[PATCH v2 5/6] ACPI: Remove side effect of partly creating a node in acpi_get_node
Jonathan Cameron
Jonathan.Cameron at huawei.com
Fri Jul 17 13:59:58 EDT 2020
acpi_get_node calls acpi_get_pxm to evaluate the _PXM AML method for
entries found in DSDT/SSDT. ACPI 6.3 sec 6.2.14 states
"_PXM evaluates to an integer that identifies a device as belonging to
a Proximity Domain defined in the System Resource Affinity Table (SRAT)."
Hence a _PXM method should not result in creation of a new NUMA node.
Before this patch, _PXM could result in partial instantiation of
NUMA node, missing elements such as zone lists. A call to devm_kzalloc
for example results in a null pointer dereference.
This patch therefore replaces the acpi_map_pxm_to_node with a call
to pxm_to_node.
Signed-off-by: Jonathan Cameron <Jonathan.Cameron at huawei.com>
---
drivers/acpi/numa/srat.c | 2 +-
1 file changed, 1 insertion(+), 1 deletion(-)
diff --git a/drivers/acpi/numa/srat.c b/drivers/acpi/numa/srat.c
index 8ef44ee0d76b..697a5c9e2eb5 100644
--- a/drivers/acpi/numa/srat.c
+++ b/drivers/acpi/numa/srat.c
@@ -444,6 +444,6 @@ int acpi_get_node(acpi_handle handle)
pxm = acpi_get_pxm(handle);
- return acpi_map_pxm_to_node(pxm);
+ return pxm_to_node(pxm);
}
EXPORT_SYMBOL(acpi_get_node);
--
2.19.1
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