Re: [Xen-devel] [PATCH] xen/pvhsim: fix cpu onlining

[Jürgen Groß <jgross@xxxxxxxx>]

On 23.10.19 14:55, Roger Pau Monné wrote:
> On Wed, Oct 23, 2019 at 02:12:09PM +0200, Juergen Gross wrote:
> > Since commit 8d3c326f6756d1 ("xen: let vcpu_create() select processor")
> > the initial processor for all pv-shim vcpus will be 0, as no other cpus
> > are online when the vcpus are created. Before that commit the vcpus
> > would have processors set not being online yet, which worked just by
> > chance.
> >
> > When the pv-shim vcpu becomes active it will have a hard affinity
> > not matching its initial processor assignment leading to failing
> > ASSERT()s or other problems depending on the selected scheduler.
> >
> > Fix that by doing the affinity setting after onlining the cpu but
> > before taking the vcpu up. For vcpu 0 this is still in
> > sched_setup_dom0_vcpus(), for the other vcpus setting the affinity
> > there can be dropped.
> >
> > Fixes: 8d3c326f6756d1 ("xen: let vcpu_create() select processor")
> > Reported-by: Sergey Dyasli <sergey.dyasli@xxxxxxxxxx>
> > Tested-by: Sergey Dyasli <sergey.dyasli@xxxxxxxxxx>
> > Signed-off-by: Juergen Gross <jgross@xxxxxxxx>
> Reviewed-by: Roger Pau Monné <roger.pau@xxxxxxxxxx>
And just for the protocol:

Release-acked-by: Juergen Gross <jgross@xxxxxxxx>


Juergen

_______________________________________________
Xen-devel mailing list
Xen-devel@xxxxxxxxxxxxxxxxxxxx
https://lists.xenproject.org/mailman/listinfo/xen-devel