From: Marc Zyngier maz@kernel.org
[ Upstream commit 926b5dfa6b8dc666ff398044af6906b156e1d949 ]
We currently allocate redistributor region structures for individual redistributors when ACPI doesn't present us with compact MMIO regions covering multiple redistributors.
It turns out that we allocate these structures even when the redistributor is flagged as disabled by ACPI. It works fine until someone actually tries to tarse one of these structures, and access the corresponding MMIO region.
Instead, track the number of enabled redistributors, and only allocate what is required. This makes sure that there is no invalid data to misuse.
Signed-off-by: Marc Zyngier maz@kernel.org Reported-by: Heyi Guo guoheyi@huawei.com Tested-by: Heyi Guo guoheyi@huawei.com Link: https://lore.kernel.org/r/20191216062745.63397-1-guoheyi@huawei.com Signed-off-by: Sasha Levin sashal@kernel.org --- drivers/irqchip/irq-gic-v3.c | 9 +++++++-- 1 file changed, 7 insertions(+), 2 deletions(-)
diff --git a/drivers/irqchip/irq-gic-v3.c b/drivers/irqchip/irq-gic-v3.c index 1edc99335a946..446603efbc90b 100644 --- a/drivers/irqchip/irq-gic-v3.c +++ b/drivers/irqchip/irq-gic-v3.c @@ -1801,6 +1801,7 @@ static struct struct redist_region *redist_regs; u32 nr_redist_regions; bool single_redist; + int enabled_rdists; u32 maint_irq; int maint_irq_mode; phys_addr_t vcpu_base; @@ -1895,8 +1896,10 @@ static int __init gic_acpi_match_gicc(union acpi_subtable_headers *header, * If GICC is enabled and has valid gicr base address, then it means * GICR base is presented via GICC */ - if ((gicc->flags & ACPI_MADT_ENABLED) && gicc->gicr_base_address) + if ((gicc->flags & ACPI_MADT_ENABLED) && gicc->gicr_base_address) { + acpi_data.enabled_rdists++; return 0; + }
/* * It's perfectly valid firmware can pass disabled GICC entry, driver @@ -1926,8 +1929,10 @@ static int __init gic_acpi_count_gicr_regions(void)
count = acpi_table_parse_madt(ACPI_MADT_TYPE_GENERIC_INTERRUPT, gic_acpi_match_gicc, 0); - if (count > 0) + if (count > 0) { acpi_data.single_redist = true; + count = acpi_data.enabled_rdists; + }
return count; }