From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: X-Spam-Checker-Version: SpamAssassin 3.4.0 (2014-02-07) on aws-us-west-2-korg-lkml-1.web.codeaurora.org Received: from kanga.kvack.org (kanga.kvack.org [205.233.56.17]) (using TLSv1 with cipher DHE-RSA-AES256-SHA (256/256 bits)) (No client certificate requested) by smtp.lore.kernel.org (Postfix) with ESMTPS id AC239CD342F for ; Tue, 5 May 2026 12:18:16 +0000 (UTC) Received: by kanga.kvack.org (Postfix) id CEDDD6B0088; Tue, 5 May 2026 08:18:12 -0400 (EDT) Received: by kanga.kvack.org (Postfix, from userid 40) id C76B46B0093; Tue, 5 May 2026 08:18:12 -0400 (EDT) X-Delivered-To: int-list-linux-mm@kvack.org Received: by kanga.kvack.org (Postfix, from userid 63042) id B16B56B0088; Tue, 5 May 2026 08:18:12 -0400 (EDT) X-Delivered-To: linux-mm@kvack.org Received: from relay.hostedemail.com (smtprelay0010.hostedemail.com [216.40.44.10]) by kanga.kvack.org (Postfix) with ESMTP id 88BEC6B0092 for ; Tue, 5 May 2026 08:18:12 -0400 (EDT) Received: from smtpin23.hostedemail.com (lb01a-stub [10.200.18.249]) by unirelay05.hostedemail.com (Postfix) with ESMTP id 4AA35403E6 for ; Tue, 5 May 2026 12:18:12 +0000 (UTC) X-FDA: 84733268424.23.4608ED6 Received: from mx0a-001b2d01.pphosted.com (mx0a-001b2d01.pphosted.com [148.163.156.1]) by imf25.hostedemail.com (Postfix) with ESMTP id A0266A0002 for ; Tue, 5 May 2026 12:18:09 +0000 (UTC) Authentication-Results: imf25.hostedemail.com; dkim=pass header.d=ibm.com header.s=pp1 header.b=VEwxoKQy; spf=pass (imf25.hostedemail.com: domain of jremus@linux.ibm.com designates 148.163.156.1 as permitted sender) smtp.mailfrom=jremus@linux.ibm.com; dmarc=pass (policy=none) header.from=ibm.com ARC-Message-Signature: i=1; a=rsa-sha256; c=relaxed/relaxed; d=hostedemail.com; s=arc-20220608; t=1777983489; h=from:from:sender:reply-to:subject:subject:date:date: message-id:message-id:to:to:cc:cc:mime-version:mime-version: content-type:content-transfer-encoding:content-transfer-encoding: in-reply-to:in-reply-to:references:references:dkim-signature; bh=1rPRr3FZStWFGzetx6++VNjJW1FkjSSD795lGjO3e+g=; b=Ta5hUpQl16AIj9s9Kp9Lg+qm5fCCojndps6cOSb5bjg1gUDxSk/4EbrxJwvPG0nQyjiYX5 tP9sRrVAHYPkG5Ube7WnVoG8eyyg6QphtrP8Vc7iohcnHOUe+4i477o34mky6YnTw6sCaa 1Za0YlYcdJW7OQqUCh7CJeYNmebF8Cc= ARC-Authentication-Results: i=1; imf25.hostedemail.com; dkim=pass header.d=ibm.com header.s=pp1 header.b=VEwxoKQy; spf=pass (imf25.hostedemail.com: domain of jremus@linux.ibm.com designates 148.163.156.1 as permitted sender) smtp.mailfrom=jremus@linux.ibm.com; dmarc=pass (policy=none) header.from=ibm.com ARC-Seal: i=1; s=arc-20220608; d=hostedemail.com; t=1777983489; a=rsa-sha256; cv=none; b=RDzJJUWsjBbz73zns7yV70lNI0vozEUlNdwbhvRonwyLiDPsjmI4/khDc1DnfgLAVMKebI Wk39HFediYZ8chFk3uL/FjkFPeGQOb//b34FCric3LbryCnWvjBSlQk+5BLixJfKxmiSUT BTlExpKjGcDuaOA9eF6k1LR3BKSDrcY= Received: from pps.filterd (m0360083.ppops.net [127.0.0.1]) by mx0a-001b2d01.pphosted.com (8.18.1.11/8.18.1.11) with ESMTP id 6457XVQv3464145; Tue, 5 May 2026 12:17:30 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=1rPRr3FZStWFGzetx 6++VNjJW1FkjSSD795lGjO3e+g=; b=VEwxoKQytBh8r2anKmrQqsD/fQrUCoyYI dPEgpHAorlGbTKN9hFnqiHfk/Y70Z7kIWHvhdgrbZpSi4YaocTbjDKQqkv6lQWXL 1o0+YDWR+sKsS/D/CcTo7avul1PUaW9nRyzLfsqTn1zBmM69KJpPyq+C7woDYKdN fcQRoxnIEWlCLJZM9kW2MrJB9BZtw+FmW8jW73vfP4fRPIkPcBtS8TRGL69vMoz7 Vj89YJgsQw7Sd8KiewtLXRLG1ZLGtU18ROXSc1iTrGLOctoRq+2BOjp/mjPbUVh5 MWNl3YnG8wqTMpFdrhyD/gKO4UfR7SmvWmh7J/4OBUyNEikLfXTog== Received: from ppma12.dal12v.mail.ibm.com (dc.9e.1632.ip4.static.sl-reverse.com [50.22.158.220]) by mx0a-001b2d01.pphosted.com (PPS) with ESMTPS id 4dw9v7bj9h-1 (version=TLSv1.2 cipher=ECDHE-RSA-AES256-GCM-SHA384 bits=256 verify=NOT); Tue, 05 May 2026 12:17:29 +0000 (GMT) Received: from pps.filterd (ppma12.dal12v.mail.ibm.com [127.0.0.1]) by ppma12.dal12v.mail.ibm.com (8.18.1.7/8.18.1.7) with ESMTP id 645C9a40030210; Tue, 5 May 2026 12:17:28 GMT Received: from smtprelay01.fra02v.mail.ibm.com ([9.218.2.227]) by ppma12.dal12v.mail.ibm.com (PPS) with ESMTPS id 4dwukq9nmn-1 (version=TLSv1.2 cipher=ECDHE-RSA-AES256-GCM-SHA384 bits=256 verify=NOT); Tue, 05 May 2026 12:17:28 +0000 (GMT) Received: from smtpav06.fra02v.mail.ibm.com (smtpav06.fra02v.mail.ibm.com [10.20.54.105]) by smtprelay01.fra02v.mail.ibm.com (8.14.9/8.14.9/NCO v10.0) with ESMTP id 645CHPVF59375896 (version=TLSv1/SSLv3 cipher=DHE-RSA-AES256-GCM-SHA384 bits=256 verify=OK); Tue, 5 May 2026 12:17:25 GMT Received: from smtpav06.fra02v.mail.ibm.com (unknown [127.0.0.1]) by IMSVA (Postfix) with ESMTP id 322A42004B; Tue, 5 May 2026 12:17:25 +0000 (GMT) Received: from smtpav06.fra02v.mail.ibm.com (unknown [127.0.0.1]) by IMSVA (Postfix) with ESMTP id C98F42004E; Tue, 5 May 2026 12:17:24 +0000 (GMT) Received: from tuxmaker.boeblingen.de.ibm.com (unknown [9.87.85.9]) by smtpav06.fra02v.mail.ibm.com (Postfix) with ESMTP; Tue, 5 May 2026 12:17:24 +0000 (GMT) From: Jens Remus To: linux-kernel@vger.kernel.org, linux-trace-kernel@vger.kernel.org, x86@kernel.org, Steven Rostedt , Josh Poimboeuf , Indu Bhagat , Peter Zijlstra , Dylan Hatch , Thomas Gleixner , Ingo Molnar , Borislav Petkov , Dave Hansen , "H. Peter Anvin" , Mathieu Desnoyers , Kees Cook , Sam James Cc: Jens Remus , bpf@vger.kernel.org, linux-mm@kvack.org, Namhyung Kim , Andrii Nakryiko , "Jose E. Marchesi" , Beau Belgrave , Florian Weimer , "Carlos O'Donell" , Masami Hiramatsu , Jiri Olsa , Arnaldo Carvalho de Melo , Andrew Morton , David Hildenbrand , Lorenzo Stoakes , "Liam R. Howlett" , Vlastimil Babka , Mike Rapoport , Suren Baghdasaryan , Michal Hocko , Heiko Carstens , Vasily Gorbik , Ilya Leoshkevich Subject: [PATCH v14 09/19] unwind_user/sframe: Add support for outermost frame indication Date: Tue, 5 May 2026 14:17:08 +0200 Message-ID: <20260505121718.3572346-10-jremus@linux.ibm.com> X-Mailer: git-send-email 2.51.0 In-Reply-To: <20260505121718.3572346-1-jremus@linux.ibm.com> References: <20260505121718.3572346-1-jremus@linux.ibm.com> MIME-Version: 1.0 Content-Transfer-Encoding: 8bit X-TM-AS-GCONF: 00 X-Proofpoint-Reinject: loops=2 maxloops=12 X-Proofpoint-Spam-Details-Enc: AW1haW4tMjYwNTA1MDExNCBTYWx0ZWRfXxs+poCAAGGNG 9Cfil+KpyvOWZ9eNrzo7p0DMXBFB8ddw/Z1jToIBMfBbF8gMOySE1DKHJWcGx47Gnac7WNDTiLo taNPOzcwB6Y8H6i8+1Pp4KPU6O2MUhFcCVbjeAmZURahIZN00aaJLb84ENmOF9mGSz+ks67MlTr rWIEqS/rjtv0J3bSVM1foQruayIKEyaxqJNlMCE5TMuK5spshFERy06ksgWNkD9fIzJybSvy8B3 ewWKJrKeorztqyjQ5ewij1YeHGFgGAgz/tqg52Kodd3NY4+bhgFswOXORS6TxaC/pufO+nVvMNa lvDsil9mJNjZR2uQAp/BAI5qeJIaCVQtOqPedhVQXoftsOrMd2EDrjECVrxiqBzenGD4t2J7Ncu CisLkq4sGFxUfvR9G99vD6Ar6DfjXVzC1S5QvuSL4Y/xZu+Qjhz09vn8ebdNyklOCvsy4Qs4CeP 2aUlUKu8+wPP2shbgRw== X-Proofpoint-GUID: efVzNbBCZREIKW4fO6gioglIN0VcT-tB X-Proofpoint-ORIG-GUID: BJSUMIXg6C-mMKI5aio-_pcfAq0a41Zm X-Authority-Analysis: v=2.4 cv=eu/vCIpX c=1 sm=1 tr=0 ts=69f9dfda cx=c_pps a=bLidbwmWQ0KltjZqbj+ezA==:117 a=bLidbwmWQ0KltjZqbj+ezA==:17 a=NGcC8JguVDcA:10 a=VkNPw1HP01LnGYTKEx00:22 a=RnoormkPH1_aCDwRdu11:22 a=iQ6ETzBq9ecOQQE5vZCe:22 a=pGLkceISAAAA:8 a=VnNF1IyMAAAA:8 a=U72JrVpwKSe1qDC-WCIA:9 X-Proofpoint-Virus-Version: vendor=baseguard engine=ICAP:2.0.293,Aquarius:18.0.1143,Hydra:6.1.51,FMLib:17.12.100.49 definitions=2026-05-05_02,2026-04-30_02,2025-10-01_01 X-Proofpoint-Spam-Details: rule=outbound_notspam policy=outbound score=0 priorityscore=1501 phishscore=0 lowpriorityscore=0 clxscore=1011 adultscore=0 suspectscore=0 malwarescore=0 bulkscore=0 impostorscore=0 spamscore=0 classifier=typeunknown authscore=0 authtc= authcc= route=outbound adjust=0 reason=mlx scancount=1 engine=8.22.0-2604200000 definitions=main-2605050114 X-Stat-Signature: c9rktnm5oo88xbcnkgzy3fd8oauo538a X-Rspamd-Server: rspam01 X-Rspamd-Queue-Id: A0266A0002 X-Rspam-User: X-HE-Tag: 1777983489-932625 X-HE-Meta: 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 hAVv039U 4RvlcrLj8lr8n3poSZdR22YxqY7va2KZ0Ml4necCN07If/LqWY1jOI+8nOk6QmxBHizh1MyGyGf8DITVktezaofBg5pIE/WngV7+s2gbeVENGCf214M8Er9agUqBjQXcbTVP7xPh1LtY7qVYwTPL1DLJEvz5+mjk5UPnMCGeQaO/C52jQqhooVYU5avDFyX0OIRL2rFcTQyP6/SQuskZPkSxzsuHW/iSh1KHS/XfVV0v/xteDPBad/wsp87DN9xdMypI3/qWtIhCtLBpWwl+FBv5yBz9vNp1uiADfG4+O3Y5Imjf0qONnb0laBcPU/IySdi+2/HEMenu27WsMa3HFaTaWjO3bFCRpNoLK1VpPuKIfcMj11HDohPvNrg== Sender: owner-linux-mm@kvack.org Precedence: bulk X-Loop: owner-majordomo@kvack.org List-ID: List-Subscribe: List-Unsubscribe: SFrame may represent an undefined return address (RA) as SFrame FRE without any offsets as indication for an outermost frame. Reviewed-by: Indu Bhagat Signed-off-by: Jens Remus --- kernel/unwind/sframe.c | 15 ++++++++++++++- kernel/unwind/sframe.h | 1 + 2 files changed, 15 insertions(+), 1 deletion(-) diff --git a/kernel/unwind/sframe.c b/kernel/unwind/sframe.c index c60aa527984a..9c755965ab83 100644 --- a/kernel/unwind/sframe.c +++ b/kernel/unwind/sframe.c @@ -218,7 +218,7 @@ static __always_inline int __read_fre(struct sframe_section *sec, UNSAFE_GET_USER_INC(info, cur, 1, Efault); dataword_count = SFRAME_V3_FRE_DATAWORD_COUNT(info); dataword_size = dataword_size_enum_to_size(SFRAME_V3_FRE_DATAWORD_SIZE(info)); - if (!dataword_count || !dataword_size) + if (!dataword_size) return -EFAULT; if (cur + (dataword_count * dataword_size) > sec->fres_end) @@ -228,6 +228,17 @@ static __always_inline int __read_fre(struct sframe_section *sec, if (fde_type != SFRAME_FDE_TYPE_DEFAULT) return -EFAULT; + if (!dataword_count) { + /* + * A FRE without data words indicates RA undefined / + * outermost frame. + */ + cfa_off = 0; + ra_off = 0; + fp_off = 0; + goto done; + } + UNSAFE_GET_USER_INC(cfa_off, cur, dataword_size, Efault); dataword_count--; @@ -248,6 +259,7 @@ static __always_inline int __read_fre(struct sframe_section *sec, if (dataword_count) return -EFAULT; +done: fre->size = addr_size + 1 + (dataword_count * dataword_size); fre->ip_off = ip_off; fre->cfa_off = cfa_off; @@ -314,6 +326,7 @@ 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_V3_FRE_CFA_BASE_REG_ID(fre->info) == SFRAME_BASE_REG_FP; + frame->outermost = SFRAME_V3_FRE_RA_UNDEFINED_P(fre->info); return 0; } diff --git a/kernel/unwind/sframe.h b/kernel/unwind/sframe.h index fc2908e92c7b..ed111fd0d702 100644 --- a/kernel/unwind/sframe.h +++ b/kernel/unwind/sframe.h @@ -77,5 +77,6 @@ struct sframe_fda_v3 { #define SFRAME_V3_FRE_DATAWORD_COUNT(info) (((info) >> 1) & 0xf) #define SFRAME_V3_FRE_DATAWORD_SIZE(info) (((info) >> 5) & 0x3) #define SFRAME_V3_AARCH64_FRE_MANGLED_RA_P(info) (((info) >> 7) & 0x1) +#define SFRAME_V3_FRE_RA_UNDEFINED_P(info) (SFRAME_V3_FRE_DATAWORD_COUNT(info) == 0) #endif /* _SFRAME_H */ -- 2.51.0