From 25c74b10bacead867478480170083f69cfc0db48 Mon Sep 17 00:00:00 2001 From: Seiji Aguchi Date: Wed, 30 Oct 2013 16:37:00 -0400 Subject: x86, trace: Register exception handler to trace IDT This patch registers exception handlers for tracing to a trace IDT. To implemented it in set_intr_gate(), this patch does followings. - Register the exception handlers to the trace IDT by prepending "trace_" to the handler's names. - Also, newly introduce trace_page_fault() to add tracepoints in a subsequent patch. Signed-off-by: Seiji Aguchi Link: http://lkml.kernel.org/r/52716DEC.5050204@hds.com Signed-off-by: H. Peter Anvin --- arch/x86/include/asm/desc.h | 28 +++++++++++++++++++++++----- arch/x86/include/asm/hw_irq.h | 3 +++ arch/x86/include/asm/segment.h | 3 +++ arch/x86/include/asm/traps.h | 20 ++++++++++++++++++++ arch/x86/kernel/entry_32.S | 10 ++++++++++ arch/x86/kernel/entry_64.S | 13 ++++++++++++- arch/x86/kernel/head64.c | 2 +- arch/x86/kernel/kvm.c | 2 +- arch/x86/kernel/traps.c | 28 ++++++++++++++-------------- arch/x86/mm/fault.c | 10 ++++++++++ 10 files changed, 97 insertions(+), 22 deletions(-) (limited to 'arch') diff --git a/arch/x86/include/asm/desc.h b/arch/x86/include/asm/desc.h index d939567..3d73437 100644 --- a/arch/x86/include/asm/desc.h +++ b/arch/x86/include/asm/desc.h @@ -327,10 +327,25 @@ static inline void write_trace_idt_entry(int entry, const gate_desc *gate) { write_idt_entry(trace_idt_table, entry, gate); } + +static inline void _trace_set_gate(int gate, unsigned type, void *addr, + unsigned dpl, unsigned ist, unsigned seg) +{ + gate_desc s; + + pack_gate(&s, type, (unsigned long)addr, dpl, ist, seg); + /* + * does not need to be atomic because it is only done once at + * setup time + */ + write_trace_idt_entry(gate, &s); +} #else static inline void write_trace_idt_entry(int entry, const gate_desc *gate) { } + +#define _trace_set_gate(gate, type, addr, dpl, ist, seg) #endif static inline void _set_gate(int gate, unsigned type, void *addr, @@ -353,11 +368,14 @@ static inline void _set_gate(int gate, unsigned type, void *addr, * Pentium F0 0F bugfix can have resulted in the mapped * IDT being write-protected. */ -static inline void set_intr_gate(unsigned int n, void *addr) -{ - BUG_ON((unsigned)n > 0xFF); - _set_gate(n, GATE_INTERRUPT, addr, 0, 0, __KERNEL_CS); -} +#define set_intr_gate(n, addr) \ + do { \ + BUG_ON((unsigned)n > 0xFF); \ + _set_gate(n, GATE_INTERRUPT, (void *)addr, 0, 0, \ + __KERNEL_CS); \ + _trace_set_gate(n, GATE_INTERRUPT, (void *)trace_##addr,\ + 0, 0, __KERNEL_CS); \ + } while (0) extern int first_system_vector; /* used_vectors is BITMAP for irq is not managed by percpu vector_irq */ diff --git a/arch/x86/include/asm/hw_irq.h b/arch/x86/include/asm/hw_irq.h index 92b3bae..cba45d9 100644 --- a/arch/x86/include/asm/hw_irq.h +++ b/arch/x86/include/asm/hw_irq.h @@ -187,6 +187,9 @@ extern __visible void smp_invalidate_interrupt(struct pt_regs *); #endif extern void (*__initconst interrupt[NR_VECTORS-FIRST_EXTERNAL_VECTOR])(void); +#ifdef CONFIG_TRACING +#define trace_interrupt interrupt +#endif typedef int vector_irq_t[NR_VECTORS]; DECLARE_PER_CPU(vector_irq_t, vector_irq); diff --git a/arch/x86/include/asm/segment.h b/arch/x86/include/asm/segment.h index c48a950..6f1c3a8 100644 --- a/arch/x86/include/asm/segment.h +++ b/arch/x86/include/asm/segment.h @@ -214,6 +214,9 @@ #ifdef __KERNEL__ #ifndef __ASSEMBLY__ extern const char early_idt_handlers[NUM_EXCEPTION_VECTORS][2+2+5]; +#ifdef CONFIG_TRACING +#define trace_early_idt_handlers early_idt_handlers +#endif /* * Load a segment. Fall back on loading the zero diff --git a/arch/x86/include/asm/traps.h b/arch/x86/include/asm/traps.h index 7036cb6..58d66fe 100644 --- a/arch/x86/include/asm/traps.h +++ b/arch/x86/include/asm/traps.h @@ -37,6 +37,23 @@ asmlinkage void machine_check(void); #endif /* CONFIG_X86_MCE */ asmlinkage void simd_coprocessor_error(void); +#ifdef CONFIG_TRACING +asmlinkage void trace_page_fault(void); +#define trace_divide_error divide_error +#define trace_bounds bounds +#define trace_invalid_op invalid_op +#define trace_device_not_available device_not_available +#define trace_coprocessor_segment_overrun coprocessor_segment_overrun +#define trace_invalid_TSS invalid_TSS +#define trace_segment_not_present segment_not_present +#define trace_general_protection general_protection +#define trace_spurious_interrupt_bug spurious_interrupt_bug +#define trace_coprocessor_error coprocessor_error +#define trace_alignment_check alignment_check +#define trace_simd_coprocessor_error simd_coprocessor_error +#define trace_async_page_fault async_page_fault +#endif + dotraplinkage void do_divide_error(struct pt_regs *, long); dotraplinkage void do_debug(struct pt_regs *, long); dotraplinkage void do_nmi(struct pt_regs *, long); @@ -55,6 +72,9 @@ asmlinkage __kprobes struct pt_regs *sync_regs(struct pt_regs *); #endif dotraplinkage void do_general_protection(struct pt_regs *, long); dotraplinkage void do_page_fault(struct pt_regs *, unsigned long); +#ifdef CONFIG_TRACING +dotraplinkage void trace_do_page_fault(struct pt_regs *, unsigned long); +#endif dotraplinkage void do_spurious_interrupt_bug(struct pt_regs *, long); dotraplinkage void do_coprocessor_error(struct pt_regs *, long); dotraplinkage void do_alignment_check(struct pt_regs *, long); diff --git a/arch/x86/kernel/entry_32.S b/arch/x86/kernel/entry_32.S index f0dcb0c..0661abe 100644 --- a/arch/x86/kernel/entry_32.S +++ b/arch/x86/kernel/entry_32.S @@ -1247,6 +1247,16 @@ return_to_handler: */ .pushsection .kprobes.text, "ax" +#ifdef CONFIG_TRACING +ENTRY(trace_page_fault) + RING0_EC_FRAME + ASM_CLAC + pushl_cfi $trace_do_page_fault + jmp error_code + CFI_ENDPROC +END(trace_page_fault) +#endif + ENTRY(page_fault) RING0_EC_FRAME ASM_CLAC diff --git a/arch/x86/kernel/entry_64.S b/arch/x86/kernel/entry_64.S index b077f4c..8b7b169 100644 --- a/arch/x86/kernel/entry_64.S +++ b/arch/x86/kernel/entry_64.S @@ -1280,6 +1280,17 @@ ENTRY(\sym) END(\sym) .endm +#ifdef CONFIG_TRACING +.macro trace_errorentry sym do_sym +errorentry trace(\sym) trace(\do_sym) +errorentry \sym \do_sym +.endm +#else +.macro trace_errorentry sym do_sym +errorentry \sym \do_sym +.endm +#endif + /* error code is on the stack already */ .macro paranoiderrorentry sym do_sym ENTRY(\sym) @@ -1482,7 +1493,7 @@ zeroentry xen_int3 do_int3 errorentry xen_stack_segment do_stack_segment #endif errorentry general_protection do_general_protection -errorentry page_fault do_page_fault +trace_errorentry page_fault do_page_fault #ifdef CONFIG_KVM_GUEST errorentry async_page_fault do_async_page_fault #endif diff --git a/arch/x86/kernel/head64.c b/arch/x86/kernel/head64.c index 1be8e43..85126cc 100644 --- a/arch/x86/kernel/head64.c +++ b/arch/x86/kernel/head64.c @@ -162,7 +162,7 @@ asmlinkage void __init x86_64_start_kernel(char * real_mode_data) clear_bss(); for (i = 0; i < NUM_EXCEPTION_VECTORS; i++) - set_intr_gate(i, &early_idt_handlers[i]); + set_intr_gate(i, early_idt_handlers[i]); load_idt((const struct desc_ptr *)&idt_descr); copy_bootdata(__va(real_mode_data)); diff --git a/arch/x86/kernel/kvm.c b/arch/x86/kernel/kvm.c index b2046e4..6dd802c 100644 --- a/arch/x86/kernel/kvm.c +++ b/arch/x86/kernel/kvm.c @@ -464,7 +464,7 @@ static struct notifier_block kvm_cpu_notifier = { static void __init kvm_apf_trap_init(void) { - set_intr_gate(14, &async_page_fault); + set_intr_gate(14, async_page_fault); } void __init kvm_guest_init(void) diff --git a/arch/x86/kernel/traps.c b/arch/x86/kernel/traps.c index 8c8093b..1c9d0ad 100644 --- a/arch/x86/kernel/traps.c +++ b/arch/x86/kernel/traps.c @@ -713,7 +713,7 @@ void __init early_trap_init(void) /* int3 can be called from all */ set_system_intr_gate_ist(X86_TRAP_BP, &int3, DEBUG_STACK); #ifdef CONFIG_X86_32 - set_intr_gate(X86_TRAP_PF, &page_fault); + set_intr_gate(X86_TRAP_PF, page_fault); #endif load_idt(&idt_descr); } @@ -721,7 +721,7 @@ void __init early_trap_init(void) void __init early_trap_pf_init(void) { #ifdef CONFIG_X86_64 - set_intr_gate(X86_TRAP_PF, &page_fault); + set_intr_gate(X86_TRAP_PF, page_fault); #endif } @@ -737,30 +737,30 @@ void __init trap_init(void) early_iounmap(p, 4); #endif - set_intr_gate(X86_TRAP_DE, ÷_error); + set_intr_gate(X86_TRAP_DE, divide_error); set_intr_gate_ist(X86_TRAP_NMI, &nmi, NMI_STACK); /* int4 can be called from all */ set_system_intr_gate(X86_TRAP_OF, &overflow); - set_intr_gate(X86_TRAP_BR, &bounds); - set_intr_gate(X86_TRAP_UD, &invalid_op); - set_intr_gate(X86_TRAP_NM, &device_not_available); + set_intr_gate(X86_TRAP_BR, bounds); + set_intr_gate(X86_TRAP_UD, invalid_op); + set_intr_gate(X86_TRAP_NM, device_not_available); #ifdef CONFIG_X86_32 set_task_gate(X86_TRAP_DF, GDT_ENTRY_DOUBLEFAULT_TSS); #else set_intr_gate_ist(X86_TRAP_DF, &double_fault, DOUBLEFAULT_STACK); #endif - set_intr_gate(X86_TRAP_OLD_MF, &coprocessor_segment_overrun); - set_intr_gate(X86_TRAP_TS, &invalid_TSS); - set_intr_gate(X86_TRAP_NP, &segment_not_present); + set_intr_gate(X86_TRAP_OLD_MF, coprocessor_segment_overrun); + set_intr_gate(X86_TRAP_TS, invalid_TSS); + set_intr_gate(X86_TRAP_NP, segment_not_present); set_intr_gate_ist(X86_TRAP_SS, &stack_segment, STACKFAULT_STACK); - set_intr_gate(X86_TRAP_GP, &general_protection); - set_intr_gate(X86_TRAP_SPURIOUS, &spurious_interrupt_bug); - set_intr_gate(X86_TRAP_MF, &coprocessor_error); - set_intr_gate(X86_TRAP_AC, &alignment_check); + set_intr_gate(X86_TRAP_GP, general_protection); + set_intr_gate(X86_TRAP_SPURIOUS, spurious_interrupt_bug); + set_intr_gate(X86_TRAP_MF, coprocessor_error); + set_intr_gate(X86_TRAP_AC, alignment_check); #ifdef CONFIG_X86_MCE set_intr_gate_ist(X86_TRAP_MC, &machine_check, MCE_STACK); #endif - set_intr_gate(X86_TRAP_XF, &simd_coprocessor_error); + set_intr_gate(X86_TRAP_XF, simd_coprocessor_error); /* Reserve all the builtin and the syscall vector: */ for (i = 0; i < FIRST_EXTERNAL_VECTOR; i++) diff --git a/arch/x86/mm/fault.c b/arch/x86/mm/fault.c index 3aaeffc..fd3e281 100644 --- a/arch/x86/mm/fault.c +++ b/arch/x86/mm/fault.c @@ -1231,3 +1231,13 @@ do_page_fault(struct pt_regs *regs, unsigned long error_code) __do_page_fault(regs, error_code); exception_exit(prev_state); } + +dotraplinkage void __kprobes +trace_do_page_fault(struct pt_regs *regs, unsigned long error_code) +{ + enum ctx_state prev_state; + + prev_state = exception_enter(); + __do_page_fault(regs, error_code); + exception_exit(prev_state); +} -- cgit v1.1