From patchwork Thu Jun 16 08:38:52 2022 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Hongyu Xie X-Patchwork-Id: 12883545 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 23F79C433EF for ; Thu, 16 Jun 2022 08:39:01 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1359689AbiFPIjA (ORCPT ); Thu, 16 Jun 2022 04:39:00 -0400 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:57544 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S230045AbiFPIi6 (ORCPT ); Thu, 16 Jun 2022 04:38:58 -0400 Received: from mail-pg1-x52b.google.com (mail-pg1-x52b.google.com [IPv6:2607:f8b0:4864:20::52b]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id A05935D64F; Thu, 16 Jun 2022 01:38:57 -0700 (PDT) Received: by mail-pg1-x52b.google.com with SMTP id w29so631746pgl.8; Thu, 16 Jun 2022 01:38:57 -0700 (PDT) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=gmail.com; s=20210112; h=from:to:cc:subject:date:message-id:mime-version :content-transfer-encoding; bh=X3rs3EZNUK5eXVTg1TQXkjmyGPn0t+3fhRIQGIQTt/M=; b=FbvS3MCf0rAKnwl/9sCw7pwSbwYCdNVDEjfFetPrk9VhwkklDjNZJ0ir6f1wsVv2eW GICSBSI34Ooo7/RNmxEqX1Fv+c/JqQunH7kZJ85le2iHjbmbQLKY41SXx/azHJebANQF unrUHunbyw7Cgt4RW46OFZxjK66ENjsxzTf/AJTJ9MLB6OokjDWf5NnPxGLFXIziGU3+ XwyHKoqIvxgDHikLHBnIBLPY5wZmf2CfnWCcK5WkE7BbE/i0YeGHHQLgG6sBExcS21rZ PwRZQeuWDnA8HK5enYY8lfZ64coV8HBrhwTqo0f15JwnSmzOHszp/3UccT3J5dLxfkwt 3iGA== X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20210112; h=x-gm-message-state:from:to:cc:subject:date:message-id:mime-version :content-transfer-encoding; bh=X3rs3EZNUK5eXVTg1TQXkjmyGPn0t+3fhRIQGIQTt/M=; b=6RjC+WjUtEMdYcCYpuEzE0JT1saa10QElWfH/6Yn7Kx58XH1dL/5xKp2JAPcoEwgqu SetN66Xs+JvrErpPxbJNO3B92pcvtpaLL98WkUPXaOEcE8HgdCW2JL2Ok/CwdN1vZEep +9zLXTMudzR48fK+VRcmWVKCEJEe7Rl1i4XS1kBJGJnWxYzaGk9Uibhz4pe6/fVpurHT V7Qj2KL83tFGLP6A31z0SjBlXjlO7FNiX0HgxGa8FBYDC2YTLJGVNiujjtSnN99si9Tz YQRYHQI4y0zf9E7r7OT0jxTxxwpU46/F4EJD94LTRyC49i+dI9yuApfGtE9YfV3TVy30 aLvw== X-Gm-Message-State: AJIora+RwjQ8XQzi6bEj3QGv8WPNuesTMnq4EyzdUqbmNAKTYrhKR96W JYOefpKEpQYIJMeUDByMFr+RSMK5G//0Q1TLOYw= X-Google-Smtp-Source: AGRyM1sBmk5Q28SwAF/4hpfVX9rC42L68jrBMrgK95HRcImHgqHz8VS5YJ3nIJHsW62Z/M5IeM+yHA== X-Received: by 2002:a05:6a00:4406:b0:51c:244f:85d8 with SMTP id br6-20020a056a00440600b0051c244f85d8mr3742673pfb.36.1655368737148; Thu, 16 Jun 2022 01:38:57 -0700 (PDT) Received: from localhost ([116.128.244.169]) by smtp.gmail.com with ESMTPSA id e15-20020a63370f000000b003fdc16f5de2sm1067536pga.15.2022.06.16.01.38.56 (version=TLS1_3 cipher=TLS_AES_256_GCM_SHA384 bits=256/256); Thu, 16 Jun 2022 01:38:56 -0700 (PDT) From: Hongyu Xie X-Google-Original-From: Hongyu Xie To: mathias.nyman@intel.com, gregkh@linuxfoundation.org Cc: linux-usb@vger.kernel.org, linux-kernel@vger.kernel.org, 125707942@qq.com, wangqi@kylinos.cn, xiongxin@kylinos.cn, Hongyu Xie Subject: [PATCH v5 -next] usb: xhci: disable irq during initialization Date: Thu, 16 Jun 2022 16:38:52 +0800 Message-Id: <20220616083852.1264261-1-xiehongyu1@kylinos.cn> X-Mailer: git-send-email 2.25.1 MIME-Version: 1.0 Precedence: bulk List-ID: X-Mailing-List: linux-usb@vger.kernel.org irq is disabled in xhci_quiesce(called by xhci_halt, with bit:2 cleared in USBCMD register), but xhci_run(called by usb_add_hcd) re-enable it. It's possible that you will receive thousands of interrupt requests after initialization for 2.0 roothub. And you will get a lot of warning like, "xHCI dying, ignoring interrupt. Shouldn't IRQs be disabled?". This amount of interrupt requests will cause the entire system to freeze. This problem was first found on a device with ASM2142 host controller on it. Signed-off-by: Hongyu Xie --- v5: remove reported by test robot v4: fix compile err reported by test robot v3: - enabling interrupt right before setting Run/Stop bit - spin_lock_irqsave to prevent receiving irqs in the small window according to Mathias's suggestion v2: fix compile error drivers/usb/host/xhci.c | 41 +++++++++++++++++++++++++++-------------- 1 file changed, 27 insertions(+), 14 deletions(-) diff --git a/drivers/usb/host/xhci.c b/drivers/usb/host/xhci.c index 9ac56e9ffc64..1344cc566338 100644 --- a/drivers/usb/host/xhci.c +++ b/drivers/usb/host/xhci.c @@ -611,15 +611,41 @@ static int xhci_init(struct usb_hcd *hcd) static int xhci_run_finished(struct xhci_hcd *xhci) { + unsigned long flags; + u32 temp; + + /* Prevent receiving irqs in the small window between enabling interrupt + * and setting Run/Stop bit + */ + spin_lock_irqsave(&xhci->lock, flags); + + /* Enable interrupt right before setting Run/Stop bit according to spec + * 4.2 + */ + /* Set the HCD state before we enable the irqs */ + temp = readl(&xhci->op_regs->command); + temp |= (CMD_EIE); + xhci_dbg_trace(xhci, trace_xhci_dbg_init, + "// Enable interrupts, cmd = 0x%x.", temp); + writel(temp, &xhci->op_regs->command); + + temp = readl(&xhci->ir_set->irq_pending); + xhci_dbg_trace(xhci, trace_xhci_dbg_init, + "// %s %p by writing 0x%x %s", + "Enabling event ring interrupter", + "to irq_pending", xhci->ir_set, + (unsigned int) ER_IRQ_ENABLE(temp)); + writel(ER_IRQ_ENABLE(temp), &xhci->ir_set->irq_pending); if (xhci_start(xhci)) { xhci_halt(xhci); + spin_unlock_irqrestore(&xhci->lock, flags); return -ENODEV; } xhci->cmd_ring_state = CMD_RING_STATE_RUNNING; if (xhci->quirks & XHCI_NEC_HOST) xhci_ring_cmd_db(xhci); - + spin_unlock_irqrestore(&xhci->lock, flags); return 0; } @@ -668,19 +694,6 @@ int xhci_run(struct usb_hcd *hcd) temp |= (xhci->imod_interval / 250) & ER_IRQ_INTERVAL_MASK; writel(temp, &xhci->ir_set->irq_control); - /* Set the HCD state before we enable the irqs */ - temp = readl(&xhci->op_regs->command); - temp |= (CMD_EIE); - xhci_dbg_trace(xhci, trace_xhci_dbg_init, - "// Enable interrupts, cmd = 0x%x.", temp); - writel(temp, &xhci->op_regs->command); - - temp = readl(&xhci->ir_set->irq_pending); - xhci_dbg_trace(xhci, trace_xhci_dbg_init, - "// Enabling event ring interrupter %p by writing 0x%x to irq_pending", - xhci->ir_set, (unsigned int) ER_IRQ_ENABLE(temp)); - writel(ER_IRQ_ENABLE(temp), &xhci->ir_set->irq_pending); - if (xhci->quirks & XHCI_NEC_HOST) { struct xhci_command *command;