From patchwork Fri Nov 24 22:19:53 2023 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Mukesh Ojha X-Patchwork-Id: 13468196 Authentication-Results: smtp.subspace.kernel.org; dkim=pass (2048-bit key) header.d=quicinc.com header.i=@quicinc.com header.b="dVNS6Jyg" Received: from mx0a-0031df01.pphosted.com (mx0a-0031df01.pphosted.com [205.220.168.131]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id 6F8C91BC7; Fri, 24 Nov 2023 14:22:00 -0800 (PST) Received: from pps.filterd (m0279864.ppops.net [127.0.0.1]) by mx0a-0031df01.pphosted.com (8.17.1.19/8.17.1.19) with ESMTP id 3AOLVLxI017056; Fri, 24 Nov 2023 22:21:41 GMT DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=quicinc.com; h=from : to : cc : subject : date : message-id : in-reply-to : references : mime-version : content-type; s=qcppdkim1; bh=dzhYh7LrMvBp4kXy7q9UTgYwttlEksL+Qn973TCYLxA=; b=dVNS6Jyg3rH/RfJP2BDZnTTiCmcn6gBFHW0eCb3RMm7kMiDQJHtQtQ2rRA/ja9KS5A0m 8jpN2sVvj/J/X8CT2U1baYv12wIVqrhEZtGafQrRRRe+2XdZrjKSoQOplrK36thlieiG 6v7tMjHHXTPnKaaVMaDW1iyvf52EDdVIMvXWbGNW2EQOtzGoBoT7rjFaaQg/I9/og2/D 68nGddAWL/OB2++snRzfSSHLR9SW0whg6W5YxhH2/iiIQBM3ojjp3xwdw3kuslXk8OG0 D9QgUbWzIveN+vXMaCW1MpXMJJgyDYyXwf3ZVI8QKLtMEcw89qfEuAIsEoceqDAEUWSm Gg== Received: from nasanppmta02.qualcomm.com (i-global254.qualcomm.com [199.106.103.254]) by mx0a-0031df01.pphosted.com (PPS) with ESMTPS id 3ujhh4tjd4-1 (version=TLSv1.2 cipher=ECDHE-RSA-AES256-GCM-SHA384 bits=256 verify=NOT); Fri, 24 Nov 2023 22:21:40 +0000 Received: from nasanex01c.na.qualcomm.com (nasanex01c.na.qualcomm.com [10.45.79.139]) by NASANPPMTA02.qualcomm.com (8.17.1.5/8.17.1.5) with ESMTPS id 3AOMLdts018614 (version=TLSv1.2 cipher=ECDHE-RSA-AES256-GCM-SHA384 bits=256 verify=NOT); Fri, 24 Nov 2023 22:21:39 GMT Received: from hu-mojha-hyd.qualcomm.com (10.80.80.8) by nasanex01c.na.qualcomm.com (10.45.79.139) with Microsoft SMTP Server (version=TLS1_2, cipher=TLS_ECDHE_RSA_WITH_AES_256_GCM_SHA384) id 15.2.1118.40; Fri, 24 Nov 2023 14:21:30 -0800 From: Mukesh Ojha To: , , , , , , , , , , , , , , , , CC: , , , , , , , , , Mukesh Ojha Subject: [Patch v6 10/12] pstore/ram: Add dynamic ramoops region support through commandline Date: Sat, 25 Nov 2023 03:49:53 +0530 Message-ID: <1700864395-1479-11-git-send-email-quic_mojha@quicinc.com> X-Mailer: git-send-email 2.7.4 In-Reply-To: <1700864395-1479-1-git-send-email-quic_mojha@quicinc.com> References: <1700864395-1479-1-git-send-email-quic_mojha@quicinc.com> Precedence: bulk X-Mailing-List: linux-hardening@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 X-ClientProxiedBy: nasanex01b.na.qualcomm.com (10.46.141.250) To nasanex01c.na.qualcomm.com (10.45.79.139) X-QCInternal: smtphost X-Proofpoint-Virus-Version: vendor=nai engine=6200 definitions=5800 signatures=585085 X-Proofpoint-GUID: YnvGFjnTQMFwQ9tSAtnR_3ymn6TUt3_b X-Proofpoint-ORIG-GUID: YnvGFjnTQMFwQ9tSAtnR_3ymn6TUt3_b X-Proofpoint-Virus-Version: vendor=baseguard engine=ICAP:2.0.272,Aquarius:18.0.987,Hydra:6.0.619,FMLib:17.11.176.26 definitions=2023-11-24_09,2023-11-22_01,2023-05-22_02 X-Proofpoint-Spam-Details: rule=outbound_notspam policy=outbound score=0 suspectscore=0 mlxlogscore=999 priorityscore=1501 adultscore=0 lowpriorityscore=0 malwarescore=0 mlxscore=0 clxscore=1015 phishscore=0 bulkscore=0 impostorscore=0 spamscore=0 classifier=spam adjust=0 reason=mlx scancount=1 engine=8.12.0-2311060000 definitions=main-2311240174 The reserved memory region for ramoops is assumed to be at a fixed and known location when read from the devicetree. This may not be required for something like Qualcomm's minidump which is interested in knowing addresses of ramoops region but it does not put hard requirement of address being fixed as most of it's SoC does not support warm reset and does not use pstorefs at all instead it has firmware way of collecting ramoops region if it gets to know the address and register it with apss minidump table which is sitting in shared memory region in DDR and firmware will have access to these table during reset and collects it on crash of SoC. So, add the support of reserving ramoops region to be dynamically allocated early during boot if it is request through command line via 'dyn_ramoops_size=' and fill up reserved resource structure and export the structure, so that it can be read by ramoops driver. Signed-off-by: Mukesh Ojha --- Documentation/admin-guide/ramoops.rst | 7 ++++ fs/pstore/Kconfig | 15 +++++++++ fs/pstore/ram.c | 62 ++++++++++++++++++++++++++++++++--- include/linux/pstore_ram.h | 5 +++ init/main.c | 2 ++ 5 files changed, 87 insertions(+), 4 deletions(-) diff --git a/Documentation/admin-guide/ramoops.rst b/Documentation/admin-guide/ramoops.rst index e9f85142182d..af737adbf079 100644 --- a/Documentation/admin-guide/ramoops.rst +++ b/Documentation/admin-guide/ramoops.rst @@ -33,6 +33,13 @@ memory are implementation defined, and won't work on many ARMs such as omaps. Setting ``mem_type=2`` attempts to treat the memory region as normal memory, which enables full cache on it. This can improve the performance. +Ramoops memory region can also be allocated dynamically for a special case where +there is no requirement to access the logs from pstorefs on next boot instead there +is separate backend mechanism like minidump present which has awareness about the +dynamic ramoops region and can recover the logs. This is enabled via command line +parameter ``dyn_ramoops_size=`` and should not be used in absence of +separate backend which knows how to recover this dynamic region. + The memory area is divided into ``record_size`` chunks (also rounded down to power of two) and each kmesg dump writes a ``record_size`` chunk of information. diff --git a/fs/pstore/Kconfig b/fs/pstore/Kconfig index 3acc38600cd1..e13e53d7a225 100644 --- a/fs/pstore/Kconfig +++ b/fs/pstore/Kconfig @@ -81,6 +81,21 @@ config PSTORE_RAM For more information, see Documentation/admin-guide/ramoops.rst. +config PSTORE_DYNAMIC_RAMOOPS_REGION_RESERVATION + bool "Reserve ramoops region dynamically" + select PSTORE_RAM + help + This enables the dynamic reservation of ramoops region for a special case + where there is no requirement to access the logs from pstorefs on next boot + instead there is separate backend mechanism like minidump present which has + awareness about the dynamic ramoops region and can recover the logs. This is + enabled via command line parameter dyn_ramoops_size= and should not be + used in absence of separate backend which knows how to recover this dynamic + region. + + Note whenever this config is selected ramoops driver will be build statically + into kernel. + config PSTORE_ZONE tristate depends on PSTORE diff --git a/fs/pstore/ram.c b/fs/pstore/ram.c index 88b34fdbf759..a6c0da8cfdd4 100644 --- a/fs/pstore/ram.c +++ b/fs/pstore/ram.c @@ -20,6 +20,7 @@ #include #include #include +#include #include #include "internal.h" @@ -103,6 +104,55 @@ struct ramoops_context { }; static struct platform_device *dummy; +static int dyn_ramoops_size; +/* Location of the reserved area for the dynamic ramoops */ +static struct resource dyn_ramoops_res = { + .name = "ramoops", + .start = 0, + .end = 0, + .flags = IORESOURCE_BUSY | IORESOURCE_SYSTEM_RAM, + .desc = IORES_DESC_NONE, +}; + +static int __init parse_dyn_ramoops_size(char *p) +{ + char *tmp; + + dyn_ramoops_size = memparse(p, &tmp); + if (p == tmp) { + pr_err("ramoops: memory size expected\n"); + return -EINVAL; + } + + return 0; +} +early_param("dyn_ramoops_size", parse_dyn_ramoops_size); + +#ifdef CONFIG_PSTORE_DYNAMIC_RAMOOPS_REGION_RESERVATION +/* + * setup_dynamic_ramoops() - reserves memory for dynamic ramoops + * + * This enable dynamic reserve memory support for ramoops through + * command line. + */ +void __init setup_dynamic_ramoops(void) +{ + unsigned long long ramoops_base; + unsigned long long ramoops_size; + + ramoops_base = memblock_phys_alloc_range(dyn_ramoops_size, SMP_CACHE_BYTES, + 0, MEMBLOCK_ALLOC_NOLEAKTRACE); + if (!ramoops_base) { + pr_err("cannot allocate ramoops dynamic memory (size:0x%llx).\n", + ramoops_size); + return; + } + + dyn_ramoops_res.start = ramoops_base; + dyn_ramoops_res.end = ramoops_base + dyn_ramoops_size - 1; + insert_resource(&iomem_resource, &dyn_ramoops_res); +} +#endif static int ramoops_pstore_open(struct pstore_info *psi) { @@ -915,14 +965,18 @@ static void __init ramoops_register_dummy(void) /* * Prepare a dummy platform data structure to carry the module - * parameters. If mem_size isn't set, then there are no module - * parameters, and we can skip this. + * parameters. If mem_size isn't set, check for dynamic ramoops + * size and use if it is set. */ - if (!mem_size) + if (!mem_size && !dyn_ramoops_size) return; - pr_info("using module parameters\n"); + if (dyn_ramoops_size) { + mem_size = dyn_ramoops_size; + mem_address = dyn_ramoops_res.start; + } + pr_info("using module parameters\n"); memset(&pdata, 0, sizeof(pdata)); pdata.mem_size = mem_size; pdata.mem_address = mem_address; diff --git a/include/linux/pstore_ram.h b/include/linux/pstore_ram.h index 9d65ff94e216..b3537336c4e1 100644 --- a/include/linux/pstore_ram.h +++ b/include/linux/pstore_ram.h @@ -39,4 +39,9 @@ struct ramoops_platform_data { struct persistent_ram_ecc_info ecc_info; }; +#ifdef CONFIG_PSTORE_DYNAMIC_RAMOOPS_REGION_RESERVATION +void __init setup_dynamic_ramoops(void); +#else +static inline void __init setup_dynamic_ramoops(void) {} +#endif #endif diff --git a/init/main.c b/init/main.c index e24b0780fdff..32c7d94558ec 100644 --- a/init/main.c +++ b/init/main.c @@ -99,6 +99,7 @@ #include #include #include +#include #include #include @@ -895,6 +896,7 @@ void start_kernel(void) pr_notice("%s", linux_banner); early_security_init(); setup_arch(&command_line); + setup_dynamic_ramoops(); setup_boot_config(); setup_command_line(command_line); setup_nr_cpu_ids();