From mboxrd@z Thu Jan 1 00:00:00 1970 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 9489AC7EE22 for ; Thu, 4 May 2023 16:34:52 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S229848AbjEDQev (ORCPT ); Thu, 4 May 2023 12:34:51 -0400 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:53288 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S229927AbjEDQeq (ORCPT ); Thu, 4 May 2023 12:34:46 -0400 Received: from mail-ej1-x633.google.com (mail-ej1-x633.google.com [IPv6:2a00:1450:4864:20::633]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id EDE1E3C0C for ; Thu, 4 May 2023 09:34:36 -0700 (PDT) Received: by mail-ej1-x633.google.com with SMTP id a640c23a62f3a-956eacbe651so138866466b.3 for ; Thu, 04 May 2023 09:34:36 -0700 (PDT) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=linaro.org; s=google; t=1683218075; x=1685810075; h=content-transfer-encoding:in-reply-to:references:cc:to:from :content-language:subject:user-agent:mime-version:date:message-id :from:to:cc:subject:date:message-id:reply-to; bh=nszTvAg6fphYuzaPSYnd3w5WMHZrZJJaEUI5zTnvsx4=; b=dhxD37R48wLSmMqoo+yOvb619nXn47MDnAlUoME6jFo/UJ4C+dA44spBJdEsQXo/BB ZJATJlWpYr1F5QCJ6s4RbliW9MHK/oFSkY0nYFR4f0yiNMmYfywayOEQedzYAybRAfgf l926ylMz4mrzTXBojvCkJGyiiK4Nt/Z5vnxxDPKwxpzhN8BnWyhI/3Z3fqL0sARvjGL3 nEqAjz6mwz7o5kO33wL8e4wrte01H86lLz7FmFbBcYDnJfOE+HEmf+MVoK+XrfQByDpC YLwdqYNtyB4F+0X8T4psmNmW2EkRXtWJoHu47vmhJk6a1mzVnGPmJcViYA00Qi45MKpn NCJQ== X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20221208; t=1683218075; x=1685810075; h=content-transfer-encoding:in-reply-to:references:cc:to:from :content-language:subject:user-agent:mime-version:date:message-id :x-gm-message-state:from:to:cc:subject:date:message-id:reply-to; bh=nszTvAg6fphYuzaPSYnd3w5WMHZrZJJaEUI5zTnvsx4=; b=l9LsgHgcOVB5Hq+BnHlFyNKTARk6z/qyRaWrdHkZAJGuujVAUt956t+mkNlQBL30Xk h2wyZ/YsOtH71HZ7fMRYxDtV++rJ8qzT3VDeTTg1TOLD/WwzThdcaHuobsYgrq2Bg+O9 E/E8ZxsiPlUdRIFig9SuWysQbO5OJ+81keh+Ghfg5JDlGYoS78k+KKOORXQgo7zaqQ83 r3oM7cpWrWbEGT7pKr6jCt5sjAJBWP/JfT/msPjD/Zk8yp0ALKtcBsDVbkJYElTcyNmh Q2qfTfHY+bG4jpMCdAUtoOhx+tNFae+qSPC4SLnKOVaWgpRd0AhsZYejN9wPhUjM1UEb 8dZw== X-Gm-Message-State: AC+VfDxF4k4frXIA55idPF+rTed60qMzx9E4753RHrtiKo3S7Dbj3ovJ MD6wUnuGtehM4VBvVGIZPVJ5CQ== X-Google-Smtp-Source: ACHHUZ7UTw09BUZkzS6zw6s3B83bTJ2iIzEWu8O3/gcd5QbYIqL3Pcttt0DLEfeqNgf6m6beVNV0ow== X-Received: by 2002:a17:907:a412:b0:961:be96:b0e0 with SMTP id sg18-20020a170907a41200b00961be96b0e0mr6847612ejc.73.1683218075231; Thu, 04 May 2023 09:34:35 -0700 (PDT) Received: from ?IPV6:2a02:810d:15c0:828:bdb9:99c4:33a5:6114? ([2a02:810d:15c0:828:bdb9:99c4:33a5:6114]) by smtp.gmail.com with ESMTPSA id n20-20020a1709065db400b00965b439027csm802967ejv.195.2023.05.04.09.34.33 (version=TLS1_3 cipher=TLS_AES_128_GCM_SHA256 bits=128/128); Thu, 04 May 2023 09:34:34 -0700 (PDT) Message-ID: <500e5abc-fb71-8468-a6b0-3ced2676b57c@linaro.org> Date: Thu, 4 May 2023 18:34:32 +0200 MIME-Version: 1.0 User-Agent: Mozilla/5.0 (X11; Linux x86_64; rv:102.0) Gecko/20100101 Thunderbird/102.10.1 Subject: Re: [PATCH v3 04/18] soc: qcom: Add Qualcomm minidump kernel driver Content-Language: en-US From: Krzysztof Kozlowski To: Mukesh Ojha , agross@kernel.org, andersson@kernel.org, konrad.dybcio@linaro.org, corbet@lwn.net, keescook@chromium.org, tony.luck@intel.com, gpiccoli@igalia.com, catalin.marinas@arm.com, will@kernel.org, krzysztof.kozlowski+dt@linaro.org, robh+dt@kernel.org, linus.walleij@linaro.org, linux-gpio@vger.kernel.org, srinivas.kandagatla@linaro.org Cc: linux-arm-msm@vger.kernel.org, linux-remoteproc@vger.kernel.org, linux-kernel@vger.kernel.org, linux-hardening@vger.kernel.org, linux-arm-kernel@lists.infradead.org, linux-doc@vger.kernel.org References: <1683133352-10046-1-git-send-email-quic_mojha@quicinc.com> <1683133352-10046-5-git-send-email-quic_mojha@quicinc.com> <23b493f4-1a01-8d03-fc12-d588b2c6fd74@quicinc.com> <575a422d-6224-06b7-628c-8487b47882e9@linaro.org> In-Reply-To: <575a422d-6224-06b7-628c-8487b47882e9@linaro.org> Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 7bit Precedence: bulk List-ID: X-Mailing-List: linux-doc@vger.kernel.org On 04/05/2023 17:21, Krzysztof Kozlowski wrote: >>> >>>> + ret = qcom_minidump_init_apss_subsystem(md); >>>> + if (ret) { >>>> + dev_err(&pdev->dev, "apss minidump initialization failed: %d\n", ret); >>>> + goto unlock; >>>> + } >>>> + >>>> + __md = md; >>> >>> No. This is a platform device, so it can have multiple instances. >> >> It can have only one instance that is created from SMEM driver probe. > > Anyone can instantiate more of them.... how did you solve it? To clarify - sprinkling more of singletons makes everything tightly coupled, difficult to debug and non-portable. You cannot have two instances, you have to control concurrent initialization by yourself in each of such singletons. I understand sometimes they are unavoidable, for example when this does not map to hardware property. However here you have the parent - smem - which can return you valid instance. Thus you avoid entire problem of file-scope variables. Best regards, Krzysztof