diff options
| -rw-r--r-- | arch/x86/kernel/entry_32.S | 3 | ||||
| -rw-r--r-- | arch/x86/kernel/entry_64.S | 4 | ||||
| -rw-r--r-- | arch/x86/kernel/kprobes.c | 43 | ||||
| -rw-r--r-- | kernel/Makefile | 2 | ||||
| -rw-r--r-- | kernel/kprobes.c | 3 | ||||
| -rw-r--r-- | kernel/trace/Kconfig | 5 | ||||
| -rw-r--r-- | kernel/trace/Makefile | 6 | ||||
| -rw-r--r-- | kernel/trace/trace_events.c | 4 |
8 files changed, 46 insertions, 24 deletions
diff --git a/arch/x86/kernel/entry_32.S b/arch/x86/kernel/entry_32.S index 061ac17ee974..f438a44bf8f9 100644 --- a/arch/x86/kernel/entry_32.S +++ b/arch/x86/kernel/entry_32.S @@ -1148,7 +1148,6 @@ ENTRY(ftrace_regs_caller) * ip location, and move flags into the return ip location. */ pushl 4(%esp) /* save return ip into ip slot */ - subl $MCOUNT_INSN_SIZE, (%esp) /* Adjust ip */ pushl $0 /* Load 0 into orig_ax */ pushl %gs @@ -1169,6 +1168,7 @@ ENTRY(ftrace_regs_caller) movl $__KERNEL_CS,13*4(%esp) movl 12*4(%esp), %eax /* Load ip (1st parameter) */ + subl $MCOUNT_INSN_SIZE, %eax /* Adjust ip */ movl 0x4(%ebp), %edx /* Load parent ip (2nd parameter) */ leal function_trace_op, %ecx /* Save ftrace_pos in 3rd parameter */ pushl %esp /* Save pt_regs as 4th parameter */ @@ -1180,7 +1180,6 @@ GLOBAL(ftrace_regs_call) movl 14*4(%esp), %eax /* Move flags back into cs */ movl %eax, 13*4(%esp) /* Needed to keep addl from modifying flags */ movl 12*4(%esp), %eax /* Get return ip from regs->ip */ - addl $MCOUNT_INSN_SIZE, %eax movl %eax, 14*4(%esp) /* Put return ip back for ret */ popl %ebx diff --git a/arch/x86/kernel/entry_64.S b/arch/x86/kernel/entry_64.S index ed767b747fe5..e9cc2b32bdf4 100644 --- a/arch/x86/kernel/entry_64.S +++ b/arch/x86/kernel/entry_64.S @@ -165,6 +165,10 @@ GLOBAL(ftrace_regs_call) movq EFLAGS(%rsp), %rax movq %rax, SS(%rsp) + /* Handlers can change the RIP */ + movq RIP(%rsp), %rax + movq %rax, SS+8(%rsp) + /* restore the rest of pt_regs */ movq R15(%rsp), %r15 movq R14(%rsp), %r14 diff --git a/arch/x86/kernel/kprobes.c b/arch/x86/kernel/kprobes.c index 47ae1023a93c..b7c2a85d1926 100644 --- a/arch/x86/kernel/kprobes.c +++ b/arch/x86/kernel/kprobes.c @@ -541,6 +541,8 @@ reenter_kprobe(struct kprobe *p, struct pt_regs *regs, struct kprobe_ctlblk *kcb return 1; } +static void __kprobes skip_singlestep(struct kprobe *p, struct pt_regs *regs, + struct kprobe_ctlblk *kcb); /* * Interrupts are disabled on entry as trap3 is an interrupt gate and they * remain disabled throughout this function. @@ -599,6 +601,12 @@ static int __kprobes kprobe_handler(struct pt_regs *regs) } else if (kprobe_running()) { p = __this_cpu_read(current_kprobe); if (p->break_handler && p->break_handler(p, regs)) { +#ifdef KPROBES_CAN_USE_FTRACE + if (kprobe_ftrace(p)) { + skip_singlestep(p, regs, kcb); + return 1; + } +#endif setup_singlestep(p, regs, kcb, 0); return 1; } @@ -1053,6 +1061,21 @@ int __kprobes longjmp_break_handler(struct kprobe *p, struct pt_regs *regs) } #ifdef KPROBES_CAN_USE_FTRACE +static void __kprobes skip_singlestep(struct kprobe *p, struct pt_regs *regs, + struct kprobe_ctlblk *kcb) +{ + /* + * Emulate singlestep (and also recover regs->ip) + * as if there is a 5byte nop + */ + regs->ip = (unsigned long)p->addr + MCOUNT_INSN_SIZE; + if (unlikely(p->post_handler)) { + kcb->kprobe_status = KPROBE_HIT_SSDONE; + p->post_handler(p, regs, 0); + } + __this_cpu_write(current_kprobe, NULL); +} + /* Ftrace callback handler for kprobes */ void __kprobes kprobe_ftrace_handler(unsigned long ip, unsigned long parent_ip, struct ftrace_ops *ops, struct pt_regs *regs) @@ -1072,21 +1095,17 @@ void __kprobes kprobe_ftrace_handler(unsigned long ip, unsigned long parent_ip, if (kprobe_running()) { kprobes_inc_nmissed_count(p); } else { - regs->ip += sizeof(kprobe_opcode_t); + /* Kprobe handler expects regs->ip = ip + 1 as breakpoint hit */ + regs->ip = ip + sizeof(kprobe_opcode_t); __this_cpu_write(current_kprobe, p); kcb->kprobe_status = KPROBE_HIT_ACTIVE; - if (p->pre_handler) - p->pre_handler(p, regs); - - if (unlikely(p->post_handler)) { - /* Emulate singlestep as if there is a 5byte nop */ - regs->ip = ip + MCOUNT_INSN_SIZE; - kcb->kprobe_status = KPROBE_HIT_SSDONE; - p->post_handler(p, regs, 0); - } - __this_cpu_write(current_kprobe, NULL); - regs->ip = ip; /* Recover for next callback */ + if (!p->pre_handler || !p->pre_handler(p, regs)) + skip_singlestep(p, regs, kcb); + /* + * If pre_handler returns !0, it sets regs->ip and + * resets current kprobe. + */ } end: local_irq_restore(flags); diff --git a/kernel/Makefile b/kernel/Makefile index c0cc67ad764c..29d993be7dba 100644 --- a/kernel/Makefile +++ b/kernel/Makefile @@ -98,7 +98,7 @@ obj-$(CONFIG_COMPAT_BINFMT_ELF) += elfcore.o obj-$(CONFIG_BINFMT_ELF_FDPIC) += elfcore.o obj-$(CONFIG_FUNCTION_TRACER) += trace/ obj-$(CONFIG_TRACING) += trace/ -obj-$(CONFIG_X86_DS) += trace/ +obj-$(CONFIG_TRACE_CLOCK) += trace/ obj-$(CONFIG_RING_BUFFER) += trace/ obj-$(CONFIG_TRACEPOINTS) += trace/ obj-$(CONFIG_IRQ_WORK) += irq_work.o diff --git a/kernel/kprobes.c b/kernel/kprobes.c index 35b4315d84f5..098f396aa409 100644 --- a/kernel/kprobes.c +++ b/kernel/kprobes.c @@ -1418,9 +1418,6 @@ static __kprobes int check_kprobe_address_safe(struct kprobe *p, /* Given address is not on the instruction boundary */ if ((unsigned long)p->addr != ftrace_addr) return -EILSEQ; - /* break_handler (jprobe) can not work with ftrace */ - if (p->break_handler) - return -EINVAL; p->flags |= KPROBE_FLAG_FTRACE; #else /* !KPROBES_CAN_USE_FTRACE */ return -EINVAL; diff --git a/kernel/trace/Kconfig b/kernel/trace/Kconfig index 9301a0e35e0c..4cea4f41c1d9 100644 --- a/kernel/trace/Kconfig +++ b/kernel/trace/Kconfig @@ -62,8 +62,12 @@ config HAVE_C_RECORDMCOUNT config TRACER_MAX_TRACE bool +config TRACE_CLOCK + bool + config RING_BUFFER bool + select TRACE_CLOCK config FTRACE_NMI_ENTER bool @@ -114,6 +118,7 @@ config TRACING select NOP_TRACER select BINARY_PRINTF select EVENT_TRACING + select TRACE_CLOCK config GENERIC_TRACER bool diff --git a/kernel/trace/Makefile b/kernel/trace/Makefile index 837090808aac..d7e2068e4b71 100644 --- a/kernel/trace/Makefile +++ b/kernel/trace/Makefile @@ -19,11 +19,7 @@ endif CFLAGS_trace_events_filter.o := -I$(src) -# -# Make the trace clocks available generally: it's infrastructure -# relied on by ptrace for example: -# -obj-y += trace_clock.o +obj-$(CONFIG_TRACE_CLOCK) += trace_clock.o obj-$(CONFIG_FUNCTION_TRACER) += libftrace.o obj-$(CONFIG_RING_BUFFER) += ring_buffer.o diff --git a/kernel/trace/trace_events.c b/kernel/trace/trace_events.c index 6825d833a257..bbb0e63d78e9 100644 --- a/kernel/trace/trace_events.c +++ b/kernel/trace/trace_events.c @@ -1646,9 +1646,11 @@ static __init void event_trace_self_tests(void) event_test_stuff(); ret = __ftrace_set_clr_event(NULL, system->name, NULL, 0); - if (WARN_ON_ONCE(ret)) + if (WARN_ON_ONCE(ret)) { pr_warning("error disabling system %s\n", system->name); + continue; + } pr_cont("OK\n"); } |