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 <ananth@in.ibm.com>
Cc: Anil S Keshavamurthy <anil.s.keshavamurthy@intel.com>
Cc: "David S. Miller" <davem@davemloft.net>
Cc: Masami Hiramatsu <masami.hiramatsu.pt@hitachi.com>
Signed-off-by: Andi Kleen <ak@linux.intel.com>
Link: http://lkml.kernel.org/r/1375740170-7446-8-git-send-email-andi@firstfloor.org
Signed-off-by: H. Peter Anvin <hpa@linux.intel.com>
This commit is contained in:
Andi Kleen 2013-08-05 15:02:41 -07:00 committed by H. Peter Anvin
parent ff49103fdb
commit 04bb591ca7
3 changed files with 7 additions and 10 deletions

View File

@ -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 {

View File

@ -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;

View File

@ -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)