[PATCH v3 1/5] x86/numa: Fix SRAT lookup of CFMWS ranges with numa_fill_memblks()

Robert Richter
2024-04-19T14:02:51Z

For configurations that have the kconfig option NUMA_KEEP_MEMINFO
disabled, the SRAT lookup done with numa_fill_memblks() fails
returning NUMA_NO_MEMBLK (-1). An existing SRAT memory range cannot be
found for a CFMWS address range. This causes the addition of a
duplicate numa_memblk with a different node id and a subsequent page
fault and kernel crash during boot.

numa_fill_memblks() is implemented and used in the init section only.
The option NUMA_KEEP_MEMINFO is only for the case when NUMA data will
be used outside of init. So fix the SRAT lookup by moving
numa_fill_memblks() out of the NUMA_KEEP_MEMINFO block to make it
always available in the init section.

Note that the issue was initially introduced with [1]. But since
phys_to_target_node() was originally used that returned the valid node
0, an additional numa_memblk was not added. Though, the node id was
wrong too.

[1] commit fd49f99c1809 ("ACPI: NUMA: Add a node and memblk for each
CFMWS not in SRAT")

Fixes: 8f1004679987 ("ACPI/NUMA: Apply SRAT proximity domain to entire CFMWS window")
Cc: Derick Marks <derick.w.marks@intel.com>
Cc: Dan Williams <dan.j.williams@intel.com>
Cc: Alison Schofield <alison.schofield@intel.com>
Signed-off-by: Robert Richter <rrichter@amd.com>
---
arch/x86/include/asm/sparsemem.h | 2 +-
arch/x86/mm/numa.c | 4 ++--
2 files changed, 3 insertions(+), 3 deletions(-)

diff --git a/arch/x86/include/asm/sparsemem.h b/arch/x86/include/asm/sparsemem.h
index 1be13b2dfe8b..1aaa447ef24b 100644
--- a/arch/x86/include/asm/sparsemem.h
+++ b/arch/x86/include/asm/sparsemem.h
@@ -37,9 +37,9 @@ extern int phys_to_target_node(phys_addr_t start);
#define phys_to_target_node phys_to_target_node
extern int memory_add_physaddr_to_nid(u64 start);
#define memory_add_physaddr_to_nid memory_add_physaddr_to_nid
+#endif
extern int numa_fill_memblks(u64 start, u64 end);
#define numa_fill_memblks numa_fill_memblks
-#endif
#endif /* __ASSEMBLY__ */

#endif /* _ASM_X86_SPARSEMEM_H */
diff --git a/arch/x86/mm/numa.c b/arch/x86/mm/numa.c
index 65e9a6e391c0..ce84ba86e69e 100644
--- a/arch/x86/mm/numa.c
+++ b/arch/x86/mm/numa.c
@@ -929,6 +929,8 @@ int memory_add_physaddr_to_nid(u64 start)
}
EXPORT_SYMBOL_GPL(memory_add_physaddr_to_nid);

+#endif
+
static int __init cmp_memblk(const void *a, const void *b)
{
const struct numa_memblk *ma = *(const struct numa_memblk **)a;
@@ -1001,5 +1003,3 @@ int __init numa_fill_memblks(u64 start, u64 end)
}
return 0;
}
-
-#endif
--
2.39.2