From mboxrd@z Thu Jan 1 00:00:00 1970 From: Greg Kroah-Hartman Subject: [PATCH 4.4 014/137] compiler-gcc: disable -ftracer for __noclone functions Date: Mon, 18 Apr 2016 11:27:56 +0900 Message-ID: <20160418022508.279439144@linuxfoundation.org> References: <20160418022507.236379264@linuxfoundation.org> Mime-Version: 1.0 Content-Type: text/plain; charset=ISO-8859-15 Cc: Greg Kroah-Hartman , stable@vger.kernel.org, Andrew Morton , Michal Marek , kvm@vger.kernel.org, Linda Walsh , Paolo Bonzini To: linux-kernel@vger.kernel.org Return-path: In-Reply-To: <20160418022507.236379264@linuxfoundation.org> Sender: linux-kernel-owner@vger.kernel.org List-Id: kvm.vger.kernel.org 4.4-stable review patch. If anyone has any objections, please let me know. ------------------ From: Paolo Bonzini commit 95272c29378ee7dc15f43fa2758cb28a5913a06d upstream. -ftracer can duplicate asm blocks causing compilation to fail in noclone functions. For example, KVM declares a global variable in an asm like asm("2: ... \n .pushsection data \n .global vmx_return \n vmx_return: .long 2b"); and -ftracer causes a double declaration. Cc: Andrew Morton Cc: Michal Marek Cc: kvm@vger.kernel.org Reported-by: Linda Walsh Signed-off-by: Paolo Bonzini Signed-off-by: Greg Kroah-Hartman --- include/linux/compiler-gcc.h | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-) --- a/include/linux/compiler-gcc.h +++ b/include/linux/compiler-gcc.h @@ -199,7 +199,7 @@ #define unreachable() __builtin_unreachable() /* Mark a function definition as prohibited from being cloned. */ -#define __noclone __attribute__((__noclone__)) +#define __noclone __attribute__((__noclone__, __optimize__("no-tracer"))) #endif /* GCC_VERSION >= 40500 */