From patchwork Fri Jul 17 16:53:22 2020 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Ilya Leoshkevich X-Patchwork-Id: 1331339 X-Patchwork-Delegate: bpf@iogearbox.net Return-Path: X-Original-To: incoming-bpf@patchwork.ozlabs.org Delivered-To: patchwork-incoming-bpf@bilbo.ozlabs.org Authentication-Results: ozlabs.org; spf=pass (sender SPF authorized) smtp.mailfrom=vger.kernel.org (client-ip=23.128.96.18; helo=vger.kernel.org; envelope-from=bpf-owner@vger.kernel.org; receiver=) Authentication-Results: ozlabs.org; dmarc=fail (p=none dis=none) header.from=linux.ibm.com Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by ozlabs.org (Postfix) with ESMTP id 4B7cfj39g9z9sR4 for ; Sat, 18 Jul 2020 02:54:37 +1000 (AEST) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1726775AbgGQQyg (ORCPT ); Fri, 17 Jul 2020 12:54:36 -0400 Received: from mx0b-001b2d01.pphosted.com ([148.163.158.5]:44174 "EHLO mx0a-001b2d01.pphosted.com" rhost-flags-OK-OK-OK-FAIL) by vger.kernel.org with ESMTP id S1726687AbgGQQyg (ORCPT ); Fri, 17 Jul 2020 12:54:36 -0400 Received: from pps.filterd (m0098419.ppops.net [127.0.0.1]) by mx0b-001b2d01.pphosted.com (8.16.0.42/8.16.0.42) with SMTP id 06HGWRxl049095; Fri, 17 Jul 2020 12:54:23 -0400 Received: from ppma06ams.nl.ibm.com (66.31.33a9.ip4.static.sl-reverse.com [169.51.49.102]) by mx0b-001b2d01.pphosted.com with ESMTP id 32as6epf43-1 (version=TLSv1.2 cipher=ECDHE-RSA-AES256-GCM-SHA384 bits=256 verify=NOT); Fri, 17 Jul 2020 12:54:23 -0400 Received: from pps.filterd (ppma06ams.nl.ibm.com [127.0.0.1]) by ppma06ams.nl.ibm.com (8.16.0.42/8.16.0.42) with SMTP id 06HGpjeI014515; Fri, 17 Jul 2020 16:54:22 GMT Received: from b06cxnps4075.portsmouth.uk.ibm.com (d06relay12.portsmouth.uk.ibm.com [9.149.109.197]) by ppma06ams.nl.ibm.com with ESMTP id 3274pgxpp6-1 (version=TLSv1.2 cipher=ECDHE-RSA-AES256-GCM-SHA384 bits=256 verify=NOT); Fri, 17 Jul 2020 16:54:21 +0000 Received: from b06wcsmtp001.portsmouth.uk.ibm.com (b06wcsmtp001.portsmouth.uk.ibm.com [9.149.105.160]) by b06cxnps4075.portsmouth.uk.ibm.com (8.14.9/8.14.9/NCO v10.0) with ESMTP id 06HGsJNw3211740 (version=TLSv1/SSLv3 cipher=DHE-RSA-AES256-GCM-SHA384 bits=256 verify=OK); Fri, 17 Jul 2020 16:54:19 GMT Received: from b06wcsmtp001.portsmouth.uk.ibm.com (unknown [127.0.0.1]) by IMSVA (Postfix) with ESMTP id ECF02A4062; Fri, 17 Jul 2020 16:54:18 +0000 (GMT) Received: from b06wcsmtp001.portsmouth.uk.ibm.com (unknown [127.0.0.1]) by IMSVA (Postfix) with ESMTP id 719B4A4054; Fri, 17 Jul 2020 16:54:18 +0000 (GMT) Received: from localhost.localdomain (unknown [9.145.6.1]) by b06wcsmtp001.portsmouth.uk.ibm.com (Postfix) with ESMTP; Fri, 17 Jul 2020 16:54:18 +0000 (GMT) From: Ilya Leoshkevich To: Alexei Starovoitov , Daniel Borkmann Cc: bpf@vger.kernel.org, Heiko Carstens , Vasily Gorbik , Ilya Leoshkevich Subject: [PATCH 1/5] selftests: bpf: test_kmod.sh: fix running out of srctree Date: Fri, 17 Jul 2020 18:53:22 +0200 Message-Id: <20200717165326.6786-2-iii@linux.ibm.com> X-Mailer: git-send-email 2.25.4 In-Reply-To: <20200717165326.6786-1-iii@linux.ibm.com> References: <20200717165326.6786-1-iii@linux.ibm.com> MIME-Version: 1.0 X-TM-AS-GCONF: 00 X-Proofpoint-Virus-Version: vendor=fsecure engine=2.50.10434:6.0.235, 18.0.687 definitions=2020-07-17_08:2020-07-17,2020-07-17 signatures=0 X-Proofpoint-Spam-Details: rule=outbound_notspam policy=outbound score=0 lowpriorityscore=0 adultscore=0 clxscore=1015 suspectscore=0 mlxscore=0 bulkscore=0 malwarescore=0 priorityscore=1501 impostorscore=0 phishscore=0 spamscore=0 mlxlogscore=975 classifier=spam adjust=0 reason=mlx scancount=1 engine=8.12.0-2006250000 definitions=main-2007170115 Sender: bpf-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: bpf@vger.kernel.org When running out of srctree, relative path to lib/test_bpf.ko is different than when running in srctree. Check $building_out_of_srctree environment variable and use a different relative path if needed. Signed-off-by: Ilya Leoshkevich --- tools/testing/selftests/bpf/test_kmod.sh | 12 +++++++++--- 1 file changed, 9 insertions(+), 3 deletions(-) diff --git a/tools/testing/selftests/bpf/test_kmod.sh b/tools/testing/selftests/bpf/test_kmod.sh index 9df0d2ac45f8..4f6444bcd53f 100755 --- a/tools/testing/selftests/bpf/test_kmod.sh +++ b/tools/testing/selftests/bpf/test_kmod.sh @@ -10,7 +10,13 @@ if [ "$(id -u)" != "0" ]; then exit $ksft_skip fi -SRC_TREE=../../../../ +if [ "$building_out_of_srctree" ]; then + # We are in linux-build/kselftest/bpf + OUTPUT=../../ +else + # We are in linux/tools/testing/selftests/bpf + OUTPUT=../../../../ +fi test_run() { @@ -19,8 +25,8 @@ test_run() echo "[ JIT enabled:$1 hardened:$2 ]" dmesg -C - if [ -f ${SRC_TREE}/lib/test_bpf.ko ]; then - insmod ${SRC_TREE}/lib/test_bpf.ko 2> /dev/null + if [ -f ${OUTPUT}/lib/test_bpf.ko ]; then + insmod ${OUTPUT}/lib/test_bpf.ko 2> /dev/null if [ $? -ne 0 ]; then rc=1 fi From patchwork Fri Jul 17 16:53:23 2020 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Ilya Leoshkevich X-Patchwork-Id: 1331340 X-Patchwork-Delegate: bpf@iogearbox.net Return-Path: X-Original-To: incoming-bpf@patchwork.ozlabs.org Delivered-To: patchwork-incoming-bpf@bilbo.ozlabs.org Authentication-Results: ozlabs.org; spf=pass (sender SPF authorized) smtp.mailfrom=vger.kernel.org (client-ip=23.128.96.18; helo=vger.kernel.org; envelope-from=bpf-owner@vger.kernel.org; receiver=) Authentication-Results: ozlabs.org; dmarc=fail (p=none dis=none) header.from=linux.ibm.com Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by ozlabs.org (Postfix) with ESMTP id 4B7cgy6DfTz9sR4 for ; Sat, 18 Jul 2020 02:55:42 +1000 (AEST) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1726530AbgGQQzk (ORCPT ); Fri, 17 Jul 2020 12:55:40 -0400 Received: from mx0a-001b2d01.pphosted.com ([148.163.156.1]:63814 "EHLO mx0a-001b2d01.pphosted.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1726293AbgGQQzk (ORCPT ); Fri, 17 Jul 2020 12:55:40 -0400 Received: from pps.filterd (m0187473.ppops.net [127.0.0.1]) by mx0a-001b2d01.pphosted.com (8.16.0.42/8.16.0.42) with SMTP id 06HGZgiJ060100; Fri, 17 Jul 2020 12:55:27 -0400 Received: from ppma03fra.de.ibm.com (6b.4a.5195.ip4.static.sl-reverse.com [149.81.74.107]) by mx0a-001b2d01.pphosted.com with ESMTP id 32792yeph9-1 (version=TLSv1.2 cipher=ECDHE-RSA-AES256-GCM-SHA384 bits=256 verify=NOT); Fri, 17 Jul 2020 12:55:26 -0400 Received: from pps.filterd (ppma03fra.de.ibm.com [127.0.0.1]) by ppma03fra.de.ibm.com (8.16.0.42/8.16.0.42) with SMTP id 06HGntZm010477; Fri, 17 Jul 2020 16:55:24 GMT Received: from b06cxnps3074.portsmouth.uk.ibm.com (d06relay09.portsmouth.uk.ibm.com [9.149.109.194]) by ppma03fra.de.ibm.com with ESMTP id 327527kh09-1 (version=TLSv1.2 cipher=ECDHE-RSA-AES256-GCM-SHA384 bits=256 verify=NOT); Fri, 17 Jul 2020 16:55:24 +0000 Received: from b06wcsmtp001.portsmouth.uk.ibm.com (b06wcsmtp001.portsmouth.uk.ibm.com [9.149.105.160]) by b06cxnps3074.portsmouth.uk.ibm.com (8.14.9/8.14.9/NCO v10.0) with ESMTP id 06HGtLG331523320 (version=TLSv1/SSLv3 cipher=DHE-RSA-AES256-GCM-SHA384 bits=256 verify=OK); Fri, 17 Jul 2020 16:55:21 GMT Received: from b06wcsmtp001.portsmouth.uk.ibm.com (unknown [127.0.0.1]) by IMSVA (Postfix) with ESMTP id EF0BDA405B; Fri, 17 Jul 2020 16:55:20 +0000 (GMT) Received: from b06wcsmtp001.portsmouth.uk.ibm.com (unknown [127.0.0.1]) by IMSVA (Postfix) with ESMTP id 68A54A405F; Fri, 17 Jul 2020 16:55:20 +0000 (GMT) Received: from localhost.localdomain (unknown [9.145.6.1]) by b06wcsmtp001.portsmouth.uk.ibm.com (Postfix) with ESMTP; Fri, 17 Jul 2020 16:55:20 +0000 (GMT) From: Ilya Leoshkevich To: Alexei Starovoitov , Daniel Borkmann Cc: bpf@vger.kernel.org, Heiko Carstens , Vasily Gorbik , Ilya Leoshkevich , Seth Forshee Subject: [PATCH 2/5] s390/bpf: fix sign extension in branch_ku Date: Fri, 17 Jul 2020 18:53:23 +0200 Message-Id: <20200717165326.6786-3-iii@linux.ibm.com> X-Mailer: git-send-email 2.25.4 In-Reply-To: <20200717165326.6786-1-iii@linux.ibm.com> References: <20200717165326.6786-1-iii@linux.ibm.com> MIME-Version: 1.0 X-TM-AS-GCONF: 00 X-Proofpoint-Virus-Version: vendor=fsecure engine=2.50.10434:6.0.235, 18.0.687 definitions=2020-07-17_08:2020-07-17,2020-07-17 signatures=0 X-Proofpoint-Spam-Details: rule=outbound_notspam policy=outbound score=0 suspectscore=0 mlxlogscore=999 priorityscore=1501 lowpriorityscore=0 clxscore=1015 adultscore=0 impostorscore=0 spamscore=0 malwarescore=0 bulkscore=0 mlxscore=0 phishscore=0 classifier=spam adjust=0 reason=mlx scancount=1 engine=8.12.0-2006250000 definitions=main-2007170117 Sender: bpf-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: bpf@vger.kernel.org Both signed and unsigned variants of BPF_JMP | BPF_K require sign-extending the immediate. JIT emits cgfi for the signed case, which is correct, and clgfi for the unsigned case, which is not correct: clgfi zero-extends the immediate. s390 does not provide an instruction that does sign-extension and unsigned comparison at the same time. Therefore, fix by first loading the sign-extended immediate into work register REG_1 and proceeding as if it's BPF_X. Fixes: 4e9b4a6883dd ("s390/bpf: Use relative long branches") Reported-by: Seth Forshee Signed-off-by: Ilya Leoshkevich Tested-by: Seth Forshee --- arch/s390/net/bpf_jit_comp.c | 19 ++++--------------- 1 file changed, 4 insertions(+), 15 deletions(-) diff --git a/arch/s390/net/bpf_jit_comp.c b/arch/s390/net/bpf_jit_comp.c index 8fe7bdfc8d15..67608f6092f8 100644 --- a/arch/s390/net/bpf_jit_comp.c +++ b/arch/s390/net/bpf_jit_comp.c @@ -1507,21 +1507,10 @@ static noinline int bpf_jit_insn(struct bpf_jit *jit, struct bpf_prog *fp, } break; branch_ku: - is_jmp32 = BPF_CLASS(insn->code) == BPF_JMP32; - /* clfi or clgfi %dst,imm */ - EMIT6_IMM(is_jmp32 ? 0xc20f0000 : 0xc20e0000, - dst_reg, imm); - if (!is_first_pass(jit) && - can_use_rel(jit, addrs[i + off + 1])) { - /* brc mask,off */ - EMIT4_PCREL_RIC(0xa7040000, - mask >> 12, addrs[i + off + 1]); - } else { - /* brcl mask,off */ - EMIT6_PCREL_RILC(0xc0040000, - mask >> 12, addrs[i + off + 1]); - } - break; + /* lgfi %w1,imm (load sign extend imm) */ + src_reg = REG_1; + EMIT6_IMM(0xc0010000, src_reg, imm); + goto branch_xu; branch_xs: is_jmp32 = BPF_CLASS(insn->code) == BPF_JMP32; if (!is_first_pass(jit) && From patchwork Fri Jul 17 16:53:24 2020 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Ilya Leoshkevich X-Patchwork-Id: 1331343 X-Patchwork-Delegate: bpf@iogearbox.net Return-Path: X-Original-To: incoming-bpf@patchwork.ozlabs.org Delivered-To: patchwork-incoming-bpf@bilbo.ozlabs.org Authentication-Results: ozlabs.org; spf=pass (sender SPF authorized) smtp.mailfrom=vger.kernel.org (client-ip=23.128.96.18; helo=vger.kernel.org; envelope-from=bpf-owner@vger.kernel.org; receiver=) Authentication-Results: ozlabs.org; dmarc=fail (p=none dis=none) header.from=linux.ibm.com Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by ozlabs.org (Postfix) with ESMTP id 4B7cjz1stQz9sTF for ; Sat, 18 Jul 2020 02:57:27 +1000 (AEST) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1727828AbgGQQ50 (ORCPT ); Fri, 17 Jul 2020 12:57:26 -0400 Received: from mx0b-001b2d01.pphosted.com ([148.163.158.5]:37434 "EHLO mx0a-001b2d01.pphosted.com" rhost-flags-OK-OK-OK-FAIL) by vger.kernel.org with ESMTP id S1727870AbgGQQ5V (ORCPT ); Fri, 17 Jul 2020 12:57:21 -0400 Received: from pps.filterd (m0098414.ppops.net [127.0.0.1]) by mx0b-001b2d01.pphosted.com (8.16.0.42/8.16.0.42) with SMTP id 06HGWh21080245; Fri, 17 Jul 2020 12:57:09 -0400 Received: from ppma02fra.de.ibm.com (47.49.7a9f.ip4.static.sl-reverse.com [159.122.73.71]) by mx0b-001b2d01.pphosted.com with ESMTP id 32ax79473g-1 (version=TLSv1.2 cipher=ECDHE-RSA-AES256-GCM-SHA384 bits=256 verify=NOT); Fri, 17 Jul 2020 12:57:09 -0400 Received: from pps.filterd (ppma02fra.de.ibm.com [127.0.0.1]) by ppma02fra.de.ibm.com (8.16.0.42/8.16.0.42) with SMTP id 06HGnf6X027378; Fri, 17 Jul 2020 16:57:07 GMT Received: from b06cxnps4075.portsmouth.uk.ibm.com (d06relay12.portsmouth.uk.ibm.com [9.149.109.197]) by ppma02fra.de.ibm.com with ESMTP id 327527y40h-1 (version=TLSv1.2 cipher=ECDHE-RSA-AES256-GCM-SHA384 bits=256 verify=NOT); Fri, 17 Jul 2020 16:57:07 +0000 Received: from b06wcsmtp001.portsmouth.uk.ibm.com (b06wcsmtp001.portsmouth.uk.ibm.com [9.149.105.160]) by b06cxnps4075.portsmouth.uk.ibm.com (8.14.9/8.14.9/NCO v10.0) with ESMTP id 06HGtoE154591736 (version=TLSv1/SSLv3 cipher=DHE-RSA-AES256-GCM-SHA384 bits=256 verify=OK); Fri, 17 Jul 2020 16:55:50 GMT Received: from b06wcsmtp001.portsmouth.uk.ibm.com (unknown [127.0.0.1]) by IMSVA (Postfix) with ESMTP id 15C21A405C; Fri, 17 Jul 2020 16:55:50 +0000 (GMT) Received: from b06wcsmtp001.portsmouth.uk.ibm.com (unknown [127.0.0.1]) by IMSVA (Postfix) with ESMTP id 8E7C0A405B; Fri, 17 Jul 2020 16:55:49 +0000 (GMT) Received: from localhost.localdomain (unknown [9.145.6.1]) by b06wcsmtp001.portsmouth.uk.ibm.com (Postfix) with ESMTP; Fri, 17 Jul 2020 16:55:49 +0000 (GMT) From: Ilya Leoshkevich To: Alexei Starovoitov , Daniel Borkmann Cc: bpf@vger.kernel.org, Heiko Carstens , Vasily Gorbik , Ilya Leoshkevich Subject: [PATCH 3/5] s390/bpf: use brcl for jumping to exit_ip if necessary Date: Fri, 17 Jul 2020 18:53:24 +0200 Message-Id: <20200717165326.6786-4-iii@linux.ibm.com> X-Mailer: git-send-email 2.25.4 In-Reply-To: <20200717165326.6786-1-iii@linux.ibm.com> References: <20200717165326.6786-1-iii@linux.ibm.com> MIME-Version: 1.0 X-TM-AS-GCONF: 00 X-Proofpoint-Virus-Version: vendor=fsecure engine=2.50.10434:6.0.235, 18.0.687 definitions=2020-07-17_08:2020-07-17,2020-07-17 signatures=0 X-Proofpoint-Spam-Details: rule=outbound_notspam policy=outbound score=0 bulkscore=0 adultscore=0 spamscore=0 priorityscore=1501 mlxscore=0 mlxlogscore=865 phishscore=0 lowpriorityscore=0 clxscore=1015 malwarescore=0 suspectscore=0 impostorscore=0 classifier=spam adjust=0 reason=mlx scancount=1 engine=8.12.0-2006250000 definitions=main-2007170117 Sender: bpf-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: bpf@vger.kernel.org "BPF_MAXINSNS: Maximum possible literals" test causes panic with bpf_jit_harden = 2. The reason is that BPF_JMP | BPF_EXIT is always emitted as brc, however, after removal of JITed image size limitations, brcl might be required. Fix by using brcl when necessary. Fixes: 4e9b4a6883dd ("s390/bpf: Use relative long branches") Signed-off-by: Ilya Leoshkevich --- arch/s390/net/bpf_jit_comp.c | 8 ++++++-- 1 file changed, 6 insertions(+), 2 deletions(-) diff --git a/arch/s390/net/bpf_jit_comp.c b/arch/s390/net/bpf_jit_comp.c index 67608f6092f8..625ebe32b2d1 100644 --- a/arch/s390/net/bpf_jit_comp.c +++ b/arch/s390/net/bpf_jit_comp.c @@ -1358,8 +1358,12 @@ static noinline int bpf_jit_insn(struct bpf_jit *jit, struct bpf_prog *fp, last = (i == fp->len - 1) ? 1 : 0; if (last) break; - /* j */ - EMIT4_PCREL(0xa7f40000, jit->exit_ip - jit->prg); + if (!is_first_pass(jit) && can_use_rel(jit, jit->exit_ip)) + /* brc 0xf, */ + EMIT4_PCREL_RIC(0xa7040000, 0xf, jit->exit_ip); + else + /* brcl 0xf, */ + EMIT6_PCREL_RILC(0xc0040000, 0xf, jit->exit_ip); break; /* * Branch relative (number of skipped instructions) to offset on From patchwork Fri Jul 17 16:53:25 2020 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Ilya Leoshkevich X-Patchwork-Id: 1331342 X-Patchwork-Delegate: bpf@iogearbox.net Return-Path: X-Original-To: incoming-bpf@patchwork.ozlabs.org Delivered-To: patchwork-incoming-bpf@bilbo.ozlabs.org Authentication-Results: ozlabs.org; spf=pass (sender SPF authorized) smtp.mailfrom=vger.kernel.org (client-ip=23.128.96.18; helo=vger.kernel.org; envelope-from=bpf-owner@vger.kernel.org; receiver=) Authentication-Results: ozlabs.org; dmarc=fail (p=none dis=none) header.from=linux.ibm.com Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by ozlabs.org (Postfix) with ESMTP id 4B7cj1567Gz9sR4 for ; Sat, 18 Jul 2020 02:56:37 +1000 (AEST) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1728042AbgGQQ4g (ORCPT ); Fri, 17 Jul 2020 12:56:36 -0400 Received: from mx0a-001b2d01.pphosted.com ([148.163.156.1]:6284 "EHLO mx0a-001b2d01.pphosted.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1728031AbgGQQ4f (ORCPT ); Fri, 17 Jul 2020 12:56:35 -0400 Received: from pps.filterd (m0098409.ppops.net [127.0.0.1]) by mx0a-001b2d01.pphosted.com (8.16.0.42/8.16.0.42) with SMTP id 06HGXd1a056699; Fri, 17 Jul 2020 12:56:23 -0400 Received: from ppma03fra.de.ibm.com (6b.4a.5195.ip4.static.sl-reverse.com [149.81.74.107]) by mx0a-001b2d01.pphosted.com with ESMTP id 32autbh9wy-1 (version=TLSv1.2 cipher=ECDHE-RSA-AES256-GCM-SHA384 bits=256 verify=NOT); Fri, 17 Jul 2020 12:56:23 -0400 Received: from pps.filterd (ppma03fra.de.ibm.com [127.0.0.1]) by ppma03fra.de.ibm.com (8.16.0.42/8.16.0.42) with SMTP id 06HGoLqm010926; Fri, 17 Jul 2020 16:56:21 GMT Received: from b06cxnps4075.portsmouth.uk.ibm.com (d06relay12.portsmouth.uk.ibm.com [9.149.109.197]) by ppma03fra.de.ibm.com with ESMTP id 327527kh0r-1 (version=TLSv1.2 cipher=ECDHE-RSA-AES256-GCM-SHA384 bits=256 verify=NOT); Fri, 17 Jul 2020 16:56:21 +0000 Received: from b06wcsmtp001.portsmouth.uk.ibm.com (b06wcsmtp001.portsmouth.uk.ibm.com [9.149.105.160]) by b06cxnps4075.portsmouth.uk.ibm.com (8.14.9/8.14.9/NCO v10.0) with ESMTP id 06HGuIHc61407314 (version=TLSv1/SSLv3 cipher=DHE-RSA-AES256-GCM-SHA384 bits=256 verify=OK); Fri, 17 Jul 2020 16:56:18 GMT Received: from b06wcsmtp001.portsmouth.uk.ibm.com (unknown [127.0.0.1]) by IMSVA (Postfix) with ESMTP id 69675A405F; Fri, 17 Jul 2020 16:56:18 +0000 (GMT) Received: from b06wcsmtp001.portsmouth.uk.ibm.com (unknown [127.0.0.1]) by IMSVA (Postfix) with ESMTP id EDF72A405B; Fri, 17 Jul 2020 16:56:17 +0000 (GMT) Received: from localhost.localdomain (unknown [9.145.6.1]) by b06wcsmtp001.portsmouth.uk.ibm.com (Postfix) with ESMTP; Fri, 17 Jul 2020 16:56:17 +0000 (GMT) From: Ilya Leoshkevich To: Alexei Starovoitov , Daniel Borkmann Cc: bpf@vger.kernel.org, Heiko Carstens , Vasily Gorbik , Ilya Leoshkevich Subject: [PATCH 4/5] s390/bpf: tolerate not converging code shrinking Date: Fri, 17 Jul 2020 18:53:25 +0200 Message-Id: <20200717165326.6786-5-iii@linux.ibm.com> X-Mailer: git-send-email 2.25.4 In-Reply-To: <20200717165326.6786-1-iii@linux.ibm.com> References: <20200717165326.6786-1-iii@linux.ibm.com> MIME-Version: 1.0 X-TM-AS-GCONF: 00 X-Proofpoint-Virus-Version: vendor=fsecure engine=2.50.10434:6.0.235, 18.0.687 definitions=2020-07-17_08:2020-07-17,2020-07-17 signatures=0 X-Proofpoint-Spam-Details: rule=outbound_notspam policy=outbound score=0 spamscore=0 priorityscore=1501 suspectscore=0 mlxscore=0 phishscore=0 bulkscore=0 impostorscore=0 mlxlogscore=999 clxscore=1015 lowpriorityscore=0 malwarescore=0 adultscore=0 classifier=spam adjust=0 reason=mlx scancount=1 engine=8.12.0-2006250000 definitions=main-2007170117 Sender: bpf-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: bpf@vger.kernel.org "BPF_MAXINSNS: Maximum possible literals" unnecessarily falls back to the interpreter because of failing sanity check in bpf_set_addr. The problem is that there are a lot of branches that can be shrunk, and doing so opens up the possibility to shrink even more. This process does not converge after 3 passes, causing code offsets to change during the codegen pass, which must never happen. Fix by inserting nops during codegen pass in order to preserve code offets. Fixes: 4e9b4a6883dd ("s390/bpf: Use relative long branches") Signed-off-by: Ilya Leoshkevich --- arch/s390/net/bpf_jit_comp.c | 27 ++++++++++++++++++++++++++- 1 file changed, 26 insertions(+), 1 deletion(-) diff --git a/arch/s390/net/bpf_jit_comp.c b/arch/s390/net/bpf_jit_comp.c index 625ebe32b2d1..e68854ab27ae 100644 --- a/arch/s390/net/bpf_jit_comp.c +++ b/arch/s390/net/bpf_jit_comp.c @@ -490,6 +490,24 @@ static void save_restore_regs(struct bpf_jit *jit, int op, u32 stack_depth) } while (re <= last); } +static void bpf_skip(struct bpf_jit *jit, int size) +{ + if (size >= 6 && !is_valid_rel(size)) { + /* brcl 0xf,size */ + EMIT6_PCREL_RIL(0xc0f4000000, size); + size -= 6; + } else if (size >= 4 && is_valid_rel(size)) { + /* brc 0xf,size */ + EMIT4_PCREL(0xa7f40000, size); + size -= 4; + } + while (size >= 2) { + /* bcr 0,%0 */ + _EMIT2(0x0700); + size -= 2; + } +} + /* * Emit function prologue * @@ -1610,7 +1628,14 @@ static bool bpf_is_new_addr_sane(struct bpf_jit *jit, int i) */ static int bpf_set_addr(struct bpf_jit *jit, int i) { - if (!bpf_is_new_addr_sane(jit, i)) + int delta; + + if (is_codegen_pass(jit)) { + delta = jit->prg - jit->addrs[i]; + if (delta < 0) + bpf_skip(jit, -delta); + } + if (WARN_ON_ONCE(!bpf_is_new_addr_sane(jit, i))) return -1; jit->addrs[i] = jit->prg; return 0; From patchwork Fri Jul 17 16:53:26 2020 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Ilya Leoshkevich X-Patchwork-Id: 1331344 X-Patchwork-Delegate: bpf@iogearbox.net Return-Path: X-Original-To: incoming-bpf@patchwork.ozlabs.org Delivered-To: patchwork-incoming-bpf@bilbo.ozlabs.org Authentication-Results: ozlabs.org; spf=pass (sender SPF authorized) smtp.mailfrom=vger.kernel.org (client-ip=23.128.96.18; helo=vger.kernel.org; envelope-from=bpf-owner@vger.kernel.org; receiver=) Authentication-Results: ozlabs.org; dmarc=fail (p=none dis=none) header.from=linux.ibm.com Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by ozlabs.org (Postfix) with ESMTP id 4B7ckH4dw9z9sR4 for ; Sat, 18 Jul 2020 02:57:43 +1000 (AEST) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1728209AbgGQQ5m (ORCPT ); Fri, 17 Jul 2020 12:57:42 -0400 Received: from mx0a-001b2d01.pphosted.com ([148.163.156.1]:28842 "EHLO mx0a-001b2d01.pphosted.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1727101AbgGQQ5m (ORCPT ); Fri, 17 Jul 2020 12:57:42 -0400 Received: from pps.filterd (m0098396.ppops.net [127.0.0.1]) by mx0a-001b2d01.pphosted.com (8.16.0.42/8.16.0.42) with SMTP id 06HGXVGp111927; Fri, 17 Jul 2020 12:57:30 -0400 Received: from ppma04fra.de.ibm.com (6a.4a.5195.ip4.static.sl-reverse.com [149.81.74.106]) by mx0a-001b2d01.pphosted.com with ESMTP id 32axd2mynq-1 (version=TLSv1.2 cipher=ECDHE-RSA-AES256-GCM-SHA384 bits=256 verify=NOT); Fri, 17 Jul 2020 12:57:29 -0400 Received: from pps.filterd (ppma04fra.de.ibm.com [127.0.0.1]) by ppma04fra.de.ibm.com (8.16.0.42/8.16.0.42) with SMTP id 06HGoclJ016655; Fri, 17 Jul 2020 16:57:27 GMT Received: from b06avi18626390.portsmouth.uk.ibm.com (b06avi18626390.portsmouth.uk.ibm.com [9.149.26.192]) by ppma04fra.de.ibm.com with ESMTP id 32b6jsr8tn-1 (version=TLSv1.2 cipher=ECDHE-RSA-AES256-GCM-SHA384 bits=256 verify=NOT); Fri, 17 Jul 2020 16:57:27 +0000 Received: from b06wcsmtp001.portsmouth.uk.ibm.com (b06wcsmtp001.portsmouth.uk.ibm.com [9.149.105.160]) by b06avi18626390.portsmouth.uk.ibm.com (8.14.9/8.14.9/NCO v10.0) with ESMTP id 06HGu1Dt52756758 (version=TLSv1/SSLv3 cipher=DHE-RSA-AES256-GCM-SHA384 bits=256 verify=OK); Fri, 17 Jul 2020 16:56:01 GMT Received: from b06wcsmtp001.portsmouth.uk.ibm.com (unknown [127.0.0.1]) by IMSVA (Postfix) with ESMTP id C99FBA405F; Fri, 17 Jul 2020 16:57:24 +0000 (GMT) Received: from b06wcsmtp001.portsmouth.uk.ibm.com (unknown [127.0.0.1]) by IMSVA (Postfix) with ESMTP id 51817A405B; Fri, 17 Jul 2020 16:57:24 +0000 (GMT) Received: from localhost.localdomain (unknown [9.145.6.1]) by b06wcsmtp001.portsmouth.uk.ibm.com (Postfix) with ESMTP; Fri, 17 Jul 2020 16:57:24 +0000 (GMT) From: Ilya Leoshkevich To: Alexei Starovoitov , Daniel Borkmann Cc: bpf@vger.kernel.org, Heiko Carstens , Vasily Gorbik , Ilya Leoshkevich Subject: [PATCH 5/5] s390/bpf: use bpf_skip() in bpf_jit_prologue() Date: Fri, 17 Jul 2020 18:53:26 +0200 Message-Id: <20200717165326.6786-6-iii@linux.ibm.com> X-Mailer: git-send-email 2.25.4 In-Reply-To: <20200717165326.6786-1-iii@linux.ibm.com> References: <20200717165326.6786-1-iii@linux.ibm.com> MIME-Version: 1.0 X-TM-AS-GCONF: 00 X-Proofpoint-Virus-Version: vendor=fsecure engine=2.50.10434:6.0.235, 18.0.687 definitions=2020-07-17_08:2020-07-17,2020-07-17 signatures=0 X-Proofpoint-Spam-Details: rule=outbound_notspam policy=outbound score=0 lowpriorityscore=0 adultscore=0 clxscore=1015 mlxscore=0 malwarescore=0 impostorscore=0 suspectscore=0 priorityscore=1501 bulkscore=0 phishscore=0 spamscore=0 mlxlogscore=999 classifier=spam adjust=0 reason=mlx scancount=1 engine=8.12.0-2006250000 definitions=main-2007170115 Sender: bpf-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: bpf@vger.kernel.org Now that we have bpf_skip() for emitting nops, use it in bpf_jit_prologue() in order to reduce code duplication. Signed-off-by: Ilya Leoshkevich --- arch/s390/net/bpf_jit_comp.c | 9 +++++---- 1 file changed, 5 insertions(+), 4 deletions(-) diff --git a/arch/s390/net/bpf_jit_comp.c b/arch/s390/net/bpf_jit_comp.c index e68854ab27ae..be4b8532dd3c 100644 --- a/arch/s390/net/bpf_jit_comp.c +++ b/arch/s390/net/bpf_jit_comp.c @@ -520,10 +520,11 @@ static void bpf_jit_prologue(struct bpf_jit *jit, u32 stack_depth) /* xc STK_OFF_TCCNT(4,%r15),STK_OFF_TCCNT(%r15) */ _EMIT6(0xd703f000 | STK_OFF_TCCNT, 0xf000 | STK_OFF_TCCNT); } else { - /* j tail_call_start: NOP if no tail calls are used */ - EMIT4_PCREL(0xa7f40000, 6); - /* bcr 0,%0 */ - EMIT2(0x0700, 0, REG_0); + /* + * There are no tail calls. Insert nops in order to have + * tail_call_start at a predictable offset. + */ + bpf_skip(jit, 6); } /* Tail calls have to skip above initialization */ jit->tail_call_start = jit->prg;