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 vger.kernel.org (vger.kernel.org [23.128.96.18]) by smtp.lore.kernel.org (Postfix) with ESMTP id 7FBCEC88CB2 for ; Mon, 12 Jun 2023 16:45:14 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S235548AbjFLQpN (ORCPT ); Mon, 12 Jun 2023 12:45:13 -0400 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:42796 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S229716AbjFLQpI (ORCPT ); Mon, 12 Jun 2023 12:45:08 -0400 Received: from mail-il1-x12c.google.com (mail-il1-x12c.google.com [IPv6:2607:f8b0:4864:20::12c]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id 322BBE64 for ; Mon, 12 Jun 2023 09:45:07 -0700 (PDT) Received: by mail-il1-x12c.google.com with SMTP id e9e14a558f8ab-33d0c740498so2801275ab.0 for ; Mon, 12 Jun 2023 09:45:07 -0700 (PDT) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=kernel-dk.20221208.gappssmtp.com; s=20221208; t=1686588306; x=1689180306; h=content-transfer-encoding:in-reply-to:from:references:cc:to :content-language:subject:user-agent:mime-version:date:message-id :from:to:cc:subject:date:message-id:reply-to; bh=1dwr8T1zkMzPdbUd2/C0KhHZJoiNvIRLyDbwZLM1weg=; b=ixfU/+ld6JbLaxzASoLYN+vemV1T75PcyCMZA9mtOdzOlRIXtUk9iXaqOkXeYsiTEP pJIW3QncVsHzGK3Gwq35rm8KCiQEQ3cbwV+EFhXZTH346ISnVWYyxUjDfZUD5G7dA3ne /VIsQYPYvwcO9InKvG/zmZS65GHL7nIajl7sCEhqWecYXTdNDRcz1ulub+UvX9bqqz88 8mWNZvC1Za/lvUqqeL7WNr5fWX9rlcN7N8TwmYAOqoy5u9RxiR42FHjN8GTWijpV+VOY OVGhnwkTzJvyOZuPgjAVQouNCYhQgbDL+tT47Rzuxg7fwi7gEuoRdZu8kbB57zpCFv0D QzjQ== X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20221208; t=1686588306; x=1689180306; h=content-transfer-encoding:in-reply-to:from:references:cc:to :content-language:subject:user-agent:mime-version:date:message-id :x-gm-message-state:from:to:cc:subject:date:message-id:reply-to; bh=1dwr8T1zkMzPdbUd2/C0KhHZJoiNvIRLyDbwZLM1weg=; b=BTPnx4sngaXSTAa/19Nv22bzjf2Blhl/hDkYm5hxgkmDBNfQBshyXij2iXLbwPIwV/ Wvk3fwF5SshCX2MQx8ZVwu6f8T5yAZjvpBn3Rzy7W9W3NAFGx3pScHZXIMtFteXB6qXc 1aEfR94NcPsqFZDPPfFGITICA/oeU1ZkA347908tVLtW0R7g2PjtrCL2VlXN8Wa/8Wl4 JZ0Ey4bmYxIKMFT9XeV6Wpamwcy47Eo4uI4CxRycu9X2g5tT6pMs7gGFORPpT8hg3KzE /8oMF97n6Dt7shTb1hJ0LlS2jNvnbYmMRuZM9tNmdMLOELdSUXyHUqt9BzyYlyWohuR4 7TgQ== X-Gm-Message-State: AC+VfDwbnC3sLR6jAfGXNL573WgX1D2sj6au1DFujS/k1WBBvdLXhXcs Phig9yraMe/vOtP5iyH1126NeA== X-Google-Smtp-Source: ACHHUZ4MFEV97yKO9ZXG1inL46usfPlNG2FWIs0Wnbs4QZrmsGOvLnhRlzx7JrGRs82qQSyNrB6pMw== X-Received: by 2002:a6b:690a:0:b0:77a:ee79:652 with SMTP id e10-20020a6b690a000000b0077aee790652mr4620075ioc.1.1686588306591; Mon, 12 Jun 2023 09:45:06 -0700 (PDT) Received: from [192.168.1.94] ([96.43.243.2]) by smtp.gmail.com with ESMTPSA id e10-20020a02a78a000000b0041a8df29ad7sm2783897jaj.38.2023.06.12.09.45.05 (version=TLS1_3 cipher=TLS_AES_128_GCM_SHA256 bits=128/128); Mon, 12 Jun 2023 09:45:06 -0700 (PDT) Message-ID: <212a190c-f81e-2876-cf14-6d1e37d47192@kernel.dk> Date: Mon, 12 Jun 2023 10:45:05 -0600 MIME-Version: 1.0 User-Agent: Mozilla/5.0 (X11; Linux aarch64; rv:102.0) Gecko/20100101 Thunderbird/102.11.0 Subject: Re: [6.5-rc5 regression] core dump hangs (was Re: [Bug report] fstests generic/051 (on xfs) hang on latest linux v6.5-rc5+) Content-Language: en-US To: Linus Torvalds Cc: "Darrick J. Wong" , Dave Chinner , Zorro Lang , linux-xfs@vger.kernel.org, "Eric W. Biederman" , Mike Christie , "Michael S. Tsirkin" , linux-kernel@vger.kernel.org References: <20230611124836.whfktwaumnefm5z5@zlang-mailbox> <20230612015145.GA11441@frogsfrogsfrogs> <20230612153629.GA11427@frogsfrogsfrogs> <13d9e4f2-17c5-0709-0cc0-6f92bfe9f30d@kernel.dk> From: Jens Axboe In-Reply-To: Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 7bit Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On 6/12/23 10:42?AM, Linus Torvalds wrote: > On Mon, Jun 12, 2023 at 9:38?AM Jens Axboe wrote: >> >> Quick peek would suggest that it's because io-wq clears PF_IO_WORKER on >> exit, and now we fail the check in coredump_task_exit() that was added. > > Oh, that makes sense. > > Well, it makes sense for the bug, but that whole > > preempt_disable(); > current->flags &= ~PF_IO_WORKER; > preempt_enable(); > > thin in io_worker_exit() does *not* make sense to me. > > Does removing those three lines make things "JustWork(tm)"? You snipped the suspicion in my reply on why that exists, to avoid io_wq_worker_sleeping() triggering. But arguably this should be covered by the RUNNING flag. I'll poke at it shortly, and yeah then we should just remove the PF_IO_WORKER clearing. Or maybe I'm just smoking crack and it's no longer needed at all. Will test and send a patch. -- Jens Axboe