#include <linux/init.h>
#include <linux/smp.h>
#include <linux/nmi.h>
+#include <linux/hw_breakpoint.h>
+#include <asm/debugreg.h>
#include <asm/apicdef.h>
#include <asm/system.h>
-#ifdef CONFIG_X86_32
-# include <mach_ipi.h>
-#else
-# include <asm/mach_apic.h>
-#endif
+#include <asm/apic.h>
/*
* Put the error code here just in case the user cares:
*/
void pt_regs_to_gdb_regs(unsigned long *gdb_regs, struct pt_regs *regs)
{
+#ifndef CONFIG_X86_32
+ u32 *gdb_regs32 = (u32 *)gdb_regs;
+#endif
gdb_regs[GDB_AX] = regs->ax;
gdb_regs[GDB_BX] = regs->bx;
gdb_regs[GDB_CX] = regs->cx;
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_PS] = regs->flags;
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;
+ if (user_mode_vm(regs)) {
+ gdb_regs[GDB_SS] = regs->ss;
+ gdb_regs[GDB_SP] = regs->sp;
+ } else {
+ gdb_regs[GDB_SS] = __KERNEL_DS;
+ gdb_regs[GDB_SP] = kernel_stack_pointer(regs);
+ }
#else
gdb_regs[GDB_R8] = regs->r8;
gdb_regs[GDB_R9] = regs->r9;
gdb_regs[GDB_R13] = regs->r13;
gdb_regs[GDB_R14] = regs->r14;
gdb_regs[GDB_R15] = regs->r15;
+ gdb_regs32[GDB_PS] = regs->flags;
+ gdb_regs32[GDB_CS] = regs->cs;
+ gdb_regs32[GDB_SS] = regs->ss;
+ gdb_regs[GDB_SP] = kernel_stack_pointer(regs);
#endif
- gdb_regs[GDB_SP] = regs->sp;
}
/**
*/
void sleeping_thread_to_gdb_regs(unsigned long *gdb_regs, struct task_struct *p)
{
+#ifndef CONFIG_X86_32
+ u32 *gdb_regs32 = (u32 *)gdb_regs;
+#endif
gdb_regs[GDB_AX] = 0;
gdb_regs[GDB_BX] = 0;
gdb_regs[GDB_CX] = 0;
gdb_regs[GDB_FS] = 0xFFFF;
gdb_regs[GDB_GS] = 0xFFFF;
#else
- gdb_regs[GDB_PS] = *(unsigned long *)(p->thread.sp + 8);
+ gdb_regs32[GDB_PS] = *(unsigned long *)(p->thread.sp + 8);
+ gdb_regs32[GDB_CS] = __KERNEL_CS;
+ gdb_regs32[GDB_SS] = __KERNEL_DS;
gdb_regs[GDB_PC] = 0;
gdb_regs[GDB_R8] = 0;
gdb_regs[GDB_R9] = 0;
*/
void gdb_regs_to_pt_regs(unsigned long *gdb_regs, struct pt_regs *regs)
{
+#ifndef CONFIG_X86_32
+ u32 *gdb_regs32 = (u32 *)gdb_regs;
+#endif
regs->ax = gdb_regs[GDB_AX];
regs->bx = gdb_regs[GDB_BX];
regs->cx = gdb_regs[GDB_CX];
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->flags = gdb_regs[GDB_PS];
regs->ds = gdb_regs[GDB_DS];
regs->es = gdb_regs[GDB_ES];
regs->cs = gdb_regs[GDB_CS];
regs->r13 = gdb_regs[GDB_R13];
regs->r14 = gdb_regs[GDB_R14];
regs->r15 = gdb_regs[GDB_R15];
+ regs->flags = gdb_regs32[GDB_PS];
+ regs->cs = gdb_regs32[GDB_CS];
+ regs->ss = gdb_regs32[GDB_SS];
#endif
}
static struct hw_breakpoint {
unsigned enabled;
- unsigned type;
- unsigned len;
unsigned long addr;
+ int len;
+ int type;
+ struct perf_event **pev;
} 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));
- }
- }
+ struct perf_event *bp;
+ struct arch_hw_breakpoint *info;
+ int val;
+ int cpu = raw_smp_processor_id();
+ if (!breakinfo[breakno].enabled)
+ continue;
+ bp = *per_cpu_ptr(breakinfo[breakno].pev, cpu);
+ info = counter_arch_bp(bp);
+ if (bp->attr.disabled != 1)
+ continue;
+ bp->attr.bp_addr = breakinfo[breakno].addr;
+ bp->attr.bp_len = breakinfo[breakno].len;
+ bp->attr.bp_type = breakinfo[breakno].type;
+ info->address = breakinfo[breakno].addr;
+ info->len = breakinfo[breakno].len;
+ info->type = breakinfo[breakno].type;
+ val = arch_install_hw_breakpoint(bp);
+ if (!val)
+ bp->attr.disabled = 0;
+ }
+ hw_breakpoint_restore();
+}
+
+static int hw_break_reserve_slot(int breakno)
+{
+ int cpu;
+ int cnt = 0;
+ struct perf_event **pevent;
+
+ for_each_online_cpu(cpu) {
+ cnt++;
+ pevent = per_cpu_ptr(breakinfo[breakno].pev, cpu);
+ if (dbg_reserve_bp_slot(*pevent))
+ goto fail;
+ }
+
+ return 0;
+
+fail:
+ for_each_online_cpu(cpu) {
+ cnt--;
+ if (!cnt)
+ break;
+ pevent = per_cpu_ptr(breakinfo[breakno].pev, cpu);
+ dbg_release_bp_slot(*pevent);
+ }
+ return -1;
+}
+
+static int hw_break_release_slot(int breakno)
+{
+ struct perf_event **pevent;
+ int cpu;
+
+ for_each_online_cpu(cpu) {
+ pevent = per_cpu_ptr(breakinfo[breakno].pev, cpu);
+ if (dbg_release_bp_slot(*pevent))
+ /*
+ * The debugger is responisble for handing the retry on
+ * remove failure.
+ */
+ return -1;
}
- if (correctit)
- set_debugreg(dr7, 7);
+ return 0;
}
static int
if (i == 4)
return -1;
+ if (hw_break_release_slot(i)) {
+ printk(KERN_ERR "Cannot remove hw breakpoint at %lx\n", addr);
+ return -1;
+ }
breakinfo[i].enabled = 0;
return 0;
static void kgdb_remove_all_hw_break(void)
{
int i;
+ int cpu = raw_smp_processor_id();
+ struct perf_event *bp;
- for (i = 0; i < 4; i++)
- memset(&breakinfo[i], 0, sizeof(struct hw_breakpoint));
+ for (i = 0; i < 4; i++) {
+ if (!breakinfo[i].enabled)
+ continue;
+ bp = *per_cpu_ptr(breakinfo[i].pev, cpu);
+ if (bp->attr.disabled == 1)
+ continue;
+ arch_uninstall_hw_breakpoint(bp);
+ bp->attr.disabled = 1;
+ }
}
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++)
switch (bptype) {
case BP_HARDWARE_BREAKPOINT:
- type = 0;
- len = 1;
+ len = 1;
+ breakinfo[i].type = X86_BREAKPOINT_EXECUTE;
break;
case BP_WRITE_WATCHPOINT:
- type = 1;
+ breakinfo[i].type = X86_BREAKPOINT_WRITE;
break;
case BP_ACCESS_WATCHPOINT:
- type = 3;
+ breakinfo[i].type = X86_BREAKPOINT_RW;
break;
default:
return -1;
}
-
- if (len == 1 || len == 2 || len == 4)
- breakinfo[i].len = len - 1;
- else
+ switch (len) {
+ case 1:
+ breakinfo[i].len = X86_BREAKPOINT_LEN_1;
+ break;
+ case 2:
+ breakinfo[i].len = X86_BREAKPOINT_LEN_2;
+ break;
+ case 4:
+ breakinfo[i].len = X86_BREAKPOINT_LEN_4;
+ break;
+#ifdef CONFIG_X86_64
+ case 8:
+ breakinfo[i].len = X86_BREAKPOINT_LEN_8;
+ break;
+#endif
+ default:
return -1;
-
- breakinfo[i].enabled = 1;
+ }
breakinfo[i].addr = addr;
- breakinfo[i].type = type;
+ if (hw_break_reserve_slot(i)) {
+ breakinfo[i].addr = 0;
+ return -1;
+ }
+ breakinfo[i].enabled = 1;
return 0;
}
*/
void kgdb_disable_hw_debug(struct pt_regs *regs)
{
+ int i;
+ int cpu = raw_smp_processor_id();
+ struct perf_event *bp;
+
/* Disable hardware debugging while we are in kgdb: */
set_debugreg(0UL, 7);
+ for (i = 0; i < 4; i++) {
+ if (!breakinfo[i].enabled)
+ continue;
+ bp = *per_cpu_ptr(breakinfo[i].pev, cpu);
+ if (bp->attr.disabled == 1)
+ continue;
+ arch_uninstall_hw_breakpoint(bp);
+ bp->attr.disabled = 1;
+ }
}
/**
*/
void kgdb_roundup_cpus(unsigned long flags)
{
- send_IPI_allbutself(APIC_DM_NMI);
+ apic->send_IPI_allbutself(APIC_DM_NMI);
}
#endif
struct pt_regs *linux_regs)
{
unsigned long addr;
- unsigned long dr6;
char *ptr;
int newPC;
newPC = linux_regs->ip;
/* clear the trace bit */
- linux_regs->flags &= ~TF_MASK;
+ linux_regs->flags &= ~X86_EFLAGS_TF;
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());
- }
+ linux_regs->flags |= X86_EFLAGS_TF;
+ 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;
"resuming...\n");
kgdb_arch_handle_exception(args->trapnr, args->signr,
args->err, "c", "", regs);
+ /*
+ * Reset the BS bit in dr6 (pointed by args->err) to
+ * denote completion of processing
+ */
+ (*(unsigned long *)ERR_PTR(args->err)) &= ~DR_STEP;
return NOTIFY_STOP;
}
return NOTIFY_DONE;
case DIE_NMI_IPI:
- if (atomic_read(&kgdb_active) != -1) {
- /* KGDB CPU roundup */
- kgdb_nmicallback(raw_smp_processor_id(), regs);
- was_in_debug_nmi[raw_smp_processor_id()] = 1;
- touch_nmi_watchdog();
- }
+ /* Just ignore, we will handle the roundup on DIE_NMI. */
return NOTIFY_DONE;
case DIE_NMIUNKNOWN:
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);
+ if (atomic_read(&kgdb_cpu_doing_single_step) != -1) {
+ if (user_mode(regs))
+ return single_step_cont(regs, args);
+ break;
+ } else if (test_thread_flag(TIF_SINGLESTEP))
+ /* This means a user thread is single stepping
+ * a system call which should be ignored
+ */
+ return NOTIFY_DONE;
/* fall through */
default:
if (user_mode(regs))
*/
int kgdb_arch_init(void)
{
- return register_die_notifier(&kgdb_notifier);
+ int i, cpu;
+ int ret;
+ struct perf_event_attr attr;
+ struct perf_event **pevent;
+
+ ret = register_die_notifier(&kgdb_notifier);
+ if (ret != 0)
+ return ret;
+ /*
+ * Pre-allocate the hw breakpoint structions in the non-atomic
+ * portion of kgdb because this operation requires mutexs to
+ * complete.
+ */
+ hw_breakpoint_init(&attr);
+ attr.bp_addr = (unsigned long)kgdb_arch_init;
+ attr.bp_len = HW_BREAKPOINT_LEN_1;
+ attr.bp_type = HW_BREAKPOINT_W;
+ attr.disabled = 1;
+ for (i = 0; i < 4; i++) {
+ breakinfo[i].pev = register_wide_hw_breakpoint(&attr, NULL);
+ if (IS_ERR(breakinfo[i].pev)) {
+ printk(KERN_ERR "kgdb: Could not allocate hw breakpoints\n");
+ breakinfo[i].pev = NULL;
+ kgdb_arch_exit();
+ return -1;
+ }
+ for_each_online_cpu(cpu) {
+ pevent = per_cpu_ptr(breakinfo[i].pev, cpu);
+ pevent[0]->hw.sample_period = 1;
+ if (pevent[0]->destroy != NULL) {
+ pevent[0]->destroy = NULL;
+ release_bp_slot(*pevent);
+ }
+ }
+ }
+ return ret;
}
/**
*/
void kgdb_arch_exit(void)
{
+ int i;
+ for (i = 0; i < 4; i++) {
+ if (breakinfo[i].pev) {
+ unregister_wide_hw_breakpoint(breakinfo[i].pev);
+ breakinfo[i].pev = NULL;
+ }
+ }
unregister_die_notifier(&kgdb_notifier);
}
return instruction_pointer(regs);
}
+void kgdb_arch_set_pc(struct pt_regs *regs, unsigned long ip)
+{
+ regs->ip = ip;
+}
+
struct kgdb_arch arch_kgdb_ops = {
/* Breakpoint instruction: */
.gdb_bpt_instr = { 0xcc },
git://ftp.safe.ca / safe / jmp / linux-2.6 / blobdiff