From: Jim Houston The attached patch updates my kgdb-x86_64-support.patch to work with linux-2.6.2-rc1-mm3. The conflicts seen with the old patch are the result of Andi Kleen pushing a portion of the patch to Linus. In particular my addition of .cfi directives to the x86_64 assembly files is now in Linus's tree. This version has also been tested (and now works) with Matt Mackall's kgdb over ethernet. DESC kgdb-x86_64-warning-fixes EDESC DESC kgdb-x86_64-fix EDESC DESC kgdb-x86_64-serial-fix EDESC DESC kprobes exception notifier fix EDESC From: Prasanna S Panchamukhi This patch modifies the return value of kprobes exceptions notify handler. The kprobes exception notifier returns NOTIFY_STOP on handling notification. This patch helps other debuggers to co-exists with the Kprobes. Other debuggers registered for exceptions notification must return NOTIFY_STOP on handling the notification. Signed-Off-By : Prasanna S Panchamukhi DESC kgdb-x86_64-support fix EDESC From: Jim Houston Andi's change for a single debug notifier is fine, but the earlier addition of DIE_PAGE_FAULT broke the kgdb stub in Andrew's -mm tree. The attached patch fixes this problem by ignoring this notification for page faults. DESC kgdb CONFIG_DEBUG_INFO fix EDESC From: Adrian Bunk Why does everyone think one DEBUG_INFO wasn't enough? Signed-off-by: Adrian Bunk Signed-off-by: Andrew Morton --- x86_64/Kconfig | 0 Makefile | 1 arch/x86_64/Kconfig.debug | 3 arch/x86_64/Kconfig.kgdb | 171 ++ arch/x86_64/boot/compressed/head.S | 1 arch/x86_64/boot/compressed/misc.c | 1 arch/x86_64/kernel/Makefile | 1 arch/x86_64/kernel/irq.c | 2 arch/x86_64/kernel/kgdb_stub.c | 2593 +++++++++++++++++++++++++++++++++++++ arch/x86_64/kernel/smp.c | 12 arch/x86_64/kernel/traps.c | 3 arch/x86_64/lib/Makefile | 1 arch/x86_64/lib/kgdb_serial.c | 490 ++++++ include/asm-x86_64/kgdb.h | 71 + include/asm-x86_64/kgdb_local.h | 102 + include/linux/config.h | 2 init/main.c | 2 serial/8250.c | 0 18 files changed, 3449 insertions(+), 7 deletions(-) diff -puN arch/x86_64/boot/compressed/head.S~kgdb-x86_64-support arch/x86_64/boot/compressed/head.S --- devel/arch/x86_64/boot/compressed/head.S~kgdb-x86_64-support 2005-07-26 00:38:32.000000000 -0700 +++ devel-akpm/arch/x86_64/boot/compressed/head.S 2005-07-26 00:38:32.000000000 -0700 @@ -24,7 +24,6 @@ .code32 .text -#define IN_BOOTLOADER #include #include #include diff -puN arch/x86_64/boot/compressed/misc.c~kgdb-x86_64-support arch/x86_64/boot/compressed/misc.c --- devel/arch/x86_64/boot/compressed/misc.c~kgdb-x86_64-support 2005-07-26 00:38:32.000000000 -0700 +++ devel-akpm/arch/x86_64/boot/compressed/misc.c 2005-07-26 00:38:32.000000000 -0700 @@ -9,7 +9,6 @@ * High loaded stuff by Hans Lermen & Werner Almesberger, Feb. 1996 */ -#define IN_BOOTLOADER #include "miscsetup.h" #include #include diff -puN arch/x86_64/Kconfig~kgdb-x86_64-support arch/x86_64/Kconfig diff -puN /dev/null arch/x86_64/Kconfig.kgdb --- /dev/null 2003-09-15 06:40:47.000000000 -0700 +++ devel-akpm/arch/x86_64/Kconfig.kgdb 2005-07-26 00:38:32.000000000 -0700 @@ -0,0 +1,171 @@ +config KGDB + bool "Include kgdb kernel debugger" + depends on DEBUG_KERNEL + select DEBUG_INFO + help + If you say Y here, the system will be compiled with the debug + option (-g) and a debugging stub will be included in the + kernel. This stub communicates with gdb on another (host) + computer via a serial port. The host computer should have + access to the kernel binary file (vmlinux) and a serial port + that is connected to the target machine. Gdb can be made to + configure the serial port or you can use stty and setserial to + do this. See the 'target' command in gdb. This option also + configures in the ability to request a breakpoint early in the + boot process. To request the breakpoint just include 'kgdb' + as a boot option when booting the target machine. The system + will then break as soon as it looks at the boot options. This + option also installs a breakpoint in panic and sends any + kernel faults to the debugger. For more information see the + Documentation/i386/kgdb.txt file. + +choice + depends on KGDB + prompt "Debug serial port BAUD" + default KGDB_115200BAUD + help + Gdb and the kernel stub need to agree on the baud rate to be + used. Some systems (x86 family at this writing) allow this to + be configured. + +config KGDB_9600BAUD + bool "9600" + +config KGDB_19200BAUD + bool "19200" + +config KGDB_38400BAUD + bool "38400" + +config KGDB_57600BAUD + bool "57600" + +config KGDB_115200BAUD + bool "115200" +endchoice + +config KGDB_PORT + hex "hex I/O port address of the debug serial port" + depends on KGDB + default 3f8 + help + Some systems (x86 family at this writing) allow the port + address to be configured. The number entered is assumed to be + hex, don't put 0x in front of it. The standard address are: + COM1 3f8 , irq 4 and COM2 2f8 irq 3. Setserial /dev/ttySx + will tell you what you have. It is good to test the serial + connection with a live system before trying to debug. + +config KGDB_IRQ + int "IRQ of the debug serial port" + depends on KGDB + default 4 + help + This is the irq for the debug port. If everything is working + correctly and the kernel has interrupts on a control C to the + port should cause a break into the kernel debug stub. + +config KGDB_MORE + bool "Add any additional compile options" + depends on KGDB + default n + help + Saying yes here turns on the ability to enter additional + compile options. + + +config KGDB_OPTIONS + depends on KGDB_MORE + string "Additional compile arguments" + default "-O1" + help + This option allows you enter additional compile options for + the whole kernel compile. Each platform will have a default + that seems right for it. For example on PPC "-ggdb -O1", and + for i386 "-O1". Note that by configuring KGDB "-g" is already + turned on. In addition, on i386 platforms + "-fomit-frame-pointer" is deleted from the standard compile + options. + +config NO_KGDB_CPUS + int "Number of CPUs" + depends on KGDB && SMP + default NR_CPUS + help + + This option sets the number of cpus for kgdb ONLY. It is used + to prune some internal structures so they look "nice" when + displayed with gdb. This is to overcome possibly larger + numbers that may have been entered above. Enter the real + number to get nice clean kgdb_info displays. + +config KGDB_TS + bool "Enable kgdb time stamp macros?" + depends on KGDB + default n + help + Kgdb event macros allow you to instrument your code with calls + to the kgdb event recording function. The event log may be + examined with gdb at a break point. Turning on this + capability also allows you to choose how many events to + keep. Kgdb always keeps the lastest events. + +choice + depends on KGDB_TS + prompt "Max number of time stamps to save?" + default KGDB_TS_128 + +config KGDB_TS_64 + bool "64" + +config KGDB_TS_128 + bool "128" + +config KGDB_TS_256 + bool "256" + +config KGDB_TS_512 + bool "512" + +config KGDB_TS_1024 + bool "1024" + +endchoice + +config STACK_OVERFLOW_TEST + bool "Turn on kernel stack overflow testing?" + depends on KGDB + default n + help + This option enables code in the front line interrupt handlers + to check for kernel stack overflow on interrupts and system + calls. This is part of the kgdb code on x86 systems. + +config KGDB_CONSOLE + bool "Enable serial console thru kgdb port" + depends on KGDB + default n + help + This option enables the command line "console=kgdb" option. + When the system is booted with this option in the command line + all kernel printk output is sent to gdb (as well as to other + consoles). For this to work gdb must be connected. For this + reason, this command line option will generate a breakpoint if + gdb has not yet connected. After the gdb continue command is + given all pent up console output will be printed by gdb on the + host machine. Neither this option, nor KGDB require the + serial driver to be configured. + +config KGDB_SYSRQ + bool "Turn on SysRq 'G' command to do a break?" + depends on KGDB + default y + help + This option includes an option in the SysRq code that allows + you to enter SysRq G which generates a breakpoint to the KGDB + stub. This will work if the keyboard is alive and can + interrupt the system. Because of constraints on when the + serial port interrupt can be enabled, this code may allow you + to interrupt the system before the serial port control C is + available. Just say yes here. + diff -puN arch/x86_64/kernel/irq.c~kgdb-x86_64-support arch/x86_64/kernel/irq.c --- devel/arch/x86_64/kernel/irq.c~kgdb-x86_64-support 2005-07-26 00:38:32.000000000 -0700 +++ devel-akpm/arch/x86_64/kernel/irq.c 2005-07-26 00:38:32.000000000 -0700 @@ -103,7 +103,7 @@ asmlinkage unsigned int do_IRQ(struct pt __do_IRQ(irq, regs); irq_exit(); - + kgdb_process_breakpoint(); return 1; } diff -puN /dev/null arch/x86_64/kernel/kgdb_stub.c --- /dev/null 2003-09-15 06:40:47.000000000 -0700 +++ devel-akpm/arch/x86_64/kernel/kgdb_stub.c 2005-07-26 00:38:32.000000000 -0700 @@ -0,0 +1,2593 @@ +/* + * + * This program is free software; you can redistribute it and/or modify it + * under the terms of the GNU General Public License as published by the + * Free Software Foundation; either version 2, or (at your option) any + * later version. + * + * This program is distributed in the hope that it will be useful, but + * WITHOUT ANY WARRANTY; without even the implied warranty of + * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU + * General Public License for more details. + * + */ + +/* + * Copyright (c) 2000 VERITAS Software Corporation. + * + */ +/**************************************************************************** + * Header: remcom.c,v 1.34 91/03/09 12:29:49 glenne Exp $ + * + * Module name: remcom.c $ + * Revision: 1.34 $ + * Date: 91/03/09 12:29:49 $ + * Contributor: Lake Stevens Instrument Division$ + * + * Description: low level support for gdb debugger. $ + * + * Considerations: only works on target hardware $ + * + * Written by: Glenn Engel $ + * Updated by: David Grothe + * Updated by: Robert Walsh + * Updated by: wangdi + * ModuleState: Experimental $ + * + * NOTES: See Below $ + * + * Modified for 386 by Jim Kingdon, Cygnus Support. + * Compatibility with 2.1.xx kernel by David Grothe + * + * Changes to allow auto initilization. All that is needed is that it + * be linked with the kernel and a break point (int 3) be executed. + * The header file defines BREAKPOINT to allow one to do + * this. It should also be possible, once the interrupt system is up, to + * call putDebugChar("+"). Once this is done, the remote debugger should + * get our attention by sending a ^C in a packet. George Anzinger + * + * Integrated into 2.2.5 kernel by Tigran Aivazian + * Added thread support, support for multiple processors, + * support for ia-32(x86) hardware debugging. + * Amit S. Kale ( akale@veritas.com ) + * + * Modified to support debugging over ethernet by Robert Walsh + * and wangdi , based on + * code by San Mehat. + * + * X86_64 changes from Andi Kleen's patch merged by Jim Houston + * (jim.houston@ccur.com). If it works thank Andi if its broken + * blame me. + * + * To enable debugger support, two things need to happen. One, a + * call to set_debug_traps() is necessary in order to allow any breakpoints + * or error conditions to be properly intercepted and reported to gdb. + * Two, a breakpoint needs to be generated to begin communication. This + * is most easily accomplished by a call to breakpoint(). Breakpoint() + * simulates a breakpoint by executing an int 3. + * + ************* + * + * The following gdb commands are supported: + * + * command function Return value + * + * g return the value of the CPU registers hex data or ENN + * G set the value of the CPU registers OK or ENN + * + * mAA..AA,LLLL Read LLLL bytes at address AA..AA hex data or ENN + * MAA..AA,LLLL: Write LLLL bytes at address AA.AA OK or ENN + * + * c Resume at current address SNN ( signal NN) + * cAA..AA Continue at address AA..AA SNN + * + * s Step one instruction SNN + * sAA..AA Step one instruction from AA..AA SNN + * + * k kill + * + * ? What was the last sigval ? SNN (signal NN) + * + * All commands and responses are sent with a packet which includes a + * checksum. A packet consists of + * + * $#. + * + * where + * :: + * :: < two hex digits computed as modulo 256 sum of > + * + * When a packet is received, it is first acknowledged with either '+' or '-'. + * '+' indicates a successful transfer. '-' indicates a failed transfer. + * + * Example: + * + * Host: Reply: + * $m0,10#2a +$00010203040506070809101112131415#42 + * + ****************************************************************************/ +#define KGDB_VERSION "<20030915.1651.33>" +#include +#include +#include /* for strcpy */ +#include +#include +#include +#include /* for linux pt_regs struct */ +#include +#include +#include +#include +#include +#include +#include +#include +#include +#include +#include +#include +#include +#include + +#define Dearly_printk(x...) +int kgdb_enabled = 0; + +/************************************************************************ + * + * external low-level support routines + */ +typedef void (*Function) (void); /* pointer to a function */ + +/* Thread reference */ +typedef unsigned char threadref[8]; + +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*/ +/* at least NUMREGBYTES*2 are needed for register packets */ +/* Longer buffer is needed to list all threads */ +#define BUFMAX 400 + +char *kgdb_version = KGDB_VERSION; + +/* debug > 0 prints ill-formed commands in valid packets & checksum errors */ +int debug_regs = 0; /* set to non-zero to print registers */ + +/* filled in by an external module */ +char *gdb_module_offsets; + +static const char hexchars[] = "0123456789abcdef"; + +/* Number of bytes of registers. */ +#define NUMREGBYTES (NUMREGS * sizeof(unsigned long)) +/* + * Note that this register image is in a different order than + * the register image that Linux produces at interrupt time. + * + * Linux's register image is defined by struct pt_regs in ptrace.h. + * Just why GDB uses a different order is a historical mystery. + * + * Could add XMM and segment registers here. + */ +enum regnames {_RAX, + _RBX, + _RCX, + _RDX, + _RSI, + _RDI, + _RBP, + _RSP, + _R8, + _R9, + _R10, + _R11, + _R12, + _R13, + _R14, + _R15, + _PC, + _PS, + NUMREGS }; + + +/*************************** ASSEMBLY CODE MACROS *************************/ +/* + * Put the error code here just in case the user cares. + * Likewise, the vector number here (since GDB only gets the signal + * number through the usual means, and that's not very specific). + * The called_from is the return address so he can tell how we entered kgdb. + * This will allow him to seperate out the various possible entries. + */ +#define REMOTE_DEBUG 0 /* set != to turn on printing (also available in info) */ + +#define PID_MAX PID_MAX_DEFAULT + +#ifdef CONFIG_SMP +void smp_send_nmi_allbutself(void); +#define IF_SMP(x) x +#undef MAX_NO_CPUS +#ifndef CONFIG_NO_KGDB_CPUS +#define CONFIG_NO_KGDB_CPUS 2 +#endif +#if CONFIG_NO_KGDB_CPUS > NR_CPUS +#define MAX_NO_CPUS NR_CPUS +#else +#define MAX_NO_CPUS CONFIG_NO_KGDB_CPUS +#endif +#define hold_init hold_on_sstep: 1, +#define MAX_CPU_MASK (unsigned long)((1LL << MAX_NO_CPUS) - 1LL) +#define NUM_CPUS num_online_cpus() +#else +#define IF_SMP(x) +#define hold_init +#undef MAX_NO_CPUS +#define MAX_NO_CPUS 1 +#define NUM_CPUS 1 +#endif +#define NOCPU (struct task_struct *)0xbad1fbad +/* *INDENT-OFF* */ +struct kgdb_info { + int used_malloc; + void *called_from; + long long entry_tsc; + int errcode; + int vector; + int print_debug_info; +#ifdef CONFIG_SMP + int hold_on_sstep; + struct { + volatile struct task_struct *task; + int pid; + int hold; + struct pt_regs *regs; + } cpus_waiting[MAX_NO_CPUS]; +#endif +} kgdb_info = {hold_init print_debug_info:REMOTE_DEBUG, vector:-1}; + +/* *INDENT-ON* */ + +#define used_m kgdb_info.used_malloc +/* + * This is little area we set aside to contain the stack we + * need to build to allow gdb to call functions. We use one + * per cpu to avoid locking issues. We will do all this work + * with interrupts off so that should take care of the protection + * issues. + */ +#define LOOKASIDE_SIZE 200 /* should be more than enough */ +#define MALLOC_MAX 200 /* Max malloc size */ +struct { + unsigned long rsp; + unsigned long array[LOOKASIDE_SIZE]; +} fn_call_lookaside[MAX_NO_CPUS]; + +static int trap_cpu; +static unsigned long OLD_esp; + +#define END_OF_LOOKASIDE &fn_call_lookaside[trap_cpu].array[LOOKASIDE_SIZE] +#define IF_BIT 0x200 +#define TF_BIT 0x100 + +#define MALLOC_ROUND 8-1 + +static char malloc_array[MALLOC_MAX]; +IF_SMP(static void to_gdb(const char *mess)); +void * +malloc(int size) +{ + + if (size <= (MALLOC_MAX - used_m)) { + int old_used = used_m; + used_m += ((size + MALLOC_ROUND) & (~MALLOC_ROUND)); + return &malloc_array[old_used]; + } else { + return NULL; + } +} + +/* + * 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 + * one the "user" i.e. code that hit the break point, is on. This, of + * course is not true in the kernel. Thus various dodges are needed to + * do the call without directly messing with EIP (which we can not change + * as it is just a location and not a register. To adjust it would then + * require that we move every thing below EIP up or down as needed. This + * will not work as we may well have stack relative pointer on the stack + * (such as the pointer to regs, for example). + + * So here is what we do: + * We detect gdb attempting to store into the stack area and instead, store + * into the fn_call_lookaside.array at the same relative location as if it + * were the area ESP pointed at. We also trap ESP modifications + * and uses these to adjust fn_call_lookaside.esp. On entry + * fn_call_lookaside.esp will be set to point at the last entry in + * fn_call_lookaside.array. This allows us to check if it has changed, and + * if so, on exit, we add the registers we will use to do the move and a + * trap/ interrupt return exit sequence. We then adjust the eflags in the + * regs array (remember we now have a copy in the fn_call_lookaside.array) to + * kill the interrupt bit, AND we change EIP to point at our set up stub. + * As part of the register set up we preset the registers to point at the + * begining and end of the fn_call_lookaside.array, so all the stub needs to + * do is move words from the array to the stack until ESP= the desired value + * then do the rti. This will then transfer to the desired function with + * all the correct registers. Nifty huh? + */ +extern asmlinkage void fn_call_stub(void); +extern asmlinkage void fn_rtn_stub(void); +/* *INDENT-OFF* */ +__asm__("fn_rtn_stub:\n\t" + "movq %rax,%rsp\n\t" + "fn_call_stub:\n\t" + "1:\n\t" + "addq $-8,%rbx\n\t" + "movq (%rbx), %rax\n\t" + "pushq %rax\n\t" + "cmpq %rsp,%rcx\n\t" + "jne 1b\n\t" + "popq %rax\n\t" + "popq %rbx\n\t" + "popq %rcx\n\t" + "iret \n\t"); +/* *INDENT-ON* */ +#define gdb_i386vector kgdb_info.vector +#define gdb_i386errcode kgdb_info.errcode +#define waiting_cpus kgdb_info.cpus_waiting +#define remote_debug kgdb_info.print_debug_info +#define hold_cpu(cpu) kgdb_info.cpus_waiting[cpu].hold +/* gdb locks */ + +#ifdef CONFIG_SMP +static int in_kgdb_called; +static spinlock_t waitlocks[MAX_NO_CPUS] = + {[0 ... MAX_NO_CPUS - 1] = SPIN_LOCK_UNLOCKED }; +/* + * The following array has the thread pointer of each of the "other" + * cpus. We make it global so it can be seen by gdb. + */ +volatile int in_kgdb_entry_log[MAX_NO_CPUS]; +volatile struct pt_regs *in_kgdb_here_log[MAX_NO_CPUS]; +/* +static spinlock_t continuelocks[MAX_NO_CPUS]; +*/ +spinlock_t kgdb_spinlock = SPIN_LOCK_UNLOCKED; +/* waiters on our spinlock plus us */ +static atomic_t spinlock_waiters = ATOMIC_INIT(1); +static int spinlock_count = 0; +static int spinlock_cpu = 0; +/* + * Note we use nested spin locks to account for the case where a break + * point is encountered when calling a function by user direction from + * kgdb. Also there is the memory exception recursion to account for. + * Well, yes, but this lets other cpus thru too. Lets add a + * cpu id to the lock. + */ +#define KGDB_SPIN_LOCK(x) if( spinlock_count == 0 || \ + spinlock_cpu != smp_processor_id()){\ + atomic_inc(&spinlock_waiters); \ + while (! spin_trylock(x)) {\ + in_kgdb(®s);\ + }\ + atomic_dec(&spinlock_waiters); \ + spinlock_count = 1; \ + spinlock_cpu = smp_processor_id(); \ + }else{ \ + spinlock_count++; \ + } +#define KGDB_SPIN_UNLOCK(x) if( --spinlock_count == 0) spin_unlock(x) +#else +unsigned kgdb_spinlock = 0; +#define KGDB_SPIN_LOCK(x) --*x +#define KGDB_SPIN_UNLOCK(x) ++*x +#endif + +int +hex(char ch) +{ + if ((ch >= 'a') && (ch <= 'f')) + return (ch - 'a' + 10); + if ((ch >= '0') && (ch <= '9')) + return (ch - '0'); + if ((ch >= 'A') && (ch <= 'F')) + return (ch - 'A' + 10); + return (-1); +} + +/* scan for the sequence $# */ +void +getpacket(char *buffer) +{ + unsigned char checksum; + unsigned char xmitcsum; + int i; + int count; + char ch; + + do { + /* wait around for the start character, ignore all other characters */ + while ((ch = (getDebugChar() & 0x7f)) != '$') ; + checksum = 0; + xmitcsum = -1; + + count = 0; + + /* now, read until a # or end of buffer is found */ + while (count < BUFMAX) { + ch = getDebugChar() & 0x7f; + if (ch == '#') + break; + checksum = checksum + ch; + buffer[count] = ch; + count = count + 1; + } + buffer[count] = 0; + + if (ch == '#') { + xmitcsum = hex(getDebugChar() & 0x7f) << 4; + xmitcsum += hex(getDebugChar() & 0x7f); + if ((remote_debug) && (checksum != xmitcsum)) { + printk + ("bad checksum. My count = 0x%x, sent=0x%x. buf=%s\n", + checksum, xmitcsum, buffer); + } + + if (checksum != xmitcsum) + putDebugChar('-'); /* failed checksum */ + else { + putDebugChar('+'); /* successful transfer */ + /* if a sequence char is present, reply the sequence ID */ + if (buffer[2] == ':') { + putDebugChar(buffer[0]); + putDebugChar(buffer[1]); + /* remove sequence chars from buffer */ + count = strlen(buffer); + for (i = 3; i <= count; i++) + buffer[i - 3] = buffer[i]; + } + } + } + } while (checksum != xmitcsum); + + if (remote_debug) + printk("R:%s\n", buffer); + flushDebugChar(); +} + +/* send the packet in buffer. */ + +void +putpacket(char *buffer) +{ + unsigned char checksum; + int count; + char ch; + + /* $#. */ + + if (!kgdboe) { + do { + if (remote_debug) + printk("T:%s\n", buffer); + putDebugChar('$'); + 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 + */ + +#define MAX_SEND_COUNT 30 + + 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]; +static char remcomOutBuffer[BUFMAX]; +static char lbuf[BUFMAX]; +static short error; + +void +debug_error(char *format, char *parm) +{ + if (remote_debug) + printk(format, parm); +} + +static void +print_regs(struct pt_regs *regs) +{ + printk("RAX=%016lx RBX=%016lx RCX=%016lx\n", + regs->rax, regs->rbx, regs->rcx); + printk("RDX=%016lx RSI=%016lx RDI=%016lx\n", + regs->rdx, regs->rsi, regs->rdi); + printk("RBP=%016lx PS=%016lx PC=%016lx\n", + regs->rbp, regs->eflags, regs->rip); + printk("R8=%016lx R9=%016lx R10=%016lx\n", + regs->r8, regs->r9, regs->r10); + printk("R11=%016lx R12=%016lx R13=%016lx\n", + regs->r11, regs->r12, regs->r13); + printk("R14=%016lx R15=%016lx RSP=%016lx\n", + regs->r14, regs->r15, regs->rsp); +} + +#define NEW_esp fn_call_lookaside[trap_cpu].rsp + +static void +regs_to_gdb_regs(unsigned long *gdb_regs, struct pt_regs *regs) +{ + gdb_regs[_RAX] = regs->rax; + gdb_regs[_RBX] = regs->rbx; + gdb_regs[_RCX] = regs->rcx; + gdb_regs[_RDX] = regs->rdx; + gdb_regs[_RSI] = regs->rsi; + gdb_regs[_RDI] = regs->rdi; + gdb_regs[_RBP] = regs->rbp; + gdb_regs[ _PS] = regs->eflags; + gdb_regs[ _PC] = regs->rip; + gdb_regs[ _R8] = regs->r8; + gdb_regs[ _R9] = regs->r9; + gdb_regs[_R10] = regs->r10; + gdb_regs[_R11] = regs->r11; + gdb_regs[_R12] = regs->r12; + gdb_regs[_R13] = regs->r13; + gdb_regs[_R14] = regs->r14; + gdb_regs[_R15] = regs->r15; + gdb_regs[_RSP] = regs->rsp; + + /* Note, as we are a debugging the kernel, we will always + * trap in kernel code, this means no priviledge change, + * and so the pt_regs structure is not completely valid. In a non + * privilege change trap, only EFLAGS, CS and EIP are put on the stack, + * SS and ESP are not stacked, this means that the last 2 elements of + * pt_regs is not valid (they would normally refer to the user stack) + * also, using regs+1 is no good because you end up will a value that is + * 2 longs (8) too high. This used to cause stepping over functions + * to fail, so my fix is to use the address of regs->esp, which + * should point at the end of the stack frame. Note I have ignored + * completely exceptions that cause an error code to be stacked, such + * as double fault. Stuart Hughes, Zentropix. + * original code: gdb_regs[_ESP] = (int) (regs + 1) ; + + * this is now done on entry and moved to OLD_esp (as well as NEW_esp). + */ +} + +static void +gdb_regs_to_regs(unsigned long *gdb_regs, struct pt_regs *regs) +{ + regs->rax = gdb_regs[_RAX] ; + regs->rbx = gdb_regs[_RBX] ; + regs->rcx = gdb_regs[_RCX] ; + regs->rdx = gdb_regs[_RDX] ; + regs->rsi = gdb_regs[_RSI] ; + regs->rdi = gdb_regs[_RDI] ; + regs->rbp = gdb_regs[_RBP] ; + regs->eflags = gdb_regs[ _PS] ; + regs->rip = gdb_regs[ _PC] ; + regs->r8 = gdb_regs[ _R8] ; + regs->r9 = gdb_regs[ _R9] ; + regs->r10 = gdb_regs[ _R10] ; + regs->r11 = gdb_regs[ _R11] ; + regs->r12 = gdb_regs[ _R12] ; + regs->r13 = gdb_regs[ _R13] ; + regs->r14 = gdb_regs[ _R14] ; + regs->r15 = gdb_regs[ _R15] ; + #if 0 /* can't change these */ + regs->rsp = gdb_regs[_RSP] ; + regs->ss = gdb_regs[ _SS] ; + regs->fs = gdb_regs[_FS]; + regs->gs = gdb_regs[_GS]; +#endif +} /* gdb_regs_to_regs */ + +int thread_list = 0; +extern void thread_return(void); + +void +get_gdb_regs(struct task_struct *p, struct pt_regs *regs, unsigned long *gdb_regs) +{ + unsigned long **rbp, *rsp, *rsp0, pc; + int count = 0; + IF_SMP(int i); + if (!p || p == current) { + regs_to_gdb_regs(gdb_regs, regs); + return; + } +#ifdef CONFIG_SMP + for (i = 0; i < MAX_NO_CPUS; i++) { + if (p == kgdb_info.cpus_waiting[i].task) { + regs_to_gdb_regs(gdb_regs, + kgdb_info.cpus_waiting[i].regs); + gdb_regs[_RSP] = + (unsigned long)&kgdb_info.cpus_waiting[i].regs->rsp; + + return; + } + } +#endif + memset(gdb_regs, 0, NUMREGBYTES); + rsp = (unsigned long *)p->thread.rsp; + rbp = (unsigned long **)rsp[0]; + rsp += 2; + gdb_regs[_PC] = (unsigned long)thread_return; + gdb_regs[_RBP] = (unsigned long)rbp; + gdb_regs[_RSP] = (unsigned long)rsp; + +/* + * This code is to give a more informative notion of where a process + * is waiting. It is used only when the user asks for a thread info + * list. If he then switches to the thread, s/he will find the task + * is in schedule, but a back trace should show the same info we come + * up with. This code was shamelessly purloined from process.c. It was + * then enhanced to provide more registers than simply the program + * counter. + */ + + if (!thread_list) { + return; + } + + if (p->state == TASK_RUNNING) + return; + rsp0 = (unsigned long *)p->thread.rsp0; + if (rsp < (unsigned long *) p->thread_info || rsp > rsp0) + return; + /* include/asm-i386/system.h:switch_to() pushes ebp last. */ + do { + if (*rbp < rsp || *rbp > rsp0) + break; + rbp = (unsigned long **)*rbp; + rsp = (unsigned long *)rbp; + pc = rsp[1]; + + if (!in_sched_functions(pc)) + break; + gdb_regs[_PC] = (unsigned long)pc; + gdb_regs[_RSP] = (unsigned long)rsp; + gdb_regs[_RBP] = (unsigned long)rbp; + } while (count++ < 16); + return; +} + +/* convert the memory pointed to by mem into hex, placing result in buf */ +/* returns nonzero if any memory access fails. */ +int mem2hex( char* mem, char* buf, int count) +{ + int i; + unsigned char ch; + int ret = 0; + + for (i=0;i> 4]; + *buf++ = hexchars[ch % 16]; + } + *buf = 0; + if (ret) { + Dearly_printk("mem2hex: fault at accessing %p\n", mem); + } + return(ret); +} + +/* convert the hex array pointed to by buf into binary to be placed in mem */ +/* return nonzero if any memory access fails. */ +int hex2mem( char* buf, char* mem, int count) +{ + int i; + unsigned char ch; + int ret = 0; + + for (i=0;i (OLD_esp - (unsigned int) LOOKASIDE_SIZE))) { + addr = (char *) END_OF_LOOKASIDE - ((char *) OLD_esp - addr); + } + *addr = val; +} + +/* convert the memory pointed to by mem into hex, placing result in buf */ +/* return a pointer to the last char put in buf (null) */ +/* If MAY_FAULT is non-zero, then we should set mem_err in response to + a fault; if zero treat a fault like any other fault in the stub. */ +char * +mem2hex(char *mem, char *buf, int count, int may_fault) +{ + int i; + unsigned char ch; + + if (may_fault) { + mem_err_expected = 1; + mem_err = 0; + } + for (i = 0; i < count; i++) { + /* printk("%lx = ", mem) ; */ + + ch = get_char(mem++); + + /* printk("%02x\n", ch & 0xFF) ; */ + if (may_fault && mem_err) { + if (remote_debug) + printk("Mem fault fetching from addr %lx\n", + (long) (mem - 1)); + *buf = 0; /* truncate buffer */ + return (buf); + } + *buf++ = hexchars[ch >> 4]; + *buf++ = hexchars[ch % 16]; + } + *buf = 0; + if (may_fault) + mem_err_expected = 0; + return (buf); +} + +/* convert the hex array pointed to by buf into binary to be placed in mem */ +/* return a pointer to the character AFTER the last byte written */ +/* NOTE: We use the may fault flag to also indicate if the write is to + * the registers (0) or "other" memory (!=0) + */ +char * +hex2mem(char *buf, char *mem, int count, int may_fault) +{ + int i; + unsigned char ch; + + if (may_fault) { + mem_err_expected = 1; + mem_err = 0; + } + for (i = 0; i < count; i++) { + ch = hex(*buf++) << 4; + ch = ch + hex(*buf++); + set_char(mem++, ch, may_fault); + + if (may_fault && mem_err) { + if (remote_debug) + printk("Mem fault storing to addr %lx\n", + (long) (mem - 1)); + return (mem); + } + } + if (may_fault) + mem_err_expected = 0; + return (mem); +} +#endif + +/**********************************************/ +/* WHILE WE FIND NICE HEX CHARS, BUILD AN INT */ +/* RETURN NUMBER OF CHARS PROCESSED */ +/**********************************************/ +int +hexToLong(char **ptr, unsigned long *value) +{ + int numChars = 0; + int hexValue; + + *value = 0; + + while (**ptr) { + hexValue = hex(**ptr); + if (hexValue >= 0) { + *value = (*value << 4) | hexValue; + numChars++; + } else + break; + + (*ptr)++; + } + + return (numChars); +} + +#define stubhex(h) hex(h) +#ifdef old_thread_list + +static int +stub_unpack_int(char *buff, int fieldlength) +{ + int nibble; + int retval = 0; + + while (fieldlength) { + nibble = stubhex(*buff++); + retval |= nibble; + fieldlength--; + if (fieldlength) + retval = retval << 4; + } + return retval; +} +#endif +static char * +pack_hex_byte(char *pkt, int byte) +{ + *pkt++ = hexchars[(byte >> 4) & 0xf]; + *pkt++ = hexchars[(byte & 0xf)]; + return pkt; +} + +#define BUF_THREAD_ID_SIZE 16 + +static char * +pack_threadid(char *pkt, threadref * id) +{ + char *limit; + unsigned char *altid; + + altid = (unsigned char *) id; + limit = pkt + BUF_THREAD_ID_SIZE; + while (pkt < limit) + pkt = pack_hex_byte(pkt, *altid++); + return pkt; +} + +#ifdef old_thread_list +static char * +unpack_byte(char *buf, int *value) +{ + *value = stub_unpack_int(buf, 2); + return buf + 2; +} + +static char * +unpack_threadid(char *inbuf, threadref * id) +{ + char *altref; + char *limit = inbuf + BUF_THREAD_ID_SIZE; + int x, y; + + altref = (char *) id; + + while (inbuf < limit) { + x = stubhex(*inbuf++); + y = stubhex(*inbuf++); + *altref++ = (x << 4) | y; + } + return inbuf; +} +#endif +void +int_to_threadref(threadref * id, int value) +{ + unsigned char *scan; + + scan = (unsigned char *) id; + { + int i = 4; + while (i--) + *scan++ = 0; + } + *scan++ = (value >> 24) & 0xff; + *scan++ = (value >> 16) & 0xff; + *scan++ = (value >> 8) & 0xff; + *scan++ = (value & 0xff); +} +int +int_to_hex_v(unsigned char * id, int value) +{ + unsigned char *start = id; + int shift; + int ch; + + for (shift = 28; shift >= 0; shift -= 4) { + if ((ch = (value >> shift) & 0xf) || (id != start)) { + *id = hexchars[ch]; + id++; + } + } + if (id == start) + *id++ = '0'; + return id - start; +} +#ifdef old_thread_list + +static int +threadref_to_int(threadref * ref) +{ + int i, value = 0; + unsigned char *scan; + + scan = (char *) ref; + scan += 4; + i = 4; + while (i-- > 0) + value = (value << 8) | ((*scan++) & 0xff); + return value; +} +#endif +static int +cmp_str(char *s1, char *s2, int count) +{ + while (count--) { + if (*s1++ != *s2++) + return 0; + } + return 1; +} + +#if 1 /* this is a hold over from 2.4 where O(1) was "sometimes" */ +extern struct task_struct *kgdb_get_idle(int cpu); +#define idle_task(cpu) kgdb_get_idle(cpu) +#else +#define idle_task(cpu) init_tasks[cpu] +#endif + +extern int kgdb_pid_init_done; + +struct task_struct * +getthread(int pid) +{ + struct task_struct *thread; + if (pid >= PID_MAX && pid <= (PID_MAX + MAX_NO_CPUS)) { + if (!cpu_online(pid - PID_MAX)) + return NULL; + + return idle_task(pid - PID_MAX); + } else { + /* + * find_task_by_pid is relatively safe all the time + * Other pid functions require lock downs which imply + * that we may be interrupting them (as we get here + * in the middle of most any lock down). + * Still we don't want to call until the table exists! + */ + if (kgdb_pid_init_done){ + thread = find_task_by_pid(pid); + if (thread) { + return thread; + } + } + } + return NULL; +} +/* *INDENT-OFF* */ +struct hw_breakpoint { + unsigned enabled; + unsigned type; + unsigned len; + unsigned long addr; +} breakinfo[4] = { {enabled:0}, + {enabled:0}, + {enabled:0}, + {enabled:0}}; +/* *INDENT-ON* */ +unsigned long hw_breakpoint_status; +void +correct_hw_break(void) +{ + int breakno; + int correctit; + int breakbit; + unsigned long dr7; + + asm volatile ("movq %%db7, %0\n":"=r" (dr7) + :); + /* *INDENT-OFF* */ + do { + unsigned long addr0, addr1, addr2, addr3; + asm volatile ("movq %%db0, %0\n" + "movq %%db1, %1\n" + "movq %%db2, %2\n" + "movq %%db3, %3\n" + :"=r" (addr0), "=r"(addr1), + "=r"(addr2), "=r"(addr3) + :); + } while (0); + /* *INDENT-ON* */ + correctit = 0; + for (breakno = 0; breakno < 3; breakno++) { + breakbit = 2 << (breakno << 1); + if (!(dr7 & breakbit) && breakinfo[breakno].enabled) { + correctit = 1; + dr7 |= breakbit; + dr7 &= ~(0xf0000 << (breakno << 2)); + dr7 |= (((breakinfo[breakno].len << 2) | + breakinfo[breakno].type) << 16) << + (breakno << 2); + switch (breakno) { + case 0: + asm volatile ("movq %0, %%dr0\n"::"r" + (breakinfo[breakno].addr)); + break; + + case 1: + asm volatile ("movq %0, %%dr1\n"::"r" + (breakinfo[breakno].addr)); + break; + + case 2: + asm volatile ("movq %0, %%dr2\n"::"r" + (breakinfo[breakno].addr)); + break; + + case 3: + asm volatile ("movq %0, %%dr3\n"::"r" + (breakinfo[breakno].addr)); + break; + } + } else if ((dr7 & breakbit) && !breakinfo[breakno].enabled) { + correctit = 1; + dr7 &= ~breakbit; + dr7 &= ~(0xf0000 << (breakno << 2)); + } + } + if (correctit) { + asm volatile ("movq %0, %%db7\n"::"r" (dr7)); + } +} + +int +remove_hw_break(unsigned breakno) +{ + if (!breakinfo[breakno].enabled) { + return -1; + } + breakinfo[breakno].enabled = 0; + return 0; +} + +int +set_hw_break(unsigned breakno, unsigned type, unsigned len, unsigned addr) +{ + if (breakinfo[breakno].enabled) { + return -1; + } + breakinfo[breakno].enabled = 1; + breakinfo[breakno].type = type; + breakinfo[breakno].len = len; + breakinfo[breakno].addr = addr; + return 0; +} + +#ifdef CONFIG_SMP +static int in_kgdb_console = 0; + +int +in_kgdb(struct pt_regs *regs) +{ + unsigned long flags; + int cpu; + if (!kgdb_enabled) + return 0; + cpu = smp_processor_id(); + in_kgdb_called = 1; + if (!spin_is_locked(&kgdb_spinlock)) { + if (in_kgdb_here_log[cpu] || /* we are holding this cpu */ + in_kgdb_console) { /* or we are doing slow i/o */ + return 1; + } + return 0; + } + + /* As I see it the only reason not to let all cpus spin on + * the same spin_lock is to allow selected ones to proceed. + * This would be a good thing, so we leave it this way. + * Maybe someday.... Done ! + + * in_kgdb() is called from an NMI so we don't pretend + * to have any resources, like printk() for example. + */ + + local_irq_save(flags); /* only local here, to avoid hanging */ + /* + * log arival of this cpu + * The NMI keeps on ticking. Protect against recurring more + * than once, and ignor the cpu that has the kgdb lock + */ + in_kgdb_entry_log[cpu]++; + in_kgdb_here_log[cpu] = regs; + 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 + * up. We wait here for the wait lock to be taken. If the + * kgdb lock goes away first?? Well, it could be a slow exit + * 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)) + 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 + */ + waiting_cpus[cpu].task = 0; + waiting_cpus[cpu].pid = 0; + waiting_cpus[cpu].regs = 0; + correct_hw_break(); + exit_in_kgdb: + in_kgdb_here_log[cpu] = 0; + local_irq_restore(flags); + return 1; + /* + spin_unlock(continuelocks + smp_processor_id()); + */ +} + +void +smp__in_kgdb(struct pt_regs regs) +{ + ack_APIC_irq(); + in_kgdb(®s); +} +#else +int +in_kgdb(struct pt_regs *regs) +{ + return (kgdb_spinlock); +} +#endif + +void +printexceptioninfo(int exceptionNo, int errorcode, char *buffer) +{ + unsigned long dr6; + int i; + switch (exceptionNo) { + case 1: /* debug exception */ + break; + case 3: /* breakpoint */ + sprintf(buffer, "Software breakpoint"); + return; + default: + sprintf(buffer, "Details not available"); + return; + } + asm volatile ("movq %%db6, %0\n":"=r" (dr6) + :); + if (dr6 & 0x4000) { + sprintf(buffer, "Single step"); + return; + } + for (i = 0; i < 4; ++i) { + if (dr6 & (1 << i)) { + sprintf(buffer, "Hardware breakpoint %d", i); + return; + } + } + sprintf(buffer, "Unknown trap"); + return; +} + +/* + * The ThreadExtraInfo query allows us to pass an arbitrary string + * for display with the "info threads" command. + */ + +void +print_extra_info(task_t *p, char *buf) +{ + if (!p) { + sprintf(buf, "Invalid thread"); + return; + } + sprintf(buf, "0x%p %8d %4d %c %s", + (void *)p, p->parent->pid, + task_cpu(p), + (p->state == 0) ? (task_curr(p)?'R':'r') : + (p->state < 0) ? 'U' : + (p->state & TASK_UNINTERRUPTIBLE) ? 'D' : + (p->state & TASK_STOPPED || p->ptrace & PT_PTRACED) ? 'T' : + (p->state & (EXIT_ZOMBIE | EXIT_DEAD)) ? 'Z' : + (p->state & TASK_INTERRUPTIBLE) ? 'S' : '?', + p->comm); +} + +/* + * This function does all command procesing for interfacing to gdb. + * + * NOTE: The INT nn instruction leaves the state of the interrupt + * enable flag UNCHANGED. That means that when this routine + * is entered via a breakpoint (INT 3) instruction from code + * that has interrupts enabled, then interrupts will STILL BE + * enabled when this routine is entered. The first thing that + * we do here is disable interrupts so as to prevent recursive + * entries and bothersome serial interrupts while we are + * trying to run the serial port in polled mode. + * + * For kernel version 2.1.xx the kgdb_cli() actually gets a spin lock so + * it is always necessary to do a restore_flags before returning + * so as to let go of that lock. + */ +int +kgdb_handle_exception(int exceptionVector, + int signo, int err_code, struct pt_regs *linux_regs) +{ + struct task_struct *usethread = NULL; + struct task_struct *thread_list_start = 0, *thread = NULL; + struct task_struct *p; + unsigned long addr, length; + unsigned long breakno, breaktype; + char *ptr; + unsigned long newPC; + threadref thref; + unsigned long threadid, tmpid; + int thread_min = PID_MAX + MAX_NO_CPUS; +#ifdef old_thread_list + int maxthreads; +#endif + int nothreads; + unsigned long flags; + unsigned long gdb_regs[NUMREGS]; + unsigned long dr6; + IF_SMP(int entry_state = 0); /* 0, ok, 1, no nmi, 2 sync failed */ +#define NO_NMI 1 +#define NO_SYNC 2 +#define regs (*linux_regs) + /* + * If the entry is not from the kernel then return to the Linux + * trap handler and let it process the interrupt normally. + */ + if ((linux_regs->eflags & VM_MASK) || (3 & linux_regs->cs)) { + printk("ignoring non-kernel exception\n"); + print_regs(®s); + return (0); + } + /* + * If we're using eth mode, set the 'mode' in the netdevice. + */ + + if (kgdboe) + netpoll_set_trap(1); + + local_irq_save(flags); + + /* Get kgdb spinlock */ + + KGDB_SPIN_LOCK(&kgdb_spinlock); + rdtscll(kgdb_info.entry_tsc); + /* + * We depend on this spinlock and the NMI watch dog to control the + * other cpus. They will arrive at "in_kgdb()" as a result of the + * NMI and will wait there for the following spin locks to be + * released. + */ +#ifdef CONFIG_SMP + +#if 0 + if (cpu_callout_map & ~MAX_CPU_MASK) { + printk("kgdb : too many cpus, possibly not mapped" + " in contiguous space, change MAX_NO_CPUS" + " in kgdb_stub and make new kernel.\n" + " cpu_callout_map is %lx\n", cpu_callout_map); + goto exit_just_unlock; + } +#endif + if (spinlock_count == 1) { + int time, end_time, dum; + int i; + int cpu_logged_in[MAX_NO_CPUS] = {[0 ... MAX_NO_CPUS - 1] = (0) + }; + if (remote_debug) { + printk("kgdb : cpu %d entry, syncing others\n", + smp_processor_id()); + } + for (i = 0; i < MAX_NO_CPUS; i++) { + /* + * Use trylock as we may already hold the lock if + * we are holding the cpu. Net result is all + * locked. + */ + spin_trylock(&waitlocks[i]); + } + for (i = 0; i < MAX_NO_CPUS; i++) + cpu_logged_in[i] = 0; + /* + * Wait for their arrival. We know the watch dog is active if + * in_kgdb() has ever been called, as it is always called on a + * watchdog tick. + */ + rdtsc(dum, time); + end_time = time + 2; /* Note: we use the High order bits! */ + i = 1; + 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; + if (remote_debug) { + printk + ("kgdb : cpu %d arrived at kgdb\n", + j); + } + break; + } else if (!waiting_cpus[j].task && + !cpu_online(j)) { + waiting_cpus[j].task = NOCPU; + cpu_logged_in[j] = 1; + waiting_cpus[j].hold = 1; + break; + } + if (!waiting_cpus[j].task && + in_kgdb_here_log[j]) { + + int wait = 100000; + while (wait--) ; + if (!waiting_cpus[j].task && + in_kgdb_here_log[j]) { + printk + ("kgdb : cpu %d stall" + " in in_kgdb\n", + j); + i++; + cpu_logged_in[j] = 1; + waiting_cpus[j].task = + (struct task_struct + *) 1; + } + } + } + + if (in_kgdb_entry_log[smp_processor_id()] > + (me_in_kgdb + 10)) { + break; + } + + rdtsc(dum, time); + } + if (i < num_online_cpus()) { + printk + ("kgdb : time out, proceeding without sync\n"); +#if 0 + printk("kgdb : Waiting_cpus: 0 = %d, 1 = %d\n", + waiting_cpus[0].task != 0, + waiting_cpus[1].task != 0); + printk("kgdb : Cpu_logged in: 0 = %d, 1 = %d\n", + cpu_logged_in[0], cpu_logged_in[1]); + printk + ("kgdb : in_kgdb_here_log in: 0 = %d, 1 = %d\n", + in_kgdb_here_log[0] != 0, + in_kgdb_here_log[1] != 0); +#endif + entry_state = NO_SYNC; + } else { +#if 0 + int ent = + in_kgdb_entry_log[smp_processor_id()] - + me_in_kgdb; + printk("kgdb : sync after %d entries\n", ent); +#endif + } + } else { + if (remote_debug) { + printk + ("kgdb : %d cpus, but watchdog not active\n" + "proceeding without locking down other cpus\n", + (int)num_online_cpus()); + entry_state = NO_NMI; + } + } + } +#endif + + if (remote_debug) { + unsigned long *lp = (unsigned long *) &linux_regs; + + printk("handle_exception(exceptionVector=%d, " + "signo=%d, err_code=%d, linux_regs=%p)\n", + exceptionVector, signo, err_code, linux_regs); + if (debug_regs) { + print_regs(®s); + printk("Stk: %8lx %8lx %8lx %8lx" + " %8lx %8lx %8lx %8lx\n", + lp[0], lp[1], lp[2], lp[3], + lp[4], lp[5], lp[6], lp[7]); + printk(" %8lx %8lx %8lx %8lx" + " %8lx %8lx %8lx %8lx\n", + lp[8], lp[9], lp[10], lp[11], + lp[12], lp[13], lp[14], lp[15]); + printk(" %8lx %8lx %8lx %8lx " + "%8lx %8lx %8lx %8lx\n", + lp[16], lp[17], lp[18], lp[19], + lp[20], lp[21], lp[22], lp[23]); + printk(" %8lx %8lx %8lx %8lx " + "%8lx %8lx %8lx %8lx\n", + lp[24], lp[25], lp[26], lp[27], + lp[28], lp[29], lp[30], lp[31]); + } + } + + /* Disable hardware debugging while we are in kgdb */ + /* Get the debug register status register */ +/* *INDENT-OFF* */ + __asm__("movq %0,%%db7" + : /* no output */ + :"r"(0UL)); + + asm volatile ("movq %%db6, %0\n" + :"=r" (hw_breakpoint_status) + :); + +#if 0 +/* *INDENT-ON* */ + switch (exceptionVector) { + case 0: /* divide error */ + case 1: /* debug exception */ + case 2: /* NMI */ + case 3: /* breakpoint */ + case 4: /* overflow */ + case 5: /* bounds check */ + case 6: /* invalid opcode */ + case 7: /* device not available */ + case 8: /* double fault (errcode) */ + case 10: /* invalid TSS (errcode) */ + case 12: /* stack fault (errcode) */ + case 16: /* floating point error */ + case 17: /* alignment check (errcode) */ + default: /* any undocumented */ + break; + case 11: /* segment not present (errcode) */ + case 13: /* general protection (errcode) */ + case 14: /* page fault (special errcode) */ + case 19: /* cache flush denied */ + if (mem_err_expected) { + /* + * This fault occured because of the + * get_char or set_char routines. These + * two routines use either eax of edx to + * indirectly reference the location in + * memory that they are working with. + * For a page fault, when we return the + * instruction will be retried, so we + * have to make sure that these + * registers point to valid memory. + */ + mem_err = 1; /* set mem error flag */ + mem_err_expected = 0; + mem_err_cnt++; /* helps in debugging */ + /* make valid address */ + regs.eax = (long) &garbage_loc; + /* make valid address */ + regs.edx = (long) &garbage_loc; + if (remote_debug) + printk("Return after memory error: " + "mem_err_cnt=%d\n", mem_err_cnt); + if (debug_regs) + print_regs(®s); + goto exit_kgdb; + } + break; + } +#endif + if (remote_debug) + printk("kgdb : entered kgdb on cpu %d\n", smp_processor_id()); + + gdb_i386vector = exceptionVector; + gdb_i386errcode = err_code; + kgdb_info.called_from = __builtin_return_address(0); +#ifdef CONFIG_SMP + /* + * OK, we can now communicate, lets tell gdb about the sync. + * but only if we had a problem. + */ + switch (entry_state) { + case NO_NMI: + to_gdb("NMI not active, other cpus not stopped\n"); + break; + case NO_SYNC: + to_gdb("Some cpus not stopped, see 'kgdb_info' for details\n"); + default:; + } + +#endif +/* + * Set up the gdb function call area. + */ + trap_cpu = smp_processor_id(); + OLD_esp = NEW_esp = (unsigned long) (&linux_regs->rsp); + + IF_SMP(once_again:) + /* reply to host that an exception has occurred */ + remcomOutBuffer[0] = 'S'; + remcomOutBuffer[1] = hexchars[signo >> 4]; + remcomOutBuffer[2] = hexchars[signo % 16]; + remcomOutBuffer[3] = 0; + + putpacket(remcomOutBuffer); + + while (1 == 1) { + error = 0; + remcomOutBuffer[0] = 0; + getpacket(remcomInBuffer); + switch (remcomInBuffer[0]) { + case '?': + remcomOutBuffer[0] = 'S'; + remcomOutBuffer[1] = hexchars[signo >> 4]; + remcomOutBuffer[2] = hexchars[signo % 16]; + remcomOutBuffer[3] = 0; + break; + case 'd': + remote_debug = !(remote_debug); /* toggle debug flag */ + printk("Remote debug %s\n", + remote_debug ? "on" : "off"); + break; + case 'g': /* return the value of the CPU registers */ + get_gdb_regs(usethread, ®s, gdb_regs); + mem2hex((char *) gdb_regs, + remcomOutBuffer, NUMREGBYTES); + break; + case 'G': /* set the value of the CPU registers - return OK */ + hex2mem(&remcomInBuffer[1], + (char *) gdb_regs, NUMREGBYTES); + if (!usethread || usethread == current) { + gdb_regs_to_regs(gdb_regs, ®s); + strcpy(remcomOutBuffer, "OK"); + } else { + strcpy(remcomOutBuffer, "E00"); + } + break; + + case 'P':{ /* set the value of a single CPU register - + return OK */ + /* + * For some reason, gdb wants to talk about psudo + * registers (greater than 15). + */ + unsigned long regno; + + ptr = &remcomInBuffer[1]; + regs_to_gdb_regs(gdb_regs, ®s); + if ((!usethread || usethread == current) && + hexToLong(&ptr, ®no) && + *ptr++ == '=' && (regno >= 0)) { + if (regno >= NUMREGS) + break; + hex2mem(ptr, (char *) &gdb_regs[regno], + 8); + gdb_regs_to_regs(gdb_regs, ®s); + strcpy(remcomOutBuffer, "OK"); + break; + } + strcpy(remcomOutBuffer, "E01"); + break; + } + + /* mAA..AA,LLLL Read LLLL bytes at address AA..AA */ + case 'm': + /* TRY TO READ %x,%x. IF SUCCEED, SET PTR = 0 */ + ptr = &remcomInBuffer[1]; + if (hexToLong(&ptr, &addr) && + (*(ptr++) == ',') && (hexToLong(&ptr, &length))) { + ptr = 0; + /* + * hex doubles the byte count + */ + if (length > (BUFMAX / 2)) + length = BUFMAX / 2; + if (mem2hex((char *) addr, + remcomOutBuffer, length)) { + strcpy(remcomOutBuffer, "E03"); + debug_error("memory fault\n", NULL); + } + } + + if (ptr) { + strcpy(remcomOutBuffer, "E01"); + debug_error + ("malformed read memory command: %s\n", + remcomInBuffer); + } + break; + + /* MAA..AA,LLLL: + Write LLLL bytes at address AA.AA return OK */ + case 'M': + /* TRY TO READ '%x,%x:'. IF SUCCEED, SET PTR = 0 */ + ptr = &remcomInBuffer[1]; + if (hexToLong(&ptr, &addr) && + (*(ptr++) == ',') && + (hexToLong(&ptr, &length)) && (*(ptr++) == ':')) { + if (hex2mem(ptr, (char *) addr, length)) { + strcpy(remcomOutBuffer, "E03"); + debug_error("memory fault\n", NULL); + } else { + strcpy(remcomOutBuffer, "OK"); + } + + ptr = 0; + } + if (ptr) { + strcpy(remcomOutBuffer, "E02"); + debug_error + ("malformed write memory command: %s\n", + remcomInBuffer); + } + break; + case 'S': + remcomInBuffer[0] = 's'; + case 'C': + /* Csig;AA..AA where ;AA..AA is optional + * continue with signal + * Since signals are meaning less to us, delete that + * part and then fall into the 'c' code. + */ + ptr = &remcomInBuffer[1]; + length = 2; + while (*ptr && *ptr != ';') { + length++; + ptr++; + } + if (*ptr) { + do { + ptr++; + *(ptr - length++) = *ptr; + } while (*ptr); + } else { + remcomInBuffer[1] = 0; + } + + /* cAA..AA Continue at address AA..AA(optional) */ + /* sAA..AA Step one instruction from AA..AA(optional) */ + /* D detach, reply OK and then continue */ + case 'c': + case 's': + case 'D': + + /* try to read optional parameter, + pc unchanged if no parm */ + ptr = &remcomInBuffer[1]; + if (hexToLong(&ptr, &addr)) { + if (remote_debug) + printk("Changing EIP to 0x%lx\n", addr); + + regs.rip = addr; + } + + newPC = regs.rip; + + /* clear the trace bit */ + regs.eflags &= 0xfffffeff; + + /* set the trace bit if we're stepping */ + if (remcomInBuffer[0] == 's') + regs.eflags |= 0x100; + + /* detach is a friendly version of continue. Note that + debugging is still enabled (e.g hit control C) + */ + if (remcomInBuffer[0] == 'D') { + strcpy(remcomOutBuffer, "OK"); + putpacket(remcomOutBuffer); + } + + if (remote_debug) { + printk("Resuming execution\n"); + print_regs(®s); + } + asm volatile ("movq %%db6, %0\n":"=r" (dr6) + :); + if (!(dr6 & 0x4000)) { + for (breakno = 0; breakno < 4; ++breakno) { + if (dr6 & (1 << breakno) && + (breakinfo[breakno].type == 0)) { + /* Set restore flag */ + regs.eflags |= 0x10000; + break; + } + } + } + + if (kgdboe) + netpoll_set_trap(0); + + correct_hw_break(); + asm volatile ("movq %0, %%db6\n"::"r" (0UL)); + goto exit_kgdb; + + /* kill the program */ + case 'k': /* do nothing */ + break; + + /* query */ + case 'q': + nothreads = 0; + switch (remcomInBuffer[1]) { + case 'f': + threadid = 1; + thread_list = 2; + thread_list_start = (usethread ? : current); + case 's': + if (!cmp_str(&remcomInBuffer[2], + "ThreadInfo", 10)) + break; + + remcomOutBuffer[nothreads++] = 'm'; + for (; threadid < PID_MAX + MAX_NO_CPUS; + threadid++) { + thread = getthread(threadid); + if (thread) { + nothreads += int_to_hex_v( + &remcomOutBuffer[ + nothreads], + threadid); + if (thread_min > threadid) + thread_min = threadid; + remcomOutBuffer[ + nothreads] = ','; + nothreads++; + if (nothreads > BUFMAX - 10) + break; + } + } + if (remcomOutBuffer[nothreads - 1] == 'm') { + remcomOutBuffer[nothreads - 1] = 'l'; + } else { + nothreads--; + } + remcomOutBuffer[nothreads] = 0; + break; + +#ifdef old_thread_list /* Old thread info request */ + case 'L': + /* List threads */ + thread_list = 2; + thread_list_start = (usethread ? : current); + unpack_byte(remcomInBuffer + 3, &maxthreads); + unpack_threadid(remcomInBuffer + 5, &thref); + do { + int buf_thread_limit = + (BUFMAX - 22) / BUF_THREAD_ID_SIZE; + if (maxthreads > buf_thread_limit) { + maxthreads = buf_thread_limit; + } + } while (0); + remcomOutBuffer[0] = 'q'; + remcomOutBuffer[1] = 'M'; + remcomOutBuffer[4] = '0'; + pack_threadid(remcomOutBuffer + 5, &thref); + + /* If start flag set start at 0. */ + if (remcomInBuffer[2] == '1') + threadid = 0; + else + threadid = threadref_to_int(&thref); + for (nothreads = 0; + nothreads < maxthreads && + threadid < PID_MAX + MAX_NO_CPUS; + threadid++) { + thread = getthread(threadid); + if (thread) { + int_to_threadref(&thref, + threadid); + pack_threadid(remcomOutBuffer + + 21 + + nothreads * 16, + &thref); + nothreads++; + if (thread_min > threadid) + thread_min = threadid; + } + } + + if (threadid == PID_MAX + MAX_NO_CPUS) { + remcomOutBuffer[4] = '1'; + } + pack_hex_byte(remcomOutBuffer + 2, nothreads); + remcomOutBuffer[21 + nothreads * 16] = '\0'; + break; +#endif + case 'C': + /* Current thread id */ + remcomOutBuffer[0] = 'Q'; + remcomOutBuffer[1] = 'C'; + threadid = current->pid; + if (!threadid) { + /* + * idle thread + */ + for (threadid = PID_MAX; + threadid < PID_MAX + MAX_NO_CPUS; + threadid++) { + if (current == + idle_task(threadid - + PID_MAX)) + break; + } + } + int_to_threadref(&thref, threadid); + pack_threadid(remcomOutBuffer + 2, &thref); + remcomOutBuffer[18] = '\0'; + break; + + case 'E': + /* Print exception info */ + printexceptioninfo(exceptionVector, + err_code, remcomOutBuffer); + break; + case 'T': + ptr = &remcomInBuffer[0]; + if (strncmp(ptr, "qThreadExtraInfo,", + strlen("qThreadExtraInfo,")) == 0) { + ptr += strlen("qThreadExtraInfo,"); + hexToLong(&ptr, &tmpid); + p = getthread(tmpid); + print_extra_info(p, lbuf); + mem2hex(lbuf, remcomOutBuffer, + strlen(lbuf)); + } + break; +#if 0 + case 'T':{ + char * nptr; + /* Thread extra info */ + if (!cmp_str(&remcomInBuffer[2], + "hreadExtraInfo,", 15)) { + break; + } + ptr = &remcomInBuffer[17]; + hexToLong(&ptr, &threadid); + thread = getthread(threadid); + nptr = &thread->comm[0]; + length = 0; + ptr = &remcomOutBuffer[0]; + do { + length++; + ptr = pack_hex_byte(ptr, *nptr++); + } while (*nptr && length < 16); + /* + * would like that 16 to be the size of + * task_struct.comm but don't know the + * syntax.. + */ + *ptr = 0; + } +#endif + } + break; + + /* task related */ + case 'H': + switch (remcomInBuffer[1]) { + case 'g': + ptr = &remcomInBuffer[2]; + hexToLong(&ptr, &threadid); + thread = getthread(threadid); + if (!thread) { + remcomOutBuffer[0] = 'E'; + remcomOutBuffer[1] = '\0'; + break; + } + /* + * Just in case I forget what this is all about, + * the "thread info" command to gdb causes it + * to ask for a thread list. It then switches + * to each thread and asks for the registers. + * For this (and only this) usage, we want to + * fudge the registers of tasks not on the run + * list (i.e. waiting) to show the routine that + * called schedule. Also, gdb, is a minimalist + * in that if the current thread is the last + * it will not re-read the info when done. + * This means that in this case we must show + * the real registers. So here is how we do it: + * Each entry we keep track of the min + * thread in the list (the last that gdb will) + * get info for. We also keep track of the + * starting thread. + * "thread_list" is cleared when switching back + * to the min thread if it is was current, or + * if it was not current, thread_list is set + * to 1. When the switch to current comes, + * if thread_list is 1, clear it, else do + * nothing. + */ + usethread = thread; + if ((thread_list == 1) && + (thread == thread_list_start)) { + thread_list = 0; + } + if (thread_list && (threadid == thread_min)) { + if (thread == thread_list_start) { + thread_list = 0; + } else { + thread_list = 1; + } + } + /* follow through */ + case 'c': + remcomOutBuffer[0] = 'O'; + remcomOutBuffer[1] = 'K'; + remcomOutBuffer[2] = '\0'; + break; + } + break; + + /* Query thread status */ + case 'T': + ptr = &remcomInBuffer[1]; + hexToLong(&ptr, &threadid); + thread = getthread(threadid); + if (thread) { + remcomOutBuffer[0] = 'O'; + remcomOutBuffer[1] = 'K'; + remcomOutBuffer[2] = '\0'; + if (thread_min > threadid) + thread_min = threadid; + } else { + remcomOutBuffer[0] = 'E'; + remcomOutBuffer[1] = '\0'; + } + break; + + case 'Y': /* set up a hardware breakpoint */ + ptr = &remcomInBuffer[1]; + hexToLong(&ptr, &breakno); + ptr++; + hexToLong(&ptr, &breaktype); + ptr++; + hexToLong(&ptr, &length); + ptr++; + hexToLong(&ptr, &addr); + if (set_hw_break(breakno & 0x3, + breaktype & 0x3, + length & 0x3, addr) == 0) { + strcpy(remcomOutBuffer, "OK"); + } else { + strcpy(remcomOutBuffer, "ERROR"); + } + break; + + /* Remove hardware breakpoint */ + case 'y': + ptr = &remcomInBuffer[1]; + hexToLong(&ptr, &breakno); + if (remove_hw_break(breakno & 0x3) == 0) { + strcpy(remcomOutBuffer, "OK"); + } else { + strcpy(remcomOutBuffer, "ERROR"); + } + break; + + case 'r': /* reboot */ + strcpy(remcomOutBuffer, "OK"); + putpacket(remcomOutBuffer); + /*to_gdb("Rebooting\n"); */ + /* triplefault no return from here */ + { + static long no_idt[2]; + __asm__ __volatile__("lidt %0"::"m"(no_idt[0])); + BREAKPOINT; + } + + } /* switch */ + + /* reply to the request */ + putpacket(remcomOutBuffer); + } /* while(1==1) */ + /* + * reached by goto only. + */ + exit_kgdb: + /* + * Here is where we set up to trap a gdb function call. NEW_esp + * will be changed if we are trying to do this. We handle both + * adding and subtracting, thus allowing gdb to put grung on + * the stack which it removes later. + */ + if (NEW_esp != OLD_esp) { + unsigned long *ptr = END_OF_LOOKASIDE; + if (NEW_esp < OLD_esp) + ptr -= (OLD_esp - NEW_esp) / sizeof (unsigned long); + *--ptr = linux_regs->eflags; + *--ptr = linux_regs->cs; + *--ptr = linux_regs->rip; + *--ptr = linux_regs->rcx; + *--ptr = linux_regs->rbx; + *--ptr = linux_regs->rax; + linux_regs->rcx = NEW_esp - (sizeof (unsigned long) * 6); + linux_regs->rbx = (unsigned long) END_OF_LOOKASIDE; + if (NEW_esp < OLD_esp) { + linux_regs->rip = (unsigned long) fn_call_stub; + } else { + linux_regs->rip = (unsigned long) fn_rtn_stub; + linux_regs->rax = NEW_esp; + } + linux_regs->eflags &= ~(IF_BIT | TF_BIT); + } +#ifdef CONFIG_SMP + /* + * Release gdb wait locks + * Sanity check time. Must have at least one cpu to run. Also single + * step must not be done if the current cpu is on hold. + */ + if (spinlock_count == 1) { + int ss_hold = (regs.eflags & 0x100) && kgdb_info.hold_on_sstep; + int cpu_avail = 0; + int i; + + for (i = 0; i < MAX_NO_CPUS; i++) { + if (!cpu_online(i)) + break; + if (!hold_cpu(i)) { + cpu_avail = 1; + } + } + /* + * Early in the bring up there will be NO cpus on line... + */ + if (!cpu_avail && !cpus_empty(cpu_online_map)) { + to_gdb("No cpus unblocked, see 'kgdb_info.hold_cpu'\n"); + goto once_again; + } + if (hold_cpu(smp_processor_id()) && (regs.eflags & 0x100)) { + to_gdb + ("Current cpu must be unblocked to single step\n"); + goto once_again; + } + if (!(ss_hold)) { + int i; + for (i = 0; i < MAX_NO_CPUS; i++) { + if (!hold_cpu(i)) { + spin_unlock(&waitlocks[i]); + } + } + } else { + spin_unlock(&waitlocks[smp_processor_id()]); + } + /* Release kgdb spinlock */ + KGDB_SPIN_UNLOCK(&kgdb_spinlock); + /* + * If this cpu is on hold, this is where we + * do it. Note, the NMI will pull us out of here, + * but will return as the above lock is not held. + * We will stay here till another cpu releases the lock for us. + */ + spin_unlock_wait(waitlocks + smp_processor_id()); + local_irq_restore(flags); + return (1); + } +#if 0 +exit_just_unlock: +#endif +#endif + /* Release kgdb spinlock */ + KGDB_SPIN_UNLOCK(&kgdb_spinlock); + local_irq_restore(flags); + return (1); +} + +#undef regs +static int kgdb_notify(struct notifier_block *self, unsigned long cmd, void *ptr) +{ + struct die_args *d = ptr; + + if (cmd == DIE_PAGE_FAULT) + return NOTIFY_DONE; + if (!kgdb_enabled || (cmd == DIE_DEBUG && user_mode(d->regs))) + return NOTIFY_DONE; + if (cmd == DIE_NMI_IPI) { + if (in_kgdb(d->regs)) + return NOTIFY_STOP; + } else if (kgdb_handle_exception(d->trapnr, d->signr, d->err, d->regs)) + return NOTIFY_STOP; /* skip */ + + return NOTIFY_DONE; +} + +static struct notifier_block kgdb_notifier = { + .notifier_call = kgdb_notify, + .priority = 0, +}; + +void set_debug_traps(void) +{ + static int initialized = 0; + + if (!initialized) { + initialized = 1; + notifier_chain_register(&die_chain, &kgdb_notifier); + } +} + +/* + * Provide the command line "gdb" initial break + */ +int __init kgdb_initial_break(char * str) +{ + if (*str == '\0'){ + breakpoint(); + return 1; + } + return 0; +} +__setup("gdb",kgdb_initial_break); + +/* This function will generate a breakpoint exception. It is used at the + beginning of a program to sync up with a debugger and can be used + otherwise as a quick means to stop program execution and "break" into + the debugger. */ +/* But really, just use the BREAKPOINT macro. We will handle the int stuff + */ + +void breakpoint(void) +{ + + set_debug_traps(); + kgdb_enabled = 1; +#if 0 + /* + * These calls were not enough to allow breakpoint to be + * called before trap_init(). I moved the argument parsing + * after trap_init() and it seems to work. + */ + set_intr_usr_gate(3,&int3); /* disable ints on trap */ + set_intr_gate(1,&debug); + set_intr_gate(14,&page_fault); +#endif + + BREAKPOINT; +} + +#ifdef later +/* + * possibly we should not go thru the traps.c code at all? Someday. + */ +void +do_kgdb_int3(struct pt_regs *regs, long error_code) +{ + kgdb_handle_exception(3, 5, error_code, regs); + return; +} +#endif +#undef regs +#ifdef CONFIG_TRAP_BAD_SYSCALL_EXITS +asmlinkage void +bad_sys_call_exit(int stuff) +{ + struct pt_regs *regs = (struct pt_regs *) &stuff; + printk("Sys call %d return with %x preempt_count\n", + (int) regs->orig_eax, preempt_count()); +} +#endif +#ifdef CONFIG_STACK_OVERFLOW_TEST +#include +asmlinkage void +stack_overflow(void) +{ +#ifdef BREAKPOINT + BREAKPOINT; +#else + printk("Kernel stack overflow, looping forever\n"); +#endif + while (1) { + } +} +#endif + +#if defined(CONFIG_SMP) || defined(CONFIG_KGDB_CONSOLE) +char gdbconbuf[BUFMAX]; + +static void +kgdb_gdb_message(const char *s, unsigned count) +{ + int i; + int wcount; + char *bufptr; + /* + * This takes care of NMI while spining out chars to gdb + */ + IF_SMP(in_kgdb_console = 1); + gdbconbuf[0] = 'O'; + bufptr = gdbconbuf + 1; + while (count > 0) { + if ((count << 1) > (BUFMAX - 2)) { + wcount = (BUFMAX - 2) >> 1; + } else { + wcount = count; + } + count -= wcount; + for (i = 0; i < wcount; i++) { + bufptr = pack_hex_byte(bufptr, s[i]); + } + *bufptr = '\0'; + s += wcount; + + putpacket(gdbconbuf); + + } + IF_SMP(in_kgdb_console = 0); +} +#endif +#ifdef CONFIG_SMP +static void +to_gdb(const char *s) +{ + int count = 0; + while (s[count] && (count++ < BUFMAX)) ; + kgdb_gdb_message(s, count); +} +#endif +#ifdef CONFIG_KGDB_CONSOLE +#include +#include +#include +#include + +void +kgdb_console_write(struct console *co, const char *s, unsigned count) +{ + + if (gdb_i386vector == -1) { + /* + * We have not yet talked to gdb. What to do... + * lets break, on continue we can do the write. + * But first tell him whats up. Uh, well no can do, + * as this IS the console. Oh well... + * We do need to wait or the messages will be lost. + * Other option would be to tell the above code to + * ignore this breakpoint and do an auto return, + * but that might confuse gdb. Also this happens + * early enough in boot up that we don't have the traps + * set up yet, so... + */ + breakpoint(); + } + kgdb_gdb_message(s, count); +} + +/* + * ------------------------------------------------------------ + * Serial KGDB driver + * ------------------------------------------------------------ + */ + +static struct console kgdbcons = { + name:"kgdb", + write:kgdb_console_write, +#ifdef CONFIG_KGDB_USER_CONSOLE + device:kgdb_console_device, +#endif + flags:CON_PRINTBUFFER | CON_ENABLED, + index:-1, +}; + +/* + * The trick here is that this file gets linked before printk.o + * That means we get to peer at the console info in the command + * line before it does. If we are up, we register, otherwise, + * do nothing. By returning 0, we allow printk to look also. + */ +static int kgdb_console_enabled; + +int __init +kgdb_console_init(char *str) +{ + if ((strncmp(str, "kgdb", 4) == 0) || (strncmp(str, "gdb", 3) == 0)) { + register_console(&kgdbcons); + kgdb_console_enabled = 1; + } + return 0; /* let others look at the string */ +} + +__setup("console=", kgdb_console_init); + +#ifdef CONFIG_KGDB_USER_CONSOLE +static kdev_t kgdb_console_device(struct console *c); +/* This stuff sort of works, but it knocks out telnet devices + * we are leaving it here in case we (or you) find time to figure it out + * better.. + */ + +/* + * We need a real char device as well for when the console is opened for user + * space activities. + */ + +static int +kgdb_consdev_open(struct inode *inode, struct file *file) +{ + return 0; +} + +static ssize_t +kgdb_consdev_write(struct file *file, const char *buf, + size_t count, loff_t * ppos) +{ + int size, ret = 0; + static char kbuf[128]; + static DECLARE_MUTEX(sem); + + /* We are not reentrant... */ + if (down_interruptible(&sem)) + return -ERESTARTSYS; + + while (count > 0) { + /* need to copy the data from user space */ + size = count; + if (size > sizeof (kbuf)) + size = sizeof (kbuf); + if (copy_from_user(kbuf, buf, size)) { + ret = -EFAULT; + break;; + } + kgdb_console_write(&kgdbcons, kbuf, size); + count -= size; + ret += size; + buf += size; + } + + up(&sem); + + return ret; +} + +struct file_operations kgdb_consdev_fops = { + open:kgdb_consdev_open, + write:kgdb_consdev_write +}; +static kdev_t +kgdb_console_device(struct console *c) +{ + return MKDEV(TTYAUX_MAJOR, 1); +} + +/* + * This routine gets called from the serial stub in the i386/lib + * This is so it is done late in bring up (just before the console open). + */ +void +kgdb_console_finit(void) +{ + if (kgdb_console_enabled) { + char *cptr = cdevname(MKDEV(TTYAUX_MAJOR, 1)); + char *cp = cptr; + while (*cptr && *cptr != '(') + cptr++; + *cptr = 0; + unregister_chrdev(TTYAUX_MAJOR, cp); + register_chrdev(TTYAUX_MAJOR, "kgdb", &kgdb_consdev_fops); + } +} +#endif +#endif +#ifdef CONFIG_KGDB_TS +#include /* time stamp code */ +#include /* in_interrupt */ +#ifdef CONFIG_KGDB_TS_64 +#define DATA_POINTS 64 +#endif +#ifdef CONFIG_KGDB_TS_128 +#define DATA_POINTS 128 +#endif +#ifdef CONFIG_KGDB_TS_256 +#define DATA_POINTS 256 +#endif +#ifdef CONFIG_KGDB_TS_512 +#define DATA_POINTS 512 +#endif +#ifdef CONFIG_KGDB_TS_1024 +#define DATA_POINTS 1024 +#endif +#ifndef DATA_POINTS +#define DATA_POINTS 128 /* must be a power of two */ +#endif +#define INDEX_MASK (DATA_POINTS - 1) +#if (INDEX_MASK & DATA_POINTS) +#error "CONFIG_KGDB_TS_COUNT must be a power of 2" +#endif +struct kgdb_and_then_struct { +#ifdef CONFIG_SMP + int on_cpu; +#endif + struct task_struct *task; + long long at_time; + int from_ln; + char *in_src; + void *from; + int *with_shpf; + int data0; + int data1; +}; +struct kgdb_and_then_struct2 { +#ifdef CONFIG_SMP + int on_cpu; +#endif + struct task_struct *task; + long long at_time; + int from_ln; + char *in_src; + void *from; + int *with_shpf; + struct task_struct *t1; + struct task_struct *t2; +}; +struct kgdb_and_then_struct kgdb_data[DATA_POINTS]; + +struct kgdb_and_then_struct *kgdb_and_then = &kgdb_data[0]; +int kgdb_and_then_count; + +void +kgdb_tstamp(int line, char *source, int data0, int data1) +{ + static spinlock_t ts_spin = SPIN_LOCK_UNLOCKED; + unsigned long flags; + + local_irq_save(flags); + spin_lock(&ts_spin); + rdtscll(kgdb_and_then->at_time); +#ifdef CONFIG_SMP + kgdb_and_then->on_cpu = smp_processor_id(); +#endif + kgdb_and_then->task = current; + kgdb_and_then->from_ln = line; + kgdb_and_then->in_src = source; + kgdb_and_then->from = __builtin_return_address(0); + kgdb_and_then->with_shpf = (int *)(long)(((flags & IF_BIT) >> 9) | + (preempt_count() << 8)); + kgdb_and_then->data0 = data0; + kgdb_and_then->data1 = data1; + kgdb_and_then = &kgdb_data[++kgdb_and_then_count & INDEX_MASK]; + spin_unlock(&ts_spin); + local_irq_restore(flags); +#ifdef CONFIG_PREEMPT + +#endif + return; +} +#endif +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; + kgdb_enabled = 1; + BREAKPOINT; + } +} + diff -puN arch/x86_64/kernel/Makefile~kgdb-x86_64-support arch/x86_64/kernel/Makefile --- devel/arch/x86_64/kernel/Makefile~kgdb-x86_64-support 2005-07-26 00:38:32.000000000 -0700 +++ devel-akpm/arch/x86_64/kernel/Makefile 2005-07-26 00:38:32.000000000 -0700 @@ -32,6 +32,7 @@ obj-$(CONFIG_KPROBES) += kprobes.o obj-$(CONFIG_X86_PM_TIMER) += pmtimer.o obj-$(CONFIG_MODULES) += module.o +obj-$(CONFIG_KGDB) += kgdb_stub.o obj-y += topology.o obj-y += intel_cacheinfo.o diff -puN arch/x86_64/kernel/smp.c~kgdb-x86_64-support arch/x86_64/kernel/smp.c --- devel/arch/x86_64/kernel/smp.c~kgdb-x86_64-support 2005-07-26 00:38:32.000000000 -0700 +++ devel-akpm/arch/x86_64/kernel/smp.c 2005-07-26 00:38:32.000000000 -0700 @@ -267,6 +267,18 @@ void smp_send_reschedule(int cpu) send_IPI_mask(cpumask_of_cpu(cpu), RESCHEDULE_VECTOR); } +#ifdef CONFIG_KGDB +/* + * By using the NMI code instead of a vector we just sneak thru the + * word generator coming out with just what we want. AND it does + * not matter if clustered_apic_mode is set or not. + */ +void smp_send_nmi_allbutself(void) +{ + send_IPI_allbutself(APIC_DM_NMI); +} +#endif + /* * Structure and data for smp_call_function(). This is designed to minimise * static memory requirements. It also looks cleaner. diff -puN arch/x86_64/kernel/traps.c~kgdb-x86_64-support arch/x86_64/kernel/traps.c --- devel/arch/x86_64/kernel/traps.c~kgdb-x86_64-support 2005-07-26 00:38:32.000000000 -0700 +++ devel-akpm/arch/x86_64/kernel/traps.c 2005-07-26 00:38:32.000000000 -0700 @@ -48,6 +48,9 @@ #include #include +#ifdef CONFIG_KGDB +#include +#endif extern struct gate_struct idt_table[256]; diff -puN /dev/null arch/x86_64/lib/kgdb_serial.c --- /dev/null 2003-09-15 06:40:47.000000000 -0700 +++ devel-akpm/arch/x86_64/lib/kgdb_serial.c 2005-07-26 00:38:32.000000000 -0700 @@ -0,0 +1,490 @@ +/* + * Serial interface GDB stub + * + * 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 + * and wangdi , based on + * code by San Mehat. + * + */ + +#include +#include +#include +#include +#include +#include +#include +#include +#include +#include +#include +#include +#include +#include +#include +#include +#include +#include +#include +#include +#include +#include +#include +#include +#include +#ifdef CONFIG_KGDB_USER_CONSOLE +extern void kgdb_console_finit(void); +#endif +#define PRNT_off +#define TEST_EXISTANCE +#ifdef PRNT +#define dbprintk(s) printk s +#else +#define dbprintk(s) +#endif +#define TEST_INTERRUPT_off +#ifdef TEST_INTERRUPT +#define intprintk(s) printk s +#else +#define intprintk(s) +#endif + +#define IRQ_T(info) ((info->flags & ASYNC_SHARE_IRQ) ? SA_SHIRQ : SA_INTERRUPT) + +#define GDB_BUF_SIZE 512 /* power of 2, please */ + +static char gdb_buf[GDB_BUF_SIZE]; +static int gdb_buf_in_inx; +static atomic_t gdb_buf_in_cnt; +static int gdb_buf_out_inx; + +struct async_struct *gdb_async_info; +static int gdb_async_irq; + +#define outb_px(a,b) outb_p(b,a) + +static void program_uart(struct async_struct *info); +static void write_char(struct async_struct *info, int chr); +/* + * Get a byte from the hardware data buffer and return it + */ +static int +read_data_bfr(struct async_struct *info) +{ + char it = inb_p(info->port + UART_LSR); + + if (it & UART_LSR_DR) + return (inb_p(info->port + UART_RX)); + /* + * If we have a framing error assume somebody messed with + * our uart. Reprogram it and send '-' both ways... + */ + if (it & 0xc) { + program_uart(info); + write_char(info, '-'); + return ('-'); + } + return (-1); + +} /* read_data_bfr */ + +/* + * Get a char if available, return -1 if nothing available. + * Empty the receive buffer first, then look at the interface hardware. + + * Locking here is a bit of a problem. We MUST not lock out communication + * if we are trying to talk to gdb about a kgdb entry. ON the other hand + * we can loose chars in the console pass thru if we don't lock. It is also + * possible that we could hold the lock or be waiting for it when kgdb + * NEEDS to talk. Since kgdb locks down the world, it does not need locks. + * We do, of course have possible issues with interrupting a uart operation, + * but we will just depend on the uart status to help keep that straight. + + */ +static spinlock_t uart_interrupt_lock = SPIN_LOCK_UNLOCKED; +#ifdef CONFIG_SMP +extern spinlock_t kgdb_spinlock; +#endif + +static int +read_char(struct async_struct *info) +{ + int chr; + unsigned long flags; + local_irq_save(flags); +#ifdef CONFIG_SMP + if (!spin_is_locked(&kgdb_spinlock)) { + spin_lock(&uart_interrupt_lock); + } +#endif + if (atomic_read(&gdb_buf_in_cnt) != 0) { /* intr routine has q'd chars */ + chr = gdb_buf[gdb_buf_out_inx++]; + gdb_buf_out_inx &= (GDB_BUF_SIZE - 1); + atomic_dec(&gdb_buf_in_cnt); + } else { + chr = read_data_bfr(info); + } +#ifdef CONFIG_SMP + if (!spin_is_locked(&kgdb_spinlock)) { + spin_unlock(&uart_interrupt_lock); + } +#endif + local_irq_restore(flags); + return (chr); +} + +/* + * Wait until the interface can accept a char, then write it. + */ +static void +write_char(struct async_struct *info, int chr) +{ + while (!(inb_p(info->port + UART_LSR) & UART_LSR_THRE)) ; + + outb_p(chr, info->port + UART_TX); + +} /* write_char */ + +/* + * Mostly we don't need a spinlock, but since the console goes + * thru here with interrutps on, well, we need to catch those + * chars. + */ +/* + * This is the receiver interrupt routine for the GDB stub. + * 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 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 tty_putDebugChar() which + * writes one byte after waiting for the interface to become + * ready. + * + * The debug stubs like to run with interrupts disabled since, + * after all, they run as a consequence of a breakpoint in + * the kernel. + * + * Perhaps someone who knows more about the tty driver than I + * care to learn can make this work for any low level serial + * driver. + */ +static irqreturn_t +gdb_interrupt(int irq, void *dev_id, struct pt_regs *regs) +{ + struct async_struct *info; + unsigned long flags; + + info = gdb_async_info; + if (!info || !info->tty || irq != gdb_async_irq) + return IRQ_NONE; + + local_irq_save(flags); + spin_lock(&uart_interrupt_lock); + do { + int chr = read_data_bfr(info); + intprintk(("Debug char on int: %x hex\n", chr)); + if (chr < 0) + continue; + + if (chr == 3) { /* Ctrl-C means remote interrupt */ + BREAKPOINT; + continue; + } + + if (atomic_read(&gdb_buf_in_cnt) >= GDB_BUF_SIZE) { + /* buffer overflow tosses early char */ + read_char(info); + } + gdb_buf[gdb_buf_in_inx++] = chr; + gdb_buf_in_inx &= (GDB_BUF_SIZE - 1); + } while (inb_p(info->port + UART_IIR) & UART_IIR_RDI); + spin_unlock(&uart_interrupt_lock); + local_irq_restore(flags); + return IRQ_HANDLED; +} /* gdb_interrupt */ + +/* + * Just a NULL routine for testing. + */ +void +gdb_null(void) +{ +} /* gdb_null */ + +/* These structure are filled in with values defined in asm/kgdb_local.h + */ +static struct serial_state state = SB_STATE; +static struct async_struct local_info = SB_INFO; +static int ok_to_enable_ints = 0; +static void kgdb_enable_ints_now(void); + +extern char *kgdb_version; +/* + * Hook an IRQ for KGDB. + * + * This routine is called from tty_putDebugChar, below. + */ +static int ints_disabled = 1; +int +gdb_hook_interrupt(struct async_struct *info, int verb) +{ + struct serial_state *state = info->state; + unsigned long flags; + int port; +#ifdef TEST_EXISTANCE + int scratch, scratch2; +#endif + + /* The above fails if memory managment is not set up yet. + * Rather than fail the set up, just keep track of the fact + * and pick up the interrupt thing later. + */ + gdb_async_info = info; + port = gdb_async_info->port; + gdb_async_irq = state->irq; + if (verb) { + printk("kgdb %s : port =%x, IRQ=%d, divisor =%d\n", + kgdb_version, + port, + gdb_async_irq, gdb_async_info->state->custom_divisor); + } + local_irq_save(flags); +#ifdef TEST_EXISTANCE + /* Existance test */ + /* Should not need all this, but just in case.... */ + + scratch = inb_p(port + UART_IER); + outb_px(port + UART_IER, 0); + outb_px(0xff, 0x080); + scratch2 = inb_p(port + UART_IER); + outb_px(port + UART_IER, scratch); + if (scratch2) { + printk + ("gdb_hook_interrupt: Could not clear IER, not a UART!\n"); + local_irq_restore(flags); + return 1; /* We failed; there's nothing here */ + } + scratch2 = inb_p(port + UART_LCR); + outb_px(port + UART_LCR, 0xBF); /* set up for StarTech test */ + outb_px(port + UART_EFR, 0); /* EFR is the same as FCR */ + outb_px(port + UART_LCR, 0); + outb_px(port + UART_FCR, UART_FCR_ENABLE_FIFO); + scratch = inb_p(port + UART_IIR) >> 6; + if (scratch == 1) { + printk("gdb_hook_interrupt: Undefined UART type!" + " Not a UART! \n"); + local_irq_restore(flags); + return 1; + } else { + dbprintk(("gdb_hook_interrupt: UART type " + "is %d where 0=16450, 2=16550 3=16550A\n", scratch)); + } + scratch = inb_p(port + UART_MCR); + outb_px(port + UART_MCR, UART_MCR_LOOP | scratch); + outb_px(port + UART_MCR, UART_MCR_LOOP | 0x0A); + scratch2 = inb_p(port + UART_MSR) & 0xF0; + outb_px(port + UART_MCR, scratch); + if (scratch2 != 0x90) { + printk("gdb_hook_interrupt: " + "Loop back test failed! Not a UART!\n"); + local_irq_restore(flags); + return scratch2 + 1000; /* force 0 to fail */ + } +#endif /* test existance */ + program_uart(info); + local_irq_restore(flags); + + return (0); + +} /* gdb_hook_interrupt */ + +static void +program_uart(struct async_struct *info) +{ + int port = info->port; + + (void) inb_p(port + UART_RX); + outb_px(port + UART_IER, 0); + + (void) inb_p(port + UART_RX); /* serial driver comments say */ + (void) inb_p(port + UART_IIR); /* this clears the interrupt regs */ + (void) inb_p(port + UART_MSR); + outb_px(port + UART_LCR, UART_LCR_WLEN8 | UART_LCR_DLAB); + outb_px(port + UART_DLL, info->state->custom_divisor & 0xff); /* LS */ + outb_px(port + UART_DLM, info->state->custom_divisor >> 8); /* MS */ + outb_px(port + UART_MCR, info->MCR); + + outb_px(port + UART_FCR, UART_FCR_ENABLE_FIFO | UART_FCR_TRIGGER_1 | UART_FCR_CLEAR_XMIT | UART_FCR_CLEAR_RCVR); /* set fcr */ + outb_px(port + UART_LCR, UART_LCR_WLEN8); /* reset DLAB */ + outb_px(port + UART_FCR, UART_FCR_ENABLE_FIFO | UART_FCR_TRIGGER_1); /* set fcr */ + if (!ints_disabled) { + intprintk(("KGDB: Sending %d to port %x offset %d\n", + gdb_async_info->IER, + (int) gdb_async_info->port, UART_IER)); + outb_px(gdb_async_info->port + UART_IER, gdb_async_info->IER); + } + return; +} + +/* + * 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 + * interface connection then it returns a bogus value which will + * almost certainly cause the system to hang. In the + */ +int kgdb_in_isr = 0; +int kgdb_in_lsr = 0; +extern spinlock_t kgdb_spinlock; + +/* Caller takes needed protections */ + +int +tty_getDebugChar(void) +{ + volatile int chr, dum, time, end_time; + + dbprintk(("tty_getDebugChar(port %x): ", gdb_async_info->port)); + + if (gdb_async_info == NULL) { + gdb_hook_interrupt(&local_info, 0); + } + /* + * This trick says if we wait a very long time and get + * no char, return the -1 and let the upper level deal + * with it. + */ + rdtsc(dum, time); + end_time = time + 2; + while (((chr = read_char(gdb_async_info)) == -1) && + (end_time - time) > 0) { + rdtsc(dum, time); + }; + /* + * This covers our butts if some other code messes with + * our uart, hay, it happens :o) + */ + if (chr == -1) + program_uart(gdb_async_info); + + dbprintk(("%c\n", chr > ' ' && chr < 0x7F ? chr : ' ')); + return (chr); + +} /* tty_getDebugChar */ + +static int count = 3; +static spinlock_t one_at_atime = SPIN_LOCK_UNLOCKED; + +static int __init +kgdb_enable_ints(void) +{ + set_debug_traps(); + if (kgdboe) { + return 0; + } + if (gdb_async_info == NULL) { + gdb_hook_interrupt(&local_info, 1); + } + ok_to_enable_ints = 1; + kgdb_enable_ints_now(); +#ifdef CONFIG_KGDB_USER_CONSOLE + kgdb_console_finit(); +#endif + return 0; +} + +#ifdef CONFIG_SERIAL_8250 +void shutdown_for_kgdb(struct async_struct *gdb_async_info); +#endif + +#define kgdb_mem_init_done() (1) + +static void +kgdb_enable_ints_now(void) +{ + if (!spin_trylock(&one_at_atime)) + return; + if (!ints_disabled) + goto exit; + if (kgdb_mem_init_done() && + ints_disabled) { /* don't try till mem init */ +#ifdef CONFIG_SERIAL_8250 + /* + * The ifdef here allows the system to be configured + * without the serial driver. + * Don't make it a module, however, it will steal the port + */ + shutdown_for_kgdb(gdb_async_info); +#endif + ints_disabled = request_irq(gdb_async_info->state->irq, + gdb_interrupt, + IRQ_T(gdb_async_info), + "KGDB-stub", NULL); + intprintk(("KGDB: request_irq returned %d\n", ints_disabled)); + } + if (!ints_disabled) { + intprintk(("KGDB: Sending %d to port %x offset %d\n", + gdb_async_info->IER, + (int) gdb_async_info->port, UART_IER)); + outb_px(gdb_async_info->port + UART_IER, gdb_async_info->IER); + } + exit: + spin_unlock(&one_at_atime); +} + +/* + * 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 + * interface connection then it simply returns to its caller, having + * pretended to send the char. Caller takes needed protections. + */ +void +tty_putDebugChar(int chr) +{ + 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)); + + if (gdb_async_info == NULL) { + gdb_hook_interrupt(&local_info, 0); + } + + write_char(gdb_async_info, chr); /* this routine will wait */ + count = (chr == '#') ? 0 : count + 1; + if ((count == 2)) { /* try to enable after */ + if (ints_disabled & ok_to_enable_ints) + kgdb_enable_ints_now(); /* try to enable after */ + + /* We do this a lot because, well we really want to get these + * interrupts. The serial driver will clear these bits when it + * initializes the chip. Every thing else it does is ok, + * but this. + */ + if (!ints_disabled) { + outb_px(gdb_async_info->port + UART_IER, + gdb_async_info->IER); + } + } + +} /* tty_putDebugChar */ + +/* + * This does nothing for the serial port, since it doesn't buffer. + */ + +void tty_flushDebugChar(void) +{ +} + +module_init(kgdb_enable_ints); diff -puN arch/x86_64/lib/Makefile~kgdb-x86_64-support arch/x86_64/lib/Makefile --- devel/arch/x86_64/lib/Makefile~kgdb-x86_64-support 2005-07-26 00:38:32.000000000 -0700 +++ devel-akpm/arch/x86_64/lib/Makefile 2005-07-26 00:38:32.000000000 -0700 @@ -12,3 +12,4 @@ lib-y := csum-partial.o csum-copy.o csum lib-y += memcpy.o memmove.o memset.o copy_user.o lib-$(CONFIG_HAVE_DEC_LOCK) += dec_and_lock.o +lib-$(CONFIG_KGDB) += kgdb_serial.o diff -puN /dev/null include/asm-x86_64/kgdb.h --- /dev/null 2003-09-15 06:40:47.000000000 -0700 +++ devel-akpm/include/asm-x86_64/kgdb.h 2005-07-26 00:38:32.000000000 -0700 @@ -0,0 +1,71 @@ +#ifndef __KGDB +#define __KGDB + +/* + * This file should not include ANY others. This makes it usable + * most anywhere without the fear of include order or inclusion. + * Make it so! + * + * This file may be included all the time. It is only active if + * CONFIG_KGDB is defined, otherwise it stubs out all the macros + * and entry points. + */ +#if defined(CONFIG_KGDB) && !defined(__ASSEMBLY__) + +extern void breakpoint(void); +#define INIT_KGDB_INTS kgdb_enable_ints() + +#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 + * when a trap occurs. + * + * Return values are, at present, undefined. + * + * The debug hook routine does not necessarily return to its caller. + * It has the register image and thus may choose to resume execution + * anywhere it pleases. + */ +struct pt_regs; + +extern int kgdb_handle_exception(int trapno, + int signo, int err_code, struct pt_regs *regs); +extern int in_kgdb(struct pt_regs *regs); + +extern void set_debug_traps(void); + +#ifdef CONFIG_KGDB_TS +void kgdb_tstamp(int line, char *source, int data0, int data1); +/* + * This is the time stamp function. The macro adds the source info and + * does a cast on the data to allow most any 32-bit value. + */ + +#define kgdb_ts(data0,data1) kgdb_tstamp(__LINE__,__FILE__,(int)data0,(int)data1) +#else +#define kgdb_ts(data0,data1) +#endif +#else /* CONFIG_KGDB && ! __ASSEMBLY__ ,stubs follow... */ +#ifndef BREAKPOINT +#define BREAKPOINT +#endif +#define kgdb_ts(data0,data1) +#define in_kgdb (0) +#define kgdb_handle_exception +#define breakpoint +#define INIT_KGDB_INTS +#define kgdb_process_breakpoint() do {} while(0) + +#endif +#endif /* __KGDB */ diff -puN /dev/null include/asm-x86_64/kgdb_local.h --- /dev/null 2003-09-15 06:40:47.000000000 -0700 +++ devel-akpm/include/asm-x86_64/kgdb_local.h 2005-07-26 00:38:32.000000000 -0700 @@ -0,0 +1,102 @@ +#ifndef __KGDB_LOCAL +#define ___KGDB_LOCAL +#include +#include +#include +#include +#include +#include +#include +#include + +#define PORT 0x3f8 +#ifdef CONFIG_KGDB_PORT +#undef PORT +#define PORT CONFIG_KGDB_PORT +#endif +#define IRQ 4 +#ifdef CONFIG_KGDB_IRQ +#undef IRQ +#define IRQ CONFIG_KGDB_IRQ +#endif +#define SB_CLOCK 1843200 +#define SB_BASE (SB_CLOCK/16) +#define SB_BAUD9600 SB_BASE/9600 +#define SB_BAUD192 SB_BASE/19200 +#define SB_BAUD384 SB_BASE/38400 +#define SB_BAUD576 SB_BASE/57600 +#define SB_BAUD1152 SB_BASE/115200 +#ifdef CONFIG_KGDB_9600BAUD +#define SB_BAUD SB_BAUD9600 +#endif +#ifdef CONFIG_KGDB_19200BAUD +#define SB_BAUD SB_BAUD192 +#endif +#ifdef CONFIG_KGDB_38400BAUD +#define SB_BAUD SB_BAUD384 +#endif +#ifdef CONFIG_KGDB_57600BAUD +#define SB_BAUD SB_BAUD576 +#endif +#ifdef CONFIG_KGDB_115200BAUD +#define SB_BAUD SB_BAUD1152 +#endif +#ifndef SB_BAUD +#define SB_BAUD SB_BAUD1152 /* Start with this if not given */ +#endif + +#ifndef CONFIG_X86_TSC +#undef rdtsc +#define rdtsc(a,b) if (a++ > 10000){a = 0; b++;} +#undef rdtscll +#define rdtscll(s) s++ +#endif + +#ifdef _raw_read_unlock /* must use a name that is "define"ed, not an inline */ +#undef spin_lock +#undef spin_trylock +#undef spin_unlock +#define spin_lock _raw_spin_lock +#define spin_trylock _raw_spin_trylock +#define spin_unlock _raw_spin_unlock +#else +#endif +#undef spin_unlock_wait +#define spin_unlock_wait(x) do { cpu_relax(); barrier();} \ + while(spin_is_locked(x)) + +#define SB_IER 1 +#define SB_MCR UART_MCR_OUT2 | UART_MCR_DTR | UART_MCR_RTS + +#define FLAGS 0 +#define SB_STATE { \ + magic: SSTATE_MAGIC, \ + baud_base: SB_BASE, \ + port: PORT, \ + irq: IRQ, \ + flags: FLAGS, \ + custom_divisor:SB_BAUD} +#define SB_INFO { \ + magic: SERIAL_MAGIC, \ + port: PORT,0,FLAGS, \ + state: &state, \ + tty: (struct tty_struct *)&state, \ + IER: SB_IER, \ + MCR: SB_MCR} +extern void putDebugChar(int); +/* RTAI support needs us to really stop/start interrupts */ + +#define kgdb_sti() __asm__ __volatile__("sti": : :"memory") +#define kgdb_cli() __asm__ __volatile__("cli": : :"memory") +#define kgdb_local_save_flags(x) __asm__ __volatile__(\ + "pushfl ; popl %0":"=g" (x): /* no input */) +#define kgdb_local_irq_restore(x) __asm__ __volatile__(\ + "pushl %0 ; popfl": \ + /* no output */ :"g" (x):"memory", "cc") +#define kgdb_local_irq_save(x) kgdb_local_save_flags(x); kgdb_cli() + +#ifdef CONFIG_SERIAL +extern void shutdown_for_kgdb(struct async_struct *info); +#endif +#define INIT_KDEBUG putDebugChar("+"); +#endif /* __KGDB_LOCAL */ diff -puN include/linux/config.h~kgdb-x86_64-support include/linux/config.h --- devel/include/linux/config.h~kgdb-x86_64-support 2005-07-26 00:38:32.000000000 -0700 +++ devel-akpm/include/linux/config.h 2005-07-26 00:38:32.000000000 -0700 @@ -2,7 +2,7 @@ #define _LINUX_CONFIG_H #include -#if defined(__i386__) && !defined(IN_BOOTLOADER) +#ifdef CONFIG_X86 #include #endif diff -puN init/main.c~kgdb-x86_64-support init/main.c --- devel/init/main.c~kgdb-x86_64-support 2005-07-26 00:38:32.000000000 -0700 +++ devel-akpm/init/main.c 2005-07-26 00:38:32.000000000 -0700 @@ -463,13 +463,13 @@ asmlinkage void __init start_kernel(void preempt_disable(); build_all_zonelists(); page_alloc_init(); + trap_init(); printk(KERN_NOTICE "Kernel command line: %s\n", saved_command_line); parse_early_param(); parse_args("Booting kernel", command_line, __start___param, __stop___param - __start___param, &unknown_bootoption); sort_main_extable(); - trap_init(); rcu_init(); init_IRQ(); pidhash_init(); diff -puN Makefile~kgdb-x86_64-support Makefile --- devel/Makefile~kgdb-x86_64-support 2005-07-26 00:38:32.000000000 -0700 +++ devel-akpm/Makefile 2005-07-26 00:38:32.000000000 -0700 @@ -525,6 +525,7 @@ endif ifdef CONFIG_DEBUG_INFO CFLAGS += -g +AFLAGS += -g endif include $(srctree)/arch/$(ARCH)/Makefile diff -puN arch/x86_64/Kconfig.debug~kgdb-x86_64-support arch/x86_64/Kconfig.debug --- devel/arch/x86_64/Kconfig.debug~kgdb-x86_64-support 2005-07-26 00:38:32.000000000 -0700 +++ devel-akpm/arch/x86_64/Kconfig.debug 2005-07-26 00:38:32.000000000 -0700 @@ -51,7 +51,6 @@ config IOMMU_LEAK Add a simple leak tracer to the IOMMU code. This is useful when you are debugging a buggy device driver that leaks IOMMU mappings. -#config X86_REMOTE_DEBUG -# bool "kgdb debugging stub" +source "arch/x86_64/Kconfig.kgdb" endmenu diff -puN drivers/serial/8250.c~kgdb-x86_64-support drivers/serial/8250.c _