From 04bb591ca74fb8ea06d5ab7fadfb7bf5b11fb28e Mon Sep 17 00:00:00 2001 From: Andi Kleen Date: Mon, 5 Aug 2013 15:02:41 -0700 Subject: [PATCH] x86, asmlinkage: Make kprobes code visible and fix assembler code - Make all the external assembler template symbols __visible - Move the templates inline assembler code into a top level assembler statement, not inside a function. This avoids it being optimized away or cloned. Cc: Ananth N Mavinakayanahalli Cc: Anil S Keshavamurthy Cc: "David S. Miller" Cc: Masami Hiramatsu Signed-off-by: Andi Kleen Link: http://lkml.kernel.org/r/1375740170-7446-8-git-send-email-andi@firstfloor.org Signed-off-by: H. Peter Anvin --- arch/x86/include/asm/kprobes.h | 10 +++++----- arch/x86/kernel/kprobes/core.c | 2 +- arch/x86/kernel/kprobes/opt.c | 5 +---- 3 files changed, 7 insertions(+), 10 deletions(-) diff --git a/arch/x86/include/asm/kprobes.h b/arch/x86/include/asm/kprobes.h index 5a6d287..9454c16 100644 --- a/arch/x86/include/asm/kprobes.h +++ b/arch/x86/include/asm/kprobes.h @@ -49,10 +49,10 @@ typedef u8 kprobe_opcode_t; #define flush_insn_slot(p) do { } while (0) /* optinsn template addresses */ -extern kprobe_opcode_t optprobe_template_entry; -extern kprobe_opcode_t optprobe_template_val; -extern kprobe_opcode_t optprobe_template_call; -extern kprobe_opcode_t optprobe_template_end; +extern __visible kprobe_opcode_t optprobe_template_entry; +extern __visible kprobe_opcode_t optprobe_template_val; +extern __visible kprobe_opcode_t optprobe_template_call; +extern __visible kprobe_opcode_t optprobe_template_end; #define MAX_OPTIMIZED_LENGTH (MAX_INSN_SIZE + RELATIVE_ADDR_SIZE) #define MAX_OPTINSN_SIZE \ (((unsigned long)&optprobe_template_end - \ @@ -62,7 +62,7 @@ extern kprobe_opcode_t optprobe_template_end; extern const int kretprobe_blacklist_size; void arch_remove_kprobe(struct kprobe *p); -void kretprobe_trampoline(void); +asmlinkage void kretprobe_trampoline(void); /* Architecture specific copy of original instruction*/ struct arch_specific_insn { diff --git a/arch/x86/kernel/kprobes/core.c b/arch/x86/kernel/kprobes/core.c index 211bce4..048852d 100644 --- a/arch/x86/kernel/kprobes/core.c +++ b/arch/x86/kernel/kprobes/core.c @@ -661,7 +661,7 @@ static void __used __kprobes kretprobe_trampoline_holder(void) /* * Called from kretprobe_trampoline */ -static __used __kprobes void *trampoline_handler(struct pt_regs *regs) +__visible __used __kprobes void *trampoline_handler(struct pt_regs *regs) { struct kretprobe_instance *ri = NULL; struct hlist_head *head, empty_rp; diff --git a/arch/x86/kernel/kprobes/opt.c b/arch/x86/kernel/kprobes/opt.c index 76dc6f0..2c1ac28 100644 --- a/arch/x86/kernel/kprobes/opt.c +++ b/arch/x86/kernel/kprobes/opt.c @@ -88,9 +88,7 @@ static void __kprobes synthesize_set_arg1(kprobe_opcode_t *addr, unsigned long v *(unsigned long *)addr = val; } -static void __used __kprobes kprobes_optinsn_template_holder(void) -{ - asm volatile ( +asm ( ".global optprobe_template_entry\n" "optprobe_template_entry:\n" #ifdef CONFIG_X86_64 @@ -129,7 +127,6 @@ static void __used __kprobes kprobes_optinsn_template_holder(void) #endif ".global optprobe_template_end\n" "optprobe_template_end:\n"); -} #define TMPL_MOVE_IDX \ ((long)&optprobe_template_val - (long)&optprobe_template_entry) -- 2.7.4