#if WITH_CONSISTENT_DBG
+                       if (current_debugger == HW_SHM_CUR_DB) {
+                               hwsd_info->xhsdci_status = XHSDCI_STATUS_KERNEL_BUSY;
+                       }
+#endif /* WITH_CONSISTENT_DBG */
+                       flag_panic_dump_in_progress = TRUE;
+                       kern_dump(KERN_DUMP_DISK);
+                       abort_panic_transfer();
+               }
+#if WITH_CONSISTENT_DBG
+               if (current_debugger == HW_SHM_CUR_DB) {
+                       panic_spin_shmcon();
+               }
+#endif /* WITH_CONSISTENT_DBG */
+
+
+               if (!panicDebugging) {
+                       kdp_machine_reboot();
+               }
+       }
+
+       kdp_debugger_loop(exception, code, subcode, saved_state);
+       not_in_kdp = initial_not_in_kdp;
+       enable_preemption();
+#else /* CONFIG_KDP_INTERACTIVE_DEBUGGING */
+       assert(current_debugger != KDP_CUR_DB);
+
+       /*
+        * If kernel debugging is enabled via boot-args, but KDP debugging
+        * is not compiled into the kernel, spin here waiting for debugging
+        * via another method.  Why here?  Because we want to have watchdog
+        * disabled (via KDP callout) while sitting waiting to be debugged.
+        */
+       panic_spin_forever();
+#endif /* CONFIG_KDP_INTERACTIVE_DEBUGGING */
+}