diff -upN /dev/null current/Documentation/i386/kgdb/kgdbeth.txt
--- /dev/null 2004-02-24 15:23:11.000000000 -0800
+++ current/Documentation/i386/kgdb/kgdbeth.txt 2004-05-09 13:43:52.000000000 -0700
@@ -0,0 +1,92 @@
+KGDB over ethernet
+==================
+
+Authors
+-------
+
+Robert Walsh <rjwalsh@durables.org> (2.6 port)
+wangdi <wangdi@clusterfs.com> (2.6 port)
+Matt Mackall <mpm@selenic.com> (netpoll api)
+San Mehat (original 2.4 code)
+
+
+Introduction
+------------
+
+KGDB supports debugging over ethernet (kgdboe) via polling of a given
+network interface. Most cards should be supported automatically.
+Debugging facilities are available as soon as the network driver and
+kgdboe have initialized. Unfortunately, this is too late in the boot
+process for debugging some issues, but works quite well for many
+others. This should not interfere with normal network usage and
+doesn't require a dedicated NIC.
+
+Terminology
+-----------
+
+This document uses the following terms:
+
+ TARGET: the machine being debugged.
+ HOST: the machine running gdb.
+
+
+Usage
+-----
+
+You need to use the following command-line option on the TARGET kernel:
+
+ kgdboe=[tgt-port]@<tgt-ip>/[dev],[host-port]@<host-ip>/[host-macaddr]
+
+ where
+ tgt-port source for UDP packets (defaults to 6443)
+ tgt-ip source IP to use (interface address)
+ dev network interface (eth0)
+ host-port HOST UDP port (6442) (not really used)
+ host-ip IP address for HOST machine
+ host-macaddr ethernet MAC address for HOST (ff:ff:ff:ff:ff:ff)
+
+ examples:
+
+ kgdboe=7000@192.168.0.1/eth1,7001@192.168.0.2/00:05:3C:04:47:5D
+ this machine is 192.168.0.1 on eth1
+ remote machine is 192.168.0.2 with MAC address 00:05:3C:04:47:5D
+ listen for gdb packets on port 7000
+ send unsolicited gdb packets to port 7001
+
+ kgdboe=@192.168.0.1/,@192.168.0.2/
+ this machine is 192.168.0.1 on default interface eth0
+ remote machine is 192.168.0.2, use default broadcast MAC address
+ listen for gdb packets on default port 6443
+ send unsolicited gdb packets to port 6442
+
+Only packets originating from the configured HOST IP address will be
+accepted by the debugger.
+
+On the HOST side, run gdb as normal and use a remote UDP host as the
+target:
+
+ % gdb ./vmlinux
+ GNU gdb Red Hat Linux (5.3post-0.20021129.18rh)
+ Copyright 2003 Free Software Foundation, Inc.
+ GDB is free software, covered by the GNU General Public License, and you are
+ welcome to change it and/or distribute copies of it under certain conditions.
+ Type "show copying" to see the conditions.
+ There is absolutely no warranty for GDB. Type "show warranty" for details.
+ This GDB was configured as "i386-redhat-linux-gnu"...
+ (gdb) target remote udp:HOSTNAME:6443
+
+You can now continue as if you were debugging over a serial line.
+
+Limitations
+-----------
+
+The current release of this code is exclusive of using kgdb on a
+serial interface, so you must boot without the kgdboe option to use
+serial debugging. Trying to debug the network driver while using it
+will prove interesting.
+
+Bug reports
+-----------
+
+Send bug reports to Robert Walsh <rjwalsh@durables.org> and Matt
+Mackall <mpm@selenic.com>.
diff -upN reference/arch/i386/kernel/irq.c current/arch/i386/kernel/irq.c
--- reference/arch/i386/kernel/irq.c 2004-04-30 11:23:02.000000000 -0700
+++ current/arch/i386/kernel/irq.c 2004-05-09 13:43:52.000000000 -0700
@@ -570,6 +570,8 @@ out:
irq_exit();
+ kgdb_process_breakpoint();
+
return 1;
}
diff -upN reference/arch/i386/kernel/kgdb_stub.c current/arch/i386/kernel/kgdb_stub.c
--- reference/arch/i386/kernel/kgdb_stub.c 2004-05-09 13:43:51.000000000 -0700
+++ current/arch/i386/kernel/kgdb_stub.c 2004-05-09 13:43:52.000000000 -0700
@@ -30,6 +30,8 @@
*
* Written by: Glenn Engel $
* Updated by: David Grothe <dave@gcom.com>
+ * Updated by: Robert Walsh <rjwalsh@durables.org>
+ * Updated by: wangdi <wangdi@clusterfs.com>
* ModuleState: Experimental $
*
* NOTES: See Below $
@@ -49,6 +51,10 @@
* support for ia-32(x86) hardware debugging.
* Amit S. Kale ( akale@veritas.com )
*
+ * Modified to support debugging over ethernet by Robert Walsh
+ * <rjwalsh@durables.org> and wangdi <wangdi@clusterfs.com>, based on
+ * code by San Mehat.
+ *
*
* To enable debugger support, two things need to happen. One, a
* call to set_debug_traps() is necessary in order to allow any breakpoints
@@ -112,6 +118,8 @@
#include <asm/processor.h>
#include <linux/irq.h>
#include <asm/desc.h>
+#include <linux/inet.h>
+#include <linux/netpoll.h>
/************************************************************************
*
@@ -122,8 +130,12 @@ typedef void (*Function) (void); /* poin
/* Thread reference */
typedef unsigned char threadref[8];
-extern void putDebugChar(int); /* write a single character */
-extern int getDebugChar(void); /* read and return a single char */
+extern int tty_putDebugChar(int); /* write a single character */
+extern int tty_getDebugChar(void); /* read and return a single char */
+extern void tty_flushDebugChar(void); /* flush pending characters */
+extern int eth_putDebugChar(int); /* write a single character */
+extern int eth_getDebugChar(void); /* read and return a single char */
+extern void eth_flushDebugChar(void); /* flush pending characters */
/************************************************************************/
/* BUFMAX defines the maximum number of characters in inbound/outbound buffers*/
@@ -264,6 +276,41 @@ malloc(int size)
}
/*
+ * I/O dispatch functions...
+ * Based upon kgdboe, either call the ethernet
+ * handler or the serial one..
+ */
+void
+putDebugChar(int c)
+{
+ if (!kgdboe) {
+ tty_putDebugChar(c);
+ } else {
+ eth_putDebugChar(c);
+ }
+}
+
+int
+getDebugChar(void)
+{
+ if (!kgdboe) {
+ return tty_getDebugChar();
+ } else {
+ return eth_getDebugChar();
+ }
+}
+
+void
+flushDebugChar(void)
+{
+ if (!kgdboe) {
+ tty_flushDebugChar();
+ } else {
+ eth_flushDebugChar();
+ }
+}
+
+/*
* Gdb calls functions by pushing agruments, including a return address
* on the stack and the adjusting EIP to point to the function. The
* whole assumption in GDB is that we are on a different stack than the
@@ -429,6 +476,7 @@ getpacket(char *buffer)
if (remote_debug)
printk("R:%s\n", buffer);
+ flushDebugChar();
}
/* send the packet in buffer. */
@@ -441,25 +489,67 @@ putpacket(char *buffer)
char ch;
/* $<packet info>#<checksum>. */
- do {
- if (remote_debug)
- printk("T:%s\n", buffer);
- putDebugChar('$');
- checksum = 0;
- count = 0;
- while ((ch = buffer[count])) {
- putDebugChar(ch);
- checksum += ch;
- count += 1;
- }
+ if (!kgdboe) {
+ do {
+ if (remote_debug)
+ printk("T:%s\n", buffer);
+ putDebugChar('$');
+ checksum = 0;
+ count = 0;
+
+ while ((ch = buffer[count])) {
+ putDebugChar(ch);
+ checksum += ch;
+ count += 1;
+ }
+
+ putDebugChar('#');
+ putDebugChar(hexchars[checksum >> 4]);
+ putDebugChar(hexchars[checksum % 16]);
+ flushDebugChar();
+
+ } while ((getDebugChar() & 0x7f) != '+');
+ } else {
+ /*
+ * For udp, we can not transfer too much bytes once.
+ * We only transfer MAX_SEND_COUNT size bytes each time
+ */
- putDebugChar('#');
- putDebugChar(hexchars[checksum >> 4]);
- putDebugChar(hexchars[checksum % 16]);
+#define MAX_SEND_COUNT 30
- } while ((getDebugChar() & 0x7f) != '+');
+ int send_count = 0, i = 0;
+ char send_buf[MAX_SEND_COUNT];
+ do {
+ if (remote_debug)
+ printk("T:%s\n", buffer);
+ putDebugChar('$');
+ checksum = 0;
+ count = 0;
+ send_count = 0;
+ while ((ch = buffer[count])) {
+ if (send_count >= MAX_SEND_COUNT) {
+ for(i = 0; i < MAX_SEND_COUNT; i++) {
+ putDebugChar(send_buf[i]);
+ }
+ flushDebugChar();
+ send_count = 0;
+ } else {
+ send_buf[send_count] = ch;
+ checksum += ch;
+ count ++;
+ send_count++;
+ }
+ }
+ for(i = 0; i < send_count; i++)
+ putDebugChar(send_buf[i]);
+ putDebugChar('#');
+ putDebugChar(hexchars[checksum >> 4]);
+ putDebugChar(hexchars[checksum % 16]);
+ flushDebugChar();
+ } while ((getDebugChar() & 0x7f) != '+');
+ }
}
static char remcomInBuffer[BUFMAX];
@@ -1047,9 +1137,9 @@ in_kgdb(struct pt_regs *regs)
*/
in_kgdb_entry_log[cpu]++;
in_kgdb_here_log[cpu] = regs;
- if (cpu == spinlock_cpu || waiting_cpus[cpu].task) {
+ if (cpu == spinlock_cpu || waiting_cpus[cpu].task)
goto exit_in_kgdb;
- }
+
/*
* For protection of the initilization of the spin locks by kgdb
* it locks the kgdb spinlock before it gets the wait locks set
@@ -1058,16 +1148,18 @@ in_kgdb(struct pt_regs *regs)
* sequence where the wait lock is removed prior to the kgdb lock
* so if kgdb gets unlocked, we just exit.
*/
+
while (spin_is_locked(&kgdb_spinlock) &&
!spin_is_locked(waitlocks + cpu)) ;
- if (!spin_is_locked(&kgdb_spinlock)) {
+ if (!spin_is_locked(&kgdb_spinlock))
goto exit_in_kgdb;
- }
+
waiting_cpus[cpu].task = current;
waiting_cpus[cpu].pid = (current->pid) ? : (PID_MAX + cpu);
waiting_cpus[cpu].regs = regs;
spin_unlock_wait(waitlocks + cpu);
+
/*
* log departure of this cpu
*/
@@ -1179,6 +1271,12 @@ kgdb_handle_exception(int exceptionVecto
print_regs(®s);
return (0);
}
+ /*
+ * If we're using eth mode, set the 'mode' in the netdevice.
+ */
+
+ if (kgdboe)
+ netpoll_set_trap(1);
kgdb_local_irq_save(flags);
@@ -1233,10 +1331,12 @@ kgdb_handle_exception(int exceptionVecto
if (num_online_cpus() > 1) {
int me_in_kgdb = in_kgdb_entry_log[smp_processor_id()];
smp_send_nmi_allbutself();
+
while (i < num_online_cpus() && time != end_time) {
int j;
for (j = 0; j < MAX_NO_CPUS; j++) {
if (waiting_cpus[j].task &&
+ waiting_cpus[j].task != NOCPU &&
!cpu_logged_in[j]) {
i++;
cpu_logged_in[j] = 1;
@@ -1625,6 +1725,10 @@ kgdb_handle_exception(int exceptionVecto
}
}
}
+
+ if (kgdboe)
+ netpoll_set_trap(0);
+
correct_hw_break();
asm volatile ("movl %0, %%db6\n"::"r" (0));
goto exit_kgdb;
@@ -2330,3 +2434,23 @@ kgdb_tstamp(int line, char *source, int
typedef int gdb_debug_hook(int exceptionVector,
int signo, int err_code, struct pt_regs *linux_regs);
gdb_debug_hook *linux_debug_hook = &kgdb_handle_exception; /* histerical reasons... */
+
+static int kgdb_need_breakpoint[NR_CPUS];
+
+void kgdb_schedule_breakpoint(void)
+{
+ kgdb_need_breakpoint[smp_processor_id()] = 1;
+}
+
+void kgdb_process_breakpoint(void)
+{
+ /*
+ * Handle a breakpoint queued from inside network driver code
+ * to avoid reentrancy issues
+ */
+ if (kgdb_need_breakpoint[smp_processor_id()]) {
+ kgdb_need_breakpoint[smp_processor_id()] = 0;
+ BREAKPOINT;
+ }
+}
+
diff -upN reference/arch/i386/lib/kgdb_serial.c current/arch/i386/lib/kgdb_serial.c
--- reference/arch/i386/lib/kgdb_serial.c 2004-05-09 13:43:51.000000000 -0700
+++ current/arch/i386/lib/kgdb_serial.c 2004-05-09 13:43:52.000000000 -0700
@@ -4,6 +4,9 @@
* Written (hacked together) by David Grothe (dave@gcom.com)
* Modified to allow invokation early in boot see also
* kgdb.h for instructions by George Anzinger(george@mvista.com)
+ * Modified to handle debugging over ethernet by Robert Walsh
+ * <rjwalsh@durables.org> and wangdi <wangdi@clusterfs.com>, based on
+ * code by San Mehat.
*
*/
@@ -155,12 +158,12 @@ write_char(struct async_struct *info, in
* It will receive a limited number of characters of input
* from the gdb host machine and save them up in a buffer.
*
- * When the gdb stub routine getDebugChar() is called it
+ * When the gdb stub routine tty_getDebugChar() is called it
* draws characters out of the buffer until it is empty and
* then reads directly from the serial port.
*
* We do not attempt to write chars from the interrupt routine
- * since the stubs do all of that via putDebugChar() which
+ * since the stubs do all of that via tty_putDebugChar() which
* writes one byte after waiting for the interface to become
* ready.
*
@@ -226,7 +229,7 @@ extern char *kgdb_version;
/*
* Hook an IRQ for KGDB.
*
- * This routine is called from putDebugChar, below.
+ * This routine is called from tty_putDebugChar, below.
*/
static int ints_disabled = 1;
int
@@ -331,7 +334,7 @@ program_uart(struct async_struct *info)
}
/*
- * getDebugChar
+ * tty_getDebugChar
*
* This is a GDB stub routine. It waits for a character from the
* serial interface and then returns it. If there is no serial
@@ -345,11 +348,11 @@ extern spinlock_t kgdb_spinlock;
/* Caller takes needed protections */
int
-getDebugChar(void)
+tty_getDebugChar(void)
{
volatile int chr, dum, time, end_time;
- dbprintk(("getDebugChar(port %x): ", gdb_async_info->port));
+ dbprintk(("tty_getDebugChar(port %x): ", gdb_async_info->port));
if (gdb_async_info == NULL) {
gdb_hook_interrupt(&local_info, 0);
@@ -375,7 +378,7 @@ getDebugChar(void)
dbprintk(("%c\n", chr > ' ' && chr < 0x7F ? chr : ' '));
return (chr);
-} /* getDebugChar */
+} /* tty_getDebugChar */
static int count = 3;
static spinlock_t one_at_atime = SPIN_LOCK_UNLOCKED;
@@ -383,6 +386,9 @@ static spinlock_t one_at_atime = SPIN_LO
static int __init
kgdb_enable_ints(void)
{
+ if (kgdboe) {
+ return 0;
+ }
if (gdb_async_info == NULL) {
gdb_hook_interrupt(&local_info, 1);
}
@@ -444,7 +450,7 @@ kgdb_enable_ints_now(void)
}
/*
- * putDebugChar
+ * tty_putDebugChar
*
* This is a GDB stub routine. It waits until the interface is ready
* to transmit a char and then sends it. If there is no serial
@@ -452,9 +458,9 @@ kgdb_enable_ints_now(void)
* pretended to send the char. Caller takes needed protections.
*/
void
-putDebugChar(int chr)
+tty_putDebugChar(int chr)
{
- dbprintk(("putDebugChar(port %x): chr=%02x '%c', ints_on=%d\n",
+ dbprintk(("tty_putDebugChar(port %x): chr=%02x '%c', ints_on=%d\n",
gdb_async_info->port,
chr,
chr > ' ' && chr < 0x7F ? chr : ' ', ints_disabled ? 0 : 1));
@@ -480,6 +486,14 @@ putDebugChar(int chr)
}
}
-} /* putDebugChar */
+} /* tty_putDebugChar */
+
+/*
+ * This does nothing for the serial port, since it doesn't buffer.
+ */
+
+void tty_flushDebugChar(void)
+{
+}
module_init(kgdb_enable_ints);
diff -upN reference/drivers/net/Makefile current/drivers/net/Makefile
--- reference/drivers/net/Makefile 2004-04-30 11:23:22.000000000 -0700
+++ current/drivers/net/Makefile 2004-05-09 13:43:52.000000000 -0700
@@ -189,4 +189,6 @@ obj-$(CONFIG_NET_TULIP) += tulip/
obj-$(CONFIG_HAMRADIO) += hamradio/
obj-$(CONFIG_IRDA) += irda/
+# Must come after all NICs that might use them
obj-$(CONFIG_NETCONSOLE) += netconsole.o
+obj-$(CONFIG_KGDB) += kgdb_eth.o
diff -upN /dev/null current/drivers/net/kgdb_eth.c
--- /dev/null 2004-02-24 15:23:11.000000000 -0800
+++ current/drivers/net/kgdb_eth.c 2004-05-09 13:43:52.000000000 -0700
@@ -0,0 +1,131 @@
+/*
+ * Network interface GDB stub
+ *
+ * Written by San Mehat (nettwerk@biodome.org)
+ * Based upon 'gdbserial' by David Grothe (dave@gcom.com)
+ * and Scott Foehner (sfoehner@engr.sgi.com)
+ *
+ * Twiddled for 2.6 by Robert Walsh <rjwalsh@durables.org>
+ * and wangdi <wangdi@clusterfs.com>.
+ *
+ * Refactored for netpoll API by Matt Mackall <mpm@selenic.com>
+ *
+ */
+
+#include <linux/sched.h>
+#include <linux/interrupt.h>
+#include <linux/config.h>
+#include <linux/string.h>
+#include <linux/netpoll.h>
+
+#include <asm/system.h>
+#include <asm/kgdb.h>
+#include <asm/io.h>
+#include <asm/bitops.h>
+#include <asm/system.h>
+#include <asm/irq.h>
+#include <asm/atomic.h>
+
+#define IN_BUF_SIZE 512 /* power of 2, please */
+#define OUT_BUF_SIZE 256
+
+static char in_buf[IN_BUF_SIZE], out_buf[OUT_BUF_SIZE];
+static int in_head, in_tail, out_count;
+static atomic_t in_count;
+int kgdboe = 0; /* Default to tty mode */
+
+extern void set_debug_traps(void);
+extern void breakpoint(void);
+static void rx_hook(struct netpoll *np, int port, char *msg, int len);
+
+static struct netpoll np = {
+ .name = "kgdboe",
+ .dev_name = "eth0",
+ .rx_hook = rx_hook,
+ .local_port = 6443,
+ .remote_port = 6442,
+ .remote_mac = {0xff, 0xff, 0xff, 0xff, 0xff, 0xff},
+};
+
+int eth_getDebugChar(void)
+{
+ int chr;
+
+ while (atomic_read(&in_count) == 0)
+ netpoll_poll(&np);
+
+ chr = in_buf[in_tail++];
+ in_tail &= (IN_BUF_SIZE - 1);
+ atomic_dec(&in_count);
+ return chr;
+}
+
+void eth_flushDebugChar(void)
+{
+ if(out_count && np.dev) {
+ netpoll_send_udp(&np, out_buf, out_count);
+ out_count = 0;
+ }
+}
+
+void eth_putDebugChar(int chr)
+{
+ out_buf[out_count++] = chr;
+ if(out_count == OUT_BUF_SIZE)
+ eth_flushDebugChar();
+}
+
+static void rx_hook(struct netpoll *np, int port, char *msg, int len)
+{
+ int i;
+
+ np->remote_port = port;
+
+ /* Is this gdb trying to attach? */
+ if (!netpoll_trap() && len == 8 && !strncmp(msg, "$Hc-1#09", 8))
+ kgdb_schedule_breakpoint();
+
+ for (i = 0; i < len; i++) {
+ if (msg[i] == 3)
+ kgdb_schedule_breakpoint();
+
+ if (atomic_read(&in_count) >= IN_BUF_SIZE) {
+ /* buffer overflow, clear it */
+ in_head = in_tail = 0;
+ atomic_set(&in_count, 0);
+ break;
+ }
+ in_buf[in_head++] = msg[i];
+ in_head &= (IN_BUF_SIZE - 1);
+ atomic_inc(&in_count);
+ }
+}
+
+static int option_setup(char *opt)
+{
+ return netpoll_parse_options(&np, opt);
+}
+
+__setup("kgdboe=", option_setup);
+
+static int init_kgdboe(void)
+{
+#ifdef CONFIG_SMP
+ if (num_online_cpus() > CONFIG_NO_KGDB_CPUS) {
+ printk("kgdb: too manu cpus. Cannot enable debugger with more than %d cpus\n", CONFIG_NO_KGDB_CPUS);
+ return -1;
+ }
+#endif
+
+ set_debug_traps();
+
+ if(!np.remote_ip || netpoll_setup(&np))
+ return 1;
+
+ kgdboe = 1;
+ printk(KERN_INFO "kgdb: debugging over ethernet enabled\n");
+
+ return 0;
+}
+
+module_init(init_kgdboe);
diff -upN reference/include/asm-i386/kgdb.h current/include/asm-i386/kgdb.h
--- reference/include/asm-i386/kgdb.h 2004-05-09 13:43:52.000000000 -0700
+++ current/include/asm-i386/kgdb.h 2004-05-09 13:43:52.000000000 -0700
@@ -18,6 +18,14 @@ extern void breakpoint(void);
#ifndef BREAKPOINT
#define BREAKPOINT asm(" int $3")
#endif
+
+extern void kgdb_schedule_breakpoint(void);
+extern void kgdb_process_breakpoint(void);
+
+extern int kgdb_tty_hook(void);
+extern int kgdb_eth_hook(void);
+extern int kgdboe;
+
/*
* GDB debug stub (or any debug stub) can point the 'linux_debug_hook'
* pointer to its routine and it will be entered as the first thing
@@ -55,5 +63,7 @@ void kgdb_tstamp(int line, char *source,
#define kgdb_handle_exception
#define breakpoint
#define INIT_KGDB_INTS
+#define kgdb_process_breakpoint() do {} while(0)
+
#endif
#endif /* __KGDB */
diff -upN reference/net/Kconfig current/net/Kconfig
--- reference/net/Kconfig 2004-04-30 11:23:57.000000000 -0700
+++ current/net/Kconfig 2004-05-09 13:43:52.000000000 -0700
@@ -650,18 +650,17 @@ endmenu
endmenu
+config KGDBOE
+ def_bool X86 && KGDB
+
config NETPOLL
- def_bool NETCONSOLE
+ def_bool NETCONSOLE || KGDBOE
config NETPOLL_RX
- bool "Netpoll support for trapping incoming packets"
- default n
- depends on NETPOLL
+ def_bool KGDBOE
config NETPOLL_TRAP
- bool "Netpoll traffic trapping"
- default n
- depends on NETPOLL
+ def_bool KGDBOE
config NET_POLL_CONTROLLER
def_bool NETPOLL
diff -upN reference/net/core/dev.c current/net/core/dev.c
--- reference/net/core/dev.c 2004-04-30 11:23:58.000000000 -0700
+++ current/net/core/dev.c 2004-05-09 13:43:52.000000000 -0700
@@ -1523,7 +1523,6 @@ static void sample_queue(unsigned long d
}
#endif
-
/**
* netif_rx - post buffer to the network code
* @skb: buffer to post
@@ -1843,7 +1842,6 @@ static void net_rx_action(struct softirq
unsigned long start_time = jiffies;
int budget = netdev_max_backlog;
-
local_irq_disable();
while (!list_empty(&queue->poll_list)) {
@@ -1869,6 +1867,8 @@ static void net_rx_action(struct softirq
dev_put(dev);
local_irq_disable();
}
+
+ kgdb_process_breakpoint();
}
out:
local_irq_enable();