From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: from gate.crashing.org (gate.crashing.org [63.228.1.57]) (using TLSv1 with cipher DHE-RSA-AES256-SHA (256/256 bits)) (No client certificate requested) by lists.ozlabs.org (Postfix) with ESMTPS id 3tzPNf5QFWzDqNL for ; Thu, 12 Jan 2017 09:54:58 +1100 (AEDT) Date: Wed, 11 Jan 2017 16:54:41 -0600 From: Segher Boessenkool To: Christophe LEROY Cc: Christian Kujau , Benjamin Herrenschmidt , linuxppc-dev@lists.ozlabs.org Subject: Re: bootx_init.c:88: undefined reference to `__stack_chk_fail_local' Message-ID: <20170111225440.GQ28613@gate.crashing.org> References: <81ef821b-8af2-0ee5-ab35-58639548dab7@c-s.fr> Mime-Version: 1.0 Content-Type: text/plain; charset=us-ascii In-Reply-To: List-Id: Linux on PowerPC Developers Mail List List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , On Tue, Jan 10, 2017 at 07:26:15AM +0100, Christophe LEROY wrote: > >Maybe ppc32 is not supposed to be built with CC_STACKPROTECTOR ? > > Indeed, the latest versions of GCC don't use anymore the global variable > __stack_chk_guard as canary value, but a value stored at -0x7008(r2). > This is not compatible with the current implementation of the kernel > with uses r2 as a pointeur to current task struct. > So until we fix it, I don't think CC_STACKPROTECTOR is usable on PPC > with modern versions of GCC. I still wonder what changed. Nothing relevant has changed for ten years or whatever as far as I see; unless it is just the -fstack-protector-strong that makes it fail now. Curious. Segher