Re: [PATCH] svm: Add mutex_lock to protect apic_access_page_done on AMD systems

From: joro@xxxxxxxxxx
Date: Mon Nov 12 2018 - 08:37:37 EST


On Mon, Nov 12, 2018 at 12:23:14PM +0000, Suthikulpanit, Suravee wrote:
> From: Wei Wang <wawei@xxxxxxxxx>
>
> There is a race condition when accessing kvm->arch.apic_access_page_done.
> Due to it, x86_set_memory_region will fail when creating the second vcpu
> for a svm guest.
>
> Add a mutex_lock to serialize the accesses to apic_access_page_done.
> This lock is also used by vmx for the same purpose.
>
> Signed-off-by: Wei Wang <wawei@xxxxxxxxx>
> Signed-off-by: Amadeusz Juskowiak <ajusk@xxxxxxxxx>
> Signed-off-by: Julian Stecklina <jsteckli@xxxxxxxxx>
> Signed-off-by: Suravee Suthikulpanit <suravee.suthikulpanit@xxxxxxx>

Reviewed-by: Joerg Roedel <jroedel@xxxxxxx>