linux/arch/x86/include/asm/unwind.h
Josh Poimboeuf 6bcdf9d51b x86/unwind: Read stack return address in update_stack_state()
Instead of reading the return address when unwind_get_return_address()
is called, read it from update_stack_state() and store it in the unwind
state.  This enables the next patch to check the return address from
unwind_next_frame() so it can detect an entry code frame.

Signed-off-by: Josh Poimboeuf <jpoimboe@redhat.com>
Acked-by: Thomas Gleixner <tglx@linutronix.de>
Cc: Andy Lutomirski <luto@kernel.org>
Cc: Borislav Petkov <bp@alien8.de>
Cc: Brian Gerst <brgerst@gmail.com>
Cc: Daniel Borkmann <daniel@iogearbox.net>
Cc: Dave Jones <davej@codemonkey.org.uk>
Cc: Denys Vlasenko <dvlasenk@redhat.com>
Cc: H. Peter Anvin <hpa@zytor.com>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Link: http://lkml.kernel.org/r/af0c5e4560c49c0343dca486ea26c4fa92bc4e35.1492020577.git.jpoimboe@redhat.com
Signed-off-by: Ingo Molnar <mingo@kernel.org>
2017-04-14 10:19:59 +02:00

79 lines
1.7 KiB
C

#ifndef _ASM_X86_UNWIND_H
#define _ASM_X86_UNWIND_H
#include <linux/sched.h>
#include <linux/ftrace.h>
#include <asm/ptrace.h>
#include <asm/stacktrace.h>
struct unwind_state {
struct stack_info stack_info;
unsigned long stack_mask;
struct task_struct *task;
int graph_idx;
#ifdef CONFIG_FRAME_POINTER
unsigned long *bp, *orig_sp;
struct pt_regs *regs;
unsigned long ip;
#else
unsigned long *sp;
#endif
};
void __unwind_start(struct unwind_state *state, struct task_struct *task,
struct pt_regs *regs, unsigned long *first_frame);
bool unwind_next_frame(struct unwind_state *state);
unsigned long unwind_get_return_address(struct unwind_state *state);
static inline bool unwind_done(struct unwind_state *state)
{
return state->stack_info.type == STACK_TYPE_UNKNOWN;
}
static inline
void unwind_start(struct unwind_state *state, struct task_struct *task,
struct pt_regs *regs, unsigned long *first_frame)
{
first_frame = first_frame ? : get_stack_pointer(task, regs);
__unwind_start(state, task, regs, first_frame);
}
#ifdef CONFIG_FRAME_POINTER
static inline
unsigned long *unwind_get_return_address_ptr(struct unwind_state *state)
{
if (unwind_done(state))
return NULL;
return state->regs ? &state->regs->ip : state->bp + 1;
}
static inline struct pt_regs *unwind_get_entry_regs(struct unwind_state *state)
{
if (unwind_done(state))
return NULL;
return state->regs;
}
#else /* !CONFIG_FRAME_POINTER */
static inline
unsigned long *unwind_get_return_address_ptr(struct unwind_state *state)
{
return NULL;
}
static inline struct pt_regs *unwind_get_entry_regs(struct unwind_state *state)
{
return NULL;
}
#endif /* CONFIG_FRAME_POINTER */
#endif /* _ASM_X86_UNWIND_H */