From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from mx0b-001b2d01.pphosted.com (mx0b-001b2d01.pphosted.com [148.163.158.5]) (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 AB3F92FD695; Wed, 22 Oct 2025 14:44:35 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.client-ip=148.163.158.5 ARC-Seal:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1761144277; cv=none; b=VZLFYqonehrVPOk4YgHSldmPFyIeAFvlWhyod7FkHBzLinr+yPZq9W4gNmbbFxeZ3IQGvMAto+OQtJMntkCoSm8CHse4m75Dhm5/26csf96weZgzukFO+A3TiVXcDCsRLeT0lOGQ23EMYOQluna8pvU7oMHJe5SDRQCpjoN9qtY= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1761144277; c=relaxed/simple; bh=POqEM7Hr9uWkmpW8CadFi0AjfwvWWAwgZEbPcVfygjw=; h=From:To:Cc:Subject:Date:Message-ID:In-Reply-To:References: MIME-Version; b=p8hUHljBGic0xjFHC/arCpoz4ExTNhf4euySfYmLrjNgJSjpCBk+MLULwz7F64u/FErjJHrhe0L3S2H+o/0kPZ6JTFw9fM3kiOXnuhGK0IW5yfhg5PDu5n+1sovFSZ6wuCWtLIynCJNdJ2pRTxjm2pj+gy67PWxSWssV6aVHqDA= 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=M+pYsQ2/; arc=none smtp.client-ip=148.163.158.5 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="M+pYsQ2/" Received: from pps.filterd (m0360072.ppops.net [127.0.0.1]) by mx0a-001b2d01.pphosted.com (8.18.1.2/8.18.1.2) with ESMTP id 59M7WQ4M013165; Wed, 22 Oct 2025 14:43:39 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=pYdVG1t1tt/Dxbg/e 8fHwqU+ZHySAtpeMBUdGiGU6Q4=; b=M+pYsQ2/YhROcfdUSaoIm2lW6ZA+EG4jg teXknGaoArJVhxWkQKWqOeZPAaiWocQ36Zt980rRL8iTxW5edw1OvZUQfAjt+ubz Wq4fQNzVkW9/AgjRFkp+FgI6WHINDVLpcQPQuZoEQdLS38UYysGNZJxmrgC4dLvP 1iehLRbwbjLCqY/fzL0nD1RgLqiuPTbvGZmCEhDDgycidH2IZ7264YtczayaIwwD ST8vlS3FluLL5moqWptI757SxgQ7FABozdrJ1umE5gShQxYRNECspzsi1wXIPuFm YH/oRRAyerls/jqNj09/Xl9pKUmpbUm+zn/WoviuFyoyLB9xzQ/uQ== Received: from pps.reinject (localhost [127.0.0.1]) by mx0a-001b2d01.pphosted.com (PPS) with ESMTPS id 49v31cbxkm-1 (version=TLSv1.2 cipher=ECDHE-RSA-AES256-GCM-SHA384 bits=256 verify=NOT); Wed, 22 Oct 2025 14:43:39 +0000 (GMT) Received: from m0360072.ppops.net (m0360072.ppops.net [127.0.0.1]) by pps.reinject (8.18.1.12/8.18.0.8) with ESMTP id 59MEhcRZ006768; Wed, 22 Oct 2025 14:43:38 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 49v31cbxkh-1 (version=TLSv1.2 cipher=ECDHE-RSA-AES256-GCM-SHA384 bits=256 verify=NOT); Wed, 22 Oct 2025 14:43:38 +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 59MEOv7N002926; Wed, 22 Oct 2025 14:43:36 GMT Received: from smtprelay07.fra02v.mail.ibm.com ([9.218.2.229]) by ppma13.dal12v.mail.ibm.com (PPS) with ESMTPS id 49vqejgnrm-1 (version=TLSv1.2 cipher=ECDHE-RSA-AES256-GCM-SHA384 bits=256 verify=NOT); Wed, 22 Oct 2025 14:43:36 +0000 Received: from smtpav07.fra02v.mail.ibm.com (smtpav07.fra02v.mail.ibm.com [10.20.54.106]) by smtprelay07.fra02v.mail.ibm.com (8.14.9/8.14.9/NCO v10.0) with ESMTP id 59MEhX3o37028320 (version=TLSv1/SSLv3 cipher=DHE-RSA-AES256-GCM-SHA384 bits=256 verify=OK); Wed, 22 Oct 2025 14:43:33 GMT Received: from smtpav07.fra02v.mail.ibm.com (unknown [127.0.0.1]) by IMSVA (Postfix) with ESMTP id E9E3820040; Wed, 22 Oct 2025 14:43:32 +0000 (GMT) Received: from smtpav07.fra02v.mail.ibm.com (unknown [127.0.0.1]) by IMSVA (Postfix) with ESMTP id 83A6E2004B; Wed, 22 Oct 2025 14:43:32 +0000 (GMT) Received: from tuxmaker.lnxne.boe (unknown [9.152.85.9]) by smtpav07.fra02v.mail.ibm.com (Postfix) with ESMTP; Wed, 22 Oct 2025 14:43:32 +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 , 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 v11 10/15] unwind_user/sframe: Add support for outermost frame indication Date: Wed, 22 Oct 2025 16:43:21 +0200 Message-ID: <20251022144326.4082059-11-jremus@linux.ibm.com> X-Mailer: git-send-email 2.48.1 In-Reply-To: <20251022144326.4082059-1-jremus@linux.ibm.com> References: <20251022144326.4082059-1-jremus@linux.ibm.com> Precedence: bulk X-Mailing-List: linux-trace-kernel@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 Content-Transfer-Encoding: 8bit X-TM-AS-GCONF: 00 X-Proofpoint-ORIG-GUID: BRfWPx8QpkOpLG-aZRCA8NkTlnPIHAYu X-Proofpoint-Spam-Details-Enc: AW1haW4tMjUxMDE4MDAyMiBTYWx0ZWRfX0vSzKkDt73cM 3rLWH8RLkV7JHq4JXE+T653nLHx73jTvYwfVYtsKYV12ix9McS9Wf0jnwBg0tcNvV3/G/XKiOyK 1v7iXrlYUQ8RCah8QoxYReRaHZ3jAkbiB8mvA1wPqBNl+1ibIUXu0PeSySgplUJ7LMpssNZA2iW yqYnt5EUKSdT79kZ5tf2p41NxgFdMI90hW8ngYzBbMK7rN4W8qVuL7yFvHWMcKScgR74mIXcVfg JYzfsmEo8V7vdj7U4B2AGeewXng5iORiFzE60dWEBgUbDKq0QzrqAqh1lu1T/v7xoJ+mOZXM2va isN5F/b1qJyi8+qoQSBJGsXr83v4v2CNsmXeVnj7PEQWXYwZ5QaJoPS9HsqIPiPyL+G44Jiwux6 in+Su6An+kB17bcHLzp/dRlGyWHm3g== X-Proofpoint-GUID: o_CQcPWl_RPECQVJiKg9vKYUToiB23rx X-Authority-Analysis: v=2.4 cv=SKNPlevH c=1 sm=1 tr=0 ts=68f8ed9b cx=c_pps a=AfN7/Ok6k8XGzOShvHwTGQ==:117 a=AfN7/Ok6k8XGzOShvHwTGQ==:17 a=x6icFKpwvdMA: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=+jEqtf1s3R9VXZ0wqowq2kgwd+I=:19 a=jhqOcbufqs7Y1TYCrUUU:22 a=1CNFftbPRP8L7MoqJWF3:22 a=HkZW87K1Qel5hWWM3VKY:22 a=wa9RWnbW_A1YIeRBVszw:22 a=DXsff8QfwkrTrK3sU8N1:22 a=Z5ABNNGmrOfJ6cZ5bIyy:22 a=bWyr8ysk75zN3GCy5bjg:22 X-Proofpoint-Virus-Version: vendor=baseguard engine=ICAP:2.0.293,Aquarius:18.0.1121,Hydra:6.1.9,FMLib:17.12.80.40 definitions=2025-10-22_05,2025-10-13_01,2025-03-28_01 X-Proofpoint-Spam-Details: rule=outbound_notspam policy=outbound score=0 phishscore=0 malwarescore=0 suspectscore=0 clxscore=1015 priorityscore=1501 spamscore=0 impostorscore=0 bulkscore=0 lowpriorityscore=0 adultscore=0 classifier=typeunknown authscore=0 authtc= authcc= route=outbound adjust=0 reason=mlx scancount=1 engine=8.19.0-2510020000 definitions=main-2510180022 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. (Jens) 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 5536374e2a22..bc3e2eb00325 100644 --- a/kernel/unwind/sframe.c +++ b/kernel/unwind/sframe.c @@ -24,6 +24,7 @@ struct sframe_fre { s32 ra_off; s32 fp_off; u8 info; + bool ra_undefined; }; DEFINE_STATIC_SRCU(sframe_srcu); @@ -173,6 +174,7 @@ static __always_inline int __read_fre(struct sframe_section *sec, unsigned char offset_count, offset_size; s32 cfa_off, ra_off, fp_off; unsigned long cur = fre_addr; + bool ra_undefined = false; unsigned char addr_size; u32 ip_off; u8 info; @@ -191,7 +193,7 @@ static __always_inline int __read_fre(struct sframe_section *sec, UNSAFE_GET_USER_INC(info, cur, 1, Efault); offset_count = SFRAME_FRE_OFFSET_COUNT(info); offset_size = offset_size_enum_to_size(SFRAME_FRE_OFFSET_SIZE(info)); - if (!offset_count || !offset_size) + if (!offset_size) return -EFAULT; if (cur + (offset_count * offset_size) > sec->fres_end) @@ -199,6 +201,14 @@ static __always_inline int __read_fre(struct sframe_section *sec, fre->size = addr_size + 1 + (offset_count * offset_size); + if (!offset_count) { + cfa_off = 0; + ra_off = 0; + fp_off = 0; + ra_undefined = true; + goto done; + } + UNSAFE_GET_USER_INC(cfa_off, cur, offset_size, Efault); offset_count--; @@ -219,11 +229,13 @@ static __always_inline int __read_fre(struct sframe_section *sec, if (offset_count) return -EFAULT; +done: fre->ip_off = ip_off; fre->cfa_off = cfa_off; fre->ra_off = ra_off; fre->fp_off = fp_off; fre->info = info; + fre->ra_undefined = ra_undefined; return 0; @@ -285,6 +297,7 @@ static __always_inline int __find_fre(struct sframe_section *sec, frame->ra_off = fre->ra_off; frame->fp_off = fre->fp_off; frame->use_fp = SFRAME_FRE_CFA_BASE_REG_ID(fre->info) == SFRAME_BASE_REG_FP; + frame->outermost = fre->ra_undefined; return 0; } -- 2.48.1