From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from smtp.kernel.org (aws-us-west-2-korg-mail-1.web.codeaurora.org [10.30.226.201]) (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 D8336197543; Thu, 6 Jun 2024 14:12:50 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.client-ip=10.30.226.201 ARC-Seal:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1717683170; cv=none; b=mvsUIrmmjBeEiuSV46EBzCTMtCSJif7Xxr3NyiL/Q9JVBsqKd0KVedDjXCclCAHNL8fyiA4eCb/2di/Ad6COsHih6eNXhva+tB3Jy6SVPzHAcSJOd7Gj5g/KITXEePawQ5k7YURGI6ZrPDL5xsqquSjFQA7iP5yEWGbsYSURz3g= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1717683170; c=relaxed/simple; bh=IKQRgDESD/QLqPh0oYWembQPfyrNuQGr0tQwGYyFlXo=; h=From:To:Cc:Subject:Date:Message-ID:In-Reply-To:References: MIME-Version; b=uI7pcKv5EKTQ6Zwx7yWroX4IBTnPu1ySCFQCpfgRKCKTnlJo0domXSTLsspp/LYWy5azw5YZZWcZ59NsgDl9OKu7wgFW8gZ4/MK/zMiq17+DZECG5eda6VS9s7ZCyEuYRsxEIBgSV323u4Prohm4+tt2+JXL6EGfCOcgKqOQFWs= ARC-Authentication-Results:i=1; smtp.subspace.kernel.org; dkim=pass (1024-bit key) header.d=linuxfoundation.org header.i=@linuxfoundation.org header.b=z9zGUOD8; arc=none smtp.client-ip=10.30.226.201 Authentication-Results: smtp.subspace.kernel.org; dkim=pass (1024-bit key) header.d=linuxfoundation.org header.i=@linuxfoundation.org header.b="z9zGUOD8" Received: by smtp.kernel.org (Postfix) with ESMTPSA id 611F6C32782; Thu, 6 Jun 2024 14:12:50 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=linuxfoundation.org; s=korg; t=1717683170; bh=IKQRgDESD/QLqPh0oYWembQPfyrNuQGr0tQwGYyFlXo=; h=From:To:Cc:Subject:Date:In-Reply-To:References:From; b=z9zGUOD83CYilq/fHqAHEnik9AfhL9tV1S3naaxA0SNZvhYcBDxPZVgOZlrF77vs9 tKMH6VkXrUFXj1N35gacXqNhNbkHEGSk3CRfHZRSPBVEi5jPf1P+txhu98xeQFgTlI IeIeLA8JXamaBot52kl9NL1ek7gcjI4/58BvGFRo= From: Greg Kroah-Hartman To: stable@vger.kernel.org Cc: Greg Kroah-Hartman , patches@lists.linux.dev, Mukesh Ojha , Bjorn Andersson , Sasha Levin Subject: [PATCH 6.6 115/744] firmware: qcom: scm: Fix __scm and waitq completion variable initialization Date: Thu, 6 Jun 2024 15:56:27 +0200 Message-ID: <20240606131736.088312649@linuxfoundation.org> X-Mailer: git-send-email 2.45.2 In-Reply-To: <20240606131732.440653204@linuxfoundation.org> References: <20240606131732.440653204@linuxfoundation.org> User-Agent: quilt/0.67 X-stable: review X-Patchwork-Hint: ignore Precedence: bulk X-Mailing-List: patches@lists.linux.dev List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 Content-Transfer-Encoding: 8bit 6.6-stable review patch. If anyone has any objections, please let me know. ------------------ From: Mukesh Ojha [ Upstream commit 2e4955167ec5c04534cebea9e8273a907e7a75e1 ] It is possible qcom_scm_is_available() gives wrong indication that if __scm is initialized while __scm->dev is not and similar issue is also possible with __scm->waitq_comp. Fix this appropriately by the use of release barrier and read barrier that will make sure if __scm is initialized so, is all of its field variable. Fixes: d0f6fa7ba2d6 ("firmware: qcom: scm: Convert SCM to platform driver") Fixes: 6bf325992236 ("firmware: qcom: scm: Add wait-queue handling logic") Signed-off-by: Mukesh Ojha Link: https://lore.kernel.org/r/1711034642-22860-4-git-send-email-quic_mojha@quicinc.com Signed-off-by: Bjorn Andersson Signed-off-by: Sasha Levin --- drivers/firmware/qcom_scm.c | 10 +++++----- 1 file changed, 5 insertions(+), 5 deletions(-) diff --git a/drivers/firmware/qcom_scm.c b/drivers/firmware/qcom_scm.c index 69831f1d91e3f..ff7c155239e31 100644 --- a/drivers/firmware/qcom_scm.c +++ b/drivers/firmware/qcom_scm.c @@ -1333,7 +1333,7 @@ static int qcom_scm_find_dload_address(struct device *dev, u64 *addr) */ bool qcom_scm_is_available(void) { - return !!__scm; + return !!READ_ONCE(__scm); } EXPORT_SYMBOL_GPL(qcom_scm_is_available); @@ -1414,10 +1414,12 @@ static int qcom_scm_probe(struct platform_device *pdev) if (!scm) return -ENOMEM; + scm->dev = &pdev->dev; ret = qcom_scm_find_dload_address(&pdev->dev, &scm->dload_mode_addr); if (ret < 0) return ret; + init_completion(&scm->waitq_comp); mutex_init(&scm->scm_bw_lock); scm->path = devm_of_icc_get(&pdev->dev, NULL); @@ -1449,10 +1451,8 @@ static int qcom_scm_probe(struct platform_device *pdev) if (ret) return ret; - __scm = scm; - __scm->dev = &pdev->dev; - - init_completion(&__scm->waitq_comp); + /* Let all above stores be available after this */ + smp_store_release(&__scm, scm); irq = platform_get_irq_optional(pdev, 0); if (irq < 0) { -- 2.43.0