Merge tag 'x86-mm-2023-10-28' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip

Pull x86 mm handling updates from Ingo Molnar:

 - Add new NX-stack self-test

 - Improve NUMA partial-CFMWS handling

 - Fix #VC handler bugs resulting in SEV-SNP boot failures

 - Drop the 4MB memory size restriction on minimal NUMA nodes

 - Reorganize headers a bit, in preparation to header dependency
   reduction efforts

 - Misc cleanups & fixes

* tag 'x86-mm-2023-10-28' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip:
  x86/mm: Drop the 4 MB restriction on minimal NUMA node memory size
  selftests/x86/lam: Zero out buffer for readlink()
  x86/sev: Drop unneeded #include
  x86/sev: Move sev_setup_arch() to mem_encrypt.c
  x86/tdx: Replace deprecated strncpy() with strtomem_pad()
  selftests/x86/mm: Add new test that userspace stack is in fact NX
  x86/sev: Make boot_ghcb_page[] static
  x86/boot: Move x86_cache_alignment initialization to correct spot
  x86/sev-es: Set x86_virt_bits to the correct value straight away, instead of a two-phase approach
  x86/sev-es: Allow copy_from_kernel_nofault() in earlier boot
  x86_64: Show CR4.PSE on auxiliaries like on BSP
  x86/iommu/docs: Update AMD IOMMU specification document URL
  x86/sev/docs: Update document URL in amd-memory-encryption.rst
  x86/mm: Move arch_memory_failure() and arch_is_platform_page() definitions from <asm/processor.h> to <asm/pgtable.h>
  ACPI/NUMA: Apply SRAT proximity domain to entire CFMWS window
  x86/numa: Introduce numa_fill_memblks()

1 files changed, 80 insertions, 7 deletions

diff --git a/arch/x86/mm/numa.c b/arch/x86/mm/numa.c
index c79f12e449ea..4a17f663f949 100644
--- a/arch/x86/mm/numa.c
+++ b/arch/x86/mm/numa.c
@@ -12,6 +12,7 @@
 #include <linux/nodemask.h>
 #include <linux/sched.h>
 #include <linux/topology.h>
+#include <linux/sort.h>
 
 #include <asm/e820/api.h>
 #include <asm/proto.h>
@@ -602,13 +603,6 @@ static int __init numa_register_memblks(struct numa_meminfo *mi)
 		if (start >= end)
 			continue;
 
-		/*
-		 * Don't confuse VM with a node that doesn't have the
-		 * minimum amount of memory:
-		 */
-		if (end && (end - start) < NODE_MIN_SIZE)
-			continue;
-
 		alloc_node_data(nid);
 	}
 
@@ -964,4 +958,83 @@ int memory_add_physaddr_to_nid(u64 start)
 	return nid;
 }
 EXPORT_SYMBOL_GPL(memory_add_physaddr_to_nid);
+
+static int __init cmp_memblk(const void *a, const void *b)
+{
+	const struct numa_memblk *ma = *(const struct numa_memblk **)a;
+	const struct numa_memblk *mb = *(const struct numa_memblk **)b;
+
+	return ma->start - mb->start;
+}
+
+static struct numa_memblk *numa_memblk_list[NR_NODE_MEMBLKS] __initdata;
+
+/**
+ * numa_fill_memblks - Fill gaps in numa_meminfo memblks
+ * @start: address to begin fill
+ * @end: address to end fill
+ *
+ * Find and extend numa_meminfo memblks to cover the @start-@end
+ * physical address range, such that the first memblk includes
+ * @start, the last memblk includes @end, and any gaps in between
+ * are filled.
+ *
+ * RETURNS:
+ * 0		  : Success
+ * NUMA_NO_MEMBLK : No memblk exists in @start-@end range
+ */
+
+int __init numa_fill_memblks(u64 start, u64 end)
+{
+	struct numa_memblk **blk = &numa_memblk_list[0];
+	struct numa_meminfo *mi = &numa_meminfo;
+	int count = 0;
+	u64 prev_end;
+
+	/*
+	 * Create a list of pointers to numa_meminfo memblks that
+	 * overlap start, end. Exclude (start == bi->end) since
+	 * end addresses in both a CFMWS range and a memblk range
+	 * are exclusive.
+	 *
+	 * This list of pointers is used to make in-place changes
+	 * that fill out the numa_meminfo memblks.
+	 */
+	for (int i = 0; i < mi->nr_blks; i++) {
+		struct numa_memblk *bi = &mi->blk[i];
+
+		if (start < bi->end && end >= bi->start) {
+			blk[count] = &mi->blk[i];
+			count++;
+		}
+	}
+	if (!count)
+		return NUMA_NO_MEMBLK;
+
+	/* Sort the list of pointers in memblk->start order */
+	sort(&blk[0], count, sizeof(blk[0]), cmp_memblk, NULL);
+
+	/* Make sure the first/last memblks include start/end */
+	blk[0]->start = min(blk[0]->start, start);
+	blk[count - 1]->end = max(blk[count - 1]->end, end);
+
+	/*
+	 * Fill any gaps by tracking the previous memblks
+	 * end address and backfilling to it if needed.
+	 */
+	prev_end = blk[0]->end;
+	for (int i = 1; i < count; i++) {
+		struct numa_memblk *curr = blk[i];
+
+		if (prev_end >= curr->start) {
+			if (prev_end < curr->end)
+				prev_end = curr->end;
+		} else {
+			curr->start = prev_end;
+			prev_end = curr->end;
+		}
+	}
+	return 0;
+}
+
 #endif