From patchwork Thu Sep 21 02:37:30 2023 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Bjorn Andersson X-Patchwork-Id: 13393601 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 vger.kernel.org (vger.kernel.org [23.128.96.18]) by smtp.lore.kernel.org (Postfix) with ESMTP id D490FCD4941 for ; Thu, 21 Sep 2023 02:37:54 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S229445AbjIUCh5 (ORCPT ); Wed, 20 Sep 2023 22:37:57 -0400 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:43136 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S229550AbjIUCh4 (ORCPT ); Wed, 20 Sep 2023 22:37:56 -0400 Received: from mx0a-0031df01.pphosted.com (mx0a-0031df01.pphosted.com [205.220.168.131]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id 0A915D7; Wed, 20 Sep 2023 19:37:51 -0700 (PDT) Received: from pps.filterd (m0279863.ppops.net [127.0.0.1]) by mx0a-0031df01.pphosted.com (8.17.1.19/8.17.1.19) with ESMTP id 38L1kmST024787; Thu, 21 Sep 2023 02:37:45 GMT DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=quicinc.com; h=from : date : subject : mime-version : content-type : content-transfer-encoding : message-id : references : in-reply-to : to : cc; s=qcppdkim1; bh=nBccwF1AJjDJHOkO9saAtELKx+a1Lz8POTJOCADT7jA=; b=UAxV89vHiCNO9eYM5jXfkK40wREPFI2WhWcpV9gSe24KEYlG0NU0PbMJ/7aJiVnmeifF QoqjfneCoi3N4UOguC+D0GdklAPHEHAdrRewhx6Re3KQm5v/NqkUgjCSKv5mejPIG0aZ 4vX/jTsmJJAZdK1r8OqOzcmdo9MayEJj+ru2o3HV2mOIYHag53pnTA7sZjDIvJoyAr0Z qLiLxaYzn5EfMJjGjHP7TDJX55/9ZMKeeGy07T4x4M3HbDP4EeC1whI9iIHPoAJmO3Sb 6EaskQhq+MQplH6XRI7Opohzeu4c1tTAVcaWXrzj42WkNKvdyvqbtGOm5FOQPq3tmhxa 4w== Received: from nalasppmta01.qualcomm.com (Global_NAT1.qualcomm.com [129.46.96.20]) by mx0a-0031df01.pphosted.com (PPS) with ESMTPS id 3t891c0cre-1 (version=TLSv1.2 cipher=ECDHE-RSA-AES256-GCM-SHA384 bits=256 verify=NOT); Thu, 21 Sep 2023 02:37:45 +0000 Received: from nalasex01c.na.qualcomm.com (nalasex01c.na.qualcomm.com [10.47.97.35]) by NALASPPMTA01.qualcomm.com (8.17.1.5/8.17.1.5) with ESMTPS id 38L2bi9i020704 (version=TLSv1.2 cipher=ECDHE-RSA-AES256-GCM-SHA384 bits=256 verify=NOT); Thu, 21 Sep 2023 02:37:44 GMT Received: from hu-bjorande-lv.qualcomm.com (10.49.16.6) by nalasex01c.na.qualcomm.com (10.47.97.35) with Microsoft SMTP Server (version=TLS1_2, cipher=TLS_ECDHE_RSA_WITH_AES_256_GCM_SHA384) id 15.2.1118.30; Wed, 20 Sep 2023 19:37:44 -0700 From: Bjorn Andersson Date: Wed, 20 Sep 2023 19:37:30 -0700 Subject: [PATCH v3 1/3] dt-bindings: reserved-memory: rmtfs: Allow guard pages MIME-Version: 1.0 Message-ID: <20230920-rmtfs-mem-guard-pages-v3-1-305b37219b78@quicinc.com> References: <20230920-rmtfs-mem-guard-pages-v3-0-305b37219b78@quicinc.com> In-Reply-To: <20230920-rmtfs-mem-guard-pages-v3-0-305b37219b78@quicinc.com> To: Andy Gross , Bjorn Andersson , Konrad Dybcio , Rob Herring , Krzysztof Kozlowski , Conor Dooley CC: , , , Bjorn Andersson X-Mailer: b4 0.12.0 X-Developer-Signature: v=1; a=ed25519-sha256; t=1695263863; l=1847; i=quic_bjorande@quicinc.com; s=20230915; h=from:subject:message-id; bh=xlRIelsN06YllMR6zQavDKa2EffnSwCF78u2DTrHj0w=; b=GyA4H0nGIEhcJOitilg5PSb/hOQlK+YMuj77kq8z5ef+diag1/IpNh1iG9+b0y2GTeJcpeMTbE9R KU4I732mCOfUBVGkBBZEdClKIEHyO2rhCWTdAwGp1qO9ZhsoCXi0 X-Developer-Key: i=quic_bjorande@quicinc.com; a=ed25519; pk=VkhObtljigy9k0ZUIE1Mvr0Y+E1dgBEH9WoLQnUtbIM= X-Originating-IP: [10.49.16.6] X-ClientProxiedBy: nalasex01c.na.qualcomm.com (10.47.97.35) To nalasex01c.na.qualcomm.com (10.47.97.35) X-QCInternal: smtphost X-Proofpoint-Virus-Version: vendor=nai engine=6200 definitions=5800 signatures=585085 X-Proofpoint-GUID: A4RG7nEGIcse6EKfjJv7rMQW7vhGoffc X-Proofpoint-ORIG-GUID: A4RG7nEGIcse6EKfjJv7rMQW7vhGoffc X-Proofpoint-Virus-Version: vendor=baseguard engine=ICAP:2.0.267,Aquarius:18.0.980,Hydra:6.0.601,FMLib:17.11.176.26 definitions=2023-09-20_14,2023-09-20_01,2023-05-22_02 X-Proofpoint-Spam-Details: rule=outbound_notspam policy=outbound score=0 spamscore=0 impostorscore=0 malwarescore=0 suspectscore=0 phishscore=0 priorityscore=1501 clxscore=1015 bulkscore=0 mlxscore=0 mlxlogscore=814 adultscore=0 lowpriorityscore=0 classifier=spam adjust=0 reason=mlx scancount=1 engine=8.12.0-2308100000 definitions=main-2309210021 Precedence: bulk List-ID: X-Mailing-List: linux-arm-msm@vger.kernel.org On some Qualcomm platforms the firwmare, or hardware, does not gracefully handle memory protection of the rmtfs memory region when placed adjacent to other protected region. Some DeviceTree authors have worked around this issue by explicitly reserving the space around the region, but this prevents such author to use rely on the OS to place the region, through the use of "size" (instead of a fixed location). Introduce a flag to indicate that guard pages need be carved at the beginning and end of the memory region. The user shall account for the two 4k blocks in the defined size. Signed-off-by: Bjorn Andersson Reviewed-by: Krzysztof Kozlowski --- .../devicetree/bindings/reserved-memory/qcom,rmtfs-mem.yaml | 11 +++++++++++ 1 file changed, 11 insertions(+) diff --git a/Documentation/devicetree/bindings/reserved-memory/qcom,rmtfs-mem.yaml b/Documentation/devicetree/bindings/reserved-memory/qcom,rmtfs-mem.yaml index bab982f00485..2d7be508c5a0 100644 --- a/Documentation/devicetree/bindings/reserved-memory/qcom,rmtfs-mem.yaml +++ b/Documentation/devicetree/bindings/reserved-memory/qcom,rmtfs-mem.yaml @@ -26,6 +26,17 @@ properties: description: > identifier of the client to use this region for buffers + qcom,use-guard-pages: + type: boolean + description: > + Indicates that the firmware, or hardware, does not gracefully handle + memory protection of this region when placed adjacent to other protected + memory regions, and that padding around the used portion of the memory + region is necessary. + + When this is set, the first and last 4kB should be left unused, and the + effective size of the region will thereby shrink with 8kB. + qcom,vmid: $ref: /schemas/types.yaml#/definitions/uint32-array description: > From patchwork Thu Sep 21 02:37:31 2023 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Bjorn Andersson X-Patchwork-Id: 13393603 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 vger.kernel.org (vger.kernel.org [23.128.96.18]) by smtp.lore.kernel.org (Postfix) with ESMTP id 6CDBACD4942 for ; Thu, 21 Sep 2023 02:37:55 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S229594AbjIUCh6 (ORCPT ); Wed, 20 Sep 2023 22:37:58 -0400 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:43150 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S229534AbjIUCh4 (ORCPT ); Wed, 20 Sep 2023 22:37:56 -0400 Received: from mx0a-0031df01.pphosted.com (mx0a-0031df01.pphosted.com [205.220.168.131]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id 35C1EE4; Wed, 20 Sep 2023 19:37:51 -0700 (PDT) Received: from pps.filterd (m0279862.ppops.net [127.0.0.1]) by mx0a-0031df01.pphosted.com (8.17.1.19/8.17.1.19) with ESMTP id 38L2ETRR004317; 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Thu, 21 Sep 2023 02:37:44 GMT Received: from hu-bjorande-lv.qualcomm.com (10.49.16.6) by nalasex01c.na.qualcomm.com (10.47.97.35) with Microsoft SMTP Server (version=TLS1_2, cipher=TLS_ECDHE_RSA_WITH_AES_256_GCM_SHA384) id 15.2.1118.30; Wed, 20 Sep 2023 19:37:44 -0700 From: Bjorn Andersson Date: Wed, 20 Sep 2023 19:37:31 -0700 Subject: [PATCH v3 2/3] soc: qcom: rmtfs: Support discarding guard pages MIME-Version: 1.0 Message-ID: <20230920-rmtfs-mem-guard-pages-v3-2-305b37219b78@quicinc.com> References: <20230920-rmtfs-mem-guard-pages-v3-0-305b37219b78@quicinc.com> In-Reply-To: <20230920-rmtfs-mem-guard-pages-v3-0-305b37219b78@quicinc.com> To: Andy Gross , Bjorn Andersson , Konrad Dybcio , Rob Herring , Krzysztof Kozlowski , Conor Dooley CC: , , , Bjorn Andersson X-Mailer: b4 0.12.0 X-Developer-Signature: v=1; a=ed25519-sha256; t=1695263863; l=1416; i=quic_bjorande@quicinc.com; s=20230915; h=from:subject:message-id; bh=QJw72O7i7ZmFiiHvUXcqqtPd/U+RD0Qw3QJSkoRMKPE=; b=FLlS4/QOwYvniUnTEcOE0fU/3G4BWKz6JFzFl+XjuxpIDc1VWL1XxL0X8ZKscc4kuBPi8IznpKwD cEkMzMjWBzlD00+KSi2O+Onh2IoD0RnuNPDKSVoxnBRrkQMKTRPM X-Developer-Key: i=quic_bjorande@quicinc.com; a=ed25519; pk=VkhObtljigy9k0ZUIE1Mvr0Y+E1dgBEH9WoLQnUtbIM= X-Originating-IP: [10.49.16.6] X-ClientProxiedBy: nalasex01c.na.qualcomm.com (10.47.97.35) To nalasex01c.na.qualcomm.com (10.47.97.35) X-QCInternal: smtphost X-Proofpoint-Virus-Version: vendor=nai engine=6200 definitions=5800 signatures=585085 X-Proofpoint-GUID: T7fwUtA8joYQe3ViHH0tIqzSM7z1ZP9M X-Proofpoint-ORIG-GUID: T7fwUtA8joYQe3ViHH0tIqzSM7z1ZP9M X-Proofpoint-Virus-Version: vendor=baseguard engine=ICAP:2.0.267,Aquarius:18.0.980,Hydra:6.0.601,FMLib:17.11.176.26 definitions=2023-09-20_14,2023-09-20_01,2023-05-22_02 X-Proofpoint-Spam-Details: rule=outbound_notspam policy=outbound score=0 malwarescore=0 clxscore=1011 phishscore=0 mlxlogscore=999 impostorscore=0 suspectscore=0 priorityscore=1501 mlxscore=0 spamscore=0 adultscore=0 lowpriorityscore=0 bulkscore=0 classifier=spam adjust=0 reason=mlx scancount=1 engine=8.12.0-2308100000 definitions=main-2309210021 Precedence: bulk List-ID: X-Mailing-List: linux-arm-msm@vger.kernel.org In some configurations, the exact placement of the rmtfs shared memory region isn't so strict. The DeviceTree author can then choose to use the "size" property and rely on the OS for placement (in combination with "alloc-ranges", if desired). But on some platforms the rmtfs memory region may not be allocated adjacent to regions allocated by other clients. Add support for discarding the first and last 4k block in the region, if qcom,use-guard-pages is specified in DeviceTree. Signed-off-by: Bjorn Andersson Reviewed-by: Stephan Gerhold --- drivers/soc/qcom/rmtfs_mem.c | 9 +++++++++ 1 file changed, 9 insertions(+) diff --git a/drivers/soc/qcom/rmtfs_mem.c b/drivers/soc/qcom/rmtfs_mem.c index f83811f51175..83bba9321e72 100644 --- a/drivers/soc/qcom/rmtfs_mem.c +++ b/drivers/soc/qcom/rmtfs_mem.c @@ -200,6 +200,15 @@ static int qcom_rmtfs_mem_probe(struct platform_device *pdev) rmtfs_mem->client_id = client_id; rmtfs_mem->size = rmem->size; + /* + * If requested, discard the first and last 4k block in order to ensure + * that the rmtfs region isn't adjacent to other protected regions. + */ + if (of_property_present(node, "qcom,use-guard-pages")) { + rmtfs_mem->addr += SZ_4K; + rmtfs_mem->size -= 2 * SZ_4K; + } + device_initialize(&rmtfs_mem->dev); rmtfs_mem->dev.parent = &pdev->dev; rmtfs_mem->dev.groups = qcom_rmtfs_mem_groups; From patchwork Thu Sep 21 02:37:32 2023 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Bjorn Andersson X-Patchwork-Id: 13393602 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 vger.kernel.org (vger.kernel.org [23.128.96.18]) by smtp.lore.kernel.org (Postfix) with ESMTP id 88310CD4938 for ; 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Wed, 20 Sep 2023 19:37:44 -0700 From: Bjorn Andersson Date: Wed, 20 Sep 2023 19:37:32 -0700 Subject: [PATCH v3 3/3] soc: qcom: rtmfs: Handle reserved-memory allocation issues MIME-Version: 1.0 Message-ID: <20230920-rmtfs-mem-guard-pages-v3-3-305b37219b78@quicinc.com> References: <20230920-rmtfs-mem-guard-pages-v3-0-305b37219b78@quicinc.com> In-Reply-To: <20230920-rmtfs-mem-guard-pages-v3-0-305b37219b78@quicinc.com> To: Andy Gross , Bjorn Andersson , Konrad Dybcio , Rob Herring , Krzysztof Kozlowski , Conor Dooley CC: , , , Bjorn Andersson X-Mailer: b4 0.12.0 X-Developer-Signature: v=1; a=ed25519-sha256; t=1695263863; l=904; i=quic_bjorande@quicinc.com; s=20230915; h=from:subject:message-id; bh=7jXz3rP8GNqMZsIHoKFFl+IwJpRuFh8oza0b3my6eAs=; b=HKuicCpF2ZYWAOR1HrVl0YJXuad3HGWt7ibs2VpT9C5bBFQEyFdqqVtLO8Syh8KZAFV74UbMKEsR XyGqjYLPCu8RK2914hN+iMYZGeH7+mcvoAy4fs/i3axKoxxZAyF9 X-Developer-Key: i=quic_bjorande@quicinc.com; a=ed25519; pk=VkhObtljigy9k0ZUIE1Mvr0Y+E1dgBEH9WoLQnUtbIM= X-Originating-IP: [10.49.16.6] X-ClientProxiedBy: nalasex01c.na.qualcomm.com (10.47.97.35) To nalasex01c.na.qualcomm.com (10.47.97.35) X-QCInternal: smtphost X-Proofpoint-Virus-Version: vendor=nai engine=6200 definitions=5800 signatures=585085 X-Proofpoint-ORIG-GUID: -XxDpDD5KCEqZ4iGvMDNfxJd37mWn0Jj X-Proofpoint-GUID: -XxDpDD5KCEqZ4iGvMDNfxJd37mWn0Jj X-Proofpoint-Virus-Version: vendor=baseguard engine=ICAP:2.0.267,Aquarius:18.0.980,Hydra:6.0.601,FMLib:17.11.176.26 definitions=2023-09-20_14,2023-09-20_01,2023-05-22_02 X-Proofpoint-Spam-Details: rule=outbound_notspam policy=outbound score=0 clxscore=1015 mlxlogscore=737 spamscore=0 adultscore=0 mlxscore=0 phishscore=0 impostorscore=0 malwarescore=0 priorityscore=1501 bulkscore=0 suspectscore=0 lowpriorityscore=0 classifier=spam adjust=0 reason=mlx scancount=1 engine=8.12.0-2308100000 definitions=main-2309210021 Precedence: bulk List-ID: X-Mailing-List: linux-arm-msm@vger.kernel.org In the even that Linux failed to allocate the reserved memory range specified in the DeviceTree, the size of the reserved_mem will be 0, which results in a oops when memory remapping is attempted. Detect this and report that the memory region was not found instead. Signed-off-by: Bjorn Andersson Acked-by: Konrad Dybcio --- drivers/soc/qcom/rmtfs_mem.c | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-) diff --git a/drivers/soc/qcom/rmtfs_mem.c b/drivers/soc/qcom/rmtfs_mem.c index 83bba9321e72..13823abd85c2 100644 --- a/drivers/soc/qcom/rmtfs_mem.c +++ b/drivers/soc/qcom/rmtfs_mem.c @@ -180,7 +180,7 @@ static int qcom_rmtfs_mem_probe(struct platform_device *pdev) int ret, i; rmem = of_reserved_mem_lookup(node); - if (!rmem) { + if (!rmem || !rmem->size) { dev_err(&pdev->dev, "failed to acquire memory region\n"); return -EINVAL; }