[PATCH 5.6 034/254] irqchip/gic-v4.1: Skip absent CPUs while iterating over redistributors
From: Greg Kroah-Hartman
Date: Thu Apr 16 2020 - 10:18:52 EST
From: Marc Zyngier <maz@xxxxxxxxxx>
[ Upstream commit 28d160de5194c68ff534443d2a8b6f1d10d57c58 ]
In a system that is only sparsly populated with CPUs, we can end-up with
redistributors structures that are not initialized. Let's make sure we
don't try and access those when iterating over them (in this case when
checking we have a L2 VPE table).
Fixes: 4e6437f12d6e ("irqchip/gic-v4.1: Ensure L2 vPE table is allocated at RD level")
Signed-off-by: Marc Zyngier <maz@xxxxxxxxxx>
Reviewed-by: Zenghui Yu <yuzenghui@xxxxxxxxxx>
Reviewed-by: Eric Auger <eric.auger@xxxxxxxxxx>
Link: https://lore.kernel.org/r/20200304203330.4967-3-maz@xxxxxxxxxx
Signed-off-by: Sasha Levin <sashal@xxxxxxxxxx>
---
drivers/irqchip/irq-gic-v3-its.c | 4 ++++
1 file changed, 4 insertions(+)
diff --git a/drivers/irqchip/irq-gic-v3-its.c b/drivers/irqchip/irq-gic-v3-its.c
index 83b1186ffcad0..da883a6910284 100644
--- a/drivers/irqchip/irq-gic-v3-its.c
+++ b/drivers/irqchip/irq-gic-v3-its.c
@@ -2452,6 +2452,10 @@ static bool allocate_vpe_l2_table(int cpu, u32 id)
if (!gic_rdists->has_rvpeid)
return true;
+ /* Skip non-present CPUs */
+ if (!base)
+ return true;
+
val = gicr_read_vpropbaser(base + SZ_128K + GICR_VPROPBASER);
esz = FIELD_GET(GICR_VPROPBASER_4_1_ENTRY_SIZE, val) + 1;
--
2.20.1