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=-12.5 required=3.0 tests=BAYES_00,DKIMWL_WL_HIGH, DKIM_SIGNED,DKIM_VALID,DKIM_VALID_AU,HEADER_FROM_DIFFERENT_DOMAINS, INCLUDES_PATCH,MAILING_LIST_MULTI,SPF_HELO_NONE,SPF_PASS,USER_AGENT_SANE_1 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 EDF1DC433E9 for ; Fri, 12 Mar 2021 16:24:28 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id C6F656501E for ; Fri, 12 Mar 2021 16:24:28 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S232626AbhCLQX7 (ORCPT ); Fri, 12 Mar 2021 11:23:59 -0500 Received: from us-smtp-delivery-124.mimecast.com ([216.205.24.124]:42532 "EHLO us-smtp-delivery-124.mimecast.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S232233AbhCLQXz (ORCPT ); Fri, 12 Mar 2021 11:23:55 -0500 DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=redhat.com; s=mimecast20190719; t=1615566235; h=from:from:reply-to:subject:subject:date:date:message-id:message-id: to:to:cc:cc:mime-version:mime-version:content-type:content-type: in-reply-to:in-reply-to:references:references; bh=xSYDoiB+Sm1xN1cnL2N1sIO4P5NjsZSPzQuHmVBThEs=; b=JybJNWnhvs8DFqhjd8ff1x4oNU3yNB8yCfOlfPTt61edc8TnIxYaEhP5kgJSzEpe3gY05k m4SZ6eDj4W6EvV4WFDR67TA7aW6PxL1Lh8psWVvxWctBlzrtf2n5EPkGNVO5yZkzMsLPAq pzvr/zQ3sVXeTxlGg1bRUpRB7bUl1+Q= Received: from mimecast-mx01.redhat.com (mimecast-mx01.redhat.com [209.132.183.4]) (Using TLS) by relay.mimecast.com with ESMTP id us-mta-235-hXuGadYlOKGq8yyDOb8syA-1; Fri, 12 Mar 2021 11:23:51 -0500 X-MC-Unique: hXuGadYlOKGq8yyDOb8syA-1 Received: from smtp.corp.redhat.com (int-mx04.intmail.prod.int.phx2.redhat.com [10.5.11.14]) (using TLSv1.2 with cipher AECDH-AES256-SHA (256/256 bits)) (No client certificate requested) by mimecast-mx01.redhat.com (Postfix) with ESMTPS id 31488A40C0; Fri, 12 Mar 2021 16:23:49 +0000 (UTC) Received: from dhcp-27-174.brq.redhat.com (unknown [10.40.195.14]) by smtp.corp.redhat.com (Postfix) with SMTP id B02085D9CC; Fri, 12 Mar 2021 16:23:46 +0000 (UTC) Received: by dhcp-27-174.brq.redhat.com (nbSMTP-1.00) for uid 1000 oleg@redhat.com; Fri, 12 Mar 2021 17:23:48 +0100 (CET) Date: Fri, 12 Mar 2021 17:23:45 +0100 From: Oleg Nesterov To: Qianli Zhao Cc: christian@brauner.io, axboe@kernel.dk, ebiederm@xmission.com, tglx@linutronix.de, pcc@google.com, linux-kernel@vger.kernel.org, zhaoqianli@xiaomi.com Subject: Re: [PATCH V2] exit: trigger panic when global init has exited Message-ID: <20210312162344.GB27820@redhat.com> References: <1615519478-178620-1-git-send-email-zhaoqianligood@gmail.com> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <1615519478-178620-1-git-send-email-zhaoqianligood@gmail.com> User-Agent: Mutt/1.5.24 (2015-08-30) X-Scanned-By: MIMEDefang 2.79 on 10.5.11.14 Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On 03/12, Qianli Zhao wrote: > > --- a/kernel/exit.c > +++ b/kernel/exit.c > @@ -767,6 +767,17 @@ void __noreturn do_exit(long code) > validate_creds_for_do_exit(tsk); > > /* > + * If global init has exited, > + * panic immediately to get a useable coredump. > + */ > + if (unlikely(is_global_init(tsk) && > + (thread_group_empty(tsk) || > + (tsk->signal->flags & SIGNAL_GROUP_EXIT)))) { > + panic("Attempted to kill init! exitcode=0x%08x\n", > + tsk->signal->group_exit_code ?: (int)code); See our discussion with Eric, this is not right. https://lore.kernel.org/lkml/20210310173236.GB8973@redhat.com/ Oleg.