[PATCH v4 01/12] KVM: arm/arm64: Set dist->spis to NULL after kfree

From: Eric Auger
Date: Fri Apr 27 2018 - 10:15:26 EST

in case kvm_vgic_map_resources() fails, typically if the vgic
distributor is not defined, __kvm_vgic_destroy will be called
several times. Indeed kvm_vgic_map_resources() is called on
first vcpu run. As a result dist->spis is freeed more than once
and on the second time it causes a "kernel BUG at mm/slub.c:3912!"

Set dist->spis to NULL to avoid the crash.

Fixes: ad275b8bb1e6 ("KVM: arm/arm64: vgic-new: vgic_init: implement

Signed-off-by: Eric Auger <eric.auger@xxxxxxxxxx>
Reviewed-by: Marc Zyngier <marc.zyngier@xxxxxxx>
Reviewed-by: Christoffer Dall <christoffer.dall@xxxxxxx>


v2 -> v3:
- added Marc's R-b and Fixed commit
virt/kvm/arm/vgic/vgic-init.c | 1 +
1 file changed, 1 insertion(+)

diff --git a/virt/kvm/arm/vgic/vgic-init.c b/virt/kvm/arm/vgic/vgic-init.c
index 68378fe..c52f03d 100644
--- a/virt/kvm/arm/vgic/vgic-init.c
+++ b/virt/kvm/arm/vgic/vgic-init.c
@@ -308,6 +308,7 @@ static void kvm_vgic_dist_destroy(struct kvm *kvm)
dist->initialized = false;

+ dist->spis = NULL;
dist->nr_spis = 0;

if (vgic_supports_direct_msis(kvm))