Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1758387Ab3EWKpf (ORCPT ); Thu, 23 May 2013 06:45:35 -0400 Received: from mail-ie0-f173.google.com ([209.85.223.173]:49100 "EHLO mail-ie0-f173.google.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1758334Ab3EWKp3 (ORCPT ); Thu, 23 May 2013 06:45:29 -0400 MIME-Version: 1.0 In-Reply-To: References: <20130521230332.GC12713@redhat.com> <519D1668.6000601@zytor.com> <20130522200012.GA15456@redhat.com> <20130523033911.GA9411@redhat.com> Date: Thu, 23 May 2013 18:45:29 +0800 Message-ID: Subject: Re: microcode loading got really slow. From: Ming Lei To: Takashi Iwai Cc: Dave Jones , "H. Peter Anvin" , Linux Kernel , x86@kernel.org, fenghua.yu@intel.com Content-Type: text/plain; charset=ISO-8859-1 Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Content-Length: 1440 Lines: 37 On Thu, May 23, 2013 at 6:36 PM, Takashi Iwai wrote: > > No, f/w loader always fall back to user mode helper, as long as its > support is built in. And doing that for microcode driver in that code > path isn't only superfluous but also broken due to request_firmware > call in module init. Firstly, it is not good to do this since some distributions doesn't support direct loading and doesn't have udevd(such as, android). Secondly, returning failure from request_firmware_direct() doesn't mean the firmware doesn't exist since distribution may put the firmware other where. Anyway, this example is very specific(no firmware can be accepted), and request_firmware_nowait() should be OK for the situation. > >> wrt. this problem, I think we >> need to know why the direct loading is failed. > > The reason is obvious: the requested f/w file doesn't exist. > And it's fine, because the microcode update is an optional operation. > If no f/w file is found, it's not handled as an error. It just means > that no need to update, continuing to work. OK, as said above, the example is very specific, and might be workarounded by request_firmware_nowait(). Thanks, -- Ming Lei -- To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to majordomo@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/