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=-3.9 required=3.0 tests=DKIMWL_WL_HIGH,DKIM_SIGNED, DKIM_VALID,DKIM_VALID_AU,HEADER_FROM_DIFFERENT_DOMAINS,INCLUDES_PATCH, MAILING_LIST_MULTI,SPF_HELO_NONE,SPF_PASS,URIBL_BLOCKED autolearn=no 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 7A8ECC3A59B for ; Mon, 19 Aug 2019 06:27:31 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.kernel.org (Postfix) with ESMTP id 4A38020989 for ; Mon, 19 Aug 2019 06:27:31 +0000 (UTC) Authentication-Results: mail.kernel.org; dkim=pass (1024-bit key) header.d=chromium.org header.i=@chromium.org header.b="GSaTH3xq" Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1726149AbfHSG1a (ORCPT ); Mon, 19 Aug 2019 02:27:30 -0400 Received: from mail-pg1-f196.google.com ([209.85.215.196]:40168 "EHLO mail-pg1-f196.google.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1726132AbfHSG13 (ORCPT ); Mon, 19 Aug 2019 02:27:29 -0400 Received: by mail-pg1-f196.google.com with SMTP id w10so582310pgj.7 for ; Sun, 18 Aug 2019 23:27:29 -0700 (PDT) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=chromium.org; s=google; h=message-id:mime-version:content-transfer-encoding:in-reply-to :references:subject:from:cc:to:user-agent:date; bh=ySzu59s/U1eiWpVmmgYwQiavhmlNAIEAzQrYGIeZiaE=; b=GSaTH3xqIx0fcNAst0wFBoQF7XlF1iEig8cebhEWi6II6J2cfIilr4ndJNdslWehGM HNAvm+AUj6gtNMikHXIy4baLDhssNB203dRE47iqrrJIEtbc6OUsy5RoI6anw3oXb0fz H6PxtJejPSJaW83HzZBkwvE43ytx02ggIKoDI= X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20161025; h=x-gm-message-state:message-id:mime-version :content-transfer-encoding:in-reply-to:references:subject:from:cc:to :user-agent:date; bh=ySzu59s/U1eiWpVmmgYwQiavhmlNAIEAzQrYGIeZiaE=; b=PICeugANIjFtMwW73XhrK3KUjJqMs5Vqibgbf53D4eJgT3Sl9aKagzKSs78RlKZhDH K3/ZqrCh2YN/pwlyX9aQ6AiYw7CJs+Pa1tDEaRL4Sz1CIWFukjstQzaGLFRKfN7QnMkw XoZG+gzN8+mQsSdnxwI+ZQ97wGoTriS6MS8chqVLB/dcw0jaRln55NDz7XZHJMnRopIP 6PpAyAAbnSMTGFGV3uenX026mIfpyIauS/mBxamPVgx9uRzePe6tHgcC7Lu2Gx7L3l2b LXRj23aKxXOQ6urA4Q3axrdPmyxTrp/y5XrQTJaqZ1eh0BluyP5NyUIO7Hr8toyEEzYz Rc9A== X-Gm-Message-State: APjAAAVoAFeDy+xX5GVu22sJ2UKclz+Z/3qyXenA8Av44JPEoSDdg0FO 14m/iTFN2nhkBN9xXfxlhQNyabie7aMThw== X-Google-Smtp-Source: APXvYqwxh6EpDsR4gSDgYaivhvwiyY/TcdbBNxdN/wU3uNqa+Z8Ujc87bSOhINz7830RArvtp3tOoQ== X-Received: by 2002:a62:1444:: with SMTP id 65mr22259254pfu.145.1566196048820; Sun, 18 Aug 2019 23:27:28 -0700 (PDT) Received: from chromium.org ([2620:15c:202:1:fa53:7765:582b:82b9]) by smtp.gmail.com with ESMTPSA id t11sm19934188pgb.33.2019.08.18.23.27.28 (version=TLS1_3 cipher=TLS_AES_256_GCM_SHA384 bits=256/256); Sun, 18 Aug 2019 23:27:28 -0700 (PDT) Message-ID: <5d5a4150.1c69fb81.3faa2.eee8@mx.google.com> Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: quoted-printable In-Reply-To: <49fc7c64-88c0-74d0-2cb3-07986490941d@ti.com> References: <49fc7c64-88c0-74d0-2cb3-07986490941d@ti.com> Subject: Re: Suspend/Resume Broken on AM43/AM33 Platforms From: Stephen Boyd Cc: Linux-OMAP , Linux Kernel Mailing List , "Kristo, Tero" , Dave Gerlach To: Keerthy , Tony Lindgren , herbert@gondor.apana.org.au User-Agent: alot/0.8.1 Date: Sun, 18 Aug 2019 23:27:27 -0700 Sender: linux-kernel-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Quoting Keerthy (2019-08-18 21:24:58) > Hi Stephen, >=20 > commit 03a3bb7ae63150230c5de645dc95e673ebf17e1a > Author: Stephen Boyd > Date: Mon Aug 5 16:32:41 2019 -0700 >=20 > hwrng: core - Freeze khwrng thread during suspend >=20 > Commit seems to be breaking suspend/resume on TI AM43/AM33 platforms. >=20 >=20 > rtcwake: wakeup from "mem" using /dev/rtc0 at Sun Nov 18 02:12:12 2018 > [ 54.033833] PM: suspend entry (deep) > [ 54.037741] Filesystems sync: 0.000 seconds > [ 54.062730] Freezing user space processes ... (elapsed 0.001 seconds) = > done. > [ 54.071313] OOM killer disabled. > [ 54.074572] Freezing remaining freezable tasks ... > [ 74.083121] Freezing of tasks failed after 20.003 seconds (1 tasks=20 > refusing to freeze, wq_busy=3D0): > [ 74.092257] hwrng R running task 0 289 2=20 > 0x00000020 > [ 74.099511] [] (__schedule) from []=20 > (schedule+0x3c/0xc0) > [ 74.106720] [] (schedule) from []=20 > (add_hwgenerator_randomness+0xb0/0x100) > [ 74.115358] [] (add_hwgenerator_randomness) from=20 > [] (hwrng_fillfn+0xc0/0x14c [rng_core]) Thanks for the report. I suspect we need to check for freezer in add_hwgenerator_randomness(). I find it odd that there's another caller of add_hwgenerator_randomness(), but maybe the ath9k driver can be converted to some sort of hwrng driver instead of calling into the kthread directly. Anyway, can you try this patch? ---8<--- diff --git a/drivers/char/random.c b/drivers/char/random.c index 5d5ea4ce1442..e2e85ca16410 100644 --- a/drivers/char/random.c +++ b/drivers/char/random.c @@ -2429,6 +2429,7 @@ void add_hwgenerator_randomness(const char *buffer, s= ize_t count, size_t entropy) { struct entropy_store *poolp =3D &input_pool; + bool frozen =3D false; =20 if (unlikely(crng_init =3D=3D 0)) { crng_fast_load(buffer, count); @@ -2439,9 +2440,12 @@ void add_hwgenerator_randomness(const char *buffer, = size_t count, * We'll be woken up again once below random_write_wakeup_thresh, * or when the calling thread is about to terminate. */ - wait_event_interruptible(random_write_wait, kthread_should_stop() || + wait_event_interruptible(random_write_wait, + kthread_freezable_should_stop(&frozen) || ENTROPY_BITS(&input_pool) <=3D random_write_wakeup_bits); - mix_pool_bytes(poolp, buffer, count); - credit_entropy_bits(poolp, entropy); + if (!frozen) { + mix_pool_bytes(poolp, buffer, count); + credit_entropy_bits(poolp, entropy); + } } EXPORT_SYMBOL_GPL(add_hwgenerator_randomness);