diff options
Diffstat (limited to 'arch')
| -rw-r--r-- | arch/x86/include/asm/processor.h | 2 | ||||
| -rw-r--r-- | arch/x86/kernel/cpu/common.c | 29 | ||||
| -rw-r--r-- | arch/x86/kernel/early_printk.c | 8 | ||||
| -rw-r--r-- | arch/x86/kernel/kgdb.c | 47 | ||||
| -rw-r--r-- | arch/x86/kernel/setup.c | 1 | ||||
| -rw-r--r-- | arch/x86/kernel/traps.c | 14 |
6 files changed, 76 insertions, 25 deletions
diff --git a/arch/x86/include/asm/processor.h b/arch/x86/include/asm/processor.h index 5a51379dcbe4..7e5c6a60b8ee 100644 --- a/arch/x86/include/asm/processor.h +++ b/arch/x86/include/asm/processor.h @@ -789,6 +789,8 @@ static inline void wbinvd_halt(void) extern void enable_sep_cpu(void); extern int sysenter_setup(void); +extern void early_trap_init(void); + /* Defined in head.S */ extern struct desc_ptr early_gdt_descr; diff --git a/arch/x86/kernel/cpu/common.c b/arch/x86/kernel/cpu/common.c index c1c00d0b1692..cc83a002786e 100644 --- a/arch/x86/kernel/cpu/common.c +++ b/arch/x86/kernel/cpu/common.c @@ -1084,6 +1084,20 @@ static void clear_all_debug_regs(void) } } +#ifdef CONFIG_KGDB +/* + * Restore debug regs if using kgdbwait and you have a kernel debugger + * connection established. + */ +static void dbg_restore_debug_regs(void) +{ + if (unlikely(kgdb_connected && arch_kgdb_ops.correct_hw_break)) + arch_kgdb_ops.correct_hw_break(); +} +#else /* ! CONFIG_KGDB */ +#define dbg_restore_debug_regs() +#endif /* ! CONFIG_KGDB */ + /* * cpu_init() initializes state that is per-CPU. Some data is already * initialized (naturally) in the bootstrap process, such as the GDT @@ -1174,18 +1188,8 @@ void __cpuinit cpu_init(void) load_TR_desc(); load_LDT(&init_mm.context); -#ifdef CONFIG_KGDB - /* - * If the kgdb is connected no debug regs should be altered. This - * is only applicable when KGDB and a KGDB I/O module are built - * into the kernel and you are using early debugging with - * kgdbwait. KGDB will control the kernel HW breakpoint registers. - */ - if (kgdb_connected && arch_kgdb_ops.correct_hw_break) - arch_kgdb_ops.correct_hw_break(); - else -#endif - clear_all_debug_regs(); + clear_all_debug_regs(); + dbg_restore_debug_regs(); fpu_init(); @@ -1239,6 +1243,7 @@ void __cpuinit cpu_init(void) #endif clear_all_debug_regs(); + dbg_restore_debug_regs(); /* * Force FPU initialization: diff --git a/arch/x86/kernel/early_printk.c b/arch/x86/kernel/early_printk.c index b9c830c12b4a..fa99bae75ace 100644 --- a/arch/x86/kernel/early_printk.c +++ b/arch/x86/kernel/early_printk.c @@ -41,6 +41,14 @@ static void early_vga_write(struct console *con, const char *str, unsigned n) writew(0x720, VGABASE + 2*(max_xpos*j + i)); current_ypos = max_ypos-1; } +#ifdef CONFIG_KGDB_KDB + if (c == '\b') { + if (current_xpos > 0) + current_xpos--; + } else if (c == '\r') { + current_xpos = 0; + } else +#endif if (c == '\n') { current_xpos = 0; current_ypos++; diff --git a/arch/x86/kernel/kgdb.c b/arch/x86/kernel/kgdb.c index 95b89d4cb8f1..4f4af75b9482 100644 --- a/arch/x86/kernel/kgdb.c +++ b/arch/x86/kernel/kgdb.c @@ -199,6 +199,8 @@ static struct hw_breakpoint { struct perf_event **pev; } breakinfo[4]; +static unsigned long early_dr7; + static void kgdb_correct_hw_break(void) { int breakno; @@ -210,6 +212,14 @@ static void kgdb_correct_hw_break(void) int cpu = raw_smp_processor_id(); if (!breakinfo[breakno].enabled) continue; + if (dbg_is_early) { + set_debugreg(breakinfo[breakno].addr, breakno); + early_dr7 |= encode_dr7(breakno, + breakinfo[breakno].len, + breakinfo[breakno].type); + set_debugreg(early_dr7, 7); + continue; + } bp = *per_cpu_ptr(breakinfo[breakno].pev, cpu); info = counter_arch_bp(bp); if (bp->attr.disabled != 1) @@ -224,7 +234,8 @@ static void kgdb_correct_hw_break(void) if (!val) bp->attr.disabled = 0; } - hw_breakpoint_restore(); + if (!dbg_is_early) + hw_breakpoint_restore(); } static int hw_break_reserve_slot(int breakno) @@ -233,6 +244,9 @@ static int hw_break_reserve_slot(int breakno) int cnt = 0; struct perf_event **pevent; + if (dbg_is_early) + return 0; + for_each_online_cpu(cpu) { cnt++; pevent = per_cpu_ptr(breakinfo[breakno].pev, cpu); @@ -258,6 +272,9 @@ static int hw_break_release_slot(int breakno) struct perf_event **pevent; int cpu; + if (dbg_is_early) + return 0; + for_each_online_cpu(cpu) { pevent = per_cpu_ptr(breakinfo[breakno].pev, cpu); if (dbg_release_bp_slot(*pevent)) @@ -302,7 +319,11 @@ static void kgdb_remove_all_hw_break(void) bp = *per_cpu_ptr(breakinfo[i].pev, cpu); if (bp->attr.disabled == 1) continue; - arch_uninstall_hw_breakpoint(bp); + if (dbg_is_early) + early_dr7 &= ~encode_dr7(i, breakinfo[i].len, + breakinfo[i].type); + else + arch_uninstall_hw_breakpoint(bp); bp->attr.disabled = 1; } } @@ -379,6 +400,11 @@ void kgdb_disable_hw_debug(struct pt_regs *regs) for (i = 0; i < 4; i++) { if (!breakinfo[i].enabled) continue; + if (dbg_is_early) { + early_dr7 &= ~encode_dr7(i, breakinfo[i].len, + breakinfo[i].type); + continue; + } bp = *per_cpu_ptr(breakinfo[i].pev, cpu); if (bp->attr.disabled == 1) continue; @@ -596,14 +622,15 @@ static struct notifier_block kgdb_notifier = { */ int kgdb_arch_init(void) { + return register_die_notifier(&kgdb_notifier); +} + +void kgdb_arch_late(void) +{ 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 @@ -615,12 +642,15 @@ int kgdb_arch_init(void) attr.bp_type = HW_BREAKPOINT_W; attr.disabled = 1; for (i = 0; i < 4; i++) { + if (breakinfo[i].pev) + continue; 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"); + printk(KERN_ERR "kgdb: Could not allocate hw" + "breakpoints\nDisabling the kernel debugger\n"); breakinfo[i].pev = NULL; kgdb_arch_exit(); - return -1; + return; } for_each_online_cpu(cpu) { pevent = per_cpu_ptr(breakinfo[i].pev, cpu); @@ -631,7 +661,6 @@ int kgdb_arch_init(void) } } } - return ret; } /** diff --git a/arch/x86/kernel/setup.c b/arch/x86/kernel/setup.c index c4851eff57b3..e8029896309a 100644 --- a/arch/x86/kernel/setup.c +++ b/arch/x86/kernel/setup.c @@ -725,6 +725,7 @@ void __init setup_arch(char **cmdline_p) /* VMI may relocate the fixmap; do this before touching ioremap area */ vmi_init(); + early_trap_init(); early_cpu_init(); early_ioremap_init(); diff --git a/arch/x86/kernel/traps.c b/arch/x86/kernel/traps.c index 7eaad4c5110a..142d70c74b02 100644 --- a/arch/x86/kernel/traps.c +++ b/arch/x86/kernel/traps.c @@ -808,6 +808,16 @@ dotraplinkage void do_iret_error(struct pt_regs *regs, long error_code) } #endif +/* Set of traps needed for early debugging. */ +void __init early_trap_init(void) +{ + set_intr_gate_ist(1, &debug, DEBUG_STACK); + /* int3 can be called from all */ + set_system_intr_gate_ist(3, &int3, DEBUG_STACK); + set_intr_gate(14, &page_fault); + load_idt(&idt_descr); +} + void __init trap_init(void) { int i; @@ -821,10 +831,7 @@ void __init trap_init(void) #endif set_intr_gate(0, ÷_error); - set_intr_gate_ist(1, &debug, DEBUG_STACK); set_intr_gate_ist(2, &nmi, NMI_STACK); - /* int3 can be called from all */ - set_system_intr_gate_ist(3, &int3, DEBUG_STACK); /* int4 can be called from all */ set_system_intr_gate(4, &overflow); set_intr_gate(5, &bounds); @@ -840,7 +847,6 @@ void __init trap_init(void) set_intr_gate(11, &segment_not_present); set_intr_gate_ist(12, &stack_segment, STACKFAULT_STACK); set_intr_gate(13, &general_protection); - set_intr_gate(14, &page_fault); set_intr_gate(15, &spurious_interrupt_bug); set_intr_gate(16, &coprocessor_error); set_intr_gate(17, &alignment_check); |