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 1179A251788; Tue, 29 Apr 2025 16:54:06 +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=1745945646; cv=none; b=K3kY25YVxTgVUp3vlimTEbaE0T7Ac+ciiT65nd4OXZ4fupbqPl3vm3kRhwplr0XYuog8IUsadVlGxfvdHrVvtMfBhFyoZ5bZdD9AC5YPT6F9QKjOuUIdwYUkks+5agYhBywCJgEiy3z5Qi3PmB5nBnSigsVbjAaxNemrr5Laog4= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1745945646; c=relaxed/simple; bh=Cge39suPAAIrdX2qfTX0t/OxJJIwM18xGaCkBKJjKQY=; h=From:To:Cc:Subject:Date:Message-ID:In-Reply-To:References: MIME-Version; b=JP5hkHuZYUa71Z6vjiBWSpk7b5HCa1ADarSWXIsPh/0Hr4kLz1NCqYVyXhZOQwU4VGhNGtgHJ3PpIXvVLMfLwgNCGtfHTd6dA1BSr8LEU2SoPwmZMw+bWk84P+IfTslMSRBLke3E/4anVfpp160wsun09JNYDgQnXp+PRYaIjPA= ARC-Authentication-Results:i=1; smtp.subspace.kernel.org; dkim=pass (1024-bit key) header.d=linuxfoundation.org header.i=@linuxfoundation.org header.b=0ScfW/zW; 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="0ScfW/zW" Received: by smtp.kernel.org (Postfix) with ESMTPSA id 8D22DC4CEE9; Tue, 29 Apr 2025 16:54:05 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=linuxfoundation.org; s=korg; t=1745945645; bh=Cge39suPAAIrdX2qfTX0t/OxJJIwM18xGaCkBKJjKQY=; h=From:To:Cc:Subject:Date:In-Reply-To:References:From; b=0ScfW/zWLe7MGb48WhPTipGe6S+a66B9p6O/pd3A1Wr/32dV1hBV+OPEkShytj+0j m09Zq1iEAQVnHQ+jG0ABXmN0+8AzstKj7BmRD81tWB1iaEaqK/eRTmAIjC+NdYhbkV KeEWsHVfXDu+0jbJ3zBVh7u6VLyAqdFhhuQcTZi8= From: Greg Kroah-Hartman To: stable@vger.kernel.org Cc: Greg Kroah-Hartman , patches@lists.linux.dev, stable , Ralph Siemsen , Peter Chen , Sebastian Andrzej Siewior Subject: [PATCH 5.4 153/179] usb: cdns3: Fix deadlock when using NCM gadget Date: Tue, 29 Apr 2025 18:41:34 +0200 Message-ID: <20250429161055.573171960@linuxfoundation.org> X-Mailer: git-send-email 2.49.0 In-Reply-To: <20250429161049.383278312@linuxfoundation.org> References: <20250429161049.383278312@linuxfoundation.org> User-Agent: quilt/0.68 X-stable: review X-Patchwork-Hint: ignore Precedence: bulk X-Mailing-List: stable@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 Content-Transfer-Encoding: 8bit 5.4-stable review patch. If anyone has any objections, please let me know. ------------------ From: Ralph Siemsen commit a1059896f2bfdcebcdc7153c3be2307ea319501f upstream. The cdns3 driver has the same NCM deadlock as fixed in cdnsp by commit 58f2fcb3a845 ("usb: cdnsp: Fix deadlock issue during using NCM gadget"). Under PREEMPT_RT the deadlock can be readily triggered by heavy network traffic, for example using "iperf --bidir" over NCM ethernet link. The deadlock occurs because the threaded interrupt handler gets preempted by a softirq, but both are protected by the same spinlock. Prevent deadlock by disabling softirq during threaded irq handler. Cc: stable Fixes: 7733f6c32e36 ("usb: cdns3: Add Cadence USB3 DRD Driver") Signed-off-by: Ralph Siemsen Acked-by: Peter Chen Reviewed-by: Sebastian Andrzej Siewior Link: https://lore.kernel.org/r/20250318-rfs-cdns3-deadlock-v2-1-bfd9cfcee732@linaro.org Signed-off-by: Greg Kroah-Hartman --- drivers/usb/cdns3/gadget.c | 2 ++ 1 file changed, 2 insertions(+) --- a/drivers/usb/cdns3/gadget.c +++ b/drivers/usb/cdns3/gadget.c @@ -1920,6 +1920,7 @@ static int cdns3_gadget_ep_disable(struc "%s is already disabled\n", priv_ep->name)) return 0; + local_bh_disable(); spin_lock_irqsave(&priv_dev->lock, flags); trace_cdns3_gadget_ep_disable(priv_ep); @@ -1976,6 +1977,7 @@ static int cdns3_gadget_ep_disable(struc priv_ep->flags &= ~EP_ENABLED; spin_unlock_irqrestore(&priv_dev->lock, flags); + local_bh_enable(); return ret; }