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 bombadil.infradead.org (bombadil.infradead.org [198.137.202.133]) (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 49844C54E5D for ; Wed, 13 Mar 2024 00:49:11 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; q=dns/txt; c=relaxed/relaxed; d=lists.infradead.org; s=bombadil.20210309; h=Sender: Content-Transfer-Encoding:Content-Type:List-Subscribe:List-Help:List-Post: List-Archive:List-Unsubscribe:List-Id:In-Reply-To:MIME-Version:References: Message-ID:Subject:Cc:To:From:Date:Reply-To:Content-ID:Content-Description: Resent-Date:Resent-From:Resent-Sender:Resent-To:Resent-Cc:Resent-Message-ID: List-Owner; bh=9sMkh4fVmT+EdKg28RGK1gZx2eG4HF4UwEFSVr+AGxM=; b=LI/MnDCe/Jw+Xy qM/l/ET1Afjihbrl9dT8ZOoAQgCWzE6k+UEYcXOSrlLaKK9cL7ouWQo4PuMw843PHh3M15nvKTQpZ YyR457TUUsAJqe36q5RqQyU7rPDg0JiulC9tYT4j4+jyxbzQktLhvLJIG1IIqkiagB9yk7fphEq3I nLMhp6YUz0kIL6RJID+3LMMNdi5pgDXS4Lv0AEIZAflx/2gfwtxvriRJfhF3Ot8MqEB2gotrfW/ve vFarAls1NWGqifKu16megkdBAW/MPkslA/rGVKtklFLG5RXzXAfhsL0ea9M5i3/RAmikn779itjDk P5vEo4Fb1bmpRVWGRMcQ==; Received: from localhost ([::1] helo=bombadil.infradead.org) by bombadil.infradead.org with esmtp (Exim 4.97.1 #2 (Red Hat Linux)) id 1rkCni-00000008B1M-3Av4; Wed, 13 Mar 2024 00:48:58 +0000 Received: from us-smtp-delivery-124.mimecast.com ([170.10.133.124]) by bombadil.infradead.org with esmtps (Exim 4.97.1 #2 (Red Hat Linux)) id 1rkCne-00000008AzN-0alU for linux-arm-kernel@lists.infradead.org; Wed, 13 Mar 2024 00:48:56 +0000 DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=redhat.com; s=mimecast20190719; t=1710290931; 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=V/I7rfb7fSwv9EVlLwLZyE6cq/I2crR3JWNIky7ODFU=; b=PC9BYsAsDLiDvs1nBmqlFUuek5Fy0A7qVJJZu8I1qKIC9usQxxk2X4YUDT6fLgXXsvYH9U e/rdNtC0qocAtEIFCXxde79tN+yKq61dlWbrpxUzUVS2mE4mWZS+epGuY6gHyAsEJU3CmJ JfvHvMEcxsU4WzNgRO6en9CBEFi5f6Y= Received: from mimecast-mx02.redhat.com (mimecast-mx02.redhat.com [66.187.233.88]) by relay.mimecast.com with ESMTP with STARTTLS (version=TLSv1.3, cipher=TLS_AES_256_GCM_SHA384) id us-mta-182-Tx39TiVcPDK1NGuCqWNU_g-1; Tue, 12 Mar 2024 20:48:48 -0400 X-MC-Unique: Tx39TiVcPDK1NGuCqWNU_g-1 Received: from smtp.corp.redhat.com (int-mx05.intmail.prod.int.rdu2.redhat.com [10.11.54.5]) (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 mimecast-mx02.redhat.com (Postfix) with ESMTPS id CAF58800262; Wed, 13 Mar 2024 00:48:47 +0000 (UTC) Received: from localhost (unknown [10.72.116.13]) by smtp.corp.redhat.com (Postfix) with ESMTPS id 24F7510E47; Wed, 13 Mar 2024 00:48:46 +0000 (UTC) Date: Wed, 13 Mar 2024 08:48:44 +0800 From: Baoquan He To: Jiri Slaby Cc: linux-kernel@vger.kernel.org, kexec@lists.infradead.org, x86@kernel.org, linux-arm-kernel@lists.infradead.org, linux-riscv@lists.infradead.org, linuxppc-dev@lists.ozlabs.org, linux-parisc@vger.kernel.org, akpm@linux-foundation.org, joe@perches.com, nathan@kernel.org, conor@kernel.org Subject: Re: kexec verbose dumps with 6.8 [was: [PATCH v4 1/7] kexec_file: add kexec_file flag to control debug printing] Message-ID: References: <20231213055747.61826-1-bhe@redhat.com> <20231213055747.61826-2-bhe@redhat.com> <4c775fca-5def-4a2d-8437-7130b02722a2@kernel.org> MIME-Version: 1.0 Content-Disposition: inline In-Reply-To: <4c775fca-5def-4a2d-8437-7130b02722a2@kernel.org> X-Scanned-By: MIMEDefang 3.4.1 on 10.11.54.5 X-CRM114-Version: 20100106-BlameMichelson ( TRE 0.8.0 (BSD) ) MR-646709E3 X-CRM114-CacheID: sfid-20240312_174854_270557_C9D6435D X-CRM114-Status: GOOD ( 21.67 ) X-BeenThere: linux-arm-kernel@lists.infradead.org X-Mailman-Version: 2.1.34 Precedence: list List-Id: List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Content-Type: text/plain; charset="us-ascii" Content-Transfer-Encoding: 7bit Sender: "linux-arm-kernel" Errors-To: linux-arm-kernel-bounces+linux-arm-kernel=archiver.kernel.org@lists.infradead.org Hi Jiri, On 03/12/24 at 10:58am, Jiri Slaby wrote: > On 13. 12. 23, 6:57, Baoquan He wrote: ... snip... > > --- a/include/linux/kexec.h > > +++ b/include/linux/kexec.h > ... > > @@ -500,6 +500,13 @@ static inline int crash_hotplug_memory_support(void) { return 0; } > > static inline unsigned int crash_get_elfcorehdr_size(void) { return 0; } > > #endif > > +extern bool kexec_file_dbg_print; > > + > > +#define kexec_dprintk(fmt, ...) \ > > + printk("%s" fmt, \ > > + kexec_file_dbg_print ? KERN_INFO : KERN_DEBUG, \ > > + ##__VA_ARGS__) > > This means you dump it _always_. Only with different levels. It dumped always too with pr_debug() before, I just add a switch to control it's pr_info() or pr_debug(). > > And without any prefix whatsoever, so people see bloat like this in their > log now: > [ +0.000001] 0000000000001000-000000000009ffff (1) > [ +0.000002] 000000007f96d000-000000007f97efff (3) > [ +0.000002] 0000000000800000-0000000000807fff (4) > [ +0.000001] 000000000080b000-000000000080bfff (4) > [ +0.000002] 0000000000810000-00000000008fffff (4) > [ +0.000001] 000000007f97f000-000000007f9fefff (4) > [ +0.000001] 000000007ff00000-000000007fffffff (4) > [ +0.000002] 0000000000000000-0000000000000fff (2) On which arch are you seeing this? There should be one line above these range printing to tell what they are, like: E820 memmap: 0000000000000000-000000000009a3ff (1) 000000000009a400-000000000009ffff (2) 00000000000e0000-00000000000fffff (2) 0000000000100000-000000006ff83fff (1) 000000006ff84000-000000007ac50fff (2) > > without actually knowing what that is. > > There should be nothing logged if that is not asked for and especially if > kexec load went fine, right? Right. Before this patch, those pr_debug() were already there. You need enable them to print out like add '#define DEBUG' in *.c file, or enable the dynamic debugging of the file or function. With this patch applied, you only need specify '-d' when you execute kexec command with kexec_file load interface, like: kexec -s -l -d /boot/vmlinuz-xxxx.img --initrd xxx.img --reuse-cmdline For kexec_file load, it is not logging if not specifying '-d', unless you take way to make pr_debug() work in that file. > > Can this be redesigned, please? Sure, after making clear what's going on with this, I will try. > > Actually what was wrong on the pr_debug()s? Can you simply turn them on from > the kernel when -d is passed to kexec instead of all this? Joe suggested this during v1 reviewing: https://lore.kernel.org/all/1e7863ec4e4ab10b84fd0e64f30f8464d2e484a3.camel@perches.com/T/#u > > ... > > --- a/kernel/kexec_core.c > > +++ b/kernel/kexec_core.c > > @@ -52,6 +52,8 @@ atomic_t __kexec_lock = ATOMIC_INIT(0); > > /* Flag to indicate we are going to kexec a new kernel */ > > bool kexec_in_progress = false; > > +bool kexec_file_dbg_print; > > Ugh, and a global flag for this? Yeah, kexec_file_dbg_print records if '-d' is specified when 'kexec' command executed. Anything wrong with the global flag? Thanks Baoquan _______________________________________________ linux-arm-kernel mailing list linux-arm-kernel@lists.infradead.org http://lists.infradead.org/mailman/listinfo/linux-arm-kernel