Return-path: Received: from mail-yk0-f178.google.com ([209.85.160.178]:36795 "EHLO mail-yk0-f178.google.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1755600AbbJANSW convert rfc822-to-8bit (ORCPT ); Thu, 1 Oct 2015 09:18:22 -0400 MIME-Version: 1.0 From: =?UTF-8?Q?Jo=C3=A3o_Paulo_Rechi_Vita?= Date: Thu, 1 Oct 2015 09:17:42 -0400 Message-ID: (sfid-20151001_151834_830136_5247D206) Subject: rtl8821ae bisected regression between 4.1 and 4.2 To: linux-wireless Cc: Vincent Fann , Shao Fu , Larry Finger , Kalle Valo , Stable , Daniel Drake Content-Type: text/plain; charset=UTF-8 Sender: linux-wireless-owner@vger.kernel.org List-ID: Hello linux-wirelless (cc'ing stable since the original patch had cc:stable as well), I'm experiencing a CPU soft lockup while downloading when rtl8821ae is loaded (even when downloading through other adapters) on a vanilla 4.2 kernel. The problem did not happen on vanilla 4.1. Bisecting shows the first bad commit being "rtlwifi: Remove the clear interrupt routine from all drivers" (1277fa2ab2f9a624a4b0177119ca13b5fd65edd0). Reverting that commit makes the problem go away. The system is perfectly stable until I start downloading, when the UI becomes unresponsive, sometimes leading to a complete freeze. When the system does not completely freezes and I'm able to kill the download, everything seems to go back to normal after killing it, and I am able to continue to use the computer as long as I do not download anything. Most of the time either a soft or a hard lockup is detected, but not always, although the freeze always occurs. This is the kernel log with lockdep enabled (although sometimes the problem does not occur with lockdep enabled): https://gist.github.com/jprvita/3aa2c0c9a66793e1fad1 I have the laptop where this happens as a test machine sitting on my desk, so I'm available to test any patches or gather more information if needed. Please advise on how I can help debugging this further. Regards, -- João Paulo Rechi Vita http://about.me/jprvita