Re: [GIT pull] smp/hotplug: Removal of notifiers
From: Borislav Petkov
Date: Mon Dec 26 2016 - 16:00:33 EST
On Mon, Dec 26, 2016 at 07:21:44PM +0100, Thomas Gleixner wrote:
> Is there anything interesting error message before the BUG hits? I'll try
> to reproduce on a AMD box tomorrow.
Hmm, so lemme see if I see it correctly:
threshold_create_bank() does kobject_create_and_add(name, &dev->kobj);
and that dev thing is
struct device *dev = per_cpu(mce_device, cpu);
BUT(!), those mce_device per-CPU things get initialized in
With a CONFIG_HOTPLUG_CPU=n .config that doesn't happen, right?
Oh, and I see what could've changed that:
8c0eeac819c8 ("x86/mcheck: Move CPU_ONLINE and CPU_DOWN_PREPARE to hotplug state machine")
And before that, we did call mce_device_create(cpu) in
mcheck_init_device() which is a device initcall and not dependent on CPU
And frankly, flipping back to the for_each_online_cpu(i) is yucky as
hell but I don't see any other/better solution besides pulling up
mce_device_create() into mcheck_init_device()...
ECO tip #101: Trim your mails when you reply.