{"id":2219317,"url":"http://patchwork.ozlabs.org/api/1.0/patches/2219317/?format=json","project":{"id":2,"url":"http://patchwork.ozlabs.org/api/1.0/projects/2/?format=json","name":"Linux PPC development","link_name":"linuxppc-dev","list_id":"linuxppc-dev.lists.ozlabs.org","list_email":"linuxppc-dev@lists.ozlabs.org","web_url":"https://github.com/linuxppc/wiki/wiki","scm_url":"https://git.kernel.org/pub/scm/linux/kernel/git/powerpc/linux.git","webscm_url":"https://git.kernel.org/pub/scm/linux/kernel/git/powerpc/linux.git/"},"msgid":"<20260403004011.44417-4-adubey@linux.ibm.com>","date":"2026-04-03T00:40:09","name":"[v2,3/5] selftest/bpf: Fixing powerpc JIT disassembly failure","commit_ref":null,"pull_url":null,"state":"new","archived":false,"hash":"a8e0ec09391b4ab3db9e9f9cacd3e247c3733497","submitter":{"id":88541,"url":"http://patchwork.ozlabs.org/api/1.0/people/88541/?format=json","name":"adubey","email":"adubey@linux.ibm.com"},"delegate":null,"mbox":"http://patchwork.ozlabs.org/project/linuxppc-dev/patch/20260403004011.44417-4-adubey@linux.ibm.com/mbox/","series":[{"id":498551,"url":"http://patchwork.ozlabs.org/api/1.0/series/498551/?format=json","date":"2026-04-03T00:40:06","name":"powerpc/bpf: Add support for verifier selftest","version":2,"mbox":"http://patchwork.ozlabs.org/series/498551/mbox/"}],"check":"pending","checks":"http://patchwork.ozlabs.org/api/patches/2219317/checks/","tags":{},"headers":{"Return-Path":"\n ","X-Original-To":["incoming@patchwork.ozlabs.org","linuxppc-dev@lists.ozlabs.org"],"Delivered-To":"patchwork-incoming@legolas.ozlabs.org","Authentication-Results":["legolas.ozlabs.org;\n\tdkim=pass (2048-bit key;\n unprotected) header.d=ibm.com header.i=@ibm.com header.a=rsa-sha256\n header.s=pp1 header.b=VE3The7E;\n\tdkim-atps=neutral","legolas.ozlabs.org;\n spf=pass (sender SPF authorized) smtp.mailfrom=lists.ozlabs.org\n (client-ip=2404:9400:21b9:f100::1; helo=lists.ozlabs.org;\n envelope-from=linuxppc-dev+bounces-19235-incoming=patchwork.ozlabs.org@lists.ozlabs.org;\n receiver=patchwork.ozlabs.org)","lists.ozlabs.org;\n arc=none smtp.remote-ip=148.163.158.5","lists.ozlabs.org;\n dmarc=pass (p=none dis=none) header.from=linux.ibm.com","lists.ozlabs.org;\n\tdkim=pass (2048-bit key;\n unprotected) header.d=ibm.com header.i=@ibm.com header.a=rsa-sha256\n header.s=pp1 header.b=VE3The7E;\n\tdkim-atps=neutral","lists.ozlabs.org;\n spf=pass (sender SPF authorized) smtp.mailfrom=linux.ibm.com\n (client-ip=148.163.158.5; helo=mx0b-001b2d01.pphosted.com;\n envelope-from=adubey@linux.ibm.com; receiver=lists.ozlabs.org)"],"Received":["from lists.ozlabs.org (lists.ozlabs.org\n [IPv6:2404:9400:21b9:f100::1])\n\t(using TLSv1.3 with cipher TLS_AES_256_GCM_SHA384 (256/256 bits)\n\t key-exchange x25519)\n\t(No client certificate requested)\n\tby legolas.ozlabs.org (Postfix) with ESMTPS id 4fmtzM71gtz1yCt\n\tfor ; Fri, 03 Apr 2026 07:40:47 +1100 (AEDT)","from boromir.ozlabs.org (localhost [127.0.0.1])\n\tby lists.ozlabs.org (Postfix) with ESMTP id 4fmtzL2pHGz2yqF;\n\tFri, 03 Apr 2026 07:40:46 +1100 (AEDT)","from mx0b-001b2d01.pphosted.com (mx0b-001b2d01.pphosted.com\n [148.163.158.5])\n\t(using TLSv1.3 with cipher TLS_AES_256_GCM_SHA384 (256/256 bits)\n\t key-exchange x25519 server-signature RSA-PSS (2048 bits) server-digest\n SHA256)\n\t(No client certificate requested)\n\tby lists.ozlabs.org (Postfix) with ESMTPS id 4fmtzK38Zbz2yhG\n\tfor ; Fri, 03 Apr 2026 07:40:45 +1100 (AEDT)","from pps.filterd (m0353725.ppops.net [127.0.0.1])\n\tby mx0a-001b2d01.pphosted.com (8.18.1.11/8.18.1.11) with ESMTP id\n 632ARD133226794;\n\tThu, 2 Apr 2026 20:40:30 GMT","from ppma21.wdc07v.mail.ibm.com\n (5b.69.3da9.ip4.static.sl-reverse.com [169.61.105.91])\n\tby mx0a-001b2d01.pphosted.com (PPS) with ESMTPS id 4d65dcnmg8-1\n\t(version=TLSv1.2 cipher=ECDHE-RSA-AES256-GCM-SHA384 bits=256 verify=NOT);\n\tThu, 02 Apr 2026 20:40:30 +0000 (GMT)","from pps.filterd (ppma21.wdc07v.mail.ibm.com [127.0.0.1])\n\tby ppma21.wdc07v.mail.ibm.com (8.18.1.2/8.18.1.2) with ESMTP id\n 632HABtr022217;\n\tThu, 2 Apr 2026 20:40:30 GMT","from smtprelay05.fra02v.mail.ibm.com ([9.218.2.225])\n\tby ppma21.wdc07v.mail.ibm.com (PPS) with ESMTPS id 4d6tanbmbv-1\n\t(version=TLSv1.2 cipher=ECDHE-RSA-AES256-GCM-SHA384 bits=256 verify=NOT);\n\tThu, 02 Apr 2026 20:40:29 +0000","from smtpav03.fra02v.mail.ibm.com (smtpav03.fra02v.mail.ibm.com\n [10.20.54.102])\n\tby smtprelay05.fra02v.mail.ibm.com (8.14.9/8.14.9/NCO v10.0) with ESMTP id\n 632KeQMX46531006\n\t(version=TLSv1/SSLv3 cipher=DHE-RSA-AES256-GCM-SHA384 bits=256 verify=OK);\n\tThu, 2 Apr 2026 20:40:26 GMT","from smtpav03.fra02v.mail.ibm.com (unknown [127.0.0.1])\n\tby IMSVA (Postfix) with ESMTP id 0CC982004B;\n\tThu, 2 Apr 2026 20:40:26 +0000 (GMT)","from smtpav03.fra02v.mail.ibm.com (unknown [127.0.0.1])\n\tby IMSVA (Postfix) with ESMTP id 0777820040;\n\tThu, 2 Apr 2026 20:40:24 +0000 (GMT)","from ltcrain4-lp15.ltc.tadn.ibm.com (unknown [9.5.7.39])\n\tby smtpav03.fra02v.mail.ibm.com (Postfix) with ESMTP;\n\tThu, 2 Apr 2026 20:40:23 +0000 (GMT)"],"ARC-Seal":"i=1; a=rsa-sha256; d=lists.ozlabs.org; s=201707; t=1775162446;\n\tcv=none;\n b=cjkhPSNny0pouABD2U4NuoLbi2NCbDrIDfT/whHfJIyhcwXxD0g5LM9Hu4bRV3UgHZHm2sov2mhyJ6palHjW9o8lhDdqldkiwGXCO7ahGv5zHO4WP+x2C6sjDFCaDMy4R1iSpw+34fj1fnohJtkUttBl6tUJZCkjkfBY3S0wRKtysYo+hwGW0QJyZ2rPemXycqKuIUXFQ7oW7//eLIvbW3E1MXaJfxdKsgTsyjIobL6hE2zdQzkeA9H9OGJegUVSdllOCBb2OkGjelEAe2bzmA/ZH3XdNd8lyt5pyf6dBVyLk9jxodr9m0YFkQQTohxkgHsCoSQNZi84+PlusKFZAg==","ARC-Message-Signature":"i=1; a=rsa-sha256; d=lists.ozlabs.org; s=201707;\n\tt=1775162446; c=relaxed/relaxed;\n\tbh=0yx8o1vLrB65vCCuGPvOK4QUoLEyCAyYVHQNpTUGhjI=;\n\th=From:To:Cc:Subject:Date:Message-ID:In-Reply-To:References:\n\t MIME-Version;\n b=VvwTHqBrD0de5SX0KKFax7PuoliDoKkZSPrGFn5UWqRRbS0MLkBLoFmUBZyebdnl5s8pnXMu9/+aKYJTIn89mmO9LM30j6oFCY8CVIiwAl8OCfGEcfpNhjhvFSubAYQ6zMo3G1Hk6daKif2hNOvPokqY3qzf7SKhGauCxgdTTsOF0HnGTc80AQ51y4r19n4wS2FaIY40BeNkcUaeJppPoViAMvSlIMnnA/mkyy9yFWUcS27h/Xxnp6RYNvEpvhuE3tqa2VyXUedkLSJUavO6a8ey061s133pX/D/G2F1aU1h06dwx+Djo4ibg7GIE3HbE09y3n9qrcuK9K78mCglBw==","ARC-Authentication-Results":"i=1; lists.ozlabs.org;\n dmarc=pass (p=none dis=none) header.from=linux.ibm.com;\n dkim=pass (2048-bit key;\n unprotected) header.d=ibm.com header.i=@ibm.com header.a=rsa-sha256\n header.s=pp1 header.b=VE3The7E; dkim-atps=neutral;\n spf=pass (client-ip=148.163.158.5; helo=mx0b-001b2d01.pphosted.com;\n envelope-from=adubey@linux.ibm.com;\n receiver=lists.ozlabs.org) smtp.mailfrom=linux.ibm.com","DKIM-Signature":"v=1; a=rsa-sha256; c=relaxed/relaxed; d=ibm.com; h=cc\n\t:content-transfer-encoding:date:from:in-reply-to:message-id\n\t:mime-version:references:subject:to; s=pp1; bh=0yx8o1vLrB65vCCuG\n\tPvOK4QUoLEyCAyYVHQNpTUGhjI=; b=VE3The7ETh/fSES5LmrBKWFadIYoreMUx\n\tmvW6SVV2nFKkcC0ZmRZV9KJHL/VxXNJbHBuUXhU4v8iTC05386YQah4QRhebngr4\n\tWxAK9C3n+EbTD6PTWmNQQINeohupVUoXzN+8o0jvBUoXgWW79qdAyRABt7rLlMZD\n\tPWh1paxkP8vf89CLlav9Bi9damjP0AB5mEHBx/GVSyXvtFLcAnttKbFAIXP6mlek\n\taYVb3syCs4Eeuf5HzNvzujjwfmW38IlS3spo6k0UvXGDXAReGJSCdxgLWDKz+KdF\n\tt4ensHa62GmYFe/jwlHfOGvuxata7GpIEDo+l7Iyok1ux9f/diSuA==","From":"adubey@linux.ibm.com","To":"linuxppc-dev@lists.ozlabs.org","Cc":"hbathini@linux.ibm.com, bpf@vger.kernel.org, maddy@linux.ibm.com,\n ast@kernel.org, andrii@kernel.org, daniel@iogearbox.net,\n shuah@kernel.org, linux-kselftest@vger.kernel.org,\n stable@vger.kernel.org, Abhishek Dubey ","Subject":"[PATCH v2 3/5] selftest/bpf: Fixing powerpc JIT disassembly failure","Date":"Thu, 2 Apr 2026 20:40:09 -0400","Message-ID":"<20260403004011.44417-4-adubey@linux.ibm.com>","X-Mailer":"git-send-email 2.52.0","In-Reply-To":"<20260403004011.44417-1-adubey@linux.ibm.com>","References":"<20260403004011.44417-1-adubey@linux.ibm.com>","X-Mailing-List":"linuxppc-dev@lists.ozlabs.org","List-Id":"","List-Help":"","List-Owner":"","List-Post":"","List-Archive":",\n ","List-Subscribe":",\n ,\n ","List-Unsubscribe":"","Precedence":"list","MIME-Version":"1.0","Content-Transfer-Encoding":"8bit","X-TM-AS-GCONF":"00","X-Authority-Analysis":"v=2.4 cv=RsjI7SmK c=1 sm=1 tr=0 ts=69ced43e cx=c_pps\n a=GFwsV6G8L6GxiO2Y/PsHdQ==:117 a=GFwsV6G8L6GxiO2Y/PsHdQ==:17\n a=A5OVakUREuEA:10 a=VkNPw1HP01LnGYTKEx00:22 a=RnoormkPH1_aCDwRdu11:22\n a=V8glGbnc2Ofi9Qvn3v5h:22 a=VnNF1IyMAAAA:8 a=kVjrMc9Is9WrAmO39HcA:9","X-Proofpoint-GUID":"Br0a184axX6Mksfpt2sT_lg-_KkNxH8w","X-Proofpoint-Spam-Details-Enc":"AW1haW4tMjYwNDAyMDE4MSBTYWx0ZWRfX5G2bVXTxaIot\n StYMSgL2l/u0gWZwj/b1kjMADuXL9GWDodpnuDsTJZgQk9CN/jN7Tm0B4bYhvDAtnTbqEPx8vTg\n E5pmHLsJLkREVKqXMaxqeokOGqdwUA2CLvKAWd/KDrL2fBiXzMfk4Nc9iqV/jyhQZUkeHwxaa1X\n VTeqL1tU/nZzxOQ3ifwA/S8LEY4T/TIN1cyfZn3WS3Ga9i7NEuvrpJHebcT6pe9l9wc6OQSGMUv\n YkJ9HQNaGBqQpuHB/Ln4tcPI2WLmoPNM5EZrcxxJX0qAyNQKVwAK8O8u8JCqPKMhPaL7EKmRw8U\n A0kaQG9E14Zk00guguqLDFxc27MbZ25lt/DVhKeZ80mOf2ifA8z6L585gXdcPPGQVmYnJjF7fPO\n 2a2rD1LrYVN/L/BvupW0x55Eg62sEJIbpzrGUB5dw15OdXhPCvfL/ff+3wkmpj3abgYsPR8Volb\n v736/xeq85DP4ao9N3w==","X-Proofpoint-ORIG-GUID":"Br0a184axX6Mksfpt2sT_lg-_KkNxH8w","X-Proofpoint-Virus-Version":"vendor=baseguard\n engine=ICAP:2.0.293,Aquarius:18.0.1143,Hydra:6.1.51,FMLib:17.12.100.49\n definitions=2026-04-02_03,2026-04-02_05,2025-10-01_01","X-Proofpoint-Spam-Details":"rule=outbound_notspam policy=outbound score=0\n impostorscore=0 bulkscore=0 priorityscore=1501 lowpriorityscore=0\n suspectscore=0 malwarescore=0 spamscore=0 clxscore=1015 phishscore=0\n adultscore=0 classifier=typeunknown authscore=0 authtc= authcc=\n route=outbound adjust=0 reason=mlx scancount=1 engine=8.22.0-2603050001\n definitions=main-2604020181","X-Spam-Status":"No, score=1.7 required=3.0 tests=DATE_IN_FUTURE_03_06,\n\tDKIM_SIGNED,DKIM_VALID,RCVD_IN_DNSWL_LOW,RCVD_IN_MSPIKE_H4,\n\tRCVD_IN_MSPIKE_WL,SPF_HELO_NONE,SPF_PASS autolearn=disabled\n\tversion=4.0.1 OzLabs 8","X-Spam-Level":"*","X-Spam-Checker-Version":"SpamAssassin 4.0.1 (2024-03-25) on lists.ozlabs.org"},"content":"From: Abhishek Dubey \n\nEnsure that the trampoline stubs JITed at the tail of the\nepilogue do not expose the dummy trampoline address stored\nin the last 8 bytes (for both 64-bit and 32-bit PowerPC)\nto the disassembly flow. Prevent the disassembler from\ningesting this memory address, as it may occasionally decode\ninto a seemingly valid but incorrect instruction. Fix this\nissue by truncating the last 8 bytes from JITed buffers\nbefore supplying them for disassembly.\n\nSigned-off-by: Abhishek Dubey \n---\n tools/testing/selftests/bpf/jit_disasm_helpers.c | 13 ++++++++++++-\n 1 file changed, 12 insertions(+), 1 deletion(-)","diff":"diff --git a/tools/testing/selftests/bpf/jit_disasm_helpers.c b/tools/testing/selftests/bpf/jit_disasm_helpers.c\nindex 364c557c5115..4c6bcbe08491 100644\n--- a/tools/testing/selftests/bpf/jit_disasm_helpers.c\n+++ b/tools/testing/selftests/bpf/jit_disasm_helpers.c\n@@ -170,9 +170,11 @@ int get_jited_program_text(int fd, char *text, size_t text_sz)\n \tstruct bpf_prog_info info = {};\n \t__u32 info_len = sizeof(info);\n \t__u32 jited_funcs, len, pc;\n+\t__u32 trunc_len = 0;\n \t__u32 *func_lens = NULL;\n \tFILE *text_out = NULL;\n \tuint8_t *image = NULL;\n+\tchar *triple = NULL;\n \tint i, err = 0;\n \n \tif (!llvm_initialized) {\n@@ -216,9 +218,18 @@ int get_jited_program_text(int fd, char *text, size_t text_sz)\n \tif (!ASSERT_OK(err, \"bpf_prog_get_info_by_fd #2\"))\n \t\tgoto out;\n \n+\t/*\n+\t * last 8 bytes contains dummy_trampoline address in JIT\n+\t * output for 64-bit and 32-bit powerpc, which can't\n+\t * disassemble a to valid instruction.\n+\t */\n+\ttriple = LLVMGetDefaultTargetTriple();\n+\tif (strstr(triple, \"powerpc\"))\n+\t\ttrunc_len = 8;\n+\n \tfor (pc = 0, i = 0; i < jited_funcs; ++i) {\n \t\tfprintf(text_out, \"func #%d:\\n\", i);\n-\t\tdisasm_one_func(text_out, image + pc, func_lens[i]);\n+\t\tdisasm_one_func(text_out, image + pc, func_lens[i] - trunc_len);\n \t\tfprintf(text_out, \"\\n\");\n \t\tpc += func_lens[i];\n \t}\n","prefixes":["v2","3/5"]}