On Wed, May 08, 2019 at 09:49:03AM +0200, Peter Zijlstra wrote: > 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@xxxxxxxxxxxxx> > --- > 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_FRAME_POINTER > +#define ENCODE_FRAME_POINTER \ > + " movl %esp, %ebp\n" \ > + " andl $0x7fffffff, %ebp\n" > +#else > +#define ENCODE_FRAME_POINTER > +#endif We should put these macros in a header file somewhere (including stringified versions). -- Josh
