Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S261836AbVDTXKm (ORCPT ); Wed, 20 Apr 2005 19:10:42 -0400 Received: (majordomo@vger.kernel.org) by vger.kernel.org id S261835AbVDTXKb (ORCPT ); Wed, 20 Apr 2005 19:10:31 -0400 Received: from mailfe01.swip.net ([212.247.154.1]:45000 "EHLO swip.net") by vger.kernel.org with ESMTP id S261830AbVDTXKL (ORCPT ); Wed, 20 Apr 2005 19:10:11 -0400 X-T2-Posting-ID: jLUmkBjoqvly7NM6d2gdCg== Subject: x86_64: Bug in new out of line put_user() From: Alexander Nyberg To: ak@suse.de Cc: linux-kernel@vger.kernel.org, akpm@osdl.org, nicolas@boichat.ch Content-Type: text/plain Date: Thu, 21 Apr 2005 01:10:09 +0200 Message-Id: <1114038609.500.2.camel@localhost.localdomain> Mime-Version: 1.0 X-Mailer: Evolution 2.0.4 Content-Transfer-Encoding: 7bit Sender: linux-kernel-owner@vger.kernel.org X-Mailing-List: linux-kernel@vger.kernel.org Content-Length: 2182 Lines: 92 The new out of line put_user() assembly on x86_64 changes %rcx without telling GCC about it causing things like: http://bugme.osdl.org/show_bug.cgi?id=4515 See to it that %rcx is not changed (made it consistent with get_user()). Signed-off-by: Alexander Nyberg Index: test/arch/x86_64/lib/getuser.S =================================================================== --- test.orig/arch/x86_64/lib/getuser.S 2005-04-20 23:55:35.000000000 +0200 +++ test/arch/x86_64/lib/getuser.S 2005-04-21 00:54:16.000000000 +0200 @@ -78,9 +78,9 @@ __get_user_8: GET_THREAD_INFO(%r8) addq $7,%rcx - jc bad_get_user + jc 40f cmpq threadinfo_addr_limit(%r8),%rcx - jae bad_get_user + jae 40f subq $7,%rcx 4: movq (%rcx),%rdx xorl %eax,%eax Index: test/arch/x86_64/lib/putuser.S =================================================================== --- test.orig/arch/x86_64/lib/putuser.S 2005-04-21 00:50:24.000000000 +0200 +++ test/arch/x86_64/lib/putuser.S 2005-04-21 01:02:15.000000000 +0200 @@ -46,36 +46,45 @@ __put_user_2: GET_THREAD_INFO(%r8) addq $1,%rcx - jc bad_put_user + jc 20f cmpq threadinfo_addr_limit(%r8),%rcx - jae bad_put_user -2: movw %dx,-1(%rcx) + jae 20f +2: decq %rcx + movw %dx,(%rcx) xorl %eax,%eax ret +20: decq %rcx + jmp bad_put_user .p2align 4 .globl __put_user_4 __put_user_4: GET_THREAD_INFO(%r8) addq $3,%rcx - jc bad_put_user + jc 30f cmpq threadinfo_addr_limit(%r8),%rcx - jae bad_put_user -3: movl %edx,-3(%rcx) + jae 30f +3: subq $3,%rcx + movl %edx,(%rcx) xorl %eax,%eax ret +30: subq $3,%rcx + jmp bad_put_user .p2align 4 .globl __put_user_8 __put_user_8: GET_THREAD_INFO(%r8) addq $7,%rcx - jc bad_put_user + jc 40f cmpq threadinfo_addr_limit(%r8),%rcx - jae bad_put_user -4: movq %rdx,-7(%rcx) + jae 40f +4: subq $7,%rcx + movq %rdx,(%rcx) xorl %eax,%eax ret +40: subq $7,%rcx + jmp bad_put_user bad_put_user: movq $(-EFAULT),%rax - To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to majordomo@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/