From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1755877Ab2BATEh (ORCPT ); Wed, 1 Feb 2012 14:04:37 -0500 Received: from e9.ny.us.ibm.com ([32.97.182.139]:44210 "EHLO e9.ny.us.ibm.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1755635Ab2BATEe (ORCPT ); Wed, 1 Feb 2012 14:04:34 -0500 Message-ID: <1328123041.4764.20.camel@otta> Subject: Re: Memory corruption due to word sharing From: Peter Bergner To: David Miller Cc: matz@suse.de, jkosina@suse.cz, torvalds@linux-foundation.org, walters@verbum.org, jack@suse.cz, linux-kernel@vger.kernel.org, linux-ia64@vger.kernel.org, dsterba@suse.cz, ptesarik@suse.cz, rguenther@suse.de, gcc@gcc.gnu.org Date: Wed, 01 Feb 2012 13:04:01 -0600 In-Reply-To: <20120201.130905.1131458895704793597.davem@davemloft.net> References: <20120201.130905.1131458895704793597.davem@davemloft.net> Content-Type: text/plain; charset="UTF-8" X-Mailer: Evolution 3.2.2- Content-Transfer-Encoding: 7bit Mime-Version: 1.0 X-Content-Scanned: Fidelis XPS MAILER x-cbid: 12020119-7182-0000-0000-000000A2DDCB Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On Wed, 2012-02-01 at 13:09 -0500, David Miller wrote: > From: Michael Matz > Date: Wed, 1 Feb 2012 18:41:05 +0100 (CET) > > > One problem is that it's not a new problem, GCC emitted similar code since > > about forever, and still they turned up only now (well, probably because > > ia64 is dead, but sparc64 should have similar problems). > > Indeed, on sparc64 it does do the silly 64-bit access too: > > wrong: > ldx [%o0+8], %g2 > sethi %hi(2147483648), %g1 > or %g2, %g1, %g1 > jmp %o7+8 > stx %g1, [%o0+8] Ditto for powerpc64-linux: ld 9,8(3) li 10,1 rldimi 9,10,31,32 std 9,8(3) blr Peter