From: Eric Auger <eric.auger@redhat.com>
Date: Thu, 26 Oct 2017 17:23:05 +0200
Subject: KVM: arm/arm64: vgic-its: Check CBASER/BASER validity before enabling
the ITS
Patch-mainline: v4.14-rc8
Git-commit: c9b51bb60d944067f36f67750e19c18c3cc2697c
References: bsc#1077761
The spec says it is UNPREDICTABLE to enable the ITS
if any of the following conditions are true:
- GITS_CBASER.Valid == 0.
- GITS_BASER<n>.Valid == 0, for any GITS_BASER<n> register
where the Type field indicates Device.
- GITS_BASER<n>.Valid == 0, for any GITS_BASER<n> register
where the Type field indicates Interrupt Collection and
GITS_TYPER.HCC == 0.
In that case, let's keep the ITS disabled.
Signed-off-by: Eric Auger <eric.auger@redhat.com>
Reported-by: Andre Przywara <andre.przywara@arm.com>
Reviewed-by: Christoffer Dall <christoffer.dall@linaro.org>
Signed-off-by: Christoffer Dall <christoffer.dall@linaro.org>
Acked-by: Alexander Graf <agraf@suse.de>
---
virt/kvm/arm/vgic/vgic-its.c | 11 +++++++++++
1 file changed, 11 insertions(+)
--- a/virt/kvm/arm/vgic/vgic-its.c
+++ b/virt/kvm/arm/vgic/vgic-its.c
@@ -1466,6 +1466,16 @@
{
mutex_lock(&its->cmd_lock);
+ /*
+ * It is UNPREDICTABLE to enable the ITS if any of the CBASER or
+ * device/collection BASER are invalid
+ */
+ if (!its->enabled && (val & GITS_CTLR_ENABLE) &&
+ (!(its->baser_device_table & GITS_BASER_VALID) ||
+ !(its->baser_coll_table & GITS_BASER_VALID) ||
+ !(its->cbaser & GITS_CBASER_VALID)))
+ goto out;
+
its->enabled = !!(val & GITS_CTLR_ENABLE);
/*
@@ -1474,6 +1484,7 @@
*/
vgic_its_process_commands(kvm, its);
+out:
mutex_unlock(&its->cmd_lock);
}