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| author | Peter Zijlstra <peterz@infradead.org> | 2022-09-15 13:11:35 +0200 |
|---|---|---|
| committer | Peter Zijlstra <peterz@infradead.org> | 2022-10-17 16:41:18 +0200 |
| commit | eac828eaef295cd0cc8b58f55fa5c8401fdc2370 (patch) | |
| tree | 6fe1ce228938debd23aea644f731f1505caa8152 /arch/x86/kernel | |
| parent | x86/bpf: Emit call depth accounting if required (diff) | |
| download | linux-eac828eaef295cd0cc8b58f55fa5c8401fdc2370.tar.xz linux-eac828eaef295cd0cc8b58f55fa5c8401fdc2370.zip | |
x86/ftrace: Remove ftrace_epilogue()
Remove the weird jumps to RET and simply use RET.
This then promotes ftrace_stub() to a real function; which becomes
important for kcfi.
Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Link: https://lore.kernel.org/r/20220915111148.719080593@infradead.org
Diffstat (limited to 'arch/x86/kernel')
| -rw-r--r-- | arch/x86/kernel/ftrace_64.S | 21 |
1 files changed, 6 insertions, 15 deletions
diff --git a/arch/x86/kernel/ftrace_64.S b/arch/x86/kernel/ftrace_64.S index dfeb227de561..a90c55a6b481 100644 --- a/arch/x86/kernel/ftrace_64.S +++ b/arch/x86/kernel/ftrace_64.S @@ -172,20 +172,14 @@ SYM_INNER_LABEL(ftrace_call, SYM_L_GLOBAL) */ SYM_INNER_LABEL(ftrace_caller_end, SYM_L_GLOBAL) ANNOTATE_NOENDBR - - jmp ftrace_epilogue + RET SYM_FUNC_END(ftrace_caller); STACK_FRAME_NON_STANDARD_FP(ftrace_caller) -SYM_FUNC_START(ftrace_epilogue) -/* - * This is weak to keep gas from relaxing the jumps. - */ -SYM_INNER_LABEL_ALIGN(ftrace_stub, SYM_L_WEAK) +SYM_FUNC_START(ftrace_stub) UNWIND_HINT_FUNC - ENDBR RET -SYM_FUNC_END(ftrace_epilogue) +SYM_FUNC_END(ftrace_stub) SYM_FUNC_START(ftrace_regs_caller) /* Save the current flags before any operations that can change them */ @@ -262,14 +256,11 @@ SYM_INNER_LABEL(ftrace_regs_caller_jmp, SYM_L_GLOBAL) popfq /* - * As this jmp to ftrace_epilogue can be a short jump - * it must not be copied into the trampoline. - * The trampoline will add the code to jump - * to the return. + * The trampoline will add the return. */ SYM_INNER_LABEL(ftrace_regs_caller_end, SYM_L_GLOBAL) ANNOTATE_NOENDBR - jmp ftrace_epilogue + RET /* Swap the flags with orig_rax */ 1: movq MCOUNT_REG_SIZE(%rsp), %rdi @@ -280,7 +271,7 @@ SYM_INNER_LABEL(ftrace_regs_caller_end, SYM_L_GLOBAL) /* Restore flags */ popfq UNWIND_HINT_FUNC - jmp ftrace_epilogue + RET SYM_FUNC_END(ftrace_regs_caller) STACK_FRAME_NON_STANDARD_FP(ftrace_regs_caller) |