From mboxrd@z Thu Jan 1 00:00:00 1970 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 85DF0566A; Thu, 5 Jun 2025 09:06:37 +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=1749114399; cv=none; b=Niw2G+MGPloJwevL3YGotHmSjrlVYAlaQR19AuRnWHu953TYuD2Jw7CdkDAAi05m8TnthjqqBXiQ9nAN7U0xJI4PQI2oBnKFerbBWA965q76NmzqFNV2XzAWj+FCubcH3hy4P+vPBhY2UI34HAkf28yLCakDMdJp8xdm4oz/IC4= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1749114399; c=relaxed/simple; bh=/shQMOR1zYdDdv8vlDhRoaEdJl02lBuH2es2PgKpYDw=; h=Message-ID:Date:MIME-Version:Subject:To:Cc:References:From: In-Reply-To:Content-Type; b=kDJppbleMl7g2tFHSbtUnRU/AOBeEXCbhNHdIScG+ZVEh7+zolfWNEQL51gTcixrp0w3ACpvAqmFZRxAZwJlTp1cQYGQy2VX15RHVb3LNkIWHUEAhXVQc69W/dtvnKC+UIigRXO2HXKwl8JFffuDMYJG9YDtafgJguwCmF7VfSo= 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=VIWSv99M; 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="VIWSv99M" Received: from pps.filterd (m0360083.ppops.net [127.0.0.1]) by mx0a-001b2d01.pphosted.com (8.18.1.2/8.18.1.2) with ESMTP id 554Na9ES025443; Thu, 5 Jun 2025 09:06:35 GMT DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=ibm.com; h=cc :content-transfer-encoding:content-type:date:from:in-reply-to :message-id:mime-version:references:subject:to; s=pp1; bh=RggBQk NjQmrOgTc9mJNXEsYOfIhymx08A05AmkZ32fA=; b=VIWSv99MKpVrS/3KffSt8E DcNdpcD0fnlt/fIeXBkOLmfcU+YyQWUizQB5j8xtzqu9Jg+5Gy3sTaG6O2zcVUAK kAmohvl0B45GY8lL8AQooVk5nYMEXiEUpK6eXB9a6Ueaucdxz4uzivqw4Vdg4iaO pm0AUG2oMZZ8DxsxLhF5CqqNyz9cub7QrHDVaY2sPI8NQJjvG7BKYWtUzJUNgBgM WBb2AoGWdNJu6YQ0/U2jDzf2zGyjmMxMtg096p0+pCMEUR07efpH11DsNZilkHk+ vFqm4O8yeTDZmDBFN2dxaaFlTAFXTme9oVo8ezol2usdHPG56LxZXqC0+0DiUaAw == 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 471geyyrrd-1 (version=TLSv1.2 cipher=ECDHE-RSA-AES256-GCM-SHA384 bits=256 verify=NOT); Thu, 05 Jun 2025 09:06:34 +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 55590M3Z024899; Thu, 5 Jun 2025 09:06:33 GMT Received: from smtprelay03.fra02v.mail.ibm.com ([9.218.2.224]) by ppma23.wdc07v.mail.ibm.com (PPS) with ESMTPS id 470dkmkx2j-1 (version=TLSv1.2 cipher=ECDHE-RSA-AES256-GCM-SHA384 bits=256 verify=NOT); Thu, 05 Jun 2025 09:06:33 +0000 Received: from smtpav04.fra02v.mail.ibm.com (smtpav04.fra02v.mail.ibm.com [10.20.54.103]) by smtprelay03.fra02v.mail.ibm.com (8.14.9/8.14.9/NCO v10.0) with ESMTP id 55596TAt48300326 (version=TLSv1/SSLv3 cipher=DHE-RSA-AES256-GCM-SHA384 bits=256 verify=OK); Thu, 5 Jun 2025 09:06:29 GMT Received: from smtpav04.fra02v.mail.ibm.com (unknown [127.0.0.1]) by IMSVA (Postfix) with ESMTP id 9F3F120040; Thu, 5 Jun 2025 09:06:29 +0000 (GMT) Received: from smtpav04.fra02v.mail.ibm.com (unknown [127.0.0.1]) by IMSVA (Postfix) with ESMTP id 4F6E72004D; Thu, 5 Jun 2025 09:06:29 +0000 (GMT) Received: from [9.152.224.132] (unknown [9.152.224.132]) by smtpav04.fra02v.mail.ibm.com (Postfix) with ESMTP; Thu, 5 Jun 2025 09:06:29 +0000 (GMT) Message-ID: <408922a2-ec1a-4e60-841a-90714a3310de@linux.ibm.com> Date: Thu, 5 Jun 2025 11:06:29 +0200 Precedence: bulk X-Mailing-List: linux-s390@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 User-Agent: Mozilla Thunderbird Subject: Re: [PATCH] s390/mm: Fix in_atomic() handling in do_secure_storage_access() To: Alexander Gordeev , Claudio Imbrenda Cc: Heiko Carstens , Janosch Frank , David Hildenbrand , Sven Schnelle , Vasily Gorbik , kvm@vger.kernel.org, linux-s390@vger.kernel.org, linux-kernel@vger.kernel.org References: <20250603134936.1314139-1-hca@linux.ibm.com> <20250604184855.44793208@p-imbrenda> <20250604194043.0ab9535e@p-imbrenda> Content-Language: en-US From: Christian Borntraeger In-Reply-To: Content-Type: text/plain; charset=UTF-8; format=flowed Content-Transfer-Encoding: 7bit X-TM-AS-GCONF: 00 X-Authority-Analysis: v=2.4 cv=Pq2TbxM3 c=1 sm=1 tr=0 ts=68415e1a cx=c_pps a=3Bg1Hr4SwmMryq2xdFQyZA==:117 a=3Bg1Hr4SwmMryq2xdFQyZA==:17 a=IkcTkHD0fZMA:10 a=6IFa9wvqVegA:10 a=VnNF1IyMAAAA:8 a=qs_iwHwmzb1svy77jOgA:9 a=QEXdDO2ut3YA:10 X-Proofpoint-Spam-Details-Enc: AW1haW4tMjUwNjA1MDA3OSBTYWx0ZWRfX56Aaz+6lp1sS mEOeYxehi2DphEuBbod0dYjowDACQZs7aQhdxpa8L0SpbLAby6DJJH9bbvZpKYAhh7P1MYha9Da sBrslJ+UFNr8nstx/WIOK/tYEmzIoZnpq142SUt3RBDM92Ae4i5ow7edrvUM+Sz28VNK5ZOqG+Q +LNgw00V67U/f4VUYp4Jn2dyfnC7yu9XmG/DQWbebkxwmrTNd1he5L7OG+63Ft/qVjahuhg6SJ9 jdF7Z+ku0UemEYPOFKNcLacnSM3n75o/8Pne2ElgTvwyFzMvzqzmcDzDjQRYAy1gCFFG2xQpDt0 e5zT8U1heI70tEGbwwBHyAdgTAWW3xVZGWRvIzfTv/ZskxOS4nbZn2BMNTbwbamC6CIP0FO/jgL M0c1JVOZzUbBE8uzDnI1Hyf5wEJ90botszjcGy+reLfXkDBFMiLi8M1kg5oeE0C7vDiaASJp X-Proofpoint-GUID: RjIhY-TYWY2ygrrA15FlHV_osAC84UCg X-Proofpoint-ORIG-GUID: RjIhY-TYWY2ygrrA15FlHV_osAC84UCg X-Proofpoint-Virus-Version: vendor=baseguard engine=ICAP:2.0.293,Aquarius:18.0.1099,Hydra:6.0.736,FMLib:17.12.80.40 definitions=2025-06-05_02,2025-06-03_02,2025-03-28_01 X-Proofpoint-Spam-Details: rule=outbound_notspam policy=outbound score=0 impostorscore=0 lowpriorityscore=0 clxscore=1015 malwarescore=0 mlxlogscore=703 phishscore=0 bulkscore=0 spamscore=0 suspectscore=0 priorityscore=1501 mlxscore=0 adultscore=0 classifier=spam authscore=0 authtc=n/a authcc= route=outbound adjust=0 reason=mlx scancount=1 engine=8.19.0-2505280000 definitions=main-2506050079 Am 05.06.25 um 11:04 schrieb Alexander Gordeev: > On Wed, Jun 04, 2025 at 07:40:43PM +0200, Claudio Imbrenda wrote: >>>>> This could trigger WARN_ON_ONCE() in handle_fault_error_nolock(): >>>>> >>>>> if (WARN_ON_ONCE(!si_code)) >>>>> si_code = SEGV_MAPERR; >>>>> >>>>> Would this warning be justified in this case (aka user_mode(regs) == >>>>> true)? >>>> >>>> I think so, because if we are in usermode, we should never trigger >>>> faulthandler_disabled() >>> >>> I think I do not get you. We are in a system call and also in_atomic(), >>> so faulthandler_disabled() is true and handle_fault_error_nolock(regs, 0) >>> is called (above). >> >> what is the psw in regs? >> is it not the one that was being used when the exception was triggered? > > Hmm, right. I assume is_kernel_fault() returns false not because > user_mode(regs) is true, but because we access the secondary AS. > > Still, to me it feels wrong to trigger that warning due to a user > process activity. But anyway: > > Acked-by: Alexander Gordeev Can we trigger a WARN from userspace?