From: Marc Zyngier maz@kernel.org
[ 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@kernel.org Reviewed-by: Zenghui Yu yuzenghui@huawei.com Reviewed-by: Eric Auger eric.auger@redhat.com Link: https://lore.kernel.org/r/20200304203330.4967-3-maz@kernel.org Signed-off-by: Sasha Levin sashal@kernel.org --- 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;