diff options
author | Ingo Molnar <mingo@kernel.org> | 2014-06-05 11:18:34 +0200 |
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committer | Ingo Molnar <mingo@kernel.org> | 2014-06-05 12:26:50 +0200 |
commit | 10b0256496fd6c162478547f7c6df1e052e87644 (patch) | |
tree | 7037905737ae83a86a5cdb376cd1d66f7f407e2e /arch/x86/kernel/kprobes/core.c | |
parent | c56d34064b6eb9f9cde9e35bbfe16eedf3d81f94 (diff) | |
parent | 69902c718c0b476e94ed7fccd3cf29ca39fe433a (diff) | |
download | op-kernel-dev-10b0256496fd6c162478547f7c6df1e052e87644.zip op-kernel-dev-10b0256496fd6c162478547f7c6df1e052e87644.tar.gz |
Merge branch 'perf/kprobes' into perf/core
Conflicts:
arch/x86/kernel/traps.c
The kprobes enhancements are fully cooked, ship them upstream.
Signed-off-by: Ingo Molnar <mingo@kernel.org>
Diffstat (limited to 'arch/x86/kernel/kprobes/core.c')
-rw-r--r-- | arch/x86/kernel/kprobes/core.c | 128 |
1 files changed, 70 insertions, 58 deletions
diff --git a/arch/x86/kernel/kprobes/core.c b/arch/x86/kernel/kprobes/core.c index 61b17dc..7596df6 100644 --- a/arch/x86/kernel/kprobes/core.c +++ b/arch/x86/kernel/kprobes/core.c @@ -112,7 +112,8 @@ struct kretprobe_blackpoint kretprobe_blacklist[] = { const int kretprobe_blacklist_size = ARRAY_SIZE(kretprobe_blacklist); -static void __kprobes __synthesize_relative_insn(void *from, void *to, u8 op) +static nokprobe_inline void +__synthesize_relative_insn(void *from, void *to, u8 op) { struct __arch_relative_insn { u8 op; @@ -125,21 +126,23 @@ static void __kprobes __synthesize_relative_insn(void *from, void *to, u8 op) } /* Insert a jump instruction at address 'from', which jumps to address 'to'.*/ -void __kprobes synthesize_reljump(void *from, void *to) +void synthesize_reljump(void *from, void *to) { __synthesize_relative_insn(from, to, RELATIVEJUMP_OPCODE); } +NOKPROBE_SYMBOL(synthesize_reljump); /* Insert a call instruction at address 'from', which calls address 'to'.*/ -void __kprobes synthesize_relcall(void *from, void *to) +void synthesize_relcall(void *from, void *to) { __synthesize_relative_insn(from, to, RELATIVECALL_OPCODE); } +NOKPROBE_SYMBOL(synthesize_relcall); /* * Skip the prefixes of the instruction. */ -static kprobe_opcode_t *__kprobes skip_prefixes(kprobe_opcode_t *insn) +static kprobe_opcode_t *skip_prefixes(kprobe_opcode_t *insn) { insn_attr_t attr; @@ -154,12 +157,13 @@ static kprobe_opcode_t *__kprobes skip_prefixes(kprobe_opcode_t *insn) #endif return insn; } +NOKPROBE_SYMBOL(skip_prefixes); /* * Returns non-zero if opcode is boostable. * RIP relative instructions are adjusted at copying time in 64 bits mode */ -int __kprobes can_boost(kprobe_opcode_t *opcodes) +int can_boost(kprobe_opcode_t *opcodes) { kprobe_opcode_t opcode; kprobe_opcode_t *orig_opcodes = opcodes; @@ -260,7 +264,7 @@ unsigned long recover_probed_instruction(kprobe_opcode_t *buf, unsigned long add } /* Check if paddr is at an instruction boundary */ -static int __kprobes can_probe(unsigned long paddr) +static int can_probe(unsigned long paddr) { unsigned long addr, __addr, offset = 0; struct insn insn; @@ -299,7 +303,7 @@ static int __kprobes can_probe(unsigned long paddr) /* * Returns non-zero if opcode modifies the interrupt flag. */ -static int __kprobes is_IF_modifier(kprobe_opcode_t *insn) +static int is_IF_modifier(kprobe_opcode_t *insn) { /* Skip prefixes */ insn = skip_prefixes(insn); @@ -322,7 +326,7 @@ static int __kprobes is_IF_modifier(kprobe_opcode_t *insn) * If not, return null. * Only applicable to 64-bit x86. */ -int __kprobes __copy_instruction(u8 *dest, u8 *src) +int __copy_instruction(u8 *dest, u8 *src) { struct insn insn; kprobe_opcode_t buf[MAX_INSN_SIZE]; @@ -365,7 +369,7 @@ int __kprobes __copy_instruction(u8 *dest, u8 *src) return insn.length; } -static int __kprobes arch_copy_kprobe(struct kprobe *p) +static int arch_copy_kprobe(struct kprobe *p) { int ret; @@ -392,7 +396,7 @@ static int __kprobes arch_copy_kprobe(struct kprobe *p) return 0; } -int __kprobes arch_prepare_kprobe(struct kprobe *p) +int arch_prepare_kprobe(struct kprobe *p) { if (alternatives_text_reserved(p->addr, p->addr)) return -EINVAL; @@ -407,17 +411,17 @@ int __kprobes arch_prepare_kprobe(struct kprobe *p) return arch_copy_kprobe(p); } -void __kprobes arch_arm_kprobe(struct kprobe *p) +void arch_arm_kprobe(struct kprobe *p) { text_poke(p->addr, ((unsigned char []){BREAKPOINT_INSTRUCTION}), 1); } -void __kprobes arch_disarm_kprobe(struct kprobe *p) +void arch_disarm_kprobe(struct kprobe *p) { text_poke(p->addr, &p->opcode, 1); } -void __kprobes arch_remove_kprobe(struct kprobe *p) +void arch_remove_kprobe(struct kprobe *p) { if (p->ainsn.insn) { free_insn_slot(p->ainsn.insn, (p->ainsn.boostable == 1)); @@ -425,7 +429,8 @@ void __kprobes arch_remove_kprobe(struct kprobe *p) } } -static void __kprobes save_previous_kprobe(struct kprobe_ctlblk *kcb) +static nokprobe_inline void +save_previous_kprobe(struct kprobe_ctlblk *kcb) { kcb->prev_kprobe.kp = kprobe_running(); kcb->prev_kprobe.status = kcb->kprobe_status; @@ -433,7 +438,8 @@ static void __kprobes save_previous_kprobe(struct kprobe_ctlblk *kcb) kcb->prev_kprobe.saved_flags = kcb->kprobe_saved_flags; } -static void __kprobes restore_previous_kprobe(struct kprobe_ctlblk *kcb) +static nokprobe_inline void +restore_previous_kprobe(struct kprobe_ctlblk *kcb) { __this_cpu_write(current_kprobe, kcb->prev_kprobe.kp); kcb->kprobe_status = kcb->prev_kprobe.status; @@ -441,8 +447,9 @@ static void __kprobes restore_previous_kprobe(struct kprobe_ctlblk *kcb) kcb->kprobe_saved_flags = kcb->prev_kprobe.saved_flags; } -static void __kprobes set_current_kprobe(struct kprobe *p, struct pt_regs *regs, - struct kprobe_ctlblk *kcb) +static nokprobe_inline void +set_current_kprobe(struct kprobe *p, struct pt_regs *regs, + struct kprobe_ctlblk *kcb) { __this_cpu_write(current_kprobe, p); kcb->kprobe_saved_flags = kcb->kprobe_old_flags @@ -451,7 +458,7 @@ static void __kprobes set_current_kprobe(struct kprobe *p, struct pt_regs *regs, kcb->kprobe_saved_flags &= ~X86_EFLAGS_IF; } -static void __kprobes clear_btf(void) +static nokprobe_inline void clear_btf(void) { if (test_thread_flag(TIF_BLOCKSTEP)) { unsigned long debugctl = get_debugctlmsr(); @@ -461,7 +468,7 @@ static void __kprobes clear_btf(void) } } -static void __kprobes restore_btf(void) +static nokprobe_inline void restore_btf(void) { if (test_thread_flag(TIF_BLOCKSTEP)) { unsigned long debugctl = get_debugctlmsr(); @@ -471,8 +478,7 @@ static void __kprobes restore_btf(void) } } -void __kprobes -arch_prepare_kretprobe(struct kretprobe_instance *ri, struct pt_regs *regs) +void arch_prepare_kretprobe(struct kretprobe_instance *ri, struct pt_regs *regs) { unsigned long *sara = stack_addr(regs); @@ -481,9 +487,10 @@ arch_prepare_kretprobe(struct kretprobe_instance *ri, struct pt_regs *regs) /* Replace the return addr with trampoline addr */ *sara = (unsigned long) &kretprobe_trampoline; } +NOKPROBE_SYMBOL(arch_prepare_kretprobe); -static void __kprobes -setup_singlestep(struct kprobe *p, struct pt_regs *regs, struct kprobe_ctlblk *kcb, int reenter) +static void setup_singlestep(struct kprobe *p, struct pt_regs *regs, + struct kprobe_ctlblk *kcb, int reenter) { if (setup_detour_execution(p, regs, reenter)) return; @@ -519,22 +526,24 @@ setup_singlestep(struct kprobe *p, struct pt_regs *regs, struct kprobe_ctlblk *k else regs->ip = (unsigned long)p->ainsn.insn; } +NOKPROBE_SYMBOL(setup_singlestep); /* * We have reentered the kprobe_handler(), since another probe was hit while * within the handler. We save the original kprobes variables and just single * step on the instruction of the new probe without calling any user handlers. */ -static int __kprobes -reenter_kprobe(struct kprobe *p, struct pt_regs *regs, struct kprobe_ctlblk *kcb) +static int reenter_kprobe(struct kprobe *p, struct pt_regs *regs, + struct kprobe_ctlblk *kcb) { switch (kcb->kprobe_status) { case KPROBE_HIT_SSDONE: case KPROBE_HIT_ACTIVE: + case KPROBE_HIT_SS: kprobes_inc_nmissed_count(p); setup_singlestep(p, regs, kcb, 1); break; - case KPROBE_HIT_SS: + case KPROBE_REENTER: /* A probe has been hit in the codepath leading up to, or just * after, single-stepping of a probed instruction. This entire * codepath should strictly reside in .kprobes.text section. @@ -553,12 +562,13 @@ reenter_kprobe(struct kprobe *p, struct pt_regs *regs, struct kprobe_ctlblk *kcb return 1; } +NOKPROBE_SYMBOL(reenter_kprobe); /* * Interrupts are disabled on entry as trap3 is an interrupt gate and they * remain disabled throughout this function. */ -static int __kprobes kprobe_handler(struct pt_regs *regs) +int kprobe_int3_handler(struct pt_regs *regs) { kprobe_opcode_t *addr; struct kprobe *p; @@ -621,12 +631,13 @@ static int __kprobes kprobe_handler(struct pt_regs *regs) preempt_enable_no_resched(); return 0; } +NOKPROBE_SYMBOL(kprobe_int3_handler); /* * When a retprobed function returns, this code saves registers and * calls trampoline_handler() runs, which calls the kretprobe's handler. */ -static void __used __kprobes kretprobe_trampoline_holder(void) +static void __used kretprobe_trampoline_holder(void) { asm volatile ( ".global kretprobe_trampoline\n" @@ -657,11 +668,13 @@ static void __used __kprobes kretprobe_trampoline_holder(void) #endif " ret\n"); } +NOKPROBE_SYMBOL(kretprobe_trampoline_holder); +NOKPROBE_SYMBOL(kretprobe_trampoline); /* * Called from kretprobe_trampoline */ -__visible __used __kprobes void *trampoline_handler(struct pt_regs *regs) +__visible __used void *trampoline_handler(struct pt_regs *regs) { struct kretprobe_instance *ri = NULL; struct hlist_head *head, empty_rp; @@ -747,6 +760,7 @@ __visible __used __kprobes void *trampoline_handler(struct pt_regs *regs) } return (void *)orig_ret_address; } +NOKPROBE_SYMBOL(trampoline_handler); /* * Called after single-stepping. p->addr is the address of the @@ -775,8 +789,8 @@ __visible __used __kprobes void *trampoline_handler(struct pt_regs *regs) * jump instruction after the copied instruction, that jumps to the next * instruction after the probepoint. */ -static void __kprobes -resume_execution(struct kprobe *p, struct pt_regs *regs, struct kprobe_ctlblk *kcb) +static void resume_execution(struct kprobe *p, struct pt_regs *regs, + struct kprobe_ctlblk *kcb) { unsigned long *tos = stack_addr(regs); unsigned long copy_ip = (unsigned long)p->ainsn.insn; @@ -851,12 +865,13 @@ resume_execution(struct kprobe *p, struct pt_regs *regs, struct kprobe_ctlblk *k no_change: restore_btf(); } +NOKPROBE_SYMBOL(resume_execution); /* * Interrupts are disabled on entry as trap1 is an interrupt gate and they * remain disabled throughout this function. */ -static int __kprobes post_kprobe_handler(struct pt_regs *regs) +int kprobe_debug_handler(struct pt_regs *regs) { struct kprobe *cur = kprobe_running(); struct kprobe_ctlblk *kcb = get_kprobe_ctlblk(); @@ -891,8 +906,9 @@ out: return 1; } +NOKPROBE_SYMBOL(kprobe_debug_handler); -int __kprobes kprobe_fault_handler(struct pt_regs *regs, int trapnr) +int kprobe_fault_handler(struct pt_regs *regs, int trapnr) { struct kprobe *cur = kprobe_running(); struct kprobe_ctlblk *kcb = get_kprobe_ctlblk(); @@ -949,12 +965,13 @@ int __kprobes kprobe_fault_handler(struct pt_regs *regs, int trapnr) return 0; } +NOKPROBE_SYMBOL(kprobe_fault_handler); /* * Wrapper routine for handling exceptions. */ -int __kprobes -kprobe_exceptions_notify(struct notifier_block *self, unsigned long val, void *data) +int kprobe_exceptions_notify(struct notifier_block *self, unsigned long val, + void *data) { struct die_args *args = data; int ret = NOTIFY_DONE; @@ -962,22 +979,7 @@ kprobe_exceptions_notify(struct notifier_block *self, unsigned long val, void *d if (args->regs && user_mode_vm(args->regs)) return ret; - switch (val) { - case DIE_INT3: - if (kprobe_handler(args->regs)) - ret = NOTIFY_STOP; - break; - case DIE_DEBUG: - if (post_kprobe_handler(args->regs)) { - /* - * Reset the BS bit in dr6 (pointed by args->err) to - * denote completion of processing - */ - (*(unsigned long *)ERR_PTR(args->err)) &= ~DR_STEP; - ret = NOTIFY_STOP; - } - break; - case DIE_GPF: + if (val == DIE_GPF) { /* * To be potentially processing a kprobe fault and to * trust the result from kprobe_running(), we have @@ -986,14 +988,12 @@ kprobe_exceptions_notify(struct notifier_block *self, unsigned long val, void *d if (!preemptible() && kprobe_running() && kprobe_fault_handler(args->regs, args->trapnr)) ret = NOTIFY_STOP; - break; - default: - break; } return ret; } +NOKPROBE_SYMBOL(kprobe_exceptions_notify); -int __kprobes setjmp_pre_handler(struct kprobe *p, struct pt_regs *regs) +int setjmp_pre_handler(struct kprobe *p, struct pt_regs *regs) { struct jprobe *jp = container_of(p, struct jprobe, kp); unsigned long addr; @@ -1017,8 +1017,9 @@ int __kprobes setjmp_pre_handler(struct kprobe *p, struct pt_regs *regs) regs->ip = (unsigned long)(jp->entry); return 1; } +NOKPROBE_SYMBOL(setjmp_pre_handler); -void __kprobes jprobe_return(void) +void jprobe_return(void) { struct kprobe_ctlblk *kcb = get_kprobe_ctlblk(); @@ -1034,8 +1035,10 @@ void __kprobes jprobe_return(void) " nop \n"::"b" (kcb->jprobe_saved_sp):"memory"); } +NOKPROBE_SYMBOL(jprobe_return); +NOKPROBE_SYMBOL(jprobe_return_end); -int __kprobes longjmp_break_handler(struct kprobe *p, struct pt_regs *regs) +int longjmp_break_handler(struct kprobe *p, struct pt_regs *regs) { struct kprobe_ctlblk *kcb = get_kprobe_ctlblk(); u8 *addr = (u8 *) (regs->ip - 1); @@ -1063,13 +1066,22 @@ int __kprobes longjmp_break_handler(struct kprobe *p, struct pt_regs *regs) } return 0; } +NOKPROBE_SYMBOL(longjmp_break_handler); + +bool arch_within_kprobe_blacklist(unsigned long addr) +{ + return (addr >= (unsigned long)__kprobes_text_start && + addr < (unsigned long)__kprobes_text_end) || + (addr >= (unsigned long)__entry_text_start && + addr < (unsigned long)__entry_text_end); +} int __init arch_init_kprobes(void) { return 0; } -int __kprobes arch_trampoline_kprobe(struct kprobe *p) +int arch_trampoline_kprobe(struct kprobe *p) { return 0; } |