From: "Luck, Tony" <tony.luck@intel.com>
To: Borislav Petkov <bp@alien8.de>
Cc: Sebastian Andrzej Siewior <bigeasy@linutronix.de>,
linux-kernel@vger.kernel.org, rt@linutronix.de,
linux-edac@vger.kernel.org, x86@kernel.org,
Thomas Gleixner <tglx@linutronix.de>
Subject: Re: [PATCH 22/25] x86/mcheck: Do the init in one place
Date: Mon, 7 Nov 2016 10:55:24 -0800 [thread overview]
Message-ID: <20161107185524.GA2536@intel.com> (raw)
In-Reply-To: <20161107184532.xj6wzdjlzwhshcmf@pd.tnic>
On Mon, Nov 07, 2016 at 07:45:32PM +0100, Borislav Petkov wrote:
> On Thu, Nov 03, 2016 at 03:50:18PM +0100, Sebastian Andrzej Siewior wrote:
> > Part of the init (memory allocation and so on) is done
> > in mcheck_cpu_init(). While moving the the allocation to
> > mcheck_init_device() (where the hotplug calls are initialized) it
> > becomes necessary to move the callback (mcheck_cpu_init()), too.
> >
> > The callback is now removed from identify_cpu() and registered as a
> > hotplug event which is invoked as the very first one which is shortly
> > after the original point of invocation (look at smp_store_cpu_info() and
> > notify_cpu_starting() in smp_callin()).
> > One "visible" difference is that MCE for the boot CPU is not enabled at
> > identify_boot_cpu() time but at device_initcall_sync() time. Either way,
> > both times we had no userland around.
>
> Uh, hm, I'm not sure about this: so the issue I see with this is that
> the more we're delaying the enabling or MCE reporting - and especially
> setting CR4[MCE] - the more we're increasing the window where a MCE
> during early boot will cause a shutdown. (This is what happens if
> CR4[MCE]=0b).
>
> Perhaps we should split the init into a very early init which doesn't
> need to be part of hotplug and the rest, which can do mce_disable_cpu()
> and mce_reenable_cpu().
>
> Tony, how do you see this?
I don't think that helps as much as you'd like it to help (at
least on Intel). A broadcast machine check that finds the boot
CPU has set CR4[MCE]=1 is still going to end up in reset if any
other CPU still has CR4[MCE]=0
-Tony
next prev parent reply other threads:[~2016-11-07 18:55 UTC|newest]
Thread overview: 99+ messages / expand[flat|nested] mbox.gz Atom feed top
2016-11-03 14:49 cpu hotplug: convert more drivers (batch #4) Sebastian Andrzej Siewior
2016-11-03 14:49 ` [PATCH 01/25] fs/buffer: Convert to hotplug state machine Sebastian Andrzej Siewior
2016-11-09 22:52 ` [tip:smp/hotplug] " tip-bot for Sebastian Andrzej Siewior
2016-11-10 16:24 ` [PATCH 01/25] " Al Viro
2016-11-10 16:31 ` Thomas Gleixner
2016-11-03 14:49 ` [PATCH 02/25] kernel/printk: " Sebastian Andrzej Siewior
2016-11-09 22:52 ` [tip:smp/hotplug] " tip-bot for Sebastian Andrzej Siewior
2016-11-03 14:49 ` [PATCH 03/25] mm/memcg: " Sebastian Andrzej Siewior
2016-11-09 22:53 ` [tip:smp/hotplug] " tip-bot for Sebastian Andrzej Siewior
2016-11-03 14:50 ` [PATCH 04/25] lib/percpu_counter: " Sebastian Andrzej Siewior
2016-11-09 22:53 ` [tip:smp/hotplug] " tip-bot for Sebastian Andrzej Siewior
2016-11-03 14:50 ` [PATCH 05/25] lib/radix-tree: " Sebastian Andrzej Siewior
2016-11-09 22:54 ` [tip:smp/hotplug] " tip-bot for Sebastian Andrzej Siewior
2016-11-03 14:50 ` [PATCH 06/25] mm/page_alloc: " Sebastian Andrzej Siewior
2016-11-09 22:54 ` [tip:smp/hotplug] " tip-bot for Sebastian Andrzej Siewior
2016-11-03 14:50 ` [PATCH 07/25] mm/vmscan: " Sebastian Andrzej Siewior
2016-11-09 22:55 ` [tip:smp/hotplug] " tip-bot for Sebastian Andrzej Siewior
2016-11-03 14:50 ` [PATCH 08/25] net/dev: " Sebastian Andrzej Siewior
2016-11-09 22:55 ` [tip:smp/hotplug] " tip-bot for Sebastian Andrzej Siewior
2016-11-03 14:50 ` [PATCH 09/25] net/flowcache: " Sebastian Andrzej Siewior
2016-11-09 22:56 ` [tip:smp/hotplug] " tip-bot for Sebastian Andrzej Siewior
2016-11-03 14:50 ` [PATCH 10/25] s390/smp: Make cpu notifier symetric Sebastian Andrzej Siewior
2016-11-04 14:22 ` Heiko Carstens
2016-11-04 14:41 ` [PATCH 10/25 v2] " Sebastian Andrzej Siewior
2016-11-09 22:56 ` [tip:smp/hotplug] " tip-bot for Thomas Gleixner
2016-11-03 14:50 ` [PATCH 11/25] s390/smp: Convert to hotplug state machine Sebastian Andrzej Siewior
2016-11-04 14:34 ` Heiko Carstens
2016-11-04 14:45 ` [PATCH 11/25 v2] " Sebastian Andrzej Siewior
2016-11-09 22:57 ` [tip:smp/hotplug] " tip-bot for Sebastian Andrzej Siewior
2016-11-03 14:50 ` [PATCH 12/25] drivers base/cacheinfo: " Sebastian Andrzej Siewior
2016-11-09 22:57 ` [tip:smp/hotplug] " tip-bot for Sebastian Andrzej Siewior
2016-11-03 14:50 ` [PATCH 13/25] drivers base/topology: " Sebastian Andrzej Siewior
2016-11-09 22:57 ` [tip:smp/hotplug] " tip-bot for Sebastian Andrzej Siewior
2016-11-03 14:50 ` [PATCH 14/25] ia64/err-inject: " Sebastian Andrzej Siewior
2016-11-09 22:58 ` [tip:smp/hotplug] " tip-bot for Sebastian Andrzej Siewior
2016-11-03 14:50 ` [PATCH 15/25] ia64/palinfo: " Sebastian Andrzej Siewior
2016-11-09 22:58 ` [tip:smp/hotplug] " tip-bot for Sebastian Andrzej Siewior
2016-11-03 14:50 ` [PATCH 16/25] ia64/salinfo: " Sebastian Andrzej Siewior
2016-11-03 15:45 ` kbuild test robot
2016-11-03 17:31 ` [PATCH 16/25 v2] " Sebastian Andrzej Siewior
2016-11-09 22:59 ` [tip:smp/hotplug] " tip-bot for Sebastian Andrzej Siewior
2016-11-03 16:22 ` [PATCH 16/25] " kbuild test robot
2016-11-03 14:50 ` [PATCH 17/25] ia64/topology: " Sebastian Andrzej Siewior
2016-11-03 15:53 ` kbuild test robot
2016-11-03 17:33 ` [PATCH 17/25 v2] " Sebastian Andrzej Siewior
2016-11-09 22:59 ` [tip:smp/hotplug] " tip-bot for Sebastian Andrzej Siewior
2016-11-03 14:50 ` [PATCH 18/25] x86/mcheck: Move threshold_create_device() Sebastian Andrzej Siewior
2016-11-07 10:32 ` Borislav Petkov
2016-11-03 14:50 ` [PATCH 19/25] x86/mcheck: Explicit cleanup on failure in mce_amd Sebastian Andrzej Siewior
2016-11-03 14:50 ` [PATCH 20/25] x86/mcheck: Be prepared for a rollback back to the ONLINE state Sebastian Andrzej Siewior
2016-11-07 10:32 ` Borislav Petkov
2016-11-07 10:40 ` Sebastian Andrzej Siewior
2016-11-07 12:31 ` Borislav Petkov
2016-11-07 17:23 ` Sebastian Andrzej Siewior
2016-11-03 14:50 ` [PATCH 21/25] x86/mcheck: Split threshold_cpu_callback into two callbacks Sebastian Andrzej Siewior
2016-11-07 13:20 ` Borislav Petkov
2016-11-07 13:25 ` Sebastian Andrzej Siewior
2016-11-07 15:07 ` Borislav Petkov
2016-11-07 15:14 ` Sebastian Andrzej Siewior
2016-11-07 17:26 ` Sebastian Andrzej Siewior
2016-11-07 18:19 ` Borislav Petkov
2016-11-03 14:50 ` [PATCH 22/25] x86/mcheck: Do the init in one place Sebastian Andrzej Siewior
2016-11-07 18:45 ` Borislav Petkov
2016-11-07 18:55 ` Luck, Tony [this message]
2016-11-07 20:12 ` Borislav Petkov
2016-11-08 9:23 ` Borislav Petkov
2016-11-09 14:22 ` Sebastian Andrzej Siewior
2016-11-09 15:38 ` Borislav Petkov
2016-11-09 16:24 ` Sebastian Andrzej Siewior
2016-11-09 17:01 ` Borislav Petkov
2016-11-09 17:22 ` Sebastian Andrzej Siewior
2016-11-09 18:37 ` Luck, Tony
2016-11-10 9:00 ` Sebastian Andrzej Siewior
2016-11-10 9:18 ` Borislav Petkov
2016-11-10 17:44 ` x86/mcheck: convert to hotplug state engine, take #2 Sebastian Andrzej Siewior
2016-11-10 17:44 ` [PATCH 1/7] x86/mcheck: Move threshold_create_device() Sebastian Andrzej Siewior
2016-11-16 8:39 ` [tip:smp/hotplug] " tip-bot for Sebastian Andrzej Siewior
2016-11-10 17:44 ` [PATCH 2/7] x86/mcheck: Explicit cleanup on failure in mce_amd Sebastian Andrzej Siewior
2016-11-16 8:40 ` [tip:smp/hotplug] " tip-bot for Sebastian Andrzej Siewior
2016-11-10 17:44 ` [PATCH 3/7] x86/mcheck: Be prepared for a rollback back to the ONLINE state Sebastian Andrzej Siewior
2016-11-16 8:40 ` [tip:smp/hotplug] " tip-bot for Sebastian Andrzej Siewior
2016-11-10 17:44 ` [PATCH 4/7] x86/mcheck: Split threshold_cpu_callback into two callbacks Sebastian Andrzej Siewior
2016-11-16 8:41 ` [tip:smp/hotplug] " tip-bot for Sebastian Andrzej Siewior
2016-11-10 17:44 ` [PATCH 5/7] x86/mcheck: reorganize the hotplug callbacks Sebastian Andrzej Siewior
2016-11-11 18:44 ` Borislav Petkov
2016-11-11 19:36 ` Sebastian Andrzej Siewior
2016-11-11 19:57 ` Borislav Petkov
2016-11-14 10:47 ` [PATCH 5/7 v2] " Sebastian Andrzej Siewior
2016-11-16 8:41 ` [tip:smp/hotplug] x86/mcheck: Reorganize " tip-bot for Sebastian Andrzej Siewior
2016-11-10 17:44 ` [PATCH 6/7] x86/mcheck: Move CPU_ONLINE and CPU_DOWN_PREPARE to hotplug state machine Sebastian Andrzej Siewior
2016-11-16 8:42 ` [tip:smp/hotplug] " tip-bot for Sebastian Andrzej Siewior
2016-11-10 17:44 ` [PATCH 7/7] x86/mcheck: Move CPU_DEAD " Sebastian Andrzej Siewior
2016-11-11 20:18 ` Borislav Petkov
2016-11-16 8:42 ` [tip:smp/hotplug] " tip-bot for Sebastian Andrzej Siewior
2016-11-10 10:22 ` [PATCH 22/25] x86/mcheck: Do the init in one place Thomas Gleixner
2016-11-10 10:27 ` Sebastian Andrzej Siewior
2016-11-03 14:50 ` [PATCH 23/25] x86/mcheck: Make CPU_DOWN_PREPARE the counter part of CPU_STARTING Sebastian Andrzej Siewior
2016-11-03 14:50 ` [PATCH 24/25] x86/mcheck: Move CPU_ONLINE to hotplug state machine Sebastian Andrzej Siewior
2016-11-03 14:50 ` [PATCH 25/25] x86/mcheck: Move CPU_DEAD " Sebastian Andrzej Siewior
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