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 5B3E3C433F5 for ; Wed, 20 Oct 2021 06:01:31 +0000 (UTC) Received: from kanga.kvack.org (kanga.kvack.org [205.233.56.17]) by mail.kernel.org (Postfix) with ESMTP id D30AE6115A for ; Wed, 20 Oct 2021 06:01:30 +0000 (UTC) DMARC-Filter: OpenDMARC Filter v1.4.1 mail.kernel.org D30AE6115A Authentication-Results: mail.kernel.org; dmarc=fail (p=reject dis=none) header.from=google.com Authentication-Results: mail.kernel.org; spf=pass smtp.mailfrom=kvack.org Received: by kanga.kvack.org (Postfix) id 28556900002; Wed, 20 Oct 2021 02:01:30 -0400 (EDT) Received: by kanga.kvack.org (Postfix, from userid 40) id 2355F6B0072; Wed, 20 Oct 2021 02:01:30 -0400 (EDT) X-Delivered-To: int-list-linux-mm@kvack.org Received: by kanga.kvack.org (Postfix, from userid 63042) id 12438900002; Wed, 20 Oct 2021 02:01:30 -0400 (EDT) X-Delivered-To: linux-mm@kvack.org Received: from forelay.hostedemail.com (smtprelay0035.hostedemail.com [216.40.44.35]) by kanga.kvack.org (Postfix) with ESMTP id 02F316B0071 for ; Wed, 20 Oct 2021 02:01:30 -0400 (EDT) Received: from smtpin25.hostedemail.com (10.5.19.251.rfc1918.com [10.5.19.251]) by forelay02.hostedemail.com (Postfix) with ESMTP id B94B22BC35 for ; Wed, 20 Oct 2021 06:01:29 +0000 (UTC) X-FDA: 78715768698.25.B946C5E Received: from mail-oi1-f179.google.com (mail-oi1-f179.google.com [209.85.167.179]) by imf10.hostedemail.com (Postfix) with ESMTP id 62F676001AB0 for ; Wed, 20 Oct 2021 06:01:25 +0000 (UTC) Received: by mail-oi1-f179.google.com with SMTP id u69so8363892oie.3 for ; Tue, 19 Oct 2021 23:01:29 -0700 (PDT) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=google.com; s=20210112; h=mime-version:references:in-reply-to:from:date:message-id:subject:to :cc; bh=IIod1o3qhCZvdW0ahsuaYBYhDgjj8nBMGLLNc7+K8Sw=; b=ZssLsRHBs4knpZ/LNOGmB6tMsO7Vf8u3B+7q4N/kKhDJ+qFdXnqnTp1l0TdZ6AGLXg eCEIQMclebzzVTUemUlS2Nr2qEs8vKNOfmBfh+bIdPvdWQpSmAE5IRSnvJ+ZMVo27Mqz 2sWXtztztjlj1Z+Dlt/8yNncFRd6KxlysKCaatYnrSdmdgKjjaa4LZZxRMIjG1BtmDkw LRxLyS+VPGvn6fQhbllcntcVt7j1ZewPEeaaUrvMRrRsv4tpoXa7fw0uqBSBNtWniPXm JriYxB5AwpwqKFEleoGSEZLZWw2KGeNyZBqMGUs4Ea60g3hCAo8bFlW1p3SPzuzTGzRp WCnA== X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20210112; h=x-gm-message-state:mime-version:references:in-reply-to:from:date :message-id:subject:to:cc; bh=IIod1o3qhCZvdW0ahsuaYBYhDgjj8nBMGLLNc7+K8Sw=; b=sloKglt96BzFMi4QMOZfTZs46AvsL2dJZPc5CkTc2BNzfCpTSd360QOCyJMB4i7Tgo A/Ww2G301+CC9ygYQDXb1I656FyZIo5RTbj26dfKzgEcCREg0ZjxZVkRSohumbNwWXue 9ETKzXQVozhYmI8PHc2jqT+PB88KO5YfFUPWLuFW30dXMaMmuxGQzTX3suSZl8dayZjO VPKDQ2w/UzmivZ1w0pWh4dZwH3zDr9j+oMglQc6gJx+IcnW59sx4ZxCxEcXJdw0O+vJO IqOdZCyM1kYR6lhRJq/qRH21YZFF538lXR4QyGWb950SPfOkCTwETu6alkmNbuVUAXRY VB3A== X-Gm-Message-State: AOAM531MyOE8VPD7w9iMomzgEYELn6Y2Fpz1ylX2yl2OUc/y7LlKONGE oudYdy2D4loT+OXcrC1lY/gFE7QoREoVv3aag/GrnA== X-Google-Smtp-Source: ABdhPJzd5qvCHYDQgSADJn7obJ/Nig85wI9Xg4OLC0YNlR1f8iwE9Xx9T55lvywUl29R/cQIuk2QANtojG3mUeF0n6s= X-Received: by 2002:a05:6808:191c:: with SMTP id bf28mr7691641oib.7.1634709688231; Tue, 19 Oct 2021 23:01:28 -0700 (PDT) MIME-Version: 1.0 References: In-Reply-To: From: Marco Elver Date: Wed, 20 Oct 2021 08:00:00 +0200 Message-ID: Subject: Re: BUG: soft lockup in __kmalloc_node() with KFENCE enabled To: Andrea Righi Cc: Dmitry Vyukov , Alexander Potapenko , kasan-dev@googlegroups.com, linux-mm@kvack.org, linux-kernel@vger.kernel.org Content-Type: text/plain; charset="UTF-8" X-Stat-Signature: ispexp9znzis3cfzkfc61zb3m48e8yw3 Authentication-Results: imf10.hostedemail.com; dkim=pass header.d=google.com header.s=20210112 header.b=ZssLsRHB; spf=pass (imf10.hostedemail.com: domain of elver@google.com designates 209.85.167.179 as permitted sender) smtp.mailfrom=elver@google.com; dmarc=pass (policy=reject) header.from=google.com X-Rspamd-Server: rspam02 X-Rspamd-Queue-Id: 62F676001AB0 X-HE-Tag: 1634709685-129432 X-Bogosity: Ham, tests=bogofilter, spamicity=0.000000, version=1.2.4 Sender: owner-linux-mm@kvack.org Precedence: bulk X-Loop: owner-majordomo@kvack.org List-ID: On Mon, 11 Oct 2021 at 16:42, Andrea Righi wrote: > On Mon, Oct 11, 2021 at 12:03:52PM +0200, Marco Elver wrote: > > On Mon, 11 Oct 2021 at 11:53, Andrea Righi wrote: > > > On Mon, Oct 11, 2021 at 11:23:32AM +0200, Andrea Righi wrote: > > > ... > > > > > You seem to use the default 20s stall timeout. FWIW syzbot uses 160 > > > > > secs timeout for TCG emulation to avoid false positive warnings: > > > > > https://github.com/google/syzkaller/blob/838e7e2cd9228583ca33c49a39aea4d863d3e36d/dashboard/config/linux/upstream-arm64-kasan.config#L509 > > > > > There are a number of other timeouts raised as well, some as high as > > > > > 420 seconds. > > > > > > > > I see, I'll try with these settings and see if I can still hit the soft > > > > lockup messages. > > > > > > Still getting soft lockup messages even with the new timeout settings: > > > > > > [ 462.663766] watchdog: BUG: soft lockup - CPU#2 stuck for 430s! [systemd-udevd:168] > > > [ 462.755758] watchdog: BUG: soft lockup - CPU#3 stuck for 430s! [systemd-udevd:171] > > > [ 924.663765] watchdog: BUG: soft lockup - CPU#2 stuck for 861s! [systemd-udevd:168] > > > [ 924.755767] watchdog: BUG: soft lockup - CPU#3 stuck for 861s! [systemd-udevd:171] > > > > The lockups are expected if you're hitting the TCG bug I linked. Try > > to pass '-enable-kvm' to the inner qemu instance (my bad if you > > already have), assuming that's somehow easy to do. > > If I add '-enable-kvm' I can triggering other random panics (almost > immediately), like this one for example: Just FYI: https://lkml.kernel.org/r/20211019102524.2807208-2-elver@google.com But you can already flip that switch in your config (CONFIG_KFENCE_STATIC_KEYS=n), which we recommend as a default now. As a side-effect it'd also make your QEMU TCG tests pass.