From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: X-Spam-Checker-Version: SpamAssassin 3.4.0 (2014-02-07) on aws-us-west-2-korg-lkml-1.web.codeaurora.org X-Spam-Level: X-Spam-Status: No, score=-9.8 required=3.0 tests=HEADER_FROM_DIFFERENT_DOMAINS, INCLUDES_PATCH,MAILING_LIST_MULTI,SIGNED_OFF_BY,SPF_HELO_NONE,SPF_PASS, USER_AGENT_GIT autolearn=ham autolearn_force=no version=3.4.0 Received: from mail.kernel.org (mail.kernel.org [198.145.29.99]) by smtp.lore.kernel.org (Postfix) with ESMTP id 79B9AC433E0 for ; Fri, 15 May 2020 04:15:49 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id 4BD8A206F1 for ; Fri, 15 May 2020 04:15:49 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1726242AbgEOEPs (ORCPT ); Fri, 15 May 2020 00:15:48 -0400 Received: from mga09.intel.com ([134.134.136.24]:13161 "EHLO mga09.intel.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1725616AbgEOEPs (ORCPT ); Fri, 15 May 2020 00:15:48 -0400 IronPort-SDR: yvDlW/4+FWbM5MqhgKyFCSgUJDIXvDmyoCRPYkLVEyhwT5jypkSrYlKX5TiUEZhwDwxcHrSotw sjfTa+wGgcSQ== X-Amp-Result: SKIPPED(no attachment in message) X-Amp-File-Uploaded: False Received: from fmsmga008.fm.intel.com ([10.253.24.58]) by orsmga102.jf.intel.com with ESMTP/TLS/ECDHE-RSA-AES256-GCM-SHA384; 14 May 2020 21:15:47 -0700 IronPort-SDR: h21gBEuc1WSXsq8NSuif0vOqjl206dBqGYH1UlpT5XC4yIptNdSmDunNfMV8M5pQJWRmKg1I1p 4q4+5QVdf89A== X-ExtLoop1: 1 X-IronPort-AV: E=Sophos;i="5.73,393,1583222400"; d="scan'208";a="253683839" Received: from brentlu-desk0.itwn.intel.com ([10.5.253.11]) by fmsmga008.fm.intel.com with ESMTP; 14 May 2020 21:15:42 -0700 From: Brent Lu To: alsa-devel@alsa-project.org Cc: Jaroslav Kysela , Takashi Iwai , Baolin Wang , Arnd Bergmann , Greg Kroah-Hartman , Richard Fontana , Thomas Gleixner , Brent Lu , paulhsia , linux-kernel@vger.kernel.org Subject: [PATCH] ALSA: pcm: fix incorrect hw_base increase Date: Fri, 15 May 2020 12:09:39 +0800 Message-Id: <1589515779-20987-1-git-send-email-brent.lu@intel.com> X-Mailer: git-send-email 2.7.4 Sender: linux-kernel-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org The hw_base will be increased by runtime->buffer_size frames unconditionally if the runtime->status->hw_ptr is not updated for over half of buffer time. As the hw_base increases, so does the runtime->status->hw_ptr which could lead to invalid return value when user space program calls snd_pcm_avail() function. By updating runtime->hw_ptr_jiffies each time the HWSYNC is called, the hw_base will keep the same when buffer stall happens, so does the hw_ptr. Signed-off-by: Brent Lu --- sound/core/pcm_lib.c | 1 + 1 file changed, 1 insertion(+) diff --git a/sound/core/pcm_lib.c b/sound/core/pcm_lib.c index 872a852..d531e1b 100644 --- a/sound/core/pcm_lib.c +++ b/sound/core/pcm_lib.c @@ -433,6 +433,7 @@ static int snd_pcm_update_hw_ptr0(struct snd_pcm_substream *substream, no_delta_check: if (runtime->status->hw_ptr == new_hw_ptr) { + runtime->hw_ptr_jiffies = curr_jiffies; update_audio_tstamp(substream, &curr_tstamp, &audio_tstamp); return 0; } -- 2.7.4