From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from mgamail.intel.com (mgamail.intel.com [192.198.163.8]) (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 058B62D1907; Fri, 3 Jul 2026 14:40:48 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.client-ip=192.198.163.8 ARC-Seal:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1783089652; cv=none; b=V0eMfZbI2XXfutI/zAFQE9AQVUQMgyLRZQHl0hDevAixjUI7X48HN/dEGwy7M7YXk9Mwmw1bPoaqWpiXCJeWcLBqVPgbx/s5cZuoy1L1k7VKCez/5e1eetfgl7ea4XDqsxB0XVu3djSkQxJeetPk1VpaXOpCF4sm9gBfJnZnV04= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1783089652; c=relaxed/simple; bh=Xt7iwaN9giBkTYqozXTifVqHbcD9rYw/AGaOQHCnANw=; h=From:To:Cc:Subject:Date:Message-ID:In-Reply-To:References: MIME-Version:Content-Type; b=PdZYer1Lsgc0pvDzMHZVMfCUd0D46HlOIKN5KBKkavP26RPl1W5PA1mNbvlJNjhGgKlJ4vNUrRVhcUs8y2WBgmsGsuEOg4XZdRleEzVLtvAfCxxrnIq1jIakUfnG1g5mBVJXszVVeN7+rqaFCrEe3QmeSd7ayDXTuHiHHYbh/2I= ARC-Authentication-Results:i=1; smtp.subspace.kernel.org; dmarc=pass (p=none dis=none) header.from=linux.intel.com; spf=pass smtp.mailfrom=linux.intel.com; dkim=pass (2048-bit key) header.d=intel.com header.i=@intel.com header.b=FRwmyLb4; arc=none smtp.client-ip=192.198.163.8 Authentication-Results: smtp.subspace.kernel.org; dmarc=pass (p=none dis=none) header.from=linux.intel.com Authentication-Results: smtp.subspace.kernel.org; spf=pass smtp.mailfrom=linux.intel.com Authentication-Results: smtp.subspace.kernel.org; dkim=pass (2048-bit key) header.d=intel.com header.i=@intel.com header.b="FRwmyLb4" DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=intel.com; i=@intel.com; q=dns/txt; s=Intel; t=1783089649; x=1814625649; h=from:to:cc:subject:date:message-id:in-reply-to: references:mime-version:content-transfer-encoding; bh=Xt7iwaN9giBkTYqozXTifVqHbcD9rYw/AGaOQHCnANw=; b=FRwmyLb4rGuyot435o5bG6XCcCgmNElJR1O3ZcSiuvfDMpQ0+QqcxAQ7 Et9c118HSHhk1aOki0JgKmhW//fxRQsYzz70wjZq7s2YqASGpXgK6nNMN yFFW66tED2/DNeAjslAjBtQ3v3oocAYqA786Ko3fV+qQYtJau7u6abY6m 9b0V0NHpaaBoeqVT1WeRAVrIlcji1dDrncrj5J9oZKYD6u+U226zvK0da CiOxNPlBfik38MesnJB65MUDEZagYA9IvzNOiqpwyXQoqQB0TALZWZUYL Ql+cNMi0sZTZxPiLcOLUjuHVxbGBxzjn9gFNCMKj5RCJxGxtPLeWuqvwb g==; X-CSE-ConnectionGUID: k6X51gXbRj+5N8U5QryaDQ== X-CSE-MsgGUID: XCM52f43QjK93VPL9STsDg== X-IronPort-AV: E=McAfee;i="6800,10657,11835"; a="101388363" X-IronPort-AV: E=Sophos;i="6.25,145,1779174000"; d="scan'208";a="101388363" Received: from orviesa008.jf.intel.com ([10.64.159.148]) by fmvoesa102.fm.intel.com with ESMTP/TLS/ECDHE-RSA-AES256-GCM-SHA384; 03 Jul 2026 07:40:48 -0700 X-CSE-ConnectionGUID: ewbP/Hv5QVeqbVxRWbcP9g== X-CSE-MsgGUID: YomxnCEcRbSCC/0I+QL1oQ== X-ExtLoop1: 1 X-IronPort-AV: E=Sophos;i="6.25,145,1779174000"; d="scan'208";a="252662617" Received: from ijarvine-desk1.ger.corp.intel.com (HELO mnyman-desk.intel.com) ([10.245.245.154]) by orviesa008-auth.jf.intel.com with ESMTP/TLS/ECDHE-RSA-AES256-GCM-SHA384; 03 Jul 2026 07:40:47 -0700 From: Mathias Nyman To: Cc: , =?UTF-8?q?=E8=83=A1=E8=BF=9E=E5=8B=A4?= , stable@vger.kernel.org, Mathias Nyman Subject: [PATCH 2/2] usb: xhci: Fix sleep in atomic context in xhci_free_streams() Date: Fri, 3 Jul 2026 17:40:33 +0300 Message-ID: <20260703144033.483286-3-mathias.nyman@linux.intel.com> X-Mailer: git-send-email 2.43.0 In-Reply-To: <20260703144033.483286-1-mathias.nyman@linux.intel.com> References: <20260703144033.483286-1-mathias.nyman@linux.intel.com> Precedence: bulk X-Mailing-List: linux-usb@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 8bit From: 胡连勤 When a USB device with active stream endpoints is disconnected, xhci_free_streams() is called from the hub_event workqueue to free the stream resources. It calls xhci_free_stream_info() while holding xhci->lock with irqs disabled. xhci_free_stream_info() invokes xhci_free_stream_ctx(), which calls dma_free_coherent() for large stream context arrays. dma_free_coherent() can sleep (e.g. via vunmap), triggering a BUG when called from atomic context. Call trace: dma_free_attrs+0x174/0x220 xhci_free_stream_info+0xd0/0x11c xhci_free_streams+0x278/0x37c usb_free_streams+0x98/0xc0 usb_unbind_interface+0x1b8/0x2f8 device_release_driver_internal+0x1d4/0x2cc device_release_driver+0x18/0x28 bus_remove_device+0x160/0x1a4 device_del+0x1ec/0x350 usb_disable_device+0x98/0x214 usb_disconnect+0xf0/0x35c hub_event+0xab4/0x19ec process_one_work+0x278/0x63c Fix this by saving the stream_info pointers and clearing the ep references under the lock, then calling xhci_free_stream_info() outside the lock where sleeping is allowed. Fixes: 8df75f42f8e6 ("USB: xhci: Add memory allocation for USB3 bulk streams.") Cc: stable@vger.kernel.org Signed-off-by: Lianqin Hu Signed-off-by: Mathias Nyman --- drivers/usb/host/xhci.c | 11 ++++++++++- 1 file changed, 10 insertions(+), 1 deletion(-) diff --git a/drivers/usb/host/xhci.c b/drivers/usb/host/xhci.c index 6922cc5496c1..f44ccee5fa07 100644 --- a/drivers/usb/host/xhci.c +++ b/drivers/usb/host/xhci.c @@ -3785,6 +3785,7 @@ static int xhci_free_streams(struct usb_hcd *hcd, struct usb_device *udev, struct xhci_virt_device *vdev; struct xhci_command *command; struct xhci_input_control_ctx *ctrl_ctx; + struct xhci_stream_info *stream_info[EP_CTX_PER_DEV]; unsigned int ep_index; unsigned long flags; u32 changed_ep_bitmask; @@ -3845,10 +3846,15 @@ static int xhci_free_streams(struct usb_hcd *hcd, struct usb_device *udev, if (ret < 0) return ret; + /* + * dma_free_coherent() called by xhci_free_stream_info() may sleep, + * so save stream_info pointers and clear references under lock, + * then free the memory outside lock. + */ spin_lock_irqsave(&xhci->lock, flags); for (i = 0; i < num_eps; i++) { ep_index = xhci_get_endpoint_index(&eps[i]->desc); - xhci_free_stream_info(xhci, vdev->eps[ep_index].stream_info); + stream_info[i] = vdev->eps[ep_index].stream_info; vdev->eps[ep_index].stream_info = NULL; /* FIXME Unset maxPstreams in endpoint context and * update deq ptr to point to normal string ring. @@ -3858,6 +3864,9 @@ static int xhci_free_streams(struct usb_hcd *hcd, struct usb_device *udev, } spin_unlock_irqrestore(&xhci->lock, flags); + for (i = 0; i < num_eps; i++) + xhci_free_stream_info(xhci, stream_info[i]); + return 0; } -- 2.43.0