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 86DA9C072A2 for ; Wed, 15 Nov 2023 19:48:44 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S235327AbjKOTso (ORCPT ); Wed, 15 Nov 2023 14:48:44 -0500 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:50074 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S235320AbjKOTsn (ORCPT ); Wed, 15 Nov 2023 14:48:43 -0500 Received: from smtp.kernel.org (relay.kernel.org [52.25.139.140]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id E33B2B9 for ; Wed, 15 Nov 2023 11:48:39 -0800 (PST) Received: by smtp.kernel.org (Postfix) with ESMTPSA id 593CCC433C7; Wed, 15 Nov 2023 19:48:39 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=linuxfoundation.org; s=korg; t=1700077719; bh=2yu1O77oVX65xeyt0HNIuhcxJruVQOqElDSj7tozYbE=; h=From:To:Cc:Subject:Date:In-Reply-To:References:From; b=AM6LTbWdDNsumEkemAznkJUIbosiVOjiCloOXfET9lskEG4xd4TUEsqc9mdjx7WCV VEm/JTyiuROOJVujFSlSsVWaGDr3/Bxkehvk9E7AflH4dvRdTlYOUI7btaSR9vq9xM /U/u30OH3T5nI35w8V20gmJUDWuMgBB3Q/K7MxNY= From: Greg Kroah-Hartman To: stable@vger.kernel.org Cc: Greg Kroah-Hartman , patches@lists.linux.dev, Sergey Shtylyov , Mathias Nyman , Sasha Levin Subject: [PATCH 6.6 477/603] usb: host: xhci-plat: fix possible kernel oops while resuming Date: Wed, 15 Nov 2023 14:17:02 -0500 Message-ID: <20231115191645.451285413@linuxfoundation.org> X-Mailer: git-send-email 2.42.1 In-Reply-To: <20231115191613.097702445@linuxfoundation.org> References: <20231115191613.097702445@linuxfoundation.org> User-Agent: quilt/0.67 X-stable: review X-Patchwork-Hint: ignore MIME-Version: 1.0 Content-Transfer-Encoding: 8bit Precedence: bulk List-ID: X-Mailing-List: stable@vger.kernel.org 6.6-stable review patch. If anyone has any objections, please let me know. ------------------ From: Sergey Shtylyov [ Upstream commit a5f928db59519a15e82ecba4ae3e7cbf5a44715a ] If this driver enables the xHC clocks while resuming from sleep, it calls clk_prepare_enable() without checking for errors and blithely goes on to read/write the xHC's registers -- which, with the xHC not being clocked, at least on ARM32 usually causes an imprecise external abort exceptions which cause kernel oops. Currently, the chips for which the driver does the clock dance on suspend/resume seem to be the Broadcom STB SoCs, based on ARM32 CPUs, as it seems... Found by Linux Verification Center (linuxtesting.org) with the Svace static analysis tool. Fixes: 8bd954c56197 ("usb: host: xhci-plat: suspend and resume clocks") Signed-off-by: Sergey Shtylyov Signed-off-by: Mathias Nyman Link: https://lore.kernel.org/r/20231019102924.2797346-19-mathias.nyman@linux.intel.com Signed-off-by: Greg Kroah-Hartman Signed-off-by: Sasha Levin --- drivers/usb/host/xhci-plat.c | 23 +++++++++++++++++++---- 1 file changed, 19 insertions(+), 4 deletions(-) diff --git a/drivers/usb/host/xhci-plat.c b/drivers/usb/host/xhci-plat.c index 28218c8f18376..b93161374293b 100644 --- a/drivers/usb/host/xhci-plat.c +++ b/drivers/usb/host/xhci-plat.c @@ -458,23 +458,38 @@ static int __maybe_unused xhci_plat_resume(struct device *dev) int ret; if (!device_may_wakeup(dev) && (xhci->quirks & XHCI_SUSPEND_RESUME_CLKS)) { - clk_prepare_enable(xhci->clk); - clk_prepare_enable(xhci->reg_clk); + ret = clk_prepare_enable(xhci->clk); + if (ret) + return ret; + + ret = clk_prepare_enable(xhci->reg_clk); + if (ret) { + clk_disable_unprepare(xhci->clk); + return ret; + } } ret = xhci_priv_resume_quirk(hcd); if (ret) - return ret; + goto disable_clks; ret = xhci_resume(xhci, PMSG_RESUME); if (ret) - return ret; + goto disable_clks; pm_runtime_disable(dev); pm_runtime_set_active(dev); pm_runtime_enable(dev); return 0; + +disable_clks: + if (!device_may_wakeup(dev) && (xhci->quirks & XHCI_SUSPEND_RESUME_CLKS)) { + clk_disable_unprepare(xhci->clk); + clk_disable_unprepare(xhci->reg_clk); + } + + return ret; } static int __maybe_unused xhci_plat_runtime_suspend(struct device *dev) -- 2.42.0