[PATCH] KVM: arm64: vgic-debug: Don't put unmarked LPIs

[Zenghui Yu]

On 2024/8/17 18:25, Marc Zyngier wrote:
> On Sat, 17 Aug 2024 11:15:41 +0100,
> Zenghui Yu <yuzenghui at huawei.com> wrote:
> >
> > If there were LPIs being mapped behind our back (i.e., between .start() and
> > .stop()), we would put them at iter_unmark_lpis() without checking if they
> > were actually *marked*, which is obviously not good.
> >
> > Switch to use the xa_for_each_marked() iterator to fix it.
> >
> > Fixes: 85d3ccc8b75b ("KVM: arm64: vgic-debug: Use an xarray mark for debug iterator")
> > Signed-off-by: Zenghui Yu <yuzenghui at huawei.com>
> > ---
> >  arch/arm64/kvm/vgic/vgic-debug.c | 2 +-
> >  1 file changed, 1 insertion(+), 1 deletion(-)
> >
> > diff --git a/arch/arm64/kvm/vgic/vgic-debug.c b/arch/arm64/kvm/vgic/vgic-debug.c
> > index bc74d06398ef..e1397ab2072a 100644
> > --- a/arch/arm64/kvm/vgic/vgic-debug.c
> > +++ b/arch/arm64/kvm/vgic/vgic-debug.c
> > @@ -85,7 +85,7 @@ static void iter_unmark_lpis(struct kvm *kvm)
> >  	struct vgic_irq *irq;
> >  	unsigned long intid;
> >  
> > -	xa_for_each(&dist->lpi_xa, intid, irq) {
> > +	xa_for_each_marked(&dist->lpi_xa, intid, irq, LPI_XA_MARK_DEBUG_ITER) {
> >  		xa_clear_mark(&dist->lpi_xa, intid, LPI_XA_MARK_DEBUG_ITER);
> >  		vgic_put_irq(kvm, irq);
> >  	}
> 
> Ouch. Nicely caught. I think this deserves a
> 
> Cc: stable at vger.kernel.org # v6.10

Yup. I guess Oliver will help to add it when applying ;-)

> 
> With that,
> 
> Reviewed-by: Marc Zyngier <maz at kernel.org>

Thanks!

Zenghui