From nobody Tue Dec 2 02:29:52 2025 Received: from mx0a-001b2d01.pphosted.com (mx0a-001b2d01.pphosted.com [148.163.156.1]) (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 22A5335FF73; Wed, 19 Nov 2025 13:24:56 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.client-ip=148.163.156.1 ARC-Seal: i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1763558699; cv=none; b=d8CDaiGHaLvSUjZglUKEQkgEjCVu3D8milSeMo/mCiq997F1Mlrj0LoEw9bDO8lOEskvHVMkr3qiZpUpLWMt4YXIhury5HjGwD3bKECX0r0pkPYTf2Aqcx0X+B7avMqbX6uqpsoxxGvzUTaXzUNUeysPeMajrVgdVcnCt4W5D8E= ARC-Message-Signature: i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1763558699; c=relaxed/simple; bh=nBrq+RdgNfMc1ur3lIbsaNPcuu3pASuyi/IdKr8/EoI=; h=From:To:Cc:Subject:Date:Message-ID:In-Reply-To:References: MIME-Version; b=GEb3f58eUoeazMK9ZkNJf6fDhipJZaRsivX9lIU9kzaDtoAtIIzGItDW5laSDnh11FZqmBzargfQLKN0PzdOU6z97GNcsfG621taOMBd5NHrFFS/DKoZ/zxJTA+kZxd3B4CBwE1k+LNnG6pYpiBCdrgp58Hj2Vx/lxxrdjWzrvk= ARC-Authentication-Results: i=1; smtp.subspace.kernel.org; dmarc=pass (p=none dis=none) header.from=linux.ibm.com; spf=pass smtp.mailfrom=linux.ibm.com; dkim=pass (2048-bit key) header.d=ibm.com header.i=@ibm.com header.b=fUOeqjf/; arc=none smtp.client-ip=148.163.156.1 Authentication-Results: smtp.subspace.kernel.org; dmarc=pass (p=none dis=none) header.from=linux.ibm.com Authentication-Results: smtp.subspace.kernel.org; spf=pass smtp.mailfrom=linux.ibm.com Authentication-Results: smtp.subspace.kernel.org; dkim=pass (2048-bit key) header.d=ibm.com header.i=@ibm.com header.b="fUOeqjf/" Received: from pps.filterd (m0356517.ppops.net [127.0.0.1]) by mx0a-001b2d01.pphosted.com (8.18.1.2/8.18.1.2) with ESMTP id 5AJ6Zdrm020334; Wed, 19 Nov 2025 13:23:36 GMT DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=ibm.com; h=cc :content-transfer-encoding:date:from:in-reply-to:message-id :mime-version:references:subject:to; s=pp1; bh=ICCfn5d8Ymkg1VuzL DcLXzjBqW3Luy6UcZfak1nf4ac=; b=fUOeqjf/5PIVsyQaf/WVJ2WrbNv/gq/qK h24dWMohX0E7qR+r91QrZ0fRmF4ye2PAF18aUs17DP/KZGiTVeJESLhfzX5eiaD6 NhBzo1vKCLLHj24y5qsRTgvVIl0Gnw6Lncg/JT62zm1HDn/b+cETIfAuDA+kxxqY tjdys9cDqhbRO8uLkJslG2VHT/dGqeJvfbVBb+2G+V3PVx2rTZ7Y+VBo3GCxW7qG pn0U1sASaOdjMMaZm1suO9R9KBwKIHOx+xGX2nwlV6337YY+0aZ5agYS4l387qeq jwoFRMlOfGAMq/gX6F6+guBRK9sOgYwJqVCeyGk7QCncEJ48attRw== Received: from pps.reinject (localhost [127.0.0.1]) by mx0a-001b2d01.pphosted.com (PPS) with ESMTPS id 4aejjw8mxv-1 (version=TLSv1.2 cipher=ECDHE-RSA-AES256-GCM-SHA384 bits=256 verify=NOT); Wed, 19 Nov 2025 13:23:36 +0000 (GMT) Received: from m0356517.ppops.net (m0356517.ppops.net [127.0.0.1]) by pps.reinject (8.18.1.12/8.18.0.8) with ESMTP id 5AJDHjrV014737; Wed, 19 Nov 2025 13:23:35 GMT Received: from ppma13.dal12v.mail.ibm.com (dd.9e.1632.ip4.static.sl-reverse.com [50.22.158.221]) by mx0a-001b2d01.pphosted.com (PPS) with ESMTPS id 4aejjw8mxp-1 (version=TLSv1.2 cipher=ECDHE-RSA-AES256-GCM-SHA384 bits=256 verify=NOT); Wed, 19 Nov 2025 13:23:35 +0000 (GMT) Received: from pps.filterd (ppma13.dal12v.mail.ibm.com [127.0.0.1]) by ppma13.dal12v.mail.ibm.com (8.18.1.2/8.18.1.2) with ESMTP id 5AJCYSr3007031; Wed, 19 Nov 2025 13:23:34 GMT Received: from smtprelay07.fra02v.mail.ibm.com ([9.218.2.229]) by ppma13.dal12v.mail.ibm.com (PPS) with ESMTPS id 4af62jgkcd-1 (version=TLSv1.2 cipher=ECDHE-RSA-AES256-GCM-SHA384 bits=256 verify=NOT); Wed, 19 Nov 2025 13:23:34 +0000 Received: from smtpav02.fra02v.mail.ibm.com (smtpav02.fra02v.mail.ibm.com [10.20.54.101]) by smtprelay07.fra02v.mail.ibm.com (8.14.9/8.14.9/NCO v10.0) with ESMTP id 5AJDNUeW44171684 (version=TLSv1/SSLv3 cipher=DHE-RSA-AES256-GCM-SHA384 bits=256 verify=OK); Wed, 19 Nov 2025 13:23:30 GMT Received: from smtpav02.fra02v.mail.ibm.com (unknown [127.0.0.1]) by IMSVA (Postfix) with ESMTP id A8D9420040; Wed, 19 Nov 2025 13:23:30 +0000 (GMT) Received: from smtpav02.fra02v.mail.ibm.com (unknown [127.0.0.1]) by IMSVA (Postfix) with ESMTP id 2B6C820043; Wed, 19 Nov 2025 13:23:30 +0000 (GMT) Received: from tuxmaker.boeblingen.de.ibm.com (unknown [9.152.85.9]) by smtpav02.fra02v.mail.ibm.com (Postfix) with ESMTP; Wed, 19 Nov 2025 13:23:30 +0000 (GMT) From: Jens Remus To: linux-kernel@vger.kernel.org, linux-trace-kernel@vger.kernel.org, bpf@vger.kernel.org, x86@kernel.org, linux-mm@kvack.org, Steven Rostedt Cc: Jens Remus , Josh Poimboeuf , Masami Hiramatsu , Mathieu Desnoyers , Peter Zijlstra , Ingo Molnar , Jiri Olsa , Arnaldo Carvalho de Melo , Namhyung Kim , Thomas Gleixner , Andrii Nakryiko , Indu Bhagat , "Jose E. Marchesi" , Beau Belgrave , Linus Torvalds , Andrew Morton , Florian Weimer , Kees Cook , "Carlos O'Donell" , Sam James , Dylan Hatch , Borislav Petkov , Dave Hansen , David Hildenbrand , "H. Peter Anvin" , "Liam R. Howlett" , Lorenzo Stoakes , Michal Hocko , Mike Rapoport , Suren Baghdasaryan , Vlastimil Babka , Heiko Carstens , Vasily Gorbik Subject: [PATCH v12 08/13] unwind_user/sframe: Add support for outermost frame indication Date: Wed, 19 Nov 2025 14:23:18 +0100 Message-ID: <20251119132323.1281768-9-jremus@linux.ibm.com> X-Mailer: git-send-email 2.48.1 In-Reply-To: <20251119132323.1281768-1-jremus@linux.ibm.com> References: <20251119132323.1281768-1-jremus@linux.ibm.com> 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 X-TM-AS-GCONF: 00 X-Authority-Analysis: v=2.4 cv=BanVE7t2 c=1 sm=1 tr=0 ts=691dc4d8 cx=c_pps a=AfN7/Ok6k8XGzOShvHwTGQ==:117 a=AfN7/Ok6k8XGzOShvHwTGQ==:17 a=6UeiqGixMTsA:10 a=VkNPw1HP01LnGYTKEx00:22 a=VwQbUJbxAAAA:8 a=7d_E57ReAAAA:8 a=JfrnYn6hAAAA:8 a=yPCof4ZbAAAA:8 a=mDV3o1hIAAAA:8 a=yMhMjlubAAAA:8 a=VnNF1IyMAAAA:8 a=Z4Rwk6OoAAAA:8 a=20KFwNOVAAAA:8 a=7mOBRU54AAAA:8 a=mFg4y33aAicYmUfzDuoA:9 a=jhqOcbufqs7Y1TYCrUUU:22 a=1CNFftbPRP8L7MoqJWF3:22 a=HkZW87K1Qel5hWWM3VKY:22 a=wa9RWnbW_A1YIeRBVszw:22 X-Proofpoint-Spam-Details-Enc: AW1haW4tMjUxMTE1MDAzMiBTYWx0ZWRfX0sYAbp2epTJF KwK0o6nV/t/DascHTDAw7LjrSVRelVjU3PChgqNTnUIqNBrR65oSm2XirXhGaq6SmWYXiF9l1o1 BsQhZw9XMFA3APgLGsAzpWdBL5le73BMdkqHwRiBZKgzAka4TyoQ/V6rFSBgo/dSBXgg9LHtznx NdSbabmEonNwBeP4+PV83lwjZMVwR3jfTZTot0Q0bfvhGMA/Z5R0bX++6shrDi2fEkjT1foBBry b+KgQFanPYjh8tQz0YZsoGAsl3XtdIOuJVvRNk5bDVDcwgny0eibC0knYxhDsdUTo5WHxOJwFNT /PwBeGNB/s/bKHBUxF9TtHWloEtkba+Ln2E9Lu+Peanpoy1GCtSZ3uKnat4AHyISNzxApfJNd6v w4n5s2CWsuTbBxxsa84qbBd6dq6cDQ== X-Proofpoint-GUID: Lc5hNVLHNPbVtLhcgANqHWlJnau4aR0p X-Proofpoint-ORIG-GUID: w_ZwY8KvewR66gHHIbtRNLPrA3VLgrnG X-Proofpoint-Virus-Version: vendor=baseguard engine=ICAP:2.0.293,Aquarius:18.0.1121,Hydra:6.1.9,FMLib:17.12.100.49 definitions=2025-11-19_04,2025-11-18_02,2025-10-01_01 X-Proofpoint-Spam-Details: rule=outbound_notspam policy=outbound score=0 malwarescore=0 lowpriorityscore=0 suspectscore=0 spamscore=0 impostorscore=0 priorityscore=1501 clxscore=1015 phishscore=0 bulkscore=0 adultscore=0 classifier=typeunknown authscore=0 authtc= authcc= route=outbound adjust=0 reason=mlx scancount=1 engine=8.19.0-2510240000 definitions=main-2511150032 Content-Type: text/plain; charset="utf-8" SFrame may represent an undefined return address (RA) as SFrame FRE without any offsets as indication for an outermost frame. Cc: Steven Rostedt Cc: Josh Poimboeuf Cc: Masami Hiramatsu Cc: Mathieu Desnoyers Cc: Peter Zijlstra Cc: Ingo Molnar Cc: Jiri Olsa Cc: Arnaldo Carvalho de Melo Cc: Namhyung Kim Cc: Thomas Gleixner Cc: Andrii Nakryiko Cc: Indu Bhagat Cc: "Jose E. Marchesi" Cc: Beau Belgrave Cc: Jens Remus Cc: Linus Torvalds Cc: Andrew Morton Cc: Florian Weimer Cc: Sam James Cc: Kees Cook Cc: "Carlos O'Donell" Signed-off-by: Jens Remus --- Notes (jremus): Changes in v11: - New patch. kernel/unwind/sframe.c | 15 ++++++++++++++- 1 file changed, 14 insertions(+), 1 deletion(-) diff --git a/kernel/unwind/sframe.c b/kernel/unwind/sframe.c index d4ef825b1cbc..1e877c3e5417 100644 --- a/kernel/unwind/sframe.c +++ b/kernel/unwind/sframe.c @@ -33,6 +33,7 @@ struct sframe_fre_internal { s32 ra_off; s32 fp_off; u8 info; + bool ra_undefined; }; =20 DEFINE_STATIC_SRCU(sframe_srcu); @@ -187,6 +188,7 @@ static __always_inline int __read_fre(struct sframe_sec= tion *sec, unsigned char offset_count, offset_size; s32 cfa_off, ra_off, fp_off; unsigned long cur =3D fre_addr; + bool ra_undefined =3D false; unsigned char addr_size; u32 ip_off; u8 info; @@ -205,7 +207,7 @@ static __always_inline int __read_fre(struct sframe_sec= tion *sec, UNSAFE_GET_USER_INC(info, cur, 1, Efault); offset_count =3D SFRAME_FRE_OFFSET_COUNT(info); offset_size =3D offset_size_enum_to_size(SFRAME_FRE_OFFSET_SIZE(info)); - if (!offset_count || !offset_size) + if (!offset_size) return -EFAULT; =20 if (cur + (offset_count * offset_size) > sec->fres_end) @@ -213,6 +215,14 @@ static __always_inline int __read_fre(struct sframe_se= ction *sec, =20 fre->size =3D addr_size + 1 + (offset_count * offset_size); =20 + if (!offset_count) { + cfa_off =3D 0; + ra_off =3D 0; + fp_off =3D 0; + ra_undefined =3D true; + goto done; + } + UNSAFE_GET_USER_INC(cfa_off, cur, offset_size, Efault); offset_count--; =20 @@ -233,11 +243,13 @@ static __always_inline int __read_fre(struct sframe_s= ection *sec, if (offset_count) return -EFAULT; =20 +done: fre->ip_off =3D ip_off; fre->cfa_off =3D cfa_off; fre->ra_off =3D ra_off; fre->fp_off =3D fp_off; fre->info =3D info; + fre->ra_undefined =3D ra_undefined; =20 return 0; =20 @@ -298,6 +310,7 @@ static __always_inline int __find_fre(struct sframe_sec= tion *sec, frame->ra_off =3D fre->ra_off; frame->fp_off =3D fre->fp_off; frame->use_fp =3D SFRAME_FRE_CFA_BASE_REG_ID(fre->info) =3D=3D SFRAME_BA= SE_REG_FP; + frame->outermost =3D fre->ra_undefined; =20 return 0; } --=20 2.48.1