diff options
Diffstat (limited to 'arch/x86/kernel/ftrace_64.S')
| -rw-r--r-- | arch/x86/kernel/ftrace_64.S | 28 |
1 files changed, 24 insertions, 4 deletions
diff --git a/arch/x86/kernel/ftrace_64.S b/arch/x86/kernel/ftrace_64.S index 11ac028e30e4..4ec13608d3c6 100644 --- a/arch/x86/kernel/ftrace_64.S +++ b/arch/x86/kernel/ftrace_64.S @@ -145,6 +145,7 @@ SYM_FUNC_START(ftrace_caller) movq %rcx, RSP(%rsp) SYM_INNER_LABEL(ftrace_caller_op_ptr, SYM_L_GLOBAL) + ANNOTATE_NOENDBR /* Load the ftrace_ops into the 3rd parameter */ movq function_trace_op(%rip), %rdx @@ -155,6 +156,7 @@ SYM_INNER_LABEL(ftrace_caller_op_ptr, SYM_L_GLOBAL) movq $0, CS(%rsp) SYM_INNER_LABEL(ftrace_call, SYM_L_GLOBAL) + ANNOTATE_NOENDBR call ftrace_stub /* Handlers can change the RIP */ @@ -169,6 +171,7 @@ SYM_INNER_LABEL(ftrace_call, SYM_L_GLOBAL) * layout here. */ SYM_INNER_LABEL(ftrace_caller_end, SYM_L_GLOBAL) + ANNOTATE_NOENDBR jmp ftrace_epilogue SYM_FUNC_END(ftrace_caller); @@ -176,10 +179,10 @@ SYM_FUNC_END(ftrace_caller); SYM_FUNC_START(ftrace_epilogue) /* * This is weak to keep gas from relaxing the jumps. - * It is also used to copy the RET for trampolines. */ SYM_INNER_LABEL_ALIGN(ftrace_stub, SYM_L_WEAK) UNWIND_HINT_FUNC + ENDBR RET SYM_FUNC_END(ftrace_epilogue) @@ -192,6 +195,7 @@ SYM_FUNC_START(ftrace_regs_caller) /* save_mcount_regs fills in first two parameters */ SYM_INNER_LABEL(ftrace_regs_caller_op_ptr, SYM_L_GLOBAL) + ANNOTATE_NOENDBR /* Load the ftrace_ops into the 3rd parameter */ movq function_trace_op(%rip), %rdx @@ -221,6 +225,7 @@ SYM_INNER_LABEL(ftrace_regs_caller_op_ptr, SYM_L_GLOBAL) leaq (%rsp), %rcx SYM_INNER_LABEL(ftrace_regs_call, SYM_L_GLOBAL) + ANNOTATE_NOENDBR call ftrace_stub /* Copy flags back to SS, to restore them */ @@ -248,6 +253,7 @@ SYM_INNER_LABEL(ftrace_regs_call, SYM_L_GLOBAL) */ testq %rax, %rax SYM_INNER_LABEL(ftrace_regs_caller_jmp, SYM_L_GLOBAL) + ANNOTATE_NOENDBR jnz 1f restore_mcount_regs @@ -261,6 +267,7 @@ SYM_INNER_LABEL(ftrace_regs_caller_jmp, SYM_L_GLOBAL) * to the return. */ SYM_INNER_LABEL(ftrace_regs_caller_end, SYM_L_GLOBAL) + ANNOTATE_NOENDBR jmp ftrace_epilogue /* Swap the flags with orig_rax */ @@ -284,6 +291,7 @@ SYM_FUNC_START(__fentry__) jnz trace SYM_INNER_LABEL(ftrace_stub, SYM_L_GLOBAL) + ENDBR RET trace: @@ -307,7 +315,7 @@ EXPORT_SYMBOL(__fentry__) #ifdef CONFIG_FUNCTION_GRAPH_TRACER SYM_FUNC_START(return_to_handler) - subq $24, %rsp + subq $16, %rsp /* Save the return values */ movq %rax, (%rsp) @@ -319,7 +327,19 @@ SYM_FUNC_START(return_to_handler) movq %rax, %rdi movq 8(%rsp), %rdx movq (%rsp), %rax - addq $24, %rsp - JMP_NOSPEC rdi + + addq $16, %rsp + /* + * Jump back to the old return address. This cannot be JMP_NOSPEC rdi + * since IBT would demand that contain ENDBR, which simply isn't so for + * return addresses. Use a retpoline here to keep the RSB balanced. + */ + ANNOTATE_INTRA_FUNCTION_CALL + call .Ldo_rop + int3 +.Ldo_rop: + mov %rdi, (%rsp) + UNWIND_HINT_FUNC + RET SYM_FUNC_END(return_to_handler) #endif |