Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1751964AbaDCLii (ORCPT ); Thu, 3 Apr 2014 07:38:38 -0400 Received: from mail-wg0-f45.google.com ([74.125.82.45]:46938 "EHLO mail-wg0-f45.google.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1751834AbaDCLie (ORCPT ); Thu, 3 Apr 2014 07:38:34 -0400 Date: Thu, 3 Apr 2014 13:38:29 +0200 From: Ingo Molnar To: Borislav Petkov Cc: Linus Torvalds , Jiri Kosina , Andrew Morton , Mateusz Guzik , Greg Kroah-Hartman , Steven Rostedt , LKML , Thomas Gleixner , "H. Peter Anvin" , Mel Gorman , Kay Sievers Subject: Re: [RFC PATCH] cmdline: Hide "debug" from /proc/cmdline Message-ID: <20140403113829.GA715@gmail.com> References: <20140402144219.4cafbe37@gandalf.local.home> <20140402221212.GD16570@mguzik.redhat.com> <20140402162839.d3c00e9845e89d0f092c2ce3@linux-foundation.org> <20140403112313.GE9616@pd.tnic> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <20140403112313.GE9616@pd.tnic> User-Agent: Mutt/1.5.21 (2010-09-15) Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org * Borislav Petkov wrote: > On Wed, Apr 02, 2014 at 06:47:57PM -0700, Linus Torvalds wrote: > > Whether it actually fixes the problem that Borislav had is > > questionable, of course. For all I know, systemd debug mode generates > > so much data in *other* ways and then causes feedback loops with > > the kernel debugging that this patch is totally immaterial, and > > dmesg was never the main issue. But unlike the "hide 'debug' from > > /proc/cmdline", I think this patch at least _conceptually_ makes a lot > > of sense, even if systemd gets fixed, so ... > > > > Borislav? > > Yes, ratelimiting makes the box actually boot all the way. Here's how it > looks like: > > ^MLoading Linux 3.12.16-boris-00441-g60dc93e99a75-dirty ... > ^MLoading initial ramdisk ... > ^M[ 0.000000] Initializing cgroup subsys cpuset > [ 0.000000] Initializing cgroup subsys cpu > [ 0.000000] Initializing cgroup subsys cpuacct > [ 0.000000] Linux version 3.12.16-boris-00441-g60dc93e99a75-dirty (gcc version 4.3.4 [gcc-4_3-branch revision 152973] (SUSE Linux) ) #11 SMP Thu Apr 3 10:19:49 CEST 2014 > [ 0.000000] Command line: BOOT_IMAGE=/@/boot/vmlinuz-3.12.16-boris-00441-g60dc93e99a75-dirty root=UUID=5f1a28cf-d910- > 4ed0-85ac-0113d43e553f rootflags=subvol=@ resume=/dev/disk/by-uuid/45671aef-cef3-4fcd-9087-7d4f3f81aa70 splash=off showo > pts crashkernel=256M-:128M pci=hpiosize=0 pci=hpmemsize=4m pciehp.pciehp_force=1 notsc mem=0x40000000000 loop.max_loop=6 > 4 log_buf_len=16M console=tty0 console=ttyS0,38400n8 ignore_loglevel debug > ^^^^^ > > We haz the "debug" thing on. > > ... > > Here we go: > > [ 50.636000] be2net 0000:db:00.0: irq 102 for MSI/MSI-X > [ 50.636000] be2net 0000:db:00.0: irq 103 for MSI/MSI-X > [ 50.636000] be2net 0000:db:00.0: irq 104 for MSI/MSI-X > [ 50.636000] be2net 0000:db:00.0: enabled 4 MSI-x vector(s) for NIC > [ 50.896000] systemd: 1008 callbacks suppressed > ^^^^ > > [ 50.896000] systemd[1]: Started Show Plymouth Boot Screen. > [ 50.896000] systemd[1]: Got SIGCHLD for process 1192 (swapon) > [ 50.896000] systemd[1]: Child 1192 died (code=exited, status=0/SUCCESS) > [ 50.896000] systemd[1]: Child 1192 belongs to dev-disk-by\x2duuid-45671aef\x2dcef3\x2d4fcd\x2d9087\x2d7d4f3f81aa70.swap > [ 50.896000] systemd[1]: dev-disk-by\x2duuid-45671aef\x2dcef3\x2d4fcd\x2d9087\x2d7d4f3f81aa70.swap swap process exited, code=exited status=0 > [ 50.896000] systemd[1]: dev-disk-by\x2duuid-45671aef\x2dcef3\x2d4fcd\x2d9087\x2d7d4f3f81aa70.swap changed activating -> active > [ 50.896000] systemd[1]: Job dev-disk-by\x2duuid-45671aef\x2dcef3\x2d4fcd\x2d9087\x2d7d4f3f81aa70.swap/start finished, result=done > > ... > > [ 57.988000] scsi2 : Emulex 10Gbe open-iscsi Initiator Driver > [ 63.028000] be2iscsi 0000:db:00.3: irq 117 for MSI/MSI-X > [ 63.044000] be2iscsi 0000:db:00.3: irq 118 for MSI/MSI-X > [ 63.064000] be2iscsi 0000:db:00.3: irq 119 for MSI/MSI-X > [ 63.080000] be2iscsi 0000:db:00.3: irq 120 for MSI/MSI-X > [ 63.100000] be2iscsi 0000:db:00.3: irq 121 for MSI/MSI-X > [ 63.116000] be2iscsi 0000:db:00.3: irq 122 for MSI/MSI-X > [ 63.132000] be2iscsi 0000:db:00.3: irq 123 for MSI/MSI-X > [ 63.152000] be2iscsi 0000:db:00.3: irq 124 for MSI/MSI-X > [ 63.572000] scsi host2: BC_373 : Link Down on Port 1 > [ 63.588000] scsi host2: BM_4336 : No boot session > [ 63.656000] systemd: 11828 callbacks suppressed > ^^^^^ > > We luvz to talk a lot of crap, don't we. When I suggested that systemd should reuse the tracing and perf ring buffer infrastructure instead of cluttering the syslog it was handwaved away... But at least there's an upside for me: I don't have to deal with the systemd maintainers' excessively passive-aggressive behavior ;-) Thanks, Ingo -- To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to majordomo@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/