i've uploaded kgdb-light -v9, it can be pulled from:
git://git.kernel.org/pub/scm/linux/kernel/git/mingo/linux-2.6-kgdb.git
find the shortlog, diffstat, full patch below.
There are a number of changes in -v9 - a patch from Jason to clean up
kernel-messages-over-the-kgdb-console behavior and a bugfix from Jan.
Here's how i addressed the review feedback from Andi Kleen:
fixed. (That code is gone now - the pt_regs passed in to the notifier
points to the right kind of register context already, so the whole
shadow task business on 64-bit was an unnecessary complication - as you
suspected it. With it went another bunch of kernel/kgdb.c complication
as well.)
i reworked and cleaned up all the kgdb locking code completely. No more
NR_CPUS spinlocks, there's now proper use of barriers, etc. No more
silly "timeouts" for locking either ... There's now a very well-defined
and clean locking state-machine for the primary CPU and the secondary
CPUs. I re-tested it all on SMP hardware as well.
i fixed the shadow thread bits which where harmless but unnecessary.
exotic indeed - but nevertheless i fixed this too.
previously Mark indicated some sort of sprintf return value breakage he
observed, and kgdb would rely on sprintf return values so i'm inclined
to leave it as-is. We can fix that later, it's not critical.
i fixed them too.
thanks for your suggestions, anything else you can think of?
Ingo
------------------>
Ingo Molnar (3):
pids: add pid_max prototype
uaccess: add probe_kernel_write()
x86: kgdb support
Jason Wessel (3):
kgdb: core
consoles: polling support, kgdboc
kgdb: document parameters
Documentation/kernel-parameters.txt | 5 +
arch/x86/Kconfig | 1 +
arch/x86/kernel/Makefile | 1 +
arch/x86/kernel/kgdb.c | 555 ++++++++++++
drivers/char/tty_io.c | 47 +
drivers/serial/8250.c | 58 ++
drivers/serial/Kconfig | 3 +
drivers/serial/Makefile | 1 +
drivers/serial/kgdboc.c | 163 ++++
drivers/serial/serial_core.c | 70 ++-
include/asm-x86/kgdb.h | 81 ++
include/linux/kgdb.h | 271 ++++++
include/linux/pid.h | 2 +
include/linux/serial_core.h | 4 +
include/linux/tty_driver.h | 12 +
include/linux/uaccess.h | 22 +
kernel/Makefile | 1 +
kernel/kgdb.c | 1663 +++++++++++++++++++++++++++++++++++
kernel/sysctl.c | 2 +-
lib/Kconfig.debug | 2 +
lib/Kconfig.kgdb | 27 +
mm/Makefile | 2 +-
mm/maccess.c | 49 +
23 files changed, 3037 insertions(+), 5 deletions(-)
create mode 100644 arch/x86/kernel/kgdb.c
create mode 100644 drivers/serial/kgdboc.c
create mode 100644 include/asm-x86/kgdb.h
create mode 100644 include/linux/kgdb.h
create mode 100644 kernel/kgdb.c
create mode 100644 lib/Kconfig.kgdb
create mode 100644 mm/maccess.c
diff --git a/Documentation/kernel-parameters.txt b/Documentation/kernel-parameters.txt
index a4fc7fc..6e97307 100644
--- a/Documentation/kernel-parameters.txt
+++ b/Documentation/kernel-parameters.txt
@@ -930,6 +930,11 @@ and is between 256 and 4096 characters. It is defined in the file
kstack=N [X86-32,X86-64] Print N words from the kernel stack
in oops dumps.
+ kgdboc= [HW] kgdb over consoles.
+ Requires a tty driver that supports console polling.
+ (only serial suported for now)
+ Format: <serial_device>[,baud]
+
l2cr= [PPC]
lapic [X86-32,APIC] Enable the local APIC even if BIOS
diff --git a/arch/x86/Kconfig b/arch/x86/Kconfig
index aaed1a3..c8dd8f9 100644
--- a/arch/x86/Kconfig
+++ b/arch/x86/Kconfig
@@ -21,6 +21,7 @@ config X86
select HAVE_IDE
select HAVE_OPROFILE
select HAVE_KPROBES
+ select HAVE_ARCH_KGDB
config GENERIC_LOCKBREAK
def_bool n
diff --git a/arch/x86/kernel/Makefile b/arch/x86/kernel/Makefile
index 76ec0f8..4cd39cd 100644
--- a/arch/x86/kernel/Makefile
+++ b/arch/x86/kernel/Makefile
@@ -58,6 +58,7 @@ obj-$(CONFIG_MODULES) += module_$(BITS).o
obj-$(CONFIG_ACPI_SRAT) += srat_32.o
obj-$(CONFIG_EFI) += efi.o efi_$(BITS).o efi_stub_$(BITS).o
obj-$(CONFIG_DOUBLEFAULT) += doublefault_32.o
+obj-$(CONFIG_KGDB) += kgdb.o
obj-$(CONFIG_VM86) += vm86_32.o
obj-$(CONFIG_EARLY_PRINTK) += early_printk.o
diff --git a/arch/x86/kernel/kgdb.c b/arch/x86/kernel/kgdb.c
new file mode 100644
index 0000000..18034d5
--- /dev/null
+++ b/arch/x86/kernel/kgdb.c
@@ -0,0 +1,555 @@
+/*
+ * 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) 2004 Amit S. Kale <amitkale@linsyssoft.com>
+ * Copyright (C) 2000-2001 VERITAS Software Corporation.
+ * Copyright (C) 2002 Andi Kleen, SuSE Labs
+ * Copyright (C) 2004 LinSysSoft Technologies Pvt. Ltd.
+ * Copyright (C) 2007 MontaVista Software, Inc.
+ * Copyright (C) 2007-2008 Jason Wessel, Wind River Systems, Inc.
+ */
+/****************************************************************************
+ * Contributor: Lake Stevens Instrument Division$
+ * Written by: Glenn Engel $
+ * Updated by: Amit Kale<akale@veritas.com>
+ * Updated by: Tom Rini <trini@kernel.crashing.org>
+ * Updated by: Jason Wessel <jason.wessel@windriver.com>
+ * Modified for 386 by Jim Kingdon, Cygnus Support.
+ * Origianl kgdb, compatibility with 2.1.xx kernel by
+ * David Grothe <dave@gcom.com>
+ * Integrated into 2.2.5 kernel by Tigran Aivazian <tigran@sco.com>
+ * X86_64 changes from Andi Kleen's patch merged by Jim Houston
+ */
+#include <linux/spinlock.h>
+#include <linux/kdebug.h>
+#include <linux/string.h>
+#include <linux/kernel.h>
+#include <linux/ptrace.h>
+#include <linux/sched.h>
+#include <linux/delay.h>
+#include <linux/kgdb.h>
+#include <linux/init.h>
+#include <linux/smp.h>
+
+#include <asm/apicdef.h>
+#include <asm/system.h>
+
+#ifdef CONFIG_X86_32
+# include <mach_ipi.h>
+#else
+# include <asm/mach_apic.h>
+#endif
+
+/*
+ * Put the error code here just in case the user cares:
+ */
+static int gdb_x86errcode;
+
+/*
+ * Likewise, the vector number here (since GDB only gets the signal
+ * number through the usual means, and that's not very specific):
+ */
+static int gdb_x86vector = -1;
+
+/**
+ * pt_regs_to_gdb_regs - Convert ptrace regs to GDB regs
+ * @gdb_regs: A pointer to hold the registers in the order GDB wants.
+ * @regs: The &struct pt_regs of the current process.
+ *
+ * Convert the pt_regs in @regs into the format for registers that
+ * GDB expects, stored in @gdb_regs.
+ */
+void pt_regs_to_gdb_regs(unsigned long *gdb_regs, struct pt_regs *regs)
+{
+ gdb_regs[GDB_AX] = regs->ax;
+ gdb_regs[GDB_BX] = regs->bx;
+ gdb_regs[GDB_CX] = regs->cx;
+ gdb_regs[GDB_DX] = regs->dx;
+ gdb_regs[GDB_SI] = regs->si;
+ gdb_regs[GDB_DI] = regs->di;
+ gdb_regs[GDB_BP] = regs->bp;
+ gdb_regs[GDB_PS] = regs->flags;
+ gdb_regs[GDB_PC] = regs->ip;
+#ifdef CONFIG_X86_32
+ gdb_regs[GDB_DS] = regs->ds;
+ gdb_regs[GDB_ES] = regs->es;
+ gdb_regs[GDB_CS] = regs->cs;
+ gdb_regs[GDB_SS] = __KERNEL_DS;
+ gdb_regs[GDB_FS] = 0xFFFF;
+ gdb_regs[GDB_GS] = 0xFFFF;
+#else
+ gdb_regs[GDB_R8] = regs->r8;
+ gdb_regs[GDB_R9] = regs->r9;
+ gdb_regs[GDB_R10] = regs->r10;
+ gdb_regs[GDB_R11] = regs->r11;
+ gdb_regs[GDB_R12] = regs->r12;
+ gdb_regs[GDB_R13] = regs->r13;
+ gdb_regs[GDB_R14] = regs->r14;
+ gdb_regs[GDB_R15] = regs->r15;
+#endif
+ gdb_regs[GDB_SP] = regs->sp;
+}
+
+/**
+ * sleeping_thread_to_gdb_regs - Convert ptrace regs to GDB regs
+ * @gdb_regs: A pointer to hold the registers in the order GDB wants.
+ * @p: The &struct task_struct of the desired process.
+ *
+ * Convert the register values of the sleeping process in @p to
+ * the format that GDB expects.
+ * This function is called when kgdb does not have access to the
+ * &struct pt_regs and therefore it should fill the gdb registers
+ * @gdb_regs with what has been saved in &struct thread_struct
+ * thread field during switch_to.
+ */
+void sleeping_thread_to_gdb_regs(unsigned long *gdb_regs, struct task_struct *p)
+{
+ gdb_regs[GDB_AX] = 0;
+ gdb_regs[GDB_BX] = 0;
+ gdb_regs[GDB_CX] = 0;
+ gdb_regs[GDB_DX] = 0;
+ gdb_regs[GDB_SI] = 0;
+ gdb_regs[GDB_DI] = 0;
+ gdb_regs[GDB_BP] = *(unsigned long *)p->thread.sp;
+#ifdef CONFIG_X86_32
+ gdb_regs[GDB_DS] = __KERNEL_DS;
+ gdb_regs[GDB_ES] = __KERNEL_DS;
+ gdb_regs[GDB_PS] = 0;
+ gdb_regs[GDB_CS] = __KERNEL_CS;
+ gdb_regs[GDB_PC] = p->thread.ip;
+ gdb_regs[GDB_SS] = __KERNEL_DS;
+ gdb_regs[GDB_FS] = 0xFFFF;
+ gdb_regs[GDB_GS] = 0xFFFF;
+#else
+ gdb_regs[GDB_PS] = *(unsigned long *)(p->thread.sp + 8);
+ gdb_regs[GDB_PC] = 0;
+ gdb_regs[GDB_R8] = 0;
+ gdb_regs[GDB_R9] = 0;
+ gdb_regs[GDB_R10] = 0;
+ gdb_regs[GDB_R11] = 0;
+ gdb_regs[GDB_R12] = 0;
+ gdb_regs[GDB_R13] = 0;
+ gdb_regs[GDB_R14] = 0;
+ gdb_regs[GDB_R15] = 0;
+#endif
+ gdb_regs[GDB_SP] = p->thread.sp;
+}
+
+/**
+ * gdb_regs_to_pt_regs - Convert GDB regs to ptrace regs.
+ * @gdb_regs: A pointer to hold the registers we've received from GDB.
+ * @regs: A pointer to a &struct pt_regs to hold these values in.
+ *
+ * Convert the GDB regs in @gdb_regs into the pt_regs, and store them
+ * in @regs.
+ */
+void gdb_regs_to_pt_regs(unsigned long *gdb_regs, struct pt_regs *regs)
+{
+ regs->ax = gdb_regs[GDB_AX];
+ regs->bx = gdb_regs[GDB_BX];
+ regs->cx = gdb_regs[GDB_CX];
+ regs->dx = gdb_regs[GDB_DX];
+ regs->si = gdb_regs[GDB_SI];
+ regs->di = gdb_regs[GDB_DI];
+ regs->bp = gdb_regs[GDB_BP];
+ regs->flags = gdb_regs[GDB_PS];
+ regs->ip = gdb_regs[GDB_PC];
+#ifdef CONFIG_X86_32
+ regs->ds = gdb_regs[GDB_DS];
+ regs->es = gdb_regs[GDB_ES];
+ regs->cs = gdb_regs[GDB_CS];
+#else
+ regs->r8 = gdb_regs[GDB_R8];
+ regs->r9 = gdb_regs[GDB_R9];
+ regs->r10 = gdb_regs[GDB_R10];
+ regs->r11 = gdb_regs[GDB_R11];
+ regs->r12 = gdb_regs[GDB_R12];
+ regs->r13 = gdb_regs[GDB_R13];
+ regs->r14 = gdb_regs[GDB_R14];
+ regs->r15 = gdb_regs[GDB_R15];
+#endif
+}
+
+static struct hw_breakpoint {
+ unsigned enabled;
+ unsigned type;
+ unsigned len;
+ unsigned long addr;
+} breakinfo[4];
+
+static void kgdb_correct_hw_break(void)
+{
+ unsigned long dr7;
+ int correctit = 0;
+ int breakbit;
+ int breakno;
+
+ get_debugreg(dr7, 7);
+ for (breakno = 0; breakno < 4; 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) <<
+ ((breakno << 2) + 16);
+ if (breakno >= 0 && breakno <= 3)
+ set_debugreg(breakinfo[breakno].addr, breakno);
+
+ } else {
+ if ((dr7 & breakbit) && !breakinfo[breakno].enabled) {
+ correctit = 1;
+ dr7 &= ~breakbit;
+ dr7 &= ~(0xf0000 << (breakno << 2));
+ }
+ }
+ }
+ if (correctit)
+ set_debugreg(dr7, 7);
+}
+
+static int
+kgdb_remove_hw_break(unsigned long addr, int len, enum kgdb_bptype bptype)
+{
+ int i;
+
+ for (i = 0; i < 4; i++)
+ if (breakinfo[i].addr == addr && breakinfo[i].enabled)
+ break;
+ if (i == 4)
+ return -1;
+
+ breakinfo[i].enabled = 0;
+
+ return 0;
+}
+
+static void kgdb_remove_all_hw_break(void)
+{
+ int i;
+
+ for (i = 0; i < 4; i++)
+ memset(&breakinfo[i], 0, sizeof(struct hw_breakpoint));
+}
+
+static int
+kgdb_set_hw_break(unsigned long addr, int len, enum kgdb_bptype bptype)
+{
+ unsigned type;
+ int i;
+
+ for (i = 0; i < 4; i++)
+ if (!breakinfo[i].enabled)
+ break;
+ if (i == 4)
+ return -1;
+
+ switch (bptype) {
+ case BP_HARDWARE_BREAKPOINT:
+ type = 0;
+ len = 1;
+ break;
+ case BP_WRITE_WATCHPOINT:
+ type = 1;
+ break;
+ case BP_ACCESS_WATCHPOINT:
+ type = 3;
+ break;
+ default:
+ return -1;
+ }
+
+ if (len == 1 || len == 2 || len == 4)
+ breakinfo[i].len = len - 1;
+ else
+ return -1;
+
+ breakinfo[i].enabled = 1;
+ breakinfo[i].addr = addr;
+ breakinfo[i].type = type;
+
+ return 0;
+}
+
+/**
+ * kgdb_disable_hw_debug - Disable hardware debugging while we in kgdb.
+ * @regs: Current &struct pt_regs.
+ *
+ * This function will be called if the particular architecture must
+ * disable hardware debugging while it is processing gdb packets or
+ * handling exception.
+ */
+void kgdb_disable_hw_debug(struct pt_regs *regs)
+{
+ /* Disable hardware debugging while we are in kgdb: */
+ set_debugreg(0UL, 7);
+}
+
+/**
+ * kgdb_post_primary_code - Save error vector/code numbers.
+ * @regs: Original pt_regs.
+ * @e_vector: Original error vector.
+ * @err_code: Original error code.
+ *
+ * This is needed on architectures which support SMP and KGDB.
+ * This function is called after all the slave cpus have been put
+ * to a know spin state and the primary CPU has control over KGDB.
+ */
+void kgdb_post_primary_code(struct pt_regs *regs, int e_vector, int err_code)
+{
+ /* primary processor is completely in the debugger */
+ gdb_x86vector = e_vector;
+ gdb_x86errcode = err_code;
+}
+
+#ifdef CONFIG_SMP
+/**
+ * kgdb_roundup_cpus - Get other CPUs into a holding pattern
+ * @flags: Current IRQ state
+ *
+ * On SMP systems, we need to get the attention of the other CPUs
+ * and get them be in a known state. This should do what is needed
+ * to get the other CPUs to call kgdb_wait(). Note that on some arches,
+ * the NMI approach is not used for rounding up all the CPUs. For example,
+ * in case of MIPS, smp_call_function() is used to roundup CPUs. In
+ * this case, we have to make sure that interrupts are enabled before
+ * calling smp_call_function(). The argument to this function is
+ * the flags that will be used when restoring the interrupts. There is
+ * local_irq_save() call before kgdb_roundup_cpus().
+ *
+ * On non-SMP systems, this is not called.
+ */
+void kgdb_roundup_cpus(unsigned long flags)
+{
+ send_IPI_allbutself(APIC_DM_NMI);
+}
+#endif
+
+/**
+ * kgdb_arch_handle_exception - Handle architecture specific GDB packets.
+ * @vector: The error vector of the exception that happened.
+ * @signo: The signal number of the exception that happened.
+ * @err_code: The error code of the exception that happened.
+ * @remcom_in_buffer: The buffer of the packet we have read.
+ * @remcom_out_buffer: The buffer of %BUFMAX bytes to write a packet into.
+ * @regs: The &struct pt_regs of the current process.
+ *
+ * This function MUST handle the 'c' and 's' command packets,
+ * as well packets to set / remove a hardware breakpoint, if used.
+ * If there are additional packets which the hardware needs to handle,
+ * they are handled here. The code should return -1 if it wants to
+ * process more packets, and a %0 or %1 if it wants to exit from the
+ * kgdb callback.
+ */
+int kgdb_arch_handle_exception(int e_vector, int signo, int err_code,
+ char *remcomInBuffer, char *remcomOutBuffer,
+ struct pt_regs *linux_regs)
+{
+ unsigned long addr;
+ unsigned long dr6;
+ char *ptr;
+ int newPC;
+
+ switch (remcomInBuffer[0]) {
+ case 'c':
+ case 's':
+ /* try to read optional parameter, pc unchanged if no parm */
+ ptr = &remcomInBuffer[1];
+ if (kgdb_hex2long(&ptr, &addr))
+ linux_regs->ip = addr;
+ newPC = linux_regs->ip;
+
+ /* clear the trace bit */
+ linux_regs->flags &= ~TF_MASK;
+ atomic_set(&kgdb_cpu_doing_single_step, -1);
+
+ /* set the trace bit if we're stepping */
+ if (remcomInBuffer[0] == 's') {
+ linux_regs->flags |= TF_MASK;
+ kgdb_single_step = 1;
+ if (kgdb_contthread) {
+ atomic_set(&kgdb_cpu_doing_single_step,
+ raw_smp_processor_id());
+ }
+ }
+
+ get_debugreg(dr6, 6);
+ if (!(dr6 & 0x4000)) {
+ int breakno;
+
+ for (breakno = 0; breakno < 4; breakno++) {
+ if (dr6 & (1 << breakno) &&
+ breakinfo[breakno].type == 0) {
+ /* Set restore flag: */
+ linux_regs->flags |= X86_EFLAGS_RF;
+ break;
+ }
+ }
+ }
+ set_debugreg(0UL, 6);
+ kgdb_correct_hw_break();
+
+ return 0;
+ }
+
+ /* this means that we do not want to exit from the handler: */
+ return -1;
+}
+
+static inline int
+single_step_cont(struct pt_regs *regs, struct die_args *args)
+{
+ /*
+ * Single step exception from kernel space to user space so
+ * eat the exception and continue the process:
+ */
+ printk(KERN_ERR "KGDB: trap/step from kernel to user space, "
+ "resuming...\n");
+ kgdb_arch_handle_exception(args->trapnr, args->signr,
+ args->err, "c", "", regs);
+
+ return NOTIFY_STOP;
+}
+
+static int __kgdb_notify(struct die_args *args, unsigned long cmd)
+{
+ struct pt_regs *regs = args->regs;
+
+ switch (cmd) {
+ case DIE_NMI:
+ if (atomic_read(&kgdb_active) != -1) {
+ /* KGDB CPU roundup */
+ kgdb_nmicallback(raw_smp_processor_id(), regs);
+ return NOTIFY_STOP;
+ }
+ return NOTIFY_DONE;
+
+ case DIE_NMI_IPI:
+ if (atomic_read(&kgdb_active) != -1) {
+ /* KGDB CPU roundup: */
+ if (kgdb_nmicallback(raw_smp_processor_id(), regs))
+ return NOTIFY_DONE;
+ return NOTIFY_STOP;
+ }
+ return NOTIFY_DONE;
+
+ case DIE_NMIWATCHDOG:
+ if (atomic_read(&kgdb_active) != -1) {
+ /* KGDB CPU roundup: */
+ kgdb_nmicallback(raw_smp_processor_id(), regs);
+ return NOTIFY_STOP;
+ }
+ /* Enter debugger: */
+ break;
+
+ case DIE_DEBUG:
+ if (atomic_read(&kgdb_cpu_doing_single_step) ==
+ raw_smp_processor_id() &&
+ user_mode(regs))
+ return single_step_cont(regs, args);
+ /* fall through */
+ default:
+ if (user_mode(regs))
+ return NOTIFY_DONE;
+ }
+
+ if (kgdb_handle_exception(args->trapnr, args->signr, args->err, regs))
+ return NOTIFY_DONE;
+
+ return NOTIFY_STOP;
+}
+
+static int
+kgdb_notify(struct notifier_block *self, unsigned long cmd, void *ptr)
+{
+ unsigned long flags;
+ int ret;
+
+ local_irq_save(flags);
+ ret = __kgdb_notify(ptr, cmd);
+ local_irq_restore(flags);
+
+ return ret;
+}
+
+static struct notifier_block kgdb_notifier = {
+ .notifier_call = kgdb_notify,
+
+ /*
+ * Lowest-prio notifier priority, we want to be notified last:
+ */
+ .priority = -INT_MAX,
+};
+
+/**
+ * kgdb_arch_init - Perform any architecture specific initalization.
+ *
+ * This function will handle the initalization of any architecture
+ * specific callbacks.
+ */
+int kgdb_arch_init(void)
+{
+ return register_die_notifier(&kgdb_notifier);
+}
+
+/**
+ * kgdb_arch_exit - Perform any architecture specific uninitalization.
+ *
+ * This function will handle the uninitalization of any architecture
+ * specific callbacks, for dynamic registration and unregistration.
+ */
+void kgdb_arch_exit(void)
+{
+ unregister_die_notifier(&kgdb_notifier);
+}
+
+/**
+ *
+ * kgdb_skipexception - Bail of of KGDB when we've been triggered.
+ * @exception: Exception vector number
+ * @regs: Current &struct pt_regs.
+ *
+ * On some architectures we need to skip a breakpoint exception when
+ * it occurs after a breakpoint has been removed.
+ *
+ * Skip an int3 exception when it occurs after a breakpoint has been
+ * removed. Backtrack eip by 1 since the int3 would have caused it to
+ * increment by 1.
+ */
+int kgdb_skipexception(int exception, struct pt_regs *regs)
+{
+ if (exception == 3 && kgdb_isremovedbreak(regs->ip - 1)) {
+ regs->ip -= 1;
+ return 1;
+ }
+ return 0;
+}
+
+unsigned long kgdb_arch_pc(int exception, struct pt_regs *regs)
+{
+ if (exception == 3)
+ return instruction_pointer(regs) - 1;
+ return instruction_pointer(regs);
+}
+
+struct kgdb_arch arch_kgdb_ops = {
+ /* Breakpoint instruction: */
+ .gdb_bpt_instr = { 0xcc },
+ .flags = KGDB_HW_BREAKPOINT,
+ .set_hw_breakpoint = kgdb_set_hw_break,
+ .remove_hw_breakpoint = kgdb_remove_hw_break,
+ .remove_all_hw_break = kgdb_remove_all_hw_break,
+ .correct_hw_break = kgdb_correct_hw_break,
+};
diff --git a/drivers/char/tty_io.c b/drivers/char/tty_io.c
index 613ec81..4d3c701 100644
--- a/drivers/char/tty_io.c
+++ b/drivers/char/tty_io.c
@@ -1155,6 +1155,48 @@ static struct tty_driver *get_tty_driver(dev_t device, int *index)
return NULL;
}
+#ifdef CONFIG_CONSOLE_POLL
+
+/**
+ * tty_find_polling_driver - find device of a polled tty
+ * @name: name string to match
+ * @line: pointer to resulting tty line nr
+ *
+ * This routine returns a tty driver structure, given a name
+ * and the condition that the tty driver is capable of polled
+ * operation.
+ */
+struct tty_driver *tty_find_polling_driver(char *name, int *line)
+{
+ struct tty_driver *p, *res = NULL;
+ int tty_line = 0;
+ char *str;
+
+ mutex_lock(&tty_mutex);
+ /* Search through the tty devices to look for a match */
+ list_for_each_entry(p, &tty_drivers, tty_drivers) {
+ str = name + strlen(p->name);
+ tty_line = simple_strtoul(str, &str, 10);
+ if (*str == ',')
+ str++;
+ if (*str == '\0')
+ str = 0;
+
+ if (tty_line >= 0 && tty_line <= p->num && p->poll_init &&
+ !p->poll_init(p, tty_line, str)) {
+
+ res = p;
+ *line = tty_line;
+ break;
+ }
+ }
+ mutex_unlock(&tty_mutex);
+
+ return res;
+}
+EXPORT_SYMBOL_GPL(tty_find_polling_driver);
+#endif
+
/**
* tty_check_change - check for POSIX terminal changes
* @tty: tty to check
@@ -3850,6 +3892,11 @@ void tty_set_operations(struct tty_driver *driver,
driver->write_proc = op->write_proc;
driver->tiocmget = op->tiocmget;
driver->tiocmset = op->tiocmset;
+#ifdef CONFIG_CONSOLE_POLL
+ driver->poll_init = op->poll_init;
+ driver->poll_get_char = op->poll_get_char;
+ driver->poll_put_char = op->poll_put_char;
+#endif
}
diff --git a/drivers/serial/8250.c b/drivers/serial/8250.c
index 77f7a7f..96a585e 100644
--- a/drivers/serial/8250.c
+++ b/drivers/serial/8250.c
@@ -1740,6 +1740,60 @@ static inline void wait_for_xmitr(struct uart_8250_port *up, int bits)
}
}
+#ifdef CONFIG_CONSOLE_POLL
+/*
+ * Console polling routines for writing and reading from the uart while
+ * in an interrupt or debug context.
+ */
+
+static int serial8250_get_poll_char(struct uart_port *port)
+{
+ struct uart_8250_port *up = (struct uart_8250_port *)port;
+ unsigned char lsr = serial_inp(up, UART_LSR);
+
+ while (!(lsr & UART_LSR_DR))
+ lsr = serial_inp(up, UART_LSR);
+
+ return serial_inp(up, UART_RX);
+}
+
+
+static void serial8250_put_poll_char(struct uart_port *port,
+ unsigned char c)
+{
+ unsigned int ier;
+ struct uart_8250_port *up = (struct uart_8250_port *)port;
+
+ /*
+ * First save the IER then disable the interrupts
+ */
+ ier = serial_in(up, UART_IER);
+ if (up->capabilities & UART_CAP_UUE)
+ serial_out(up, UART_IER, UART_IER_UUE);
+ else
+ serial_out(up, UART_IER, 0);
+
+ wait_for_xmitr(up, BOTH_EMPTY);
+ /*
+ * Send the character out.
+ * If a LF, also do CR...
+ */
+ serial_out(up, UART_TX, c);
+ if (c == 10) {
+ wait_for_xmitr(up, BOTH_EMPTY);
+ serial_out(up, UART_TX, 13);
+ }
+
+ /*
+ * Finally, wait for transmitter to become empty
+ * and restore the IER
+ */
+ wait_for_xmitr(up, BOTH_EMPTY);
+ serial_out(up, UART_IER, ier);
+}
+
+#endif /* CONFIG_CONSOLE_POLL */
+
static int serial8250_startup(struct uart_port *port)
{
struct uart_8250_port *up = (struct uart_8250_port *)port;
@@ -2386,6 +2440,10 @@ static struct uart_ops serial8250_pops = {
.request_port = serial8250_request_port,
.config_port = serial8250_config_port,
.verify_port = serial8250_verify_port,
+#ifdef CONFIG_CONSOLE_POLL
+ .poll_get_char = serial8250_get_poll_char,
+ .poll_put_char = serial8250_put_poll_char,
+#endif
};
static struct uart_8250_port serial8250_ports[UART_NR];
diff --git a/drivers/serial/Kconfig b/drivers/serial/Kconfig
index b82595c..5d9667c 100644
--- a/drivers/serial/Kconfig
+++ b/drivers/serial/Kconfig
@@ -961,6 +961,9 @@ config SERIAL_CORE
config SERIAL_CORE_CONSOLE
bool
+config CONSOLE_POLL
+ bool
+
config SERIAL_68328
bool "68328 serial support"
depends on M68328 || M68EZ328 || M68VZ328
diff --git a/drivers/serial/Makefile b/drivers/serial/Makefile
index 640cfe4..3cbea54 100644
--- a/drivers/serial/Makefile
+++ b/drivers/serial/Makefile
@@ -66,4 +66,5 @@ obj-$(CONFIG_SERIAL_UARTLITE) += uartlite.o
obj-$(CONFIG_SERIAL_NETX) += netx-serial.o
obj-$(CONFIG_SERIAL_OF_PLATFORM) += of_serial.o
obj-$(CONFIG_SERIAL_KS8695) += serial_ks8695.o
+obj-$(CONFIG_KGDB_SERIAL_CONSOLE) += kgdboc.o
obj-$(CONFIG_SERIAL_QE) += ucc_uart.o
diff --git a/drivers/serial/kgdboc.c b/drivers/serial/kgdboc.c
new file mode 100644
index 0000000..3418307
--- /dev/null
+++ b/drivers/serial/kgdboc.c
@@ -0,0 +1,163 @@
+/*
+ * Based on the same principle as kgdboe using the NETPOLL api, this
+ * driver uses a console polling api to implement a gdb serial inteface
+ * which is multiplexed on a console port.
+ *
+ * Maintainer: Jason Wessel <jason.wessel@windriver.com>
+ *
+ * 2007-2008 (c) Jason Wessel - Wind River Systems, Inc.
+ *
+ * This file is licensed under the terms of the GNU General Public
+ * License version 2. This program is licensed "as is" without any
+ * warranty of any kind, whether express or implied.
+ */
+#include <linux/kernel.h>
+#include <linux/ctype.h>
+#include <linux/kgdb.h>
+#include <linux/tty.h>
+
+#define MAX_CONFIG_LEN 40
+
+static struct kgdb_io kgdboc_io_ops;
+
+/* -1 = init not run yet, 0 = unconfigured, 1 = configured. */
+static int configured = -1;
+
+static char config[MAX_CONFIG_LEN];
+static struct kparam_string kps = {
+ .string = config,
+ .maxlen = MAX_CONFIG_LEN,
+};
+
+static struct tty_driver *kgdb_tty_driver;
+static int kgdb_tty_line;
+
+static int kgdboc_option_setup(char *opt)
+{
+ if (strlen(opt) > MAX_CONFIG_LEN) {
+ printk(KERN_ERR "kgdboc: config string too long\n");
+ return -ENOSPC;
+ }
+ strcpy(config, opt);
+
+ return 0;
+}
+
+__setup("kgdboc=", kgdboc_option_setup);
+
+static int configure_kgdboc(void)
+{
+ struct tty_driver *p;
+ int tty_line = 0;
+ int err;
+
+ err = kgdboc_option_setup(config);
+ if (err || !strlen(config) || isspace(config[0]))
+ goto noconfig;
+
+ err = -ENODEV;
+
+ p = tty_find_polling_driver(config, &tty_line);
+ if (!p)
+ goto noconfig;
+
+ kgdb_tty_driver = p;
+ kgdb_tty_line = tty_line;
+
+ err = kgdb_register_io_module(&kgdboc_io_ops);
+ if (err)
+ goto noconfig;
+
+ configured = 1;
+
+ return 0;
+
+noconfig:
+ config[0] = 0;
+ configured = 0;
+
+ return err;
+}
+
+static int __init init_kgdboc(void)
+{
+ /* Already configured? */
+ if (configured == 1)
+ return 0;
+
+ return configure_kgdboc();
+}
+
+static void cleanup_kgdboc(void)
+{
+ if (configured == 1)
+ kgdb_unregister_io_module(&kgdboc_io_ops);
+}
+
+static int kgdboc_get_char(void)
+{
+ return kgdb_tty_driver->poll_get_char(kgdb_tty_driver, kgdb_tty_line);
+}
+
+static void kgdboc_put_char(u8 chr)
+{
+ kgdb_tty_driver->poll_put_char(kgdb_tty_driver, kgdb_tty_line, chr);
+}
+
+static int param_set_kgdboc_var(const char *kmessage, struct kernel_param *kp)
+{
+ if (strlen(kmessage) >= MAX_CONFIG_LEN) {
+ printk(KERN_ERR "kgdboc: config string too long\n");
+ return -ENOSPC;
+ }
+
+ /* Only copy in the string if the init function has not run yet */
+ if (configured < 0) {
+ strcpy(config, kmessage);
+ return 0;
+ }
+
+ if (kgdb_connected) {
+ printk(KERN_ERR
+ "kgdboc: Cannot reconfigure while KGDB is connected.\n");
+
+ return -EBUSY;
+ }
+
+ strcpy(config, kmessage);
+
+ if (configured == 1)
+ cleanup_kgdboc();
+
+ /* Go and configure with the new params. */
+ return configure_kgdboc();
+}
+
+static void kgdboc_pre_exp_handler(void)
+{
+ /* Increment the module count when the debugger is active */
+ if (!kgdb_connected)
+ try_module_get(THIS_MODULE);
+}
+
+static void kgdboc_post_exp_handler(void)
+{
+ /* decrement the module count when the debugger detaches */
+ if (!kgdb_connected)
+ module_put(THIS_MODULE);
+}
+
+static struct kgdb_io kgdboc_io_ops = {
+ .name = "kgdboc",
+ .read_char = kgdboc_get_char,
+ .write_char = kgdboc_put_char,
+ .pre_exception = kgdboc_pre_exp_handler,
+ .post_exception = kgdboc_post_exp_handler,
+};
+
+module_init(init_kgdboc);
+module_exit(cleanup_kgdboc);
+module_param_call(kgdboc, param_set_kgdboc_var, param_get_string, &kps, 0644);
+MODULE_PARM_DESC(kgdboc, "<serial_device>[,baud]");
+MODULE_DESCRIPTION("KGDB Console TTY Driver");
+MODULE_LICENSE("GPL");
diff --git a/drivers/serial/serial_core.c b/drivers/serial/serial_core.c
index 0f5a179..cec193b 100644
--- a/drivers/serial/serial_core.c
+++ b/drivers/serial/serial_core.c
@@ -1827,7 +1827,7 @@ uart_get_console(struct uart_port *ports, int nr, struct console *co)
* options. The format of the string is <baud><parity><bits><flow>,
* eg: 115200n8r
*/
-void __init
+void
uart_parse_options(char *options, int *baud, int *parity, int *bits, int *flow)
{
char *s = options;
@@ -1872,7 +1872,7 @@ static const struct baud_rates baud_rates[] = {
* @bits: number of data bits
* @flow: flow control character - 'r' (rts)
*/
-int __init
+int
uart_set_options(struct uart_port *port, struct console *co,
int baud, int parity, int bits, int flow)
{
@@ -1924,7 +1924,12 @@ uart_set_options(struct uart_port *port, struct console *co,
port->mctrl |= TIOCM_DTR;
port->ops->set_termios(port, &termios, &dummy);
- co->cflag = termios.c_cflag;
+ /*
+ * Allow the setting of the UART parameters with a NULL console
+ * too:
+ */
+ if (co)
+ co->cflag = termios.c_cflag;
return 0;
}
@@ -2182,6 +2187,60 @@ uart_configure_port(struct uart_driver *drv, struct uart_state *state,
}
}
+#ifdef CONFIG_CONSOLE_POLL
+
+static int uart_poll_init(struct tty_driver *driver, int line, char *options)
+{
+ struct uart_driver *drv = driver->driver_state;
+ struct uart_state *state = drv->state + line;
+ struct uart_port *port;
+ int baud = 9600;
+ int bits = 8;
+ int parity = 'n';
+ int flow = 'n';
+
+ if (!state || !state->port)
+ return -1;
+
+ port = state->port;
+ if (!(port->ops->poll_get_char && port->ops->poll_put_char))
+ return -1;
+
+ if (options) {
+ uart_parse_options(options, &baud, &parity, &bits, &flow);
+ return uart_set_options(port, NULL, baud, parity, bits, flow);
+ }
+
+ return 0;
+}
+
+static int uart_poll_get_char(struct tty_driver *driver, int line)
+{
+ struct uart_driver *drv = driver->driver_state;
+ struct uart_state *state = drv->state + line;
+ struct uart_port *port;
+
+ if (!state || !state->port)
+ return -1;
+
+ port = state->port;
+ return port->ops->poll_get_char(port);
+}
+
+static void uart_poll_put_char(struct tty_driver *driver, int line, char ch)
+{
+ struct uart_driver *drv = driver->driver_state;
+ struct uart_state *state = drv->state + line;
+ struct uart_port *port;
+
+ if (!state || !state->port)
+ return;
+
+ port = state->port;
+ port->ops->poll_put_char(port, ch);
+}
+#endif
+
static const struct tty_operations uart_ops = {
.open = uart_open,
.close = uart_close,
@@ -2206,6 +2265,11 @@ static const struct tty_operations uart_ops = {
#endif
.tiocmget = uart_tiocmget,
.tiocmset = uart_tiocmset,
+#ifdef CONFIG_CONSOLE_POLL
+ .poll_init = uart_poll_init,
+ .poll_get_char = uart_poll_get_char,
+ .poll_put_char = uart_poll_put_char,
+#endif
};
/**
diff --git a/include/asm-x86/kgdb.h b/include/asm-x86/kgdb.h
new file mode 100644
index 0000000..484c475
--- /dev/null
+++ b/include/asm-x86/kgdb.h
@@ -0,0 +1,81 @@
+#ifndef _ASM_KGDB_H_
+#define _ASM_KGDB_H_
+
+/*
+ * Copyright (C) 2001-2004 Amit S. Kale
+ * Copyright (C) 2008 Wind River Systems, Inc.
+ */
+
+/*
+ * 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 1024
+
+/*
+ * 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.
+ */
+#ifdef CONFIG_X86_32
+enum regnames {
+ GDB_AX, /* 0 */
+ GDB_CX, /* 1 */
+ GDB_DX, /* 2 */
+ GDB_BX, /* 3 */
+ GDB_SP, /* 4 */
+ GDB_BP, /* 5 */
+ GDB_SI, /* 6 */
+ GDB_DI, /* 7 */
+ GDB_PC, /* 8 also known as eip */
+ GDB_PS, /* 9 also known as eflags */
+ GDB_CS, /* 10 */
+ GDB_SS, /* 11 */
+ GDB_DS, /* 12 */
+ GDB_ES, /* 13 */
+ GDB_FS, /* 14 */
+ GDB_GS, /* 15 */
+};
+#else /* ! CONFIG_X86_32 */
+enum regnames {
+ GDB_AX, /* 0 */
+ GDB_DX, /* 1 */
+ GDB_CX, /* 2 */
+ GDB_BX, /* 3 */
+ GDB_SI, /* 4 */
+ GDB_DI, /* 5 */
+ GDB_BP, /* 6 */
+ GDB_SP, /* 7 */
+ GDB_R8, /* 8 */
+ GDB_R9, /* 9 */
+ GDB_R10, /* 10 */
+ GDB_R11, /* 11 */
+ GDB_R12, /* 12 */
+ GDB_R13, /* 13 */
+ GDB_R14, /* 14 */
+ GDB_R15, /* 15 */
+ GDB_PC, /* 16 */
+ GDB_PS, /* 17 */
+};
+#endif /* CONFIG_X86_32 */
+
+/*
+ * Number of bytes of registers:
+ */
+#ifdef CONFIG_X86_32
+# define NUMREGBYTES 64
+#else
+# define NUMREGBYTES ((GDB_PS+1)*8)
+#endif
+
+static inline void arch_kgdb_breakpoint(void)
+{
+ asm(" int $3");
+}
+#define BREAK_INSTR_SIZE 1
+#define CACHE_FLUSH_IS_SAFE 1
+
+#endif /* _ASM_KGDB_H_ */
diff --git a/include/linux/kgdb.h b/include/linux/kgdb.h
new file mode 100644
index 0000000..b2be3a8
--- /dev/null
+++ b/include/linux/kgdb.h
@@ -0,0 +1,271 @@
+/*
+ * This provides the callbacks and functions that KGDB needs to share between
+ * the core, I/O and arch-specific portions.
+ *
+ * Author: Amit Kale <amitkale@linsyssoft.com> and
+ * Tom Rini <trini@kernel.crashing.org>
+ *
+ * 2001-2004 (c) Amit S. Kale and 2003-2005 (c) MontaVista Software, Inc.
+ * This file is licensed under the terms of the GNU General Public License
+ * version 2. This program is licensed "as is" without any warranty of any
+ * kind, whether express or implied.
+ */
+#ifndef _KGDB_H_
+#define _KGDB_H_
+
+#include <linux/serial_8250.h>
+#include <linux/linkage.h>
+#include <linux/init.h>
+
+#include <asm/atomic.h>
+#include <asm/kgdb.h>
+
+struct pt_regs;
+
+/*
+ * kgdb_skipexception - Bail of of KGDB when we've been triggered.
+ * @exception: Exception vector number
+ * @regs: Current &struct pt_regs.
+ *
+ * On some architectures we need to skip a breakpoint exception when
+ * it occurs after a breakpoint has been removed.
+ */
+extern int kgdb_skipexception(int exception, struct pt_regs *regs);
+
+/*
+ * kgdb_post_primary_code - Save error vector/code numbers.
+ * @regs: Original pt_regs.
+ * @e_vector: Original error vector.
+ * @err_code: Original error code.
+ *
+ * This is needed on architectures which support SMP and KGDB.
+ * This function is called after all the secondary cpus have been put
+ * to a know spin state and the primary CPU has control over KGDB.
+ */
+extern void kgdb_post_primary_code(struct pt_regs *regs, int e_vector,
+ int err_code);
+
+/*
+ * kgdb_disable_hw_debug - Disable hardware debugging while we in kgdb.
+ * @regs: Current &struct pt_regs.
+ *
+ * This function will be called if the particular architecture must
+ * disable hardware debugging while it is processing gdb packets or
+ * handling exception.
+ */
+extern void kgdb_disable_hw_debug(struct pt_regs *regs);
+
+struct tasklet_struct;
+struct task_struct;
+struct uart_port;
+
+/* To enter the debugger explicitly. */
+void kgdb_breakpoint(void);
+
+extern int kgdb_connected;
+
+extern atomic_t kgdb_setting_breakpoint;
+extern atomic_t kgdb_cpu_doing_single_step;
+
+extern struct task_struct *kgdb_usethread;
+extern struct task_struct *kgdb_contthread;
+
+enum kgdb_bptype {
+ BP_BREAKPOINT = 0,
+ BP_HARDWARE_BREAKPOINT,
+ BP_WRITE_WATCHPOINT,
+ BP_READ_WATCHPOINT,
+ BP_ACCESS_WATCHPOINT
+};
+
+enum kgdb_bpstate {
+ BP_UNDEFINED = 0,
+ BP_REMOVED,
+ BP_SET,
+ BP_ACTIVE
+};
+
+struct kgdb_bkpt {
+ unsigned long bpt_addr;
+ unsigned char saved_instr[BREAK_INSTR_SIZE];
+ enum kgdb_bptype type;
+ enum kgdb_bpstate state;
+};
+
+#ifndef KGDB_MAX_BREAKPOINTS
+# define KGDB_MAX_BREAKPOINTS 1000
+#endif
+
+#define KGDB_HW_BREAKPOINT 1
+
+/*
+ * Functions each KGDB-supporting architecture must provide:
+ */
+
+/*
+ * kgdb_arch_init - Perform any architecture specific initalization.
+ *
+ * This function will handle the initalization of any architecture
+ * specific callbacks.
+ */
+extern int kgdb_arch_init(void);
+
+/*
+ * kgdb_arch_exit - Perform any architecture specific uninitalization.
+ *
+ * This function will handle the uninitalization of any architecture
+ * specific callbacks, for dynamic registration and unregistration.
+ */
+extern void kgdb_arch_exit(void);
+
+/*
+ * pt_regs_to_gdb_regs - Convert ptrace regs to GDB regs
+ * @gdb_regs: A pointer to hold the registers in the order GDB wants.
+ * @regs: The &struct pt_regs of the current process.
+ *
+ * Convert the pt_regs in @regs into the format for registers that
+ * GDB expects, stored in @gdb_regs.
+ */
+extern void pt_regs_to_gdb_regs(unsigned long *gdb_regs, struct pt_regs *regs);
+
+/*
+ * sleeping_thread_to_gdb_regs - Convert ptrace regs to GDB regs
+ * @gdb_regs: A pointer to hold the registers in the order GDB wants.
+ * @p: The &struct task_struct of the desired process.
+ *
+ * Convert the register values of the sleeping process in @p to
+ * the format that GDB expects.
+ * This function is called when kgdb does not have access to the
+ * &struct pt_regs and therefore it should fill the gdb registers
+ * @gdb_regs with what has been saved in &struct thread_struct
+ * thread field during switch_to.
+ */
+extern void
+sleeping_thread_to_gdb_regs(unsigned long *gdb_regs, struct task_struct *p);
+
+/*
+ * gdb_regs_to_pt_regs - Convert GDB regs to ptrace regs.
+ * @gdb_regs: A pointer to hold the registers we've received from GDB.
+ * @regs: A pointer to a &struct pt_regs to hold these values in.
+ *
+ * Convert the GDB regs in @gdb_regs into the pt_regs, and store them
+ * in @regs.
+ */
+extern void gdb_regs_to_pt_regs(unsigned long *gdb_regs, struct pt_regs *regs);
+
+/*
+ * kgdb_arch_handle_exception - Handle architecture specific GDB packets.
+ * @vector: The error vector of the exception that happened.
+ * @signo: The signal number of the exception that happened.
+ * @err_code: The error code of the exception that happened.
+ * @remcom_in_buffer: The buffer of the packet we have read.
+ * @remcom_out_buffer: The buffer of %BUFMAX bytes to write a packet into.
+ * @regs: The &struct pt_regs of the current process.
+ *
+ * This function MUST handle the 'c' and 's' command packets,
+ * as well packets to set / remove a hardware breakpoint, if used.
+ * If there are additional packets which the hardware needs to handle,
+ * they are handled here. The code should return -1 if it wants to
+ * process more packets, and a %0 or %1 if it wants to exit from the
+ * kgdb callback.
+ */
+extern int
+kgdb_arch_handle_exception(int vector, int signo, int err_code,
+ char *remcom_in_buffer,
+ char *remcom_out_buffer,
+ struct pt_regs *regs);
+
+/*
+ * kgdb_roundup_cpus - Get other CPUs into a holding pattern
+ * @flags: Current IRQ state
+ *
+ * On SMP systems, we need to get the attention of the other CPUs
+ * and get them be in a known state. This should do what is needed
+ * to get the other CPUs to call kgdb_wait(). Note that on some arches,
+ * the NMI approach is not used for rounding up all the CPUs. For example,
+ * in case of MIPS, smp_call_function() is used to roundup CPUs. In
+ * this case, we have to make sure that interrupts are enabled before
+ * calling smp_call_function(). The argument to this function is
+ * the flags that will be used when restoring the interrupts. There is
+ * local_irq_save() call before kgdb_roundup_cpus().
+ *
+ * On non-SMP systems, this is not called.
+ */
+extern void kgdb_roundup_cpus(unsigned long flags);
+
+/* Optional functions. */
+extern int kgdb_validate_break_address(unsigned long addr);
+extern int kgdb_arch_set_breakpoint(unsigned long addr, char *saved_instr);
+extern int kgdb_arch_remove_breakpoint(unsigned long addr, char *bundle);
+
+/*
+ * struct kgdb_arch - Describe architecture specific values.
+ * @gdb_bpt_instr: The instruction to trigger a breakpoint.
+ * @flags: Flags for the breakpoint, currently just %KGDB_HW_BREAKPOINT.
+ * @set_breakpoint: Allow an architecture to specify how to set a software
+ * breakpoint.
+ * @remove_breakpoint: Allow an architecture to specify how to remove a
+ * software breakpoint.
+ * @set_hw_breakpoint: Allow an architecture to specify how to set a hardware
+ * breakpoint.
+ * @remove_hw_breakpoint: Allow an architecture to specify how to remove a
+ * hardware breakpoint.
+ * @remove_all_hw_break: Allow an architecture to specify how to remove all
+ * hardware breakpoints.
+ * @correct_hw_break: Allow an architecture to specify how to correct the
+ * hardware debug registers.
+ */
+struct kgdb_arch {
+ unsigned char gdb_bpt_instr[BREAK_INSTR_SIZE];
+ unsigned long flags;
+
+ int (*set_breakpoint)(unsigned long, char *);
+ int (*remove_breakpoint)(unsigned long, char *);
+ int (*set_hw_breakpoint)(unsigned long, int, enum kgdb_bptype);
+ int (*remove_hw_breakpoint)(unsigned long, int, enum kgdb_bptype);
+ void (*remove_all_hw_break)(void);
+ void (*correct_hw_break)(void);
+};
+
+/*
+ * struct kgdb_io - Describe the interface for an I/O driver to talk with KGDB.
+ * @name: Name of the I/O driver.
+ * @read_char: Pointer to a function that will return one char.
+ * @write_char: Pointer to a function that will write one char.
+ * @flush: Pointer to a function that will flush any pending writes.
+ * @init: Pointer to a function that will initialize the device.
+ * @pre_exception: Pointer to a function that will do any prep work for
+ * the I/O driver.
+ * @post_exception: Pointer to a function that will do any cleanup work
+ * for the I/O driver.
+ */
+struct kgdb_io {
+ const char *name;
+ int (*read_char) (void);
+ void (*write_char) (u8);
+ void (*flush) (void);
+ int (*init) (void);
+ void (*pre_exception) (void);
+ void (*post_exception) (void);
+};
+
+extern struct kgdb_arch arch_kgdb_ops;
+
+extern int kgdb_register_io_module(struct kgdb_io *local_kgdb_io_ops);
+extern void kgdb_unregister_io_module(struct kgdb_io *local_kgdb_io_ops);
+
+extern int kgdb_hex2long(char **ptr, long *long_val);
+extern int kgdb_mem2hex(char *mem, char *buf, int count);
+extern int kgdb_hex2mem(char *buf, char *mem, int count);
+
+extern int kgdb_isremovedbreak(unsigned long addr);
+
+extern int
+kgdb_handle_exception(int ex_vector, int signo, int err_code,
+ struct pt_regs *regs);
+extern int kgdb_nmicallback(int cpu, void *regs);
+
+extern int kgdb_single_step;
+extern atomic_t kgdb_active;
+
+#endif /* _KGDB_H_ */
diff --git a/include/linux/pid.h b/include/linux/pid.h
index f84d532..e066d3d 100644
--- a/include/linux/pid.h
+++ b/include/linux/pid.h
@@ -86,6 +86,8 @@ extern struct task_struct *FASTCALL(get_pid_task(struct pid *pid,
extern struct pid *get_task_pid(struct task_struct *task, enum pid_type type);
+extern int pid_max;
+
/*
* attach_pid() and detach_pid() must be called with the tasklist_lock
* write-held.
diff --git a/include/linux/serial_core.h b/include/linux/serial_core.h
index 1a0b6cf..7d1a46b 100644
--- a/include/linux/serial_core.h
+++ b/include/linux/serial_core.h
@@ -211,6 +211,10 @@ struct uart_ops {
void (*config_port)(struct uart_port *, int);
int (*verify_port)(struct uart_port *, struct serial_struct *);
int (*ioctl)(struct uart_port *, unsigned int, unsigned long);
+#ifdef CONFIG_CONSOLE_POLL
+ void (*poll_put_char)(struct uart_port *, unsigned char);
+ int (*poll_get_char)(struct uart_port *);
+#endif
};
#define UART_CONFIG_TYPE (1 << 0)
diff --git a/include/linux/tty_driver.h b/include/linux/tty_driver.h
index 85c95cd..21f69ac 100644
--- a/include/linux/tty_driver.h
+++ b/include/linux/tty_driver.h
@@ -125,6 +125,7 @@
#include <linux/cdev.h>
struct tty_struct;
+struct tty_driver;
struct tty_operations {
int (*open)(struct tty_struct * tty, struct file * filp);
@@ -157,6 +158,11 @@ struct tty_operations {
int (*tiocmget)(struct tty_struct *tty, struct file *file);
int (*tiocmset)(struct tty_struct *tty, struct file *file,
unsigned int set, unsigned int clear);
+#ifdef CONFIG_CONSOLE_POLL
+ int (*poll_init)(struct tty_driver *driver, int line, char *options);
+ int (*poll_get_char)(struct tty_driver *driver, int line);
+ void (*poll_put_char)(struct tty_driver *driver, int line, char ch);
+#endif
};
struct tty_driver {
@@ -220,6 +226,11 @@ struct tty_driver {
int (*tiocmget)(struct tty_struct *tty, struct file *file);
int (*tiocmset)(struct tty_struct *tty, struct file *file,
unsigned int set, unsigned int clear);
+#ifdef CONFIG_CONSOLE_POLL
+ int (*poll_init)(struct tty_driver *driver, int line, char *options);
+ int (*poll_get_char)(struct tty_driver *driver, int line);
+ void (*poll_put_char)(struct tty_driver *driver, int line, char ch);
+#endif
struct list_head tty_drivers;
};
@@ -230,6 +241,7 @@ struct tty_driver *alloc_tty_driver(int lines);
void put_tty_driver(struct tty_driver *driver);
void tty_set_operations(struct tty_driver *driver,
const struct tty_operations *op);
+extern struct tty_driver *tty_find_polling_driver(char *name, int *line);
/* tty driver magic number */
#define TTY_DRIVER_MAGIC 0x5402
diff --git a/include/linux/uaccess.h b/include/linux/uaccess.h
index 975c963..fec6dec 100644
--- a/include/linux/uaccess.h
+++ b/include/linux/uaccess.h
@@ -84,4 +84,26 @@ static inline unsigned long __copy_from_user_nocache(void *to,
ret; \
})
+/*
+ * probe_kernel_read(): safely attempt to read from a location
+ * @dst: pointer to the buffer that shall take the data
+ * @src: address to read from
+ * @size: size of the data chunk
+ *
+ * Safely read from address @src to the buffer at @dst. If a kernel fault
+ * happens, handle that and return -EFAULT.
+ */
+extern long probe_kernel_read(void *dst, void *src, size_t size);
+
+/*
+ * probe_kernel_write(): safely attempt to write to a location
+ * @dst: address to write to
+ * @src: pointer to the data that shall be written
+ * @size: size of the data chunk
+ *
+ * Safely write to address @dst from the buffer at @src. If a kernel fault
+ * happens, handle that and return -EFAULT.
+ */
+extern long probe_kernel_write(void *dst, void *src, size_t size);
+
#endif /* __LINUX_UACCESS_H__ */
diff --git a/kernel/Makefile b/kernel/Makefile
index 6c584c5..05c8003 100644
--- a/kernel/Makefile
+++ b/kernel/Makefile
@@ -53,6 +53,7 @@ obj-$(CONFIG_AUDIT) += audit.o auditfilter.o
obj-$(CONFIG_AUDITSYSCALL) += auditsc.o
obj-$(CONFIG_AUDIT_TREE) += audit_tree.o
obj-$(CONFIG_KPROBES) += kprobes.o
+obj-$(CONFIG_KGDB) += kgdb.o
obj-$(CONFIG_DETECT_SOFTLOCKUP) += softlockup.o
obj-$(CONFIG_GENERIC_HARDIRQS) += irq/
obj-$(CONFIG_SECCOMP) += seccomp.o
diff --git a/kernel/kgdb.c b/kernel/kgdb.c
new file mode 100644
index 0000000..2bfdd48
--- /dev/null
+++ b/kernel/kgdb.c
@@ -0,0 +1,1663 @@
+/*
+ * KGDB stub.
+ *
+ * Maintainer: Jason Wessel <jason.wessel@windriver.com>
+ *
+ * Copyright (C) 2000-2001 VERITAS Software Corporation.
+ * Copyright (C) 2002-2004 Timesys Corporation
+ * Copyright (C) 2003-2004 Amit S. Kale <amitkale@linsyssoft.com>
+ * Copyright (C) 2004 Pavel Machek <pavel@suse.cz>
+ * Copyright (C) 2004-2006 Tom Rini <trini@kernel.crashing.org>
+ * Copyright (C) 2004-2006 LinSysSoft Technologies Pvt. Ltd.
+ * Copyright (C) 2005-2008 Wind River Systems, Inc.
+ * Copyright (C) 2007 MontaVista Software, Inc.
+ * Copyright (C) 2008 Red Hat, Inc., Ingo Molnar <mingo@redhat.com>
+ *
+ * Contributors at various stages not listed above:
+ * Jason Wessel ( jason.wessel@windriver.com )
+ * George Anzinger <george@mvista.com>
+ * Anurekh Saxena (anurekh.saxena@timesys.com)
+ * Lake Stevens Instrument Division (Glenn Engel)
+ * Jim Kingdon, Cygnus Support.
+ *
+ * Original KGDB stub: David Grothe <dave@gcom.com>,
+ * Tigran Aivazian <tigran@sco.com>
+ *
+ * This file is licensed under the terms of the GNU General Public License
+ * version 2. This program is licensed "as is" without any warranty of any
+ * kind, whether express or implied.
+ */
+#include <linux/pid_namespace.h>
+#include <linux/interrupt.h>
+#include <linux/spinlock.h>
+#include <linux/console.h>
+#include <linux/threads.h>
+#include <linux/uaccess.h>
+#include <linux/kernel.h>
+#include <linux/module.h>
+#include <linux/ptrace.h>
+#include <linux/reboot.h>
+#include <linux/string.h>
+#include <linux/delay.h>
+#include <linux/sched.h>
+#include <linux/sysrq.h>
+#include <linux/init.h>
+#include <linux/kgdb.h>
+#include <linux/pid.h>
+#include <linux/smp.h>
+#include <linux/mm.h>
+
+#include <asm/cacheflush.h>
+#include <asm/byteorder.h>
+#include <asm/atomic.h>
+#include <asm/system.h>
+
+static int kgdb_break_asap;
+
+struct kgdb_state {
+ int ex_vector;
+ int signo;
+ int err_code;
+ int cpu;
+ int pass_exception;
+ long threadid;
+ long kgdb_usethreadid;
+ struct pt_regs *linux_regs;
+};
+
+static struct debuggerinfo_struct {
+ void *debuggerinfo;
+ struct task_struct *task;
+} kgdb_info[NR_CPUS];
+
+/**
+ * kgdb_connected - Is a host GDB connected to us?
+ */
+int kgdb_connected;
+EXPORT_SYMBOL_GPL(kgdb_connected);
+
+/* All the KGDB handlers are installed */
+static int kgdb_io_module_registered;
+
+/* Guard for recursive entry */
+static int exception_level;
+
+static struct kgdb_io *kgdb_io_ops;
+static DEFINE_SPINLOCK(kgdb_registration_lock);
+
+/* kgdb console driver is loaded */
+static int kgdb_con_registered;
+/* determine if kgdb console output should be used */
+static int kgdb_use_con;
+
+static int __init opt_kgdb_con(char *str)
+{
+ kgdb_use_con = 1;
+ return 0;
+}
+
+early_param("kgdbcon", opt_kgdb_con);
+
+module_param(kgdb_use_con, int, 0644);
+
+/*
+ * Holds information about breakpoints in a kernel. These breakpoints are
+ * added and removed by gdb.
+ */
+static struct kgdb_bkpt kgdb_break[KGDB_MAX_BREAKPOINTS] = {
+ [0 ... KGDB_MAX_BREAKPOINTS-1] = { .state = BP_UNDEFINED }
+};
+
+/*
+ * The CPU# of the active CPU, or -1 if none:
+ */
+atomic_t kgdb_active = ATOMIC_INIT(-1);
+
+/*
+ * We use NR_CPUs not PERCPU, in case kgdb is used to debug early
+ * bootup code (which might not have percpu set up yet):
+ */
+static atomic_t passive_cpu_wait[NR_CPUS];
+static atomic_t cpu_in_kgdb[NR_CPUS];
+atomic_t kgdb_setting_breakpoint;
+
+struct task_struct *kgdb_usethread;
+struct task_struct *kgdb_contthread;
+
+int kgdb_single_step;
+
+/* Our I/O buffers. */
+static char remcom_in_buffer[BUFMAX];
+static char remcom_out_buffer[BUFMAX];
+
+/* Storage for the registers, in GDB format. */
+static unsigned long gdb_regs[(NUMREGBYTES +
+ sizeof(unsigned long) - 1) /
+ sizeof(unsigned long)];
+
+/* to keep track of the CPU which is doing the single stepping*/
+atomic_t kgdb_cpu_doing_single_step = ATOMIC_INIT(-1);
+
+/*
+ * Finally, some KGDB code :-)
+ */
+
+/*
+ * Weak aliases for breakpoint management,
+ * can be overriden by architectures when needed:
+ */
+int __weak kgdb_validate_break_address(unsigned long addr)
+{
+ char tmp_variable[BREAK_INSTR_SIZE];
+
+ return probe_kernel_read(tmp_variable, (char *)addr, BREAK_INSTR_SIZE);
+}
+
+int __weak kgdb_arch_set_breakpoint(unsigned long addr, char *saved_instr)
+{
+ int err;
+
+ err = probe_kernel_read(saved_instr, (char *)addr, BREAK_INSTR_SIZE);
+ if (err)
+ return err;
+
+ return probe_kernel_write((char *)addr, arch_kgdb_ops.gdb_bpt_instr,
+ BREAK_INSTR_SIZE);
+}
+
+int __weak kgdb_arch_remove_breakpoint(unsigned long addr, char *bundle)
+{
+ return probe_kernel_write((char *)addr,
+ (char *)bundle, BREAK_INSTR_SIZE);
+}
+
+unsigned long __weak kgdb_arch_pc(int exception, struct pt_regs *regs)
+{
+ return instruction_pointer(regs);
+}
+
+int __weak kgdb_arch_init(void)
+{
+ return 0;
+}
+
+/*
+ * GDB remote protocol parser:
+ */
+
+static const char hexchars[] = "0123456789abcdef";
+
+static 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 $<data>#<checksum> */
+static void get_packet(char *buffer)
+{
+ unsigned char checksum;
+ unsigned char xmitcsum;
+ int count;
+ char ch;
+
+ do {
+ /*
+ * Spin and wait around for the start character, ignore all
+ * other characters:
+ */
+ while ((ch = (kgdb_io_ops->read_char())) != '$')
+ /* nothing */;
+
+ kgdb_connected = 1;
+ checksum = 0;
+ xmitcsum = -1;
+
+ count = 0;
+
+ /*
+ * now, read until a # or end of buffer is found:
+ */
+ while (count < (BUFMAX - 1)) {
+ ch = kgdb_io_ops->read_char();
+ if (ch == '#')
+ break;
+ checksum = checksum + ch;
+ buffer[count] = ch;
+ count = count + 1;
+ }
+ buffer[count] = 0;
+
+ if (ch == '#') {
+ xmitcsum = hex(kgdb_io_ops->read_char()) << 4;
+ xmitcsum += hex(kgdb_io_ops->read_char());
+
+ if (checksum != xmitcsum)
+ /* failed checksum */
+ kgdb_io_ops->write_char('-');
+ else
+ /* successful transfer */
+ kgdb_io_ops->write_char('+');
+ if (kgdb_io_ops->flush)
+ kgdb_io_ops->flush();
+ }
+ } while (checksum != xmitcsum);
+}
+
+/*
+ * Send the packet in buffer.
+ * Check for gdb connection if asked for.
+ */
+static void put_packet(char *buffer)
+{
+ unsigned char checksum;
+ int count;
+ char ch;
+
+ /*
+ * $<packet info>#<checksum>.
+ */
+ while (1) {
+ kgdb_io_ops->write_char('$');
+ checksum = 0;
+ count = 0;
+
+ while ((ch = buffer[count])) {
+ kgdb_io_ops->write_char(ch);
+ checksum += ch;
+ count++;
+ }
+
+ kgdb_io_ops->write_char('#');
+ kgdb_io_ops->write_char(hexchars[checksum >> 4]);
+ kgdb_io_ops->write_char(hexchars[checksum & 0xf]);
+ if (kgdb_io_ops->flush)
+ kgdb_io_ops->flush();
+
+ /* Now see what we get in reply. */
+ ch = kgdb_io_ops->read_char();
+
+ if (ch == 3)
+ ch = kgdb_io_ops->read_char();
+
+ /* If we get an ACK, we are done. */
+ if (ch == '+')
+ return;
+
+ /*
+ * If we get the start of another packet, this means
+ * that GDB is attempting to reconnect. We will NAK
+ * the packet being sent, and stop trying to send this
+ * packet.
+ */
+ if (ch == '$') {
+ kgdb_io_ops->write_char('-');
+ if (kgdb_io_ops->flush)
+ kgdb_io_ops->flush();
+ return;
+ }
+ }
+}
+
+static char *pack_hex_byte(char *pkt, u8 byte)
+{
+ *pkt++ = hexchars[byte >> 4];
+ *pkt++ = hexchars[byte & 0xf];
+
+ return pkt;
+}
+
+/*
+ * Convert the memory pointed to by mem into hex, placing result in buf.
+ * Return a pointer to the last char put in buf (null). May return an error.
+ */
+int kgdb_mem2hex(char *mem, char *buf, int count)
+{
+ char *tmp;
+ int err;
+
+ /*
+ * We use the upper half of buf as an intermediate buffer for the
+ * raw memory copy. Hex conversion will work against this one.
+ */
+ tmp = buf + count;
+
+ err = probe_kernel_read(tmp, mem, count);
+ if (!err) {
+ while (count > 0) {
+ buf = pack_hex_byte(buf, *tmp);
+ tmp++;
+ count--;
+ }
+
+ *buf = 0;
+ }
+
+ return err;
+}
+
+/*
+ * Copy the binary array pointed to by buf into mem. Fix $, #, and
+ * 0x7d escaped with 0x7d. Return a pointer to the character after
+ * the last byte written.
+ */
+static int kgdb_ebin2mem(char *buf, char *mem, int count)
+{
+ int err = 0;
+ char c;
+
+ while (count-- > 0) {
+ c = *buf++;
+ if (c == 0x7d)
+ c = *buf++ ^ 0x20;
+
+ err = probe_kernel_write(mem, &c, 1);
+ if (err)
+ break;
+
+ mem++;
+ }
+
+ return err;
+}
+
+/*
+ * 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.
+ * May return an error.
+ */
+int kgdb_hex2mem(char *buf, char *mem, int count)
+{
+ char *tmp_raw;
+ char *tmp_hex;
+
+ /*
+ * We use the upper half of buf as an intermediate buffer for the
+ * raw memory that is converted from hex.
+ */
+ tmp_raw = buf + count * 2;
+
+ tmp_hex = tmp_raw - 1;
+ while (tmp_hex >= buf) {
+ tmp_raw--;
+ *tmp_raw = hex(*tmp_hex--);
+ *tmp_raw |= hex(*tmp_hex--) << 4;
+ }
+
+ return probe_kernel_write(mem, tmp_raw, count);
+}
+
+/*
+ * While we find nice hex chars, build a long_val.
+ * Return number of chars processed.
+ */
+int kgdb_hex2long(char **ptr, long *long_val)
+{
+ int hex_val;
+ int num = 0;
+
+ *long_val = 0;
+
+ while (**ptr) {
+ hex_val = hex(**ptr);
+ if (hex_val < 0)
+ break;
+
+ *long_val = (*long_val << 4) | hex_val;
+ num++;
+ (*ptr)++;
+ }
+
+ return num;
+}
+
+/* Write memory due to an 'M' or 'X' packet. */
+static int write_mem_msg(int binary)
+{
+ char *ptr = &remcom_in_buffer[1];
+ unsigned long addr;
+ unsigned long length;
+ int err;
+
+ if (kgdb_hex2long(&ptr, &addr) > 0 && *(ptr++) == ',' &&
+ kgdb_hex2long(&ptr, &length) > 0 && *(ptr++) == ':') {
+ if (binary)
+ err = kgdb_ebin2mem(ptr, (char *)addr, length);
+ else
+ err = kgdb_hex2mem(ptr, (char *)addr, length);
+ if (err)
+ return err;
+ if (CACHE_FLUSH_IS_SAFE)
+ flush_icache_range(addr, addr + length + 1);
+ return 0;
+ }
+
+ return -EINVAL;
+}
+
+static void error_packet(char *pkt, int error)
+{
+ error = -error;
+ pkt[0] = 'E';
+ pkt[1] = hexchars[(error / 10)];
+ pkt[2] = hexchars[(error % 10)];
+ pkt[3] = '\0';
+}
+
+/*
+ * Black magic portion #2. Thread ID accessors.
+ */
+
+#define BUF_THREAD_ID_SIZE 16
+
+static char *pack_threadid(char *pkt, unsigned char *id)
+{
+ char *limit;
+
+ limit = pkt + BUF_THREAD_ID_SIZE;
+ while (pkt < limit)
+ pkt = pack_hex_byte(pkt, *id++);
+
+ return pkt;
+}
+
+static void int_to_threadref(unsigned char *id, int value)
+{
+ unsigned char *scan;
+ int i = 4;
+
+ scan = (unsigned char *)id;
+ while (i--)
+ *scan++ = 0;
+ *scan++ = (value >> 24) & 0xff;
+ *scan++ = (value >> 16) & 0xff;
+ *scan++ = (value >> 8) & 0xff;
+ *scan++ = (value & 0xff);
+}
+
+static struct task_struct *getthread(struct pt_regs *regs, int tid)
+{
+ if (num_online_cpus() && (tid >= pid_max + num_online_cpus()))
+ return NULL;
+
+ if (tid >= pid_max)
+ return idle_task(tid - pid_max);
+
+ if (!tid)
+ return NULL;
+
+ /*
+ * find_task_by_pid() does not take the tasklist lock anymore
+ * but is nicely RCU locked - hence is a pretty resilient
+ * thing to use:
+ */
+ return find_task_by_pid(tid);
+}
+
+/*
+ * CPU debug state control:
+ */
+
+#ifdef CONFIG_SMP
+static void kgdb_wait(struct pt_regs *regs)
+{
+ unsigned long flags;
+ int cpu;
+
+ local_irq_save(flags);
+ cpu = raw_smp_processor_id();
+ kgdb_info[cpu].debuggerinfo = regs;
+ kgdb_info[cpu].task = current;
+ /*
+ * Make sure the above info reaches the primary CPU before
+ * our cpu_in_kgdb[] flag setting does:
+ */
+ smp_wmb();
+ atomic_set(&cpu_in_kgdb[cpu], 1);
+
+ /*
+ * The primary CPU must be active to enter here, but this is
+ * guard in case the primary CPU had not been selected if
+ * this was an entry via nmi.
+ */
+ while (atomic_read(&kgdb_active) == -1)
+ cpu_relax();
+
+ /* Wait till primary CPU goes completely into the debugger. */
+ while (!atomic_read(&cpu_in_kgdb[atomic_read(&kgdb_active)]))
+ cpu_relax();
+
+ /* Wait till primary CPU is done with debugging */
+ while (atomic_read(&passive_cpu_wait[cpu]))
+ cpu_relax();
+
+ kgdb_info[cpu].debuggerinfo = NULL;
+ kgdb_info[cpu].task = NULL;
+
+ /* fix up hardware debug registers on local cpu */
+ if (arch_kgdb_ops.correct_hw_break)
+ arch_kgdb_ops.correct_hw_break();
+
+ /* Signal the primary CPU that we are done: */
+ atomic_set(&cpu_in_kgdb[cpu], 0);
+ local_irq_restore(flags);
+}
+#endif
+
+/*
+ * Some architectures need cache flushes when we set/clear a
+ * breakpoint:
+ */
+static void kgdb_flush_swbreak_addr(unsigned long addr)
+{
+ if (!CACHE_FLUSH_IS_SAFE)
+ return;
+
+ if (current->mm) {
+ flush_cache_range(current->mm->mmap_cache,
+ addr, addr + BREAK_INSTR_SIZE);
+ } else {
+ flush_icache_range(addr, addr + BREAK_INSTR_SIZE);
+ }
+}
+
+/*
+ * SW breakpoint management:
+ */
+static int kgdb_activate_sw_breakpoints(void)
+{
+ unsigned long addr;
+ int error = 0;
+ int i;
+
+ for (i = 0; i < KGDB_MAX_BREAKPOINTS; i++) {
+ if (kgdb_break[i].state != BP_SET)
+ continue;
+
+ addr = kgdb_break[i].bpt_addr;
+ error = kgdb_arch_set_breakpoint(addr,
+ kgdb_break[i].saved_instr);
+ if (error)
+ return error;
+
+ kgdb_flush_swbreak_addr(addr);
+ kgdb_break[i].state = BP_ACTIVE;
+ }
+ return 0;
+}
+
+static int kgdb_set_sw_break(unsigned long addr)
+{
+ int err = kgdb_validate_break_address(addr);
+ int breakno = -1;
+ int i;
+
+ if (err)
+ return err;
+
+ for (i = 0; i < KGDB_MAX_BREAKPOINTS; i++) {
+ if ((kgdb_break[i].state == BP_SET) &&
+ (kgdb_break[i].bpt_addr == addr))
+ return -EEXIST;
+ }
+ for (i = 0; i < KGDB_MAX_BREAKPOINTS; i++) {
+ if (kgdb_break[i].state == BP_REMOVED &&
+ kgdb_break[i].bpt_addr == addr) {
+ breakno = i;
+ break;
+ }
+ }
+
+ if (breakno == -1) {
+ for (i = 0; i < KGDB_MAX_BREAKPOINTS; i++) {
+ if (kgdb_break[i].state == BP_UNDEFINED) {
+ breakno = i;
+ break;
+ }
+ }
+ }
+
+ if (breakno == -1)
+ return -E2BIG;
+
+ kgdb_break[breakno].state = BP_SET;
+ kgdb_break[breakno].type = BP_BREAKPOINT;
+ kgdb_break[breakno].bpt_addr = addr;
+
+ return 0;
+}
+
+static int kgdb_deactivate_sw_breakpoints(void)
+{
+ unsigned long addr;
+ int error = 0;
+ int i;
+
+ for (i = 0; i < KGDB_MAX_BREAKPOINTS; i++) {
+ if (kgdb_break[i].state != BP_ACTIVE)
+ continue;
+ addr = kgdb_break[i].bpt_addr;
+ error = kgdb_arch_remove_breakpoint(addr,
+ kgdb_break[i].saved_instr);
+ if (error)
+ return error;
+
+ kgdb_flush_swbreak_addr(addr);
+ kgdb_break[i].state = BP_SET;
+ }
+ return 0;
+}
+
+static int kgdb_remove_sw_break(unsigned long addr)
+{
+ int i;
+
+ for (i = 0; i < KGDB_MAX_BREAKPOINTS; i++) {
+ if ((kgdb_break[i].state == BP_SET) &&
+ (kgdb_break[i].bpt_addr == addr)) {
+ kgdb_break[i].state = BP_REMOVED;
+ return 0;
+ }
+ }
+ return -ENOENT;
+}
+
+int kgdb_isremovedbreak(unsigned long addr)
+{
+ int i;
+
+ for (i = 0; i < KGDB_MAX_BREAKPOINTS; i++) {
+ if ((kgdb_break[i].state == BP_REMOVED) &&
+ (kgdb_break[i].bpt_addr == addr))
+ return 1;
+ }
+ return 0;
+}
+
+int remove_all_break(void)
+{
+ unsigned long addr;
+ int error;
+ int i;
+
+ /* Clear memory breakpoints. */
+ for (i = 0; i < KGDB_MAX_BREAKPOINTS; i++) {
+ if (kgdb_break[i].state != BP_SET)
+ continue;
+ addr = kgdb_break[i].bpt_addr;
+ error = kgdb_arch_remove_breakpoint(addr,
+ kgdb_break[i].saved_instr);
+ if