From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from smtp.kernel.org (aws-us-west-2-korg-mail-1.web.codeaurora.org [10.30.226.201]) (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 A5CA313B7AE for ; Wed, 8 Apr 2026 12:00:28 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.client-ip=10.30.226.201 ARC-Seal:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1775649628; cv=none; b=sPnECQ+lHT6pvkk6dpfx8dQdyhH05TYosZXwYhbxfU/Xfn23E9pP6gD+EsRzipT5d38uc+ek0ggG84IP32nTq/7GGI5VJdz0BK8YbhqX+muycOWYK8gIlYCyYpl1u9ybT3O20HuqsrPTc+g+tZaOJVffGDt3qvI68h6Pkf+t998= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1775649628; c=relaxed/simple; bh=9QHKBNw7xFH9lTmimn/ZzH6SCqH+ZjgqtSSQcYBGsN4=; h=Subject:To:Cc:From:Date:Message-ID:MIME-Version:Content-Type; b=tsUjyAlnx6fUAajA1fM03RuA+UQtCqG+oPojkrkWcBdB3T9+R16Xu+4kgEO26o9ciFoK6N5MO5K8iiX01resjFyfsO3xVbRhRMhwCWJeXuDrhQ12w6PYtBKRQyx4UakppOy9ikMgdUZoQwhV7wSMHB56LVmd9sIt/mh7CEFFKeE= ARC-Authentication-Results:i=1; smtp.subspace.kernel.org; dkim=pass (1024-bit key) header.d=linuxfoundation.org header.i=@linuxfoundation.org header.b=TFgKFYw2; arc=none smtp.client-ip=10.30.226.201 Authentication-Results: smtp.subspace.kernel.org; dkim=pass (1024-bit key) header.d=linuxfoundation.org header.i=@linuxfoundation.org header.b="TFgKFYw2" Received: by smtp.kernel.org (Postfix) with ESMTPSA id 3B327C19421; Wed, 8 Apr 2026 12:00:28 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=linuxfoundation.org; s=korg; t=1775649628; bh=9QHKBNw7xFH9lTmimn/ZzH6SCqH+ZjgqtSSQcYBGsN4=; h=Subject:To:Cc:From:Date:From; b=TFgKFYw2ll4JHd2PlJS4jZWJDybLDUifDlStcZxkJKs+8aeNcWMOCz3NW+Dqi5hny oaZWLq3NY3E75tOPMIukl7GphAFv11H0Et1FxJe1kSN1lSOrmE3VxwREr7txhtuOhn u2kvzQJ74w/SrrOCR9KZ2FZxVTEI133aHPHR69ns= Subject: FAILED: patch "[PATCH] usb: gadget: f_hid: move list and spinlock inits from bind to" failed to apply to 6.6-stable tree To: sigmaepsilon92@gmail.com,gregkh@linuxfoundation.org,stable@kernel.org Cc: From: Date: Wed, 08 Apr 2026 14:00:26 +0200 Message-ID: <2026040826-pagan-amuser-3732@gregkh> Precedence: bulk X-Mailing-List: stable@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 Content-Type: text/plain; charset=ANSI_X3.4-1968 Content-Transfer-Encoding: 8bit The patch below does not apply to the 6.6-stable tree. If someone wants it applied there, or to any other stable or longterm tree, then please email the backport, including the original git commit id to . To reproduce the conflict and resubmit, you may use the following commands: git fetch https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git/ linux-6.6.y git checkout FETCH_HEAD git cherry-pick -x 4e0a88254ad59f6c53a34bf5fa241884ec09e8b2 # git commit -s git send-email --to '' --in-reply-to '2026040826-pagan-amuser-3732@gregkh' --subject-prefix 'PATCH 6.6.y' HEAD^.. Possible dependencies: thanks, greg k-h ------------------ original commit in Linus's tree ------------------ >From 4e0a88254ad59f6c53a34bf5fa241884ec09e8b2 Mon Sep 17 00:00:00 2001 From: Michael Zimmermann Date: Tue, 31 Mar 2026 20:48:44 +0200 Subject: [PATCH] usb: gadget: f_hid: move list and spinlock inits from bind to alloc There was an issue when you did the following: - setup and bind an hid gadget - open /dev/hidg0 - use the resulting fd in EPOLL_CTL_ADD - unbind the UDC - bind the UDC - use the fd in EPOLL_CTL_DEL When CONFIG_DEBUG_LIST was enabled, a list_del corruption was reported within remove_wait_queue (via ep_remove_wait_queue). After some debugging I found out that the queues, which f_hid registers via poll_wait were the problem. These were initialized using init_waitqueue_head inside hidg_bind. So effectively, the bind function re-initialized the queues while there were still items in them. The solution is to move the initialization from hidg_bind to hidg_alloc to extend their lifetimes to the lifetime of the function instance. Additionally, I found many other possibly problematic init calls in the bind function, which I moved as well. Signed-off-by: Michael Zimmermann Cc: stable Link: https://patch.msgid.link/20260331184844.2388761-1-sigmaepsilon92@gmail.com Signed-off-by: Greg Kroah-Hartman diff --git a/drivers/usb/gadget/function/f_hid.c b/drivers/usb/gadget/function/f_hid.c index 8812ebf33d14..e5ccaec7750c 100644 --- a/drivers/usb/gadget/function/f_hid.c +++ b/drivers/usb/gadget/function/f_hid.c @@ -1262,17 +1262,8 @@ static int hidg_bind(struct usb_configuration *c, struct usb_function *f) if (status) goto fail; - spin_lock_init(&hidg->write_spinlock); hidg->write_pending = 1; hidg->req = NULL; - spin_lock_init(&hidg->read_spinlock); - spin_lock_init(&hidg->get_report_spinlock); - init_waitqueue_head(&hidg->write_queue); - init_waitqueue_head(&hidg->read_queue); - init_waitqueue_head(&hidg->get_queue); - init_waitqueue_head(&hidg->get_id_queue); - INIT_LIST_HEAD(&hidg->completed_out_req); - INIT_LIST_HEAD(&hidg->report_list); INIT_WORK(&hidg->work, get_report_workqueue_handler); hidg->workqueue = alloc_workqueue("report_work", @@ -1608,6 +1599,16 @@ static struct usb_function *hidg_alloc(struct usb_function_instance *fi) mutex_lock(&opts->lock); + spin_lock_init(&hidg->write_spinlock); + spin_lock_init(&hidg->read_spinlock); + spin_lock_init(&hidg->get_report_spinlock); + init_waitqueue_head(&hidg->write_queue); + init_waitqueue_head(&hidg->read_queue); + init_waitqueue_head(&hidg->get_queue); + init_waitqueue_head(&hidg->get_id_queue); + INIT_LIST_HEAD(&hidg->completed_out_req); + INIT_LIST_HEAD(&hidg->report_list); + device_initialize(&hidg->dev); hidg->dev.release = hidg_release; hidg->dev.class = &hidg_class;