From mboxrd@z Thu Jan 1 00:00:00 1970 From: Segher Boessenkool Subject: Re: [cryptodev:master 130/134] aes_generic.c:undefined reference to `_restgpr_31_x' Date: Fri, 12 Jan 2018 10:39:46 -0600 Message-ID: <20180112163946.GE21977@gate.crashing.org> References: <201801122249.RHvvGQJ6%fengguang.wu@intel.com> Mime-Version: 1.0 Content-Type: text/plain; charset=us-ascii Cc: kbuild test robot , Herbert Xu , linuxppc-dev , kbuild-all@01.org, "open list:HARDWARE RANDOM NUMBER GENERATOR CORE" To: Arnd Bergmann Return-path: Received: from gate.crashing.org ([63.228.1.57]:50186 "EHLO gate.crashing.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S933994AbeALQkK (ORCPT ); Fri, 12 Jan 2018 11:40:10 -0500 Content-Disposition: inline In-Reply-To: Sender: linux-crypto-owner@vger.kernel.org List-ID: Hi! On Fri, Jan 12, 2018 at 03:55:47PM +0100, Arnd Bergmann wrote: > > crypto/aes_generic.o: In function `crypto_aes_set_key': > >>> aes_generic.c:(.text+0x4e0): undefined reference to `_restgpr_31_x' > > adding linuxpcc-dev to Cc, maybe someone knows a way out of this. > It appears related to https://gcc.gnu.org/bugzilla/show_bug.cgi?id=43810 It is not. > but I don't know what _restgpr_31_x actually does, It restores GPR31 from stack, restores LR from stack, and returns (_x is "exit"). > why it's not provided by the kernel Because the kernel refuses to use libgcc. Let's, uh, not start that again? :-) > or why the aes_generic implementation needs this on > powerpc when built with 'gcc -Os'. FWIW, the -Os change was needed > to work around a possible kernel stack overflow that can happen with > gcc-7.2, see https://patchwork.kernel.org/patch/10143607/ and > https://gcc.gnu.org/bugzilla/show_bug.cgi?id=83356 The _x versions are smaller but slower; that's why they are used with -Os. Apparently nothing else was built with -Os (and the other needed flags) before. Segher