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 7BEFF34A79D; Sat, 30 May 2026 16:31:35 +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=1780158696; cv=none; b=i7rdpvMMco7WWKGENAGcWtFnszg190Wd/v1Jk1pOk4YwBqld6sC1EcRX4Lr19d48N+4wrez2rCP2FDXAvLjNxwrtPQng5eMuG1U6tsksMW6+/3BgxkXDlw183IyVw03xoh2rEnpRvqC1/DhbEadK9TfJGqc0d9mh21vstSEPeP0= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1780158696; c=relaxed/simple; bh=H3LxCqnb+Y/jLpPKC3ZtJYhMMK2ylzqrAbO9R3L1Wwk=; h=From:To:Cc:Subject:Date:Message-ID:In-Reply-To:References: MIME-Version; b=k3CWRHb5t8KMpUgp08Fz8znigm0TShfQtbbBw8o9gMDIdM4ykZ3j961nWDoKyzwe/zSMjLMTDHRHIZQA/9OMhIbKtAiCVNuwfXCcOs3t3njZ/EKhmOtn01OpjJmbPs5EuFNNaSl8L9JujvZTYencVAfNJ1nZiHgBc5Gvbr7XnY4= ARC-Authentication-Results:i=1; smtp.subspace.kernel.org; dkim=pass (1024-bit key) header.d=linuxfoundation.org header.i=@linuxfoundation.org header.b=FxtrNpx8; 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="FxtrNpx8" Received: by smtp.kernel.org (Postfix) with ESMTPSA id 6FC441F00893; Sat, 30 May 2026 16:31:31 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=linuxfoundation.org; s=korg; t=1780158695; bh=A1yR4tkAVHYBDwdeZDcuHAvZM+6SMfkGS7jUI5kfiNg=; h=From:To:Cc:Subject:Date:In-Reply-To:References; b=FxtrNpx8kBL68i4xe35pK4aeOTSlmu4asw9x+2jZ8v6MHP21vPNjl5X+iySMNg+kM pMRT8U6QKFZZ5OCk8NVyQdXkVjEEICHaUtUXlc39Gr3itZ4u1qdqblNF+JzEzgJKJs L3C8L5iqWdKLldvCC3CYLSQM1sjXHhGdbVcAAXtY= From: Greg Kroah-Hartman To: stable@vger.kernel.org Cc: Greg Kroah-Hartman , patches@lists.linux.dev, stable@kernel.org, Xu Yang Subject: [PATCH 6.1 075/969] usb: port: add delay after usb_hub_set_port_power() Date: Sat, 30 May 2026 17:53:19 +0200 Message-ID: <20260530160302.426546834@linuxfoundation.org> X-Mailer: git-send-email 2.53.0 In-Reply-To: <20260530160300.485627683@linuxfoundation.org> References: <20260530160300.485627683@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-Transfer-Encoding: 8bit 6.1-stable review patch. If anyone has any objections, please let me know. ------------------ From: Xu Yang commit b84cc80610a8ce036deb987f056ce3196ead7f1e upstream. When a port is disabled, an attached device will be disconnected. This causes a port-status-change event, which will race with hub autosuspend (if the disabled port was the only connected port on its hub), causing an immediate resume and a second autosuspend. Both of these can be avoided by adding a short delay after the call to usb_hub_set_port_power(). Below log shows what is happening: $ echo 1 > usb1-port1/disable [ 37.958239] usb 1-1: USB disconnect, device number 2 [ 37.964101] usb 1-1: unregistering device [ 37.970070] hub 1-0:1.0: hub_suspend [ 37.971305] hub 1-0:1.0: state 7 ports 1 chg 0000 evt 0002 [ 37.974412] usb usb1: bus auto-suspend, wakeup 1 [ 37.988175] usb usb1: suspend raced with wakeup event <--- [ 37.993947] usb usb1: usb auto-resume [ 37.998401] hub 1-0:1.0: hub_resume [ 38.105688] usb usb1-port1: status 0000, change 0000, 12 Mb/s [ 38.112399] hub 1-0:1.0: state 7 ports 1 chg 0000 evt 0000 [ 38.118645] hub 1-0:1.0: hub_suspend [ 38.122963] usb usb1: bus auto-suspend, wakeup 1 [ 38.200368] usb usb1: usb wakeup-resume [ 38.204982] usb usb1: usb auto-resume [ 38.209376] hub 1-0:1.0: hub_resume [ 38.213676] usb usb1-port1: status 0101 change 0001 [ 38.321552] hub 1-0:1.0: state 7 ports 1 chg 0002 evt 0000 [ 38.327978] usb usb1-port1: status 0101, change 0000, 12 Mb/s [ 38.457429] usb 1-1: new high-speed USB device number 3 using ci_hdrc Then, port change bit will be fixed to the final state and usb_clear_port_feature() can correctly clear it after this period. This will also avoid usb runtime suspend routine to run because usb_autopm_put_interface() not run yet. Fixes: f061f43d7418 ("usb: hub: port: add sysfs entry to switch port power") Cc: stable@kernel.org Signed-off-by: Xu Yang Link: https://patch.msgid.link/20260316095042.1559882-1-xu.yang_2@nxp.com Signed-off-by: Greg Kroah-Hartman --- drivers/usb/core/port.c | 1 + 1 file changed, 1 insertion(+) --- a/drivers/usb/core/port.c +++ b/drivers/usb/core/port.c @@ -111,6 +111,7 @@ static ssize_t disable_store(struct devi usb_disconnect(&port_dev->child); rc = usb_hub_set_port_power(hdev, hub, port1, !disabled); + msleep(2 * hub_power_on_good_delay(hub)); if (disabled) { usb_clear_port_feature(hdev, port1, USB_PORT_FEAT_C_CONNECTION);