x86/stackframe/32: Allow int3_emulate_push()

Now that x86_32 has an unconditional gap on the kernel stack frame,
the int3_emulate_push() thing will work without further changes.

Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Signed-off-by: Ingo Molnar <mingo@kernel.org>

diff --git a/arch/x86/include/asm/text-patching.h b/arch/x86/include/asm/text-patching.h
index 880b551..ebf185f 100644 (file)
--- a/arch/x86/include/asm/text-patching.h
+++ b/arch/x86/include/asm/text-patching.h
@@ -51,7 +51,6 @@ static inline void int3_emulate_jmp(struct pt_regs *regs, unsigned long ip)
 #define INT3_INSN_SIZE 1
 #define CALL_INSN_SIZE 5
 
-#ifdef CONFIG_X86_64
 static inline void int3_emulate_push(struct pt_regs *regs, unsigned long val)
 {
        /*
@@ -69,7 +68,6 @@ static inline void int3_emulate_call(struct pt_regs *regs, unsigned long func)
        int3_emulate_push(regs, regs->ip - INT3_INSN_SIZE + CALL_INSN_SIZE);
        int3_emulate_jmp(regs, func);
 }
-#endif /* CONFIG_X86_64 */
 #endif /* !CONFIG_UML_X86 */
 
 #endif /* _ASM_X86_TEXT_PATCHING_H */

diff --git a/arch/x86/kernel/ftrace.c b/arch/x86/kernel/ftrace.c
index 0927bb1..a4eea7b 100644 (file)
--- a/arch/x86/kernel/ftrace.c
+++ b/arch/x86/kernel/ftrace.c
@@ -300,7 +300,6 @@ int ftrace_int3_handler(struct pt_regs *regs)
 
        ip = regs->ip - INT3_INSN_SIZE;
 
-#ifdef CONFIG_X86_64
        if (ftrace_location(ip)) {
                int3_emulate_call(regs, (unsigned long)ftrace_regs_caller);
                return 1;
@@ -312,12 +311,6 @@ int ftrace_int3_handler(struct pt_regs *regs)
                int3_emulate_call(regs, ftrace_update_func_call);
                return 1;
        }
-#else
-       if (ftrace_location(ip) || is_ftrace_caller(ip)) {
-               int3_emulate_jmp(regs, ip + CALL_INSN_SIZE);
-               return 1;
-       }
-#endif
 
        return 0;
 }