From patchwork Thu Dec 1 07:10:18 2022 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Rohan McLure X-Patchwork-Id: 1710882 Return-Path: X-Original-To: incoming@patchwork.ozlabs.org Delivered-To: patchwork-incoming@legolas.ozlabs.org Authentication-Results: legolas.ozlabs.org; spf=pass (sender SPF authorized) smtp.mailfrom=lists.ozlabs.org (client-ip=112.213.38.117; helo=lists.ozlabs.org; envelope-from=linuxppc-dev-bounces+incoming=patchwork.ozlabs.org@lists.ozlabs.org; receiver=) Authentication-Results: legolas.ozlabs.org; dkim=fail reason="signature verification failed" (2048-bit key; unprotected) header.d=ibm.com header.i=@ibm.com header.a=rsa-sha256 header.s=pp1 header.b=M7wFZUnf; dkim-atps=neutral Received: from lists.ozlabs.org (lists.ozlabs.org [112.213.38.117]) (using TLSv1.3 with cipher TLS_AES_256_GCM_SHA384 (256/256 bits) key-exchange X25519 server-signature ECDSA (P-384)) (No client certificate requested) by legolas.ozlabs.org (Postfix) with ESMTPS id 4NN6ms4Zcbz23nS for ; Thu, 1 Dec 2022 18:15:56 +1100 (AEDT) Received: from boromir.ozlabs.org (localhost [IPv6:::1]) by lists.ozlabs.org (Postfix) with ESMTP id 4NN6mr1pnkz3bfF for ; Thu, 1 Dec 2022 18:15:56 +1100 (AEDT) Authentication-Results: lists.ozlabs.org; dkim=fail reason="signature verification failed" (2048-bit key; unprotected) header.d=ibm.com header.i=@ibm.com header.a=rsa-sha256 header.s=pp1 header.b=M7wFZUnf; dkim-atps=neutral X-Original-To: linuxppc-dev@lists.ozlabs.org Delivered-To: linuxppc-dev@lists.ozlabs.org Authentication-Results: lists.ozlabs.org; spf=pass (sender SPF authorized) smtp.mailfrom=linux.ibm.com (client-ip=148.163.158.5; helo=mx0b-001b2d01.pphosted.com; envelope-from=rmclure@linux.ibm.com; receiver=) Authentication-Results: lists.ozlabs.org; dkim=pass (2048-bit key; unprotected) header.d=ibm.com header.i=@ibm.com header.a=rsa-sha256 header.s=pp1 header.b=M7wFZUnf; dkim-atps=neutral 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 lists.ozlabs.org (Postfix) with ESMTPS id 4NN6gC0Zkdz3bbh for ; Thu, 1 Dec 2022 18:11:02 +1100 (AEDT) Received: from pps.filterd (m0098421.ppops.net [127.0.0.1]) by mx0a-001b2d01.pphosted.com (8.17.1.19/8.17.1.19) with ESMTP id 2B15fMtl020893; Thu, 1 Dec 2022 07:10:58 GMT DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=ibm.com; h=from : to : cc : subject : date : message-id : in-reply-to : references : content-transfer-encoding : mime-version; s=pp1; bh=Wkhhlw9qBYz7Uo7OGRwhX4jGVN29FqbpmGKdYVLMZvA=; b=M7wFZUnfe4Mgss9HYGZli7iCNbVE8CktnI487f0/WwVv0zx2kq0Zpak7WjaoxltdNWJz gRfa9w0HlH35K41lxbEQ8YLkW3FzAAJpmIkLsBbQ+e46w0MM+9kXJHqYPrxjFQFqOtTW kg6z0Fg1Z/axIRY7hWtpsl5q+svlPNZlH5drIiW79UjU4NHuESA40TNPfHxBE/KdZfh2 E8m6VrAHSLfZrKOzTxehCXd1BaE1KuszRBBn2OcPppv+kSBr1F8geqJr0HkodiDCsvld cbjvRldv8b6F1GPHLrjDjZRjLLd634DS+YyLRabJ/ubAOOggp+46S62XsX+jnJCFe0sL EA== Received: from pps.reinject (localhost [127.0.0.1]) by mx0a-001b2d01.pphosted.com (PPS) with ESMTPS id 3m6nyc2c0y-1 (version=TLSv1.2 cipher=ECDHE-RSA-AES256-GCM-SHA384 bits=256 verify=NOT); Thu, 01 Dec 2022 07:10:58 +0000 Received: from m0098421.ppops.net (m0098421.ppops.net [127.0.0.1]) by pps.reinject (8.17.1.5/8.17.1.5) with ESMTP id 2B15x4C8025934; Thu, 1 Dec 2022 07:10:57 GMT Received: from ppma06ams.nl.ibm.com (66.31.33a9.ip4.static.sl-reverse.com [169.51.49.102]) by mx0a-001b2d01.pphosted.com (PPS) with ESMTPS id 3m6nyc2c07-1 (version=TLSv1.2 cipher=ECDHE-RSA-AES256-GCM-SHA384 bits=256 verify=NOT); Thu, 01 Dec 2022 07:10:57 +0000 Received: from pps.filterd (ppma06ams.nl.ibm.com [127.0.0.1]) by ppma06ams.nl.ibm.com (8.16.1.2/8.16.1.2) with SMTP id 2B176RIE012742; Thu, 1 Dec 2022 07:10:55 GMT Received: from b06cxnps3074.portsmouth.uk.ibm.com (d06relay09.portsmouth.uk.ibm.com [9.149.109.194]) by ppma06ams.nl.ibm.com with ESMTP id 3m3a2hxy65-1 (version=TLSv1.2 cipher=ECDHE-RSA-AES256-GCM-SHA384 bits=256 verify=NOT); Thu, 01 Dec 2022 07:10:55 +0000 Received: from b06wcsmtp001.portsmouth.uk.ibm.com (b06wcsmtp001.portsmouth.uk.ibm.com [9.149.105.160]) by b06cxnps3074.portsmouth.uk.ibm.com (8.14.9/8.14.9/NCO v10.0) with ESMTP id 2B17Ar144391604 (version=TLSv1/SSLv3 cipher=DHE-RSA-AES256-GCM-SHA384 bits=256 verify=OK); Thu, 1 Dec 2022 07:10:53 GMT Received: from b06wcsmtp001.portsmouth.uk.ibm.com (unknown [127.0.0.1]) by IMSVA (Postfix) with ESMTP id 7FB90A4054; Thu, 1 Dec 2022 07:10:53 +0000 (GMT) Received: from b06wcsmtp001.portsmouth.uk.ibm.com (unknown [127.0.0.1]) by IMSVA (Postfix) with ESMTP id 2B0E0A405B; Thu, 1 Dec 2022 07:10:53 +0000 (GMT) Received: from ozlabs.au.ibm.com (unknown [9.192.253.14]) by b06wcsmtp001.portsmouth.uk.ibm.com (Postfix) with ESMTP; Thu, 1 Dec 2022 07:10:53 +0000 (GMT) Received: from civic.. (unknown [9.177.92.149]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by ozlabs.au.ibm.com (Postfix) with ESMTPSA id 8C75360366; Thu, 1 Dec 2022 18:10:49 +1100 (AEDT) From: Rohan McLure To: linuxppc-dev@lists.ozlabs.org Subject: [PATCH v5 6/7] powerpc/64e: Clear gprs on interrupt routine entry on Book3E Date: Thu, 1 Dec 2022 18:10:18 +1100 Message-Id: <20221201071019.1953023-6-rmclure@linux.ibm.com> X-Mailer: git-send-email 2.37.2 In-Reply-To: <20221201071019.1953023-1-rmclure@linux.ibm.com> References: <20221201071019.1953023-1-rmclure@linux.ibm.com> X-TM-AS-GCONF: 00 X-Proofpoint-ORIG-GUID: S6781FC7ErzjjF8xTHUJsKzAPpYBAKHv X-Proofpoint-GUID: GJQrC4EFjv55ZjEeNYdzlB5bFIGtktfv X-Proofpoint-UnRewURL: 0 URL was un-rewritten MIME-Version: 1.0 X-Proofpoint-Virus-Version: vendor=baseguard engine=ICAP:2.0.219,Aquarius:18.0.895,Hydra:6.0.545,FMLib:17.11.122.1 definitions=2022-12-01_04,2022-11-30_02,2022-06-22_01 X-Proofpoint-Spam-Details: rule=outbound_notspam policy=outbound score=0 clxscore=1015 impostorscore=0 bulkscore=0 adultscore=0 spamscore=0 phishscore=0 priorityscore=1501 lowpriorityscore=0 mlxscore=0 mlxlogscore=685 suspectscore=0 malwarescore=0 classifier=spam adjust=0 reason=mlx scancount=1 engine=8.12.0-2210170000 definitions=main-2212010048 X-BeenThere: linuxppc-dev@lists.ozlabs.org X-Mailman-Version: 2.1.29 Precedence: list List-Id: Linux on PowerPC Developers Mail List List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Cc: Rohan McLure , npiggin@gmail.com Errors-To: linuxppc-dev-bounces+incoming=patchwork.ozlabs.org@lists.ozlabs.org Sender: "Linuxppc-dev" Zero GPRS r14-r31 on entry into the kernel for interrupt sources to limit influence of user-space values in potential speculation gadgets. Prior to this commit, all other GPRS are reassigned during the common prologue to interrupt handlers and so need not be zeroised explicitly. This may be done safely, without loss of register state prior to the interrupt, as the common prologue saves the initial values of non-volatiles, which are unconditionally restored in interrupt_64.S. Mitigation defaults to enabled by INTERRUPT_SANITIZE_REGISTERS. Reviewed-by: Nicholas Piggin Signed-off-by: Rohan McLure --- Resubmitting patches as their own series after v6 partially merged: Link: https://lore.kernel.org/all/166488988686.779920.13794870102696416283.b4-ty@ellerman.id.au/t/ --- arch/powerpc/kernel/exceptions-64e.S | 4 ++-- 1 file changed, 2 insertions(+), 2 deletions(-) diff --git a/arch/powerpc/kernel/exceptions-64e.S b/arch/powerpc/kernel/exceptions-64e.S index 930e36099015..52431cb0c083 100644 --- a/arch/powerpc/kernel/exceptions-64e.S +++ b/arch/powerpc/kernel/exceptions-64e.S @@ -358,7 +358,6 @@ ret_from_mc_except: std r14,PACA_EXMC+EX_R14(r13); \ std r15,PACA_EXMC+EX_R15(r13) - /* Core exception code for all exceptions except TLB misses. */ #define EXCEPTION_COMMON_LVL(n, scratch, excf) \ exc_##n##_common: \ @@ -394,7 +393,8 @@ exc_##n##_common: \ std r12,STACK_FRAME_OVERHEAD-16(r1); /* mark the frame */ \ std r3,_TRAP(r1); /* set trap number */ \ std r0,RESULT(r1); /* clear regs->result */ \ - SAVE_NVGPRS(r1); + SAVE_NVGPRS(r1); \ + SANITIZE_NVGPRS(); /* minimise speculation influence */ #define EXCEPTION_COMMON(n) \ EXCEPTION_COMMON_LVL(n, SPRN_SPRG_GEN_SCRATCH, PACA_EXGEN)