The kprobe trampolines have a FRAME_POINTER annotation that makes no sense. It marks the frame in the middle of pt_regs, at the place of saving BP.
Change it to mark the pt_regs frame as per the ENCODE_FRAME_POINTER from the respective entry_*.S.
Signed-off-by: Peter Zijlstra (Intel) peterz@infradead.org --- arch/x86/kernel/kprobes/common.h | 32 +++++++++++++++++++++++--------- 1 file changed, 23 insertions(+), 9 deletions(-)
--- a/arch/x86/kernel/kprobes/common.h +++ b/arch/x86/kernel/kprobes/common.h @@ -6,14 +6,15 @@
#include <asm/asm.h>
+#ifdef CONFIG_X86_64 + #ifdef CONFIG_FRAME_POINTER -# define SAVE_RBP_STRING " push %" _ASM_BP "\n" \ - " mov %" _ASM_SP ", %" _ASM_BP "\n" +#define ENCODE_FRAME_POINTER \ + " leaq 1(%rsp), %rbp\n" #else -# define SAVE_RBP_STRING " push %" _ASM_BP "\n" +#define ENCODE_FRAME_POINTER #endif
-#ifdef CONFIG_X86_64 #define SAVE_REGS_STRING \ /* Skip cs, ip, orig_ax. */ \ " subq $24, %rsp\n" \ @@ -27,11 +28,13 @@ " pushq %r10\n" \ " pushq %r11\n" \ " pushq %rbx\n" \ - SAVE_RBP_STRING \ + " pushq %rbp\n" \ " pushq %r12\n" \ " pushq %r13\n" \ " pushq %r14\n" \ - " pushq %r15\n" + " pushq %r15\n" \ + ENCODE_FRAME_POINTER + #define RESTORE_REGS_STRING \ " popq %r15\n" \ " popq %r14\n" \ @@ -51,19 +54,30 @@ /* Skip orig_ax, ip, cs */ \ " addq $24, %rsp\n" #else + +#ifdef CONFIG_FRAME_POINTER +#define ENCODE_FRAME_POINTER \ + " movl %esp, %ebp\n" \ + " andl $0x7fffffff, %ebp\n" +#else +#define ENCODE_FRAME_POINTER +#endif + #define SAVE_REGS_STRING \ /* Skip cs, ip, orig_ax and gs. */ \ - " subl $16, %esp\n" \ + " subl $4*4, %esp\n" \ " pushl %fs\n" \ " pushl %es\n" \ " pushl %ds\n" \ " pushl %eax\n" \ - SAVE_RBP_STRING \ + " pushl %ebp\n" \ " pushl %edi\n" \ " pushl %esi\n" \ " pushl %edx\n" \ " pushl %ecx\n" \ - " pushl %ebx\n" + " pushl %ebx\n" \ + ENCODE_FRAME_POINTER + #define RESTORE_REGS_STRING \ " popl %ebx\n" \ " popl %ecx\n" \