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 Received: from mail.kernel.org (mail.kernel.org [198.145.29.99]) by smtp.lore.kernel.org (Postfix) with ESMTP id 2C47BC433EF for ; Thu, 11 Nov 2021 22:48:59 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id 0E68161039 for ; Thu, 11 Nov 2021 22:48:59 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S233913AbhKKWv0 (ORCPT ); Thu, 11 Nov 2021 17:51:26 -0500 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:56612 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S230348AbhKKWvX (ORCPT ); Thu, 11 Nov 2021 17:51:23 -0500 Received: from bombadil.infradead.org (bombadil.infradead.org [IPv6:2607:7c80:54:e::133]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id 4C781C061766 for ; Thu, 11 Nov 2021 14:48:34 -0800 (PST) DKIM-Signature: v=1; a=rsa-sha256; q=dns/txt; c=relaxed/relaxed; d=infradead.org; s=bombadil.20210309; h=Sender:Content-Type:MIME-Version: Message-ID:Subject:Cc:To:From:Date:Reply-To:Content-Transfer-Encoding: Content-ID:Content-Description:In-Reply-To:References; bh=P8dbu6bq4K+PWUujkU4hjoft1+fqI27MatlMJ/QyGuI=; b=DIEtXFmC2F85m71vwyPLcjKOQk XjZEbHKR4s6o9R+TJFbZJAX5w6NIoGC4G7Tyr4UiU2sDuxm/bM/DqzgQfEXijaLfYzbsZMB+nW2Pg 3fS5axfaKR/QoXehw3rpT5x08XLk3pdS95g4GbvhgzZTXlpNNp6aQoUMl8nKH29W8h0noSg8OSL0n bfGMRaMuz1qL/dM15gvBb/UkqsFSNFor48hNDm5vJjOo3uKFAeVY6JWhl++NRpUh8COLKxDqePUS7 nbT7OL0ngCIQOs/4Ikle6bmn7BGmq4XLLkOsvsgEBmXO9v2HT1XAil0vxpAZBxgPPz22kmyXqe6R9 rLTU1SPQ==; Received: from mcgrof by bombadil.infradead.org with local (Exim 4.94.2 #2 (Red Hat Linux)) id 1mlIrp-008vaU-R6; Thu, 11 Nov 2021 22:48:25 +0000 Date: Thu, 11 Nov 2021 14:48:25 -0800 From: Luis Chamberlain To: mst@redhat.com, david@redhat.com, jasowang@redhat.com, virtualization@lists.linux-foundation.org, Michal Hocko , Vlastimil Babka Cc: Luis Chamberlain , linux-kernel@vger.kernel.org Subject: update_balloon_size_func blocked for more than 120 seconds Message-ID: MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline Sender: Luis Chamberlain Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org I get the following splats with a kvm guest in idle, after a few seconds it starts: [ 242.412806] INFO: task kworker/6:2:271 blockedfor more than 120 seconds. [ 242.415790] Tainted: G E 5.15.0-next-20211111 #68 [ 242.417755] "echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message. [ 242.418332] task:kworker/6:2 state:D stack: 0 pid: 271 ppid: 2 flags:0x00004000 [ 242.418954] Workqueue: events_freezable update_balloon_size_func [virtio_balloon] [ 242.419518] Call Trace: [ 242.419709] [ 242.419873] __schedule+0x2fd/0x990 [ 242.420142] schedule+0x4e/0xc0 [ 242.420382] tell_host+0xaa/0xf0 [virtio_balloon] [ 242.420757] ? do_wait_intr_irq+0xa0/0xa0 [ 242.421065] update_balloon_size_func+0x2c9/0x2e0 [virtio_balloon] [ 242.421527] process_one_work+0x1e5/0x3c0 [ 242.421833] worker_thread+0x50/0x3b0 [ 242.422204] ? rescuer_thread+0x370/0x370 [ 242.422507] kthread+0x169/0x190 [ 242.422754] ? set_kthread_struct+0x40/0x40 [ 242.423073] ret_from_fork+0x1f/0x30 [ 242.423347] And this goes on endlessly. The last one says it blocked for more than 1208 seconds. This was not happening until the last few weeks but I see no relevant recent commits for virtio_balloon, so the related change could be elsewhere. I could bisect but first I figured I'd check to see if someone already had spotted this. Luis