From nobody Fri Dec 19 07:24:12 2025 Received: from mailgw.kylinos.cn (mailgw.kylinos.cn [124.126.103.232]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by smtp.subspace.kernel.org (Postfix) with ESMTPS id 798ED2EB872; Wed, 17 Dec 2025 06:15:00 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.client-ip=124.126.103.232 ARC-Seal: i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1765952103; cv=none; b=ovlSWCZtCZ5uspIlxzpVYveygMKEHstN6RACrE6RIabmv2Tz3AkvIDkYuU5++tMZyyATXODeyJY03+jc8L0ONvVnxZRQvczFe+F0rlmJHOUbw5h6SE23jp9Jd75rwXOWkP9dm0z68MVwF0McwggXONRAVn13PFY8BL+s3VUoNIM= ARC-Message-Signature: i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1765952103; c=relaxed/simple; bh=WLDcyUQpfa0qKW1T1Zd8X2+eNMhk9ImYjFtpapGBMWU=; h=From:To:Cc:Subject:Date:Message-Id:In-Reply-To:References: MIME-Version; b=trHSZX/4pbIt6mC0JaA605iOVveY5avEWYg4Fp69RDglcPP81MsENo6vcnVL9F42O07Qvqy/R0DBVcpIANb5/20kapiEf5vnWeK9JK4Pl6ymCGoZYxeLCaqcOWdYUOG3Lb7GSbHXw4KdC85FBU4Nc0gpEWNB82930m8LbA2MWEE= ARC-Authentication-Results: i=1; smtp.subspace.kernel.org; dmarc=none (p=none dis=none) header.from=kylinos.cn; spf=pass smtp.mailfrom=kylinos.cn; arc=none smtp.client-ip=124.126.103.232 Authentication-Results: smtp.subspace.kernel.org; dmarc=none (p=none dis=none) header.from=kylinos.cn Authentication-Results: smtp.subspace.kernel.org; spf=pass smtp.mailfrom=kylinos.cn X-UUID: b45ccc7cdb0f11f0a38c85956e01ac42-20251217 X-CTIC-Tags: HR_CC_COUNT, HR_CC_DOMAIN_COUNT, HR_CC_NO_NAME, HR_CTE_8B, HR_CTT_MISS HR_DATE_H, HR_DATE_WKD, HR_DATE_ZONE, HR_FROM_NAME, HR_SJ_DIGIT_LEN HR_SJ_LANG, HR_SJ_LEN, HR_SJ_LETTER, HR_SJ_NOR_SYM, HR_SJ_PHRASE HR_SJ_PHRASE_LEN, HR_SJ_WS, HR_TO_COUNT, HR_TO_DOMAIN_COUNT, HR_TO_NO_NAME IP_UNTRUSTED, SRC_UNTRUSTED, IP_UNFAMILIAR, SRC_UNFAMILIAR, DN_TRUSTED SRC_TRUSTED, SA_EXISTED, SN_EXISTED, SPF_NOPASS, DKIM_NOPASS DMARC_NOPASS, CIE_BAD, CIE_GOOD_SPF, CIE_UNKNOWN, GTI_FG_BS GTI_RG_INFO, GTI_C_BU, AMN_GOOD, ABX_MISS_RDNS X-CID-P-RULE: Release_Ham X-CID-O-INFO: VERSION:1.3.6,REQID:66f060b5-49c3-4c94-be10-6e82ec42ed6f,IP:10,U RL:0,TC:0,Content:0,EDM:0,RT:0,SF:-5,FILE:0,BULK:0,RULE:Release_Ham,ACTION :release,TS:5 X-CID-INFO: VERSION:1.3.6,REQID:66f060b5-49c3-4c94-be10-6e82ec42ed6f,IP:10,URL :0,TC:0,Content:0,EDM:0,RT:0,SF:-5,FILE:0,BULK:0,RULE:Release_Ham,ACTION:r elease,TS:5 X-CID-META: VersionHash:a9d874c,CLOUDID:9ed4d91d2c7b25ac4dd7b7b3ed3762e8,BulkI D:251217141457MPWBEX6H,BulkQuantity:0,Recheck:0,SF:17|19|38|66|78|81|82|10 2|127|850|898,TC:nil,Content:0|15|50,EDM:-3,IP:-2,URL:0,File:nil,RT:nil,Bu lk:nil,QS:nil,BEC:nil,COL:0,OSI:0,OSA:0,AV:0,LES:1,SPR:NO,DKR:0,DKP:0,BRR: 0,BRE:0,ARC:0 X-CID-BVR: 2,SSN|SDN X-CID-BAS: 2,SSN|SDN,0,_ X-CID-FACTOR: TF_CID_SPAM_SNR,TF_CID_SPAM_FAS,TF_CID_SPAM_FSD X-CID-RHF: D41D8CD98F00B204E9800998ECF8427E X-UUID: b45ccc7cdb0f11f0a38c85956e01ac42-20251217 X-User: duanchenghao@kylinos.cn Received: from localhost.localdomain [(183.242.174.20)] by mailgw.kylinos.cn (envelope-from ) (Generic MTA) with ESMTP id 612073974; Wed, 17 Dec 2025 14:14:54 +0800 From: Chenghao Duan To: yangtiezhu@loongson.cn, rostedt@goodmis.org, mhiramat@kernel.org, mark.rutland@arm.com, hengqi.chen@gmail.com, chenhuacai@kernel.org Cc: kernel@xen0n.name, zhangtianyang@loongson.cn, masahiroy@kernel.org, linux-kernel@vger.kernel.org, loongarch@lists.linux.dev, bpf@vger.kernel.org, duanchenghao@kylinos.cn, youling.tang@linux.dev, jianghaoran@kylinos.cn, vincent.mc.li@gmail.com, linux-trace-kernel@vger.kernel.org Subject: [PATCH v4 6/7] LoongArch: BPF: Enhance the bpf_arch_text_poke() function Date: Wed, 17 Dec 2025 14:14:34 +0800 Message-Id: <20251217061435.802204-7-duanchenghao@kylinos.cn> X-Mailer: git-send-email 2.25.1 In-Reply-To: <20251217061435.802204-1-duanchenghao@kylinos.cn> References: <20251217061435.802204-1-duanchenghao@kylinos.cn> Precedence: bulk X-Mailing-List: linux-kernel@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 Content-Transfer-Encoding: quoted-printable Content-Type: text/plain; charset="utf-8" Enhance the bpf_arch_text_poke() function to enable accurate location of BPF program entry points. When modifying the entry point of a BPF program, skip the move t0, ra instruction to ensure the correct logic and copy of the jump address. Signed-off-by: Chenghao Duan --- arch/loongarch/net/bpf_jit.c | 15 ++++++++++++++- 1 file changed, 14 insertions(+), 1 deletion(-) diff --git a/arch/loongarch/net/bpf_jit.c b/arch/loongarch/net/bpf_jit.c index 3dbabacc8856..0c16a1b18e8f 100644 --- a/arch/loongarch/net/bpf_jit.c +++ b/arch/loongarch/net/bpf_jit.c @@ -1290,6 +1290,10 @@ int bpf_arch_text_poke(void *ip, enum bpf_text_poke_= type old_t, void *new_addr) { int ret; + unsigned long size =3D 0; + unsigned long offset =3D 0; + char namebuf[KSYM_NAME_LEN]; + void *image =3D NULL; bool is_call; u32 old_insns[LOONGARCH_LONG_JUMP_NINSNS] =3D {[0 ... 4] =3D INSN_NOP}; u32 new_insns[LOONGARCH_LONG_JUMP_NINSNS] =3D {[0 ... 4] =3D INSN_NOP}; @@ -1297,9 +1301,18 @@ int bpf_arch_text_poke(void *ip, enum bpf_text_poke_= type old_t, /* Only poking bpf text is supported. Since kernel function entry * is set up by ftrace, we rely on ftrace to poke kernel functions. */ - if (!is_bpf_text_address((unsigned long)ip)) + if (!__bpf_address_lookup((unsigned long)ip, &size, &offset, namebuf)) return -ENOTSUPP; =20 + image =3D ip - offset; + /* zero offset means we're poking bpf prog entry */ + if (offset =3D=3D 0) + /* skip to the nop instruction in bpf prog entry: + * move t0, ra + * nop + */ + ip =3D image + LOONGARCH_INSN_SIZE; + is_call =3D old_t =3D=3D BPF_MOD_CALL; ret =3D emit_jump_or_nops(old_addr, ip, old_insns, is_call); if (ret) --=20 2.25.1