From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from smtp.kernel.org (aws-us-west-2-korg-mail-alma10-1.taild15c8.ts.net [100.103.45.18]) (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 9B1B430566A; Wed, 30 Sep 2026 18:59:36 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.client-ip=100.103.45.18 ARC-Seal:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1790794777; cv=none; b=tgxwq/hdL75BJDLOnS+ElSU9qMWVEUwZs1AJC2eyE0+1ySVeTmbAkrqY/5HtdIaQaKdPBd8FAqXsj+c02WWU3W9HxlfpwDFvpXZDWIVl0smSRYKUmTEcsfi9wYHcIqipzg5WQ9F1lI4TjLEDtETI9FnTxebhCjNVoscEpWwuwdM= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1790794777; c=relaxed/simple; bh=Ar5XDrAqRBS+YSYBiyPydn2z/FnXVI6FPBIC0Krbjb4=; h=From:To:Cc:Subject:Date:Message-ID:In-Reply-To:References: MIME-Version:Content-Type; b=Dy/9cqDs6pSZNF/UfG+3yWMGkkUN/0/SlnEhX4Xp7d1F+SWoeYqBkHL12Okdsuqe15onzOtTUrrIZXw+eOyi81FkFdQA2VqZR244af5MNtvT8Z2VAho3OrNGxRyU1d/cD4iEvgaLbyygtQSV8QmUn5XHXX4iORkXtkPtr+rqPIg= ARC-Authentication-Results:i=1; smtp.subspace.kernel.org; dkim=pass (1024-bit key) header.d=linuxfoundation.org header.i=@linuxfoundation.org header.b=j4/T4IBe; arc=none smtp.client-ip=100.103.45.18 Authentication-Results: smtp.subspace.kernel.org; dkim=pass (1024-bit key) header.d=linuxfoundation.org header.i=@linuxfoundation.org header.b="j4/T4IBe" Received: by smtp.kernel.org (Postfix) with ESMTPSA id 015271F000FF; Wed, 30 Sep 2026 18:59:35 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=linuxfoundation.org; s=korg; t=1790794776; bh=Mj+NBBycxkApM9X9XT0Y6XNMh2itvu3uWYkT6ycgAFM=; h=From:To:Cc:Subject:Date:In-Reply-To:References; b=j4/T4IBejTl8lDxnzd2999ysZUx0kk30Dh1qomt7u0/+VdnzGq6t6UdDiiZzKENHe TLb86G47CD53OPq6Eo7B4bQw6C+cFYc8EhbqYL1c8e0WobG5aA484ONDxyEktO5y6r La2xCHGRbt3JQHSOkWrSSUHgq3UXuv0XpsgDPKro= From: Greg Kroah-Hartman To: stable@vger.kernel.org Cc: Greg Kroah-Hartman , patches@lists.linux.dev, =?UTF-8?q?Gustavo=20Kenji=20Mendon=C3=A7a=20Kaneko?= , Liviu Dudau , Sasha Levin Subject: [PATCH 6.6 0275/1193] drm/arm/komeda: fix error handling for clk_prepare_enable() and callers Date: Wed, 30 Sep 2026 17:15:59 +0200 Message-ID: <20260930152440.273879227@linuxfoundation.org> X-Mailer: git-send-email 2.55.0 In-Reply-To: <20260930152434.301151190@linuxfoundation.org> References: <20260930152434.301151190@linuxfoundation.org> User-Agent: quilt/0.69 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-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 8bit 6.6-stable review patch. If anyone has any objections, please let me know. ------------------ From: Gustavo Kenji Mendonça Kaneko [ Upstream commit 6502eb8cfcd6f7bc5f1f8b73ee524112bd93319d ] komeda_dev_resume() calls clk_prepare_enable() without checking the return value. If the clock fails to enable, the function returns 0 (success) while IRQs are enabled and IOMMU is connected on potentially unclocked hardware, causing undefined behavior on resume. Propagate the error from clk_prepare_enable() and fix all call sites in komeda_drv.c that previously ignored the return value of komeda_dev_resume(): - komeda_platform_probe(): if resume fails, jump to err_destroy_mdev (skipping the suspend call, since the clock was never enabled) - komeda_pm_resume(): propagate the error and skip drm_mode_config_helper_resume() on failure This issue was found by code review without access to Komeda hardware. Signed-off-by: Gustavo Kenji Mendonça Kaneko Reviewed-by: Liviu Dudau Link: https://patch.msgid.link/20260609130828.1066038-1-kaneko.dev@pm.me Signed-off-by: Liviu Dudau Signed-off-by: Sasha Levin --- drivers/gpu/drm/arm/display/komeda/komeda_dev.c | 6 +++++- drivers/gpu/drm/arm/display/komeda/komeda_drv.c | 14 +++++++++----- 2 files changed, 14 insertions(+), 6 deletions(-) diff --git a/drivers/gpu/drm/arm/display/komeda/komeda_dev.c b/drivers/gpu/drm/arm/display/komeda/komeda_dev.c index 14ee79becacb5..73dc628d72700 100644 --- a/drivers/gpu/drm/arm/display/komeda/komeda_dev.c +++ b/drivers/gpu/drm/arm/display/komeda/komeda_dev.c @@ -321,7 +321,11 @@ void komeda_dev_destroy(struct komeda_dev *mdev) int komeda_dev_resume(struct komeda_dev *mdev) { - clk_prepare_enable(mdev->aclk); + int err; + + err = clk_prepare_enable(mdev->aclk); + if (err) + return err; mdev->funcs->enable_irq(mdev); diff --git a/drivers/gpu/drm/arm/display/komeda/komeda_drv.c b/drivers/gpu/drm/arm/display/komeda/komeda_drv.c index cb2a2be24c5ff..abcaf76ae599e 100644 --- a/drivers/gpu/drm/arm/display/komeda/komeda_drv.c +++ b/drivers/gpu/drm/arm/display/komeda/komeda_drv.c @@ -62,8 +62,11 @@ static int komeda_platform_probe(struct platform_device *pdev) } pm_runtime_enable(dev); - if (!pm_runtime_enabled(dev)) - komeda_dev_resume(mdrv->mdev); + if (!pm_runtime_enabled(dev)) { + err = komeda_dev_resume(mdrv->mdev); + if (err) + goto err_destroy_mdev; + } mdrv->kms = komeda_kms_attach(mdrv->mdev); if (IS_ERR(mdrv->kms)) { @@ -81,7 +84,7 @@ static int komeda_platform_probe(struct platform_device *pdev) pm_runtime_disable(dev); else komeda_dev_suspend(mdrv->mdev); - +err_destroy_mdev: komeda_dev_destroy(mdrv->mdev); free_mdrv: @@ -127,11 +130,12 @@ static int __maybe_unused komeda_pm_suspend(struct device *dev) static int __maybe_unused komeda_pm_resume(struct device *dev) { struct komeda_drv *mdrv = dev_get_drvdata(dev); + int err = 0; if (!pm_runtime_status_suspended(dev)) - komeda_dev_resume(mdrv->mdev); + err = komeda_dev_resume(mdrv->mdev); - return drm_mode_config_helper_resume(&mdrv->kms->base); + return err ? err : drm_mode_config_helper_resume(&mdrv->kms->base); } static const struct dev_pm_ops komeda_pm_ops = { -- 2.53.0