Re: [PATCH 1/2] KVM: X86: Fix setup the virt_spin_lock_key before static key get initialized

[Davidlohr Bueso <dave@stgolabs.net>]

On Mon, 26 Mar 2018, Wanpeng Li wrote:

>I didn't see any issue when testing this patch, could you elaborate
>what's the bulky mechanism and how it conflicts with early smp bootup
>stages? In addition, do you mean the xen fix is also not suitable?

I have nothing against your patch (or the xen one for that matter), other than
the fact that both seem like band-aid solutions to being able to move up the jump
label init call. I was actually peddling a similar patch but didn't want to add
the extra callback just for that -- at least xen already had smp_ops.smp_prepare_cpus.

Instead of dropping the patches in -tip (ie: delaying the feature), I have nothing
against these fixes being merged. If a better solution is available later, we can
always move dealing with virt_spin_lock_key back into smp_prepare_boot_cpu().

Also a bit unrelated, but am I correct to assume that KVM_HINTS_DEDICATED can be
used via qemu? I've only been dealing with kernel parameters.

Thanks,
Davidlohr