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 lists.ozlabs.org (lists.ozlabs.org [112.213.38.117]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by smtp.lore.kernel.org (Postfix) with ESMTPS id C4852C5320E for ; Tue, 27 Aug 2024 09:02:23 +0000 (UTC) Received: from boromir.ozlabs.org (localhost [127.0.0.1]) by lists.ozlabs.org (Postfix) with ESMTP id 4WtM4Z1ylsz2yV3; Tue, 27 Aug 2024 19:02:22 +1000 (AEST) Authentication-Results: lists.ozlabs.org; arc=none smtp.remote-ip=170.10.133.124 ARC-Seal: i=1; a=rsa-sha256; d=lists.ozlabs.org; s=201707; t=1724749342; cv=none; b=cP3/zXL4N2v2oZTMJzUiPzDbX4wOseEXm3OI/9HkBLYT9fHbwfcXXzukOF6iqRKsOiVdStsQsw/GqwYmzvvGny6EXPASQLeHyKn4MLGy1KwsKXuZjSkCn/5s4bKzfQqqdg+TI+Ldlv+R/xEcEIarLmOx1gs8nGqrfFh2h7eXEBX8lXfh3iBhzibp+FLAk7Jq56NasKSWZSVbZ5ufDvSzj29xVKhhPu5gQqRAvkquNlomiEFB/KW05iivKBQH4/4BlYzQJLVflY0uUpQ0Pta16Mthmso+edh9LZfiuML8DxCjdZ0+1T2c6vOEx+durpusUCCQ8aIYZhkORgJukYzYtw== ARC-Message-Signature: i=1; a=rsa-sha256; d=lists.ozlabs.org; s=201707; t=1724749342; c=relaxed/relaxed; bh=outpxqXc6KM2Oo4/0nqD4smTGWGwDj3DOJrNewpgErA=; h=DKIM-Signature:DKIM-Signature:Received:X-MC-Unique:Received: Received:Date:From:To:Cc:Subject:Message-ID:References: MIME-Version:Content-Type:Content-Disposition:In-Reply-To: X-Scanned-By; b=cd8Et8x0i4ER1uvte5S04hWACDi9dhjza4V9vo7NQTb9+K/4k1wLwSYyuj9w4hwN/pz5+XGKpfHPDtAYwQJ5uxLUynS5e/nZEQmQD35jf9A2NpBRrdAWx2ObVEpQt1wA/AaOYhEWvivdemwDtqLFBOS2DxzouG5iQQjfP30yjGYJxc9wEgPA39RsfXcZj+4xgVnzGdKKhyUnbry9NMMlOhl68ZhXKRxgmNfTts+C50VcVyXCaI9dni+xHtG0Hr5aRRoM+b5d09p04oI3G45sgCFRsxRHdwCVPVn9VfqeVCewxNR2lHSBaOQV9A4xK/IvA+tMwXKhF3zzN647NV9dwA== ARC-Authentication-Results: i=1; lists.ozlabs.org; dmarc=pass (p=none dis=none) header.from=redhat.com; dkim=pass (1024-bit key; unprotected) header.d=redhat.com header.i=@redhat.com header.a=rsa-sha256 header.s=mimecast20190719 header.b=N1Wkvdzz; dkim=pass (1024-bit key) header.d=redhat.com header.i=@redhat.com header.a=rsa-sha256 header.s=mimecast20190719 header.b=WLtO8reA; dkim-atps=neutral; spf=pass (client-ip=170.10.133.124; helo=us-smtp-delivery-124.mimecast.com; envelope-from=bhe@redhat.com; receiver=lists.ozlabs.org) smtp.mailfrom=redhat.com Authentication-Results: lists.ozlabs.org; dmarc=pass (p=none dis=none) header.from=redhat.com Authentication-Results: lists.ozlabs.org; dkim=pass (1024-bit key; unprotected) header.d=redhat.com header.i=@redhat.com header.a=rsa-sha256 header.s=mimecast20190719 header.b=N1Wkvdzz; dkim=pass (1024-bit key) header.d=redhat.com header.i=@redhat.com header.a=rsa-sha256 header.s=mimecast20190719 header.b=WLtO8reA; dkim-atps=neutral Authentication-Results: lists.ozlabs.org; spf=pass (sender SPF authorized) smtp.mailfrom=redhat.com (client-ip=170.10.133.124; helo=us-smtp-delivery-124.mimecast.com; envelope-from=bhe@redhat.com; receiver=lists.ozlabs.org) Received: from us-smtp-delivery-124.mimecast.com (us-smtp-delivery-124.mimecast.com [170.10.133.124]) (using TLSv1.3 with cipher TLS_AES_256_GCM_SHA384 (256/256 bits) key-exchange X25519 server-signature RSA-PSS (2048 bits) server-digest SHA256) (No client certificate requested) by lists.ozlabs.org (Postfix) with ESMTPS id 4WtM4Y5QsRz2yTy for ; Tue, 27 Aug 2024 19:02:17 +1000 (AEST) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=redhat.com; s=mimecast20190719; t=1724749333; 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=outpxqXc6KM2Oo4/0nqD4smTGWGwDj3DOJrNewpgErA=; b=N1WkvdzzDZOd8IDkWCvREPDSBaLOj59fzHV5vSPtoY9WDifl8tFHdmq8DDRnqE0d+khI1Z NWXAwpTCTMgtGgKf3CrkTjIMFYT/rqfGYhDgTi5Qt4/0P5s29TBJPvVvq2HuRgD/EhrJcp 8/owWw3xyzI5VwFEpwRSzCikIwTAVno= DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=redhat.com; s=mimecast20190719; t=1724749334; 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=outpxqXc6KM2Oo4/0nqD4smTGWGwDj3DOJrNewpgErA=; b=WLtO8reAD9dI6vjKb8G/CJYbIty+JwlRynkohZgoD1AjZV89wKlPryQLXYN+U+uhvelRFr a1f8rICZ3pVBHr4WMqiTlbZrL2yazim1i3dp1jziUOUaJ5Ie3eB3zf0D80oFW63oNbJF7K +qiOzlqkVnGh0ay8CDtr3wWtJV50fzk= Received: from mx-prod-mc-01.mail-002.prod.us-west-2.aws.redhat.com (ec2-54-186-198-63.us-west-2.compute.amazonaws.com [54.186.198.63]) by relay.mimecast.com with ESMTP with STARTTLS (version=TLSv1.3, cipher=TLS_AES_256_GCM_SHA384) id us-mta-468-rv4ABExJM5egEclpNPuyLA-1; Tue, 27 Aug 2024 05:02:08 -0400 X-MC-Unique: rv4ABExJM5egEclpNPuyLA-1 Received: from mx-prod-int-02.mail-002.prod.us-west-2.aws.redhat.com (mx-prod-int-02.mail-002.prod.us-west-2.aws.redhat.com [10.30.177.15]) (using TLSv1.3 with cipher TLS_AES_256_GCM_SHA384 (256/256 bits) key-exchange X25519 server-signature RSA-PSS (2048 bits) server-digest SHA256) (No client certificate requested) by mx-prod-mc-01.mail-002.prod.us-west-2.aws.redhat.com (Postfix) with ESMTPS id 7B6471955BFE; Tue, 27 Aug 2024 09:02:05 +0000 (UTC) Received: from localhost (unknown [10.72.112.42]) by mx-prod-int-02.mail-002.prod.us-west-2.aws.redhat.com (Postfix) with ESMTPS id 416C019560AA; Tue, 27 Aug 2024 09:02:02 +0000 (UTC) Date: Tue, 27 Aug 2024 17:01:58 +0800 From: Baoquan He To: John Paul Adrian Glaubitz Cc: Geert Uytterhoeven , Dave Vasilevsky , linuxppc-dev@lists.ozlabs.org, linux-sh@vger.kernel.org, mpe@ellerman.id.au, kexec@lists.infradead.org, linux-kernel@vger.kernel.org, Reimar =?iso-8859-1?Q?D=F6ffinger?= Subject: Re: [PATCH] crash: Default to CRASH_DUMP=n when support for it is unlikely Message-ID: References: <20240823125156.104775-1-dave@vasilevsky.ca> <09c29a3c4879d4ce5d8b97fd60d8ba5e38bed979.camel@physik.fu-berlin.de> X-Mailing-List: linuxppc-dev@lists.ozlabs.org List-Id: List-Help: List-Post: List-Subscribe: , , List-Unsubscribe: MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: X-Scanned-By: MIMEDefang 3.0 on 10.30.177.15 On 08/27/24 at 08:37am, John Paul Adrian Glaubitz wrote: > On Tue, 2024-08-27 at 14:22 +0800, Baoquan He wrote: > > About why it's enabled by default, as Michael has explained in another > > thread, distros usualy needs to enable it by default because vmcore > > dumping is a very important feature on servers, even guest instances. > > Even though kdump codes are enabled to built in, not providing > > crashkernel= value won't make vmcore dumping take effect, it won't cost > > system resources in that case. > > OK, thanks for the explanation. But as we have found out in the mean time, > the assumption was wrong to enable it by default for all architectures as > some architectures cannot boot a crash dump kernel with their default bootloader > but only through kexec. > > Can we have a follow-up patch to disable crash dump kernels where they're > not needed? I mean, not every platform supported by Linux is obviously a > x86-based or POWER-based server. Yes, while isn't Dave's patch a good one to fix it? In Dave's patch, the default enabling of CRASH_DUMP has been taken off, change to rely on ARCH_DEFAULT_CRASH_DUMP provided by each arch. config CRASH_DUMP bool "kernel crash dumps" - default y + default ARCH_DEFAULT_CRASH_DUMP