From cb7390fed4c04e609a420ac0b1c07a7a781b43bf Mon Sep 17 00:00:00 2001 From: Josh Poimboeuf Date: Fri, 22 Jan 2016 10:16:12 -0600 Subject: [PATCH] x86/kvm: Make test_cc() always inline With some configs (including allyesconfig), gcc doesn't inline test_cc(). When that happens, test_cc() doesn't create a stack frame before inserting the inline asm call instruction. This breaks frame pointer convention if CONFIG_FRAME_POINTER is enabled and can result in a bad stack trace. Force it to always be inlined so that its containing function's stack frame can be used. Suggested-by: Paolo Bonzini Signed-off-by: Josh Poimboeuf Acked-by: Paolo Bonzini Cc: Andrew Morton Cc: Andy Lutomirski Cc: Andy Lutomirski Cc: Arnaldo Carvalho de Melo Cc: Bernd Petrovitsch Cc: Borislav Petkov Cc: Brian Gerst Cc: Chris J Arges Cc: Denys Vlasenko Cc: Gleb Natapov Cc: H. Peter Anvin Cc: Jiri Slaby Cc: Linus Torvalds Cc: Michal Marek Cc: Namhyung Kim Cc: Pedro Alves Cc: Peter Zijlstra Cc: Thomas Gleixner Cc: kvm@vger.kernel.org Cc: live-patching@vger.kernel.org Link: http://lkml.kernel.org/r/20160122161612.GE20502@treble.redhat.com Signed-off-by: Ingo Molnar --- arch/x86/kvm/emulate.c | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-) diff --git a/arch/x86/kvm/emulate.c b/arch/x86/kvm/emulate.c index aa4d72667878..80363ebfd0a6 100644 --- a/arch/x86/kvm/emulate.c +++ b/arch/x86/kvm/emulate.c @@ -969,7 +969,7 @@ static int em_bsr_c(struct x86_emulate_ctxt *ctxt) return fastop(ctxt, em_bsr); } -static u8 test_cc(unsigned int condition, unsigned long flags) +static __always_inline u8 test_cc(unsigned int condition, unsigned long flags) { u8 rc; void (*fop)(void) = (void *)em_setcc + 4 * (condition & 0xf);