From nobody Sat Feb 7 09:37:01 2026 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 EEDD827FB35; Tue, 27 Jan 2026 15:33:58 +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=1769528040; cv=none; b=FOdHhq01i3u3qg6P83Z/dNjwJm+5TlNviFvmCuD7HJd/BmNfqpuJGF7sHTgz2ZwiZ7yGERigIvJQImZYv/iR5Ox12YbH/H6FBpgy+FqLxO7ZPw7a5Ozccx9GRHyhx9/6eJt+Rv3ICZwDYt598rlnMb6J9PFBig+0tbgPtlZhAB0= ARC-Message-Signature: i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1769528040; c=relaxed/simple; bh=86jpirqaQmUPCyz8o+dsbMp2rt2TgCVsRD8m15jXVwo=; h=From:To:Cc:Subject:Date:Message-ID:In-Reply-To:References: MIME-Version; b=MGZabkAyIa+1qQZR4ZWiXWf/mNokxA3gSvYAdKEza83TugUD6GHylToxDpZq+SRy5nNzhp7Uv6D/vIWVSi8QQpdwdC/H3ggfzYZmd2kf3abclOt5HJvzBdaD6W71nX8JLm+ZWD/7kNErzg+SP7WIkTmKT9rE4HazDf/XCZQfsDs= 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=K+x4OCS3; 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="K+x4OCS3" Received: from pps.filterd (m0353729.ppops.net [127.0.0.1]) by mx0a-001b2d01.pphosted.com (8.18.1.2/8.18.1.2) with ESMTP id 60R80wYD010200; Tue, 27 Jan 2026 15:33:41 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=FZ8S4pktqaByy4bmM ZjsAmN/DAuj1dp0vk/8CjYYzGk=; b=K+x4OCS3ZZ75agk3mpGHGE2+vedZv/CpE sD1NjiKh/TlkmNpdhhlB4597f+J5FAktRHxoKV5rjdEIP20R2Q5lnWPvg/ZU98XX kXkox+i28VZnhlniPC0YSDJxJv8PAQQLozUZtACwwmpQP4Gh8b//3EDE8q9mA3Jl vGfI1svoATSlb8IfwCHLFXs6xy7wr5axAjMe9qKxt3cBoRe5JmpCZY2hjyToxa+4 rZfAd2dgWEoAEVifZz9fzH89S/eyHeNZcSCLuQ2Lo4nXMLbomIXb/OT9LOzW9OE9 RX60sOnQp9GDIb31c/rXzkBnV1KeZ35cS5ns7Ir4wn9QZ2S1NY/9A== Received: from pps.reinject (localhost [127.0.0.1]) by mx0a-001b2d01.pphosted.com (PPS) with ESMTPS id 4bvnrte437-1 (version=TLSv1.2 cipher=ECDHE-RSA-AES256-GCM-SHA384 bits=256 verify=NOT); Tue, 27 Jan 2026 15:33:41 +0000 (GMT) Received: from m0353729.ppops.net (m0353729.ppops.net [127.0.0.1]) by pps.reinject (8.18.1.12/8.18.0.8) with ESMTP id 60RFTbBk027291; Tue, 27 Jan 2026 15:33:40 GMT Received: from ppma23.wdc07v.mail.ibm.com (5d.69.3da9.ip4.static.sl-reverse.com [169.61.105.93]) by mx0a-001b2d01.pphosted.com (PPS) with ESMTPS id 4bvnrte42y-1 (version=TLSv1.2 cipher=ECDHE-RSA-AES256-GCM-SHA384 bits=256 verify=NOT); Tue, 27 Jan 2026 15:33:40 +0000 (GMT) Received: from pps.filterd (ppma23.wdc07v.mail.ibm.com [127.0.0.1]) by ppma23.wdc07v.mail.ibm.com (8.18.1.2/8.18.1.2) with ESMTP id 60RDnlDV026333; Tue, 27 Jan 2026 15:33:39 GMT Received: from smtprelay07.fra02v.mail.ibm.com ([9.218.2.229]) by ppma23.wdc07v.mail.ibm.com (PPS) with ESMTPS id 4bw9wk94jk-1 (version=TLSv1.2 cipher=ECDHE-RSA-AES256-GCM-SHA384 bits=256 verify=NOT); Tue, 27 Jan 2026 15:33:38 +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 60RFXZZW51118590 (version=TLSv1/SSLv3 cipher=DHE-RSA-AES256-GCM-SHA384 bits=256 verify=OK); Tue, 27 Jan 2026 15:33:35 GMT Received: from smtpav02.fra02v.mail.ibm.com (unknown [127.0.0.1]) by IMSVA (Postfix) with ESMTP id F24D720040; Tue, 27 Jan 2026 15:33:34 +0000 (GMT) Received: from smtpav02.fra02v.mail.ibm.com (unknown [127.0.0.1]) by IMSVA (Postfix) with ESMTP id AD4EB2004B; Tue, 27 Jan 2026 15:33:34 +0000 (GMT) Received: from tuxmaker.boeblingen.de.ibm.com (unknown [9.87.85.9]) by smtpav02.fra02v.mail.ibm.com (Postfix) with ESMTP; Tue, 27 Jan 2026 15:33:34 +0000 (GMT) From: Jens Remus To: linux-kernel@vger.kernel.org, linux-trace-kernel@vger.kernel.org, linux-s390@vger.kernel.org, bpf@vger.kernel.org, x86@kernel.org, Steven Rostedt Cc: Jens Remus , Heiko Carstens , Vasily Gorbik , Ilya Leoshkevich , 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 Subject: [RFC PATCH v1 5/5] s390/unwind_user: Enable signal frame unwinding of user space Date: Tue, 27 Jan 2026 16:33:31 +0100 Message-ID: <20260127153331.2902504-6-jremus@linux.ibm.com> X-Mailer: git-send-email 2.51.0 In-Reply-To: <20260127153331.2902504-1-jremus@linux.ibm.com> References: <20260127153331.2902504-1-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-Proofpoint-GUID: Egw92gpmw21Tk624x5Mdz0ym_tBI3ZKX X-Authority-Analysis: v=2.4 cv=Uptu9uwB c=1 sm=1 tr=0 ts=6978dad5 cx=c_pps a=3Bg1Hr4SwmMryq2xdFQyZA==:117 a=3Bg1Hr4SwmMryq2xdFQyZA==:17 a=vUbySO9Y5rIA:10 a=VkNPw1HP01LnGYTKEx00:22 a=VnNF1IyMAAAA:8 a=ZF5zZzGiEMQ9POZBm20A:9 X-Proofpoint-ORIG-GUID: CJduqsfu8ckaT3gi-0pqezvQAKTeBaJV X-Proofpoint-Spam-Details-Enc: AW1haW4tMjYwMTI3MDEyMSBTYWx0ZWRfX8rVLt5Xl7ClL FJE/3s2Blo2OpURe8yq6VPsvBVe8Vm9wYW7VMsTOkl+3R8iMgDwIfO0HawD+LZFSHhIbtjGE6rw ENwL1lXVV95OGhAdVze4bcQHr/0nfstMuJW3KARqIkIVh2JoUD2r4iRLdoELlTDkiTTJem7r4C9 mM9xRSTJJUSyEs4szmvbxYlNX0oM+uBDQhkOs+5OIPQpgu/ZNlAzPHaNghd688/H156RYgnNfGk bzqhhciShiGtDxjAHq0JOHwG8FiE5LVbeXl/Fu/lah2CHn9NfpeTGearhtnSgTqzHg0gx9qj5yH dHmBDjjvhdSlUrHEFXBjIPR3JwaGWFIG5VMjkeVNL9jHQ7LqFTk7S4QlCSpDI3hXCikONv41kqk fwQFsl+iaZ4zbycUYSFIPlVZeTnvpRBN+cdvgSdme6f8PtJkDyWI9NPuzx0zyovY9fg2mgKNoD8 E/zXH/m+B4NHAgarMIw== X-Proofpoint-Virus-Version: vendor=baseguard engine=ICAP:2.0.293,Aquarius:18.0.1121,Hydra:6.1.51,FMLib:17.12.100.49 definitions=2026-01-27_03,2026-01-27_02,2025-10-01_01 X-Proofpoint-Spam-Details: rule=outbound_notspam policy=outbound score=0 malwarescore=0 priorityscore=1501 clxscore=1015 lowpriorityscore=0 phishscore=0 adultscore=0 impostorscore=0 bulkscore=0 spamscore=0 suspectscore=0 classifier=typeunknown authscore=0 authtc= authcc= route=outbound adjust=0 reason=mlx scancount=1 engine=8.19.0-2601150000 definitions=main-2601270121 Content-Type: text/plain; charset="utf-8" Provide a s390-specific implementation of unwind_user_signal_next(), that unwinds from a (RT) signal frame. Signed-off-by: Jens Remus --- arch/s390/include/asm/unwind_user.h | 57 +++++++++++++++++++++++++++++ 1 file changed, 57 insertions(+) diff --git a/arch/s390/include/asm/unwind_user.h b/arch/s390/include/asm/un= wind_user.h index a7b97ea01c26..8f5524a24ae1 100644 --- a/arch/s390/include/asm/unwind_user.h +++ b/arch/s390/include/asm/unwind_user.h @@ -7,6 +7,7 @@ #include #include #include +#include #include #include =20 @@ -67,6 +68,62 @@ static inline int arch_unwind_user_get_reg(unsigned long= *val, } #define unwind_user_get_reg arch_unwind_user_get_reg =20 +#define SVC_OPCODE 0x0a +#define INSN_SVC_SIGRETURN ((SVC_OPCODE << 8) | __NR_sigreturn) +#define INSN_SVC_RT_SIGRETURN ((SVC_OPCODE << 8) | __NR_rt_sigreturn) + +static inline int unwind_user_signal_next(struct unwind_user_state *state) +{ + unsigned short insn; + const _sigregs __user *sr; + unsigned long sp, fp, ra; + + /* ABI requires IP to be 2-byte aligned. */ + if (state->ip & 1) + return -EINVAL; + + if (__get_user(insn, (unsigned short __user *)state->ip)) + return -EINVAL; + + /* + * A signal frame has the instruction pointer pointing to + * svc $__NR_sigreturn or svc $__NR_rt_sigreturn + */ + switch (insn) { + case INSN_SVC_SIGRETURN: + /* New-style non-RT frame. */ + const struct sigframe __user *sf; + + sf =3D (struct sigframe __user *)state->sp; + if (__get_user(sr, (_sigregs __user **)&sf->sc.sregs)) + return -EINVAL; + break; + case INSN_SVC_RT_SIGRETURN: + /* New-style RT frame. */ + const struct rt_sigframe __user *rt_sf; + + rt_sf =3D (struct rt_sigframe __user *)state->sp; + sr =3D (_sigregs __user *)&rt_sf->uc.uc_mcontext; + break; + default: + return -EINVAL; + } + + if (__get_user(sp, (unsigned long __user *)&sr->regs.gprs[15])) + return -EINVAL; + if (__get_user(fp, (unsigned long __user *)&sr->regs.gprs[11])) + return -EINVAL; + if (__get_user(ra, (unsigned long __user *)&sr->regs.psw.addr)) + return -EINVAL; + + state->ip =3D ra; + state->sp =3D sp; + state->fp =3D fp; + state->topmost =3D false; + return 0; +} +#define unwind_user_signal_next unwind_user_signal_next + #endif /* CONFIG_UNWIND_USER */ =20 #ifdef CONFIG_HAVE_UNWIND_USER_FP --=20 2.51.0