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-rw-r--r--arch/x86/mm/Makefile_321
-rw-r--r--arch/x86/mm/Makefile_641
-rw-r--r--arch/x86/mm/pageattr-test.c233
3 files changed, 235 insertions, 0 deletions
diff --git a/arch/x86/mm/Makefile_32 b/arch/x86/mm/Makefile_32
index 6a5e981981f..be2f55160bf 100644
--- a/arch/x86/mm/Makefile_32
+++ b/arch/x86/mm/Makefile_32
@@ -4,6 +4,7 @@
obj-y := init_32.o pgtable_32.o fault_32.o ioremap_32.o extable.o pageattr_32.o mmap.o
+obj-$(CONFIG_CPA_DEBUG) += pageattr-test.o
obj-$(CONFIG_NUMA) += discontig_32.o
obj-$(CONFIG_HUGETLB_PAGE) += hugetlbpage.o
obj-$(CONFIG_HIGHMEM) += highmem_32.o
diff --git a/arch/x86/mm/Makefile_64 b/arch/x86/mm/Makefile_64
index 09c997fe585..cb723167631 100644
--- a/arch/x86/mm/Makefile_64
+++ b/arch/x86/mm/Makefile_64
@@ -7,3 +7,4 @@ obj-$(CONFIG_HUGETLB_PAGE) += hugetlbpage.o
obj-$(CONFIG_NUMA) += numa_64.o
obj-$(CONFIG_K8_NUMA) += k8topology_64.o
obj-$(CONFIG_ACPI_NUMA) += srat_64.o
+obj-$(CONFIG_CPA_DEBUG) += pageattr-test.o
diff --git a/arch/x86/mm/pageattr-test.c b/arch/x86/mm/pageattr-test.c
new file mode 100644
index 00000000000..4b22eb47f23
--- /dev/null
+++ b/arch/x86/mm/pageattr-test.c
@@ -0,0 +1,233 @@
+/*
+ * self test for change_page_attr.
+ *
+ * Clears the global bit on random pages in the direct mapping, then reverts
+ * and compares page tables forwards and afterwards.
+ */
+
+#include <linux/mm.h>
+#include <linux/random.h>
+#include <linux/kernel.h>
+#include <linux/init.h>
+#include <linux/bootmem.h>
+#include <asm/cacheflush.h>
+#include <asm/pgtable.h>
+#include <asm/kdebug.h>
+
+enum {
+ NTEST = 400,
+#ifdef CONFIG_X86_64
+ LOWEST_LEVEL = 4,
+ LPS = (1 << PMD_SHIFT),
+#elif defined(CONFIG_X86_PAE)
+ LOWEST_LEVEL = 3,
+ LPS = (1 << PMD_SHIFT),
+#else
+ LOWEST_LEVEL = 3, /* lookup_address lies here */
+ LPS = (1 << 22),
+#endif
+ GPS = (1<<30)
+};
+
+#ifdef CONFIG_X86_64
+#include <asm/proto.h>
+#define max_mapped end_pfn_map
+#else
+#define max_mapped max_low_pfn
+#endif
+
+struct split_state {
+ long lpg, gpg, spg, exec;
+ long min_exec, max_exec;
+};
+
+static __init int print_split(struct split_state *s)
+{
+ int printed = 0;
+ long i, expected, missed = 0;
+ int err = 0;
+
+ s->lpg = s->gpg = s->spg = s->exec = 0;
+ s->min_exec = ~0UL;
+ s->max_exec = 0;
+ for (i = 0; i < max_mapped; ) {
+ int level;
+ pte_t *pte;
+ unsigned long adr = (unsigned long)__va(i << PAGE_SHIFT);
+
+ pte = lookup_address(adr, &level);
+ if (!pte) {
+ if (!printed) {
+ dump_pagetable(adr);
+ printk("CPA %lx no pte level %d\n", adr, level);
+ printed = 1;
+ }
+ missed++;
+ i++;
+ continue;
+ }
+
+ if (level == 2 && sizeof(long) == 8) {
+ s->gpg++;
+ i += GPS/PAGE_SIZE;
+ } else if (level != LOWEST_LEVEL) {
+ if (!(pte_val(*pte) & _PAGE_PSE)) {
+ printk("%lx level %d but not PSE %Lx\n",
+ adr, level, (u64)pte_val(*pte));
+ err = 1;
+ }
+ s->lpg++;
+ i += LPS/PAGE_SIZE;
+ } else {
+ s->spg++;
+ i++;
+ }
+ if (!(pte_val(*pte) & _PAGE_NX)) {
+ s->exec++;
+ if (adr < s->min_exec)
+ s->min_exec = adr;
+ if (adr > s->max_exec)
+ s->max_exec = adr;
+ }
+ }
+ printk("CPA mapping 4k %lu large %lu gb %lu x %lu[%lx-%lx] miss %lu\n",
+ s->spg, s->lpg, s->gpg, s->exec,
+ s->min_exec != ~0UL ? s->min_exec : 0, s->max_exec, missed);
+ expected = (s->gpg*GPS + s->lpg*LPS)/PAGE_SIZE + s->spg + missed;
+ if (expected != i) {
+ printk("CPA max_mapped %lu but expected %lu\n",
+ max_mapped, expected);
+ return 1;
+ }
+ return err;
+}
+
+static __init int state_same(struct split_state *a, struct split_state *b)
+{
+ return a->lpg == b->lpg && a->gpg == b->gpg && a->spg == b->spg &&
+ a->exec == b->exec;
+}
+
+static unsigned long addr[NTEST] __initdata;
+static unsigned len[NTEST] __initdata;
+
+/* Change the global bit on random pages in the direct mapping */
+static __init int exercise_pageattr(void)
+{
+ int i, k;
+ pte_t *pte, pte0;
+ int level;
+ int err;
+ struct split_state sa, sb, sc;
+ int failed = 0;
+ unsigned long *bm;
+
+ printk("CPA exercising pageattr\n");
+
+ bm = vmalloc((max_mapped + 7) / 8);
+ if (!bm) {
+ printk("CPA Cannot vmalloc bitmap\n");
+ return -ENOMEM;
+ }
+ memset(bm, 0, (max_mapped + 7) / 8);
+
+ failed += print_split(&sa);
+ srandom32(100);
+ for (i = 0; i < NTEST; i++) {
+ unsigned long pfn = random32() % max_mapped;
+ addr[i] = (unsigned long)__va(pfn << PAGE_SHIFT);
+ len[i] = random32() % 100;
+ len[i] = min_t(unsigned long, len[i], max_mapped - pfn - 1);
+ if (len[i] == 0)
+ len[i] = 1;
+
+ pte = NULL;
+ pte0 = pfn_pte(0, __pgprot(0)); /* shut gcc up */
+ for (k = 0; k < len[i]; k++) {
+ pte = lookup_address(addr[i] + k*PAGE_SIZE, &level);
+ if (!pte || pgprot_val(pte_pgprot(*pte)) == 0) {
+ addr[i] = 0;
+ break;
+ }
+ if (k == 0)
+ pte0 = *pte;
+ else if (pgprot_val(pte_pgprot(*pte)) !=
+ pgprot_val(pte_pgprot(pte0))) {
+ len[i] = k;
+ break;
+ }
+ if (test_bit(pfn + k, bm)) {
+ len[i] = k;
+ break;
+ }
+ __set_bit(pfn + k, bm);
+ }
+ if (!addr[i] || !pte || !k) {
+ addr[i] = 0;
+ continue;
+ }
+
+ err = change_page_attr(virt_to_page(addr[i]), len[i],
+ pte_pgprot(pte_clrhuge(pte_clrglobal(pte0))));
+ if (err < 0) {
+ printk("CPA %d failed %d\n", i, err);
+ failed++;
+ }
+
+ pte = lookup_address(addr[i], &level);
+ if (!pte || pte_global(*pte) || pte_huge(*pte)) {
+ printk("CPA %lx: bad pte %Lx\n", addr[i],
+ pte ? (u64)pte_val(*pte) : 0ULL);
+ failed++;
+ }
+ if (level != LOWEST_LEVEL) {
+ printk("CPA %lx: unexpected level %d\n", addr[i],
+ level);
+ failed++;
+ }
+
+ }
+ vfree(bm);
+ global_flush_tlb();
+
+ failed += print_split(&sb);
+
+ printk("CPA reverting everything\n");
+ for (i = 0; i < NTEST; i++) {
+ if (!addr[i])
+ continue;
+ pte = lookup_address(addr[i], &level);
+ if (!pte) {
+ printk("CPA lookup of %lx failed\n", addr[i]);
+ failed++;
+ continue;
+ }
+ err = change_page_attr(virt_to_page(addr[i]), len[i],
+ pte_pgprot(pte_mkglobal(*pte)));
+ if (err < 0) {
+ printk("CPA reverting failed: %d\n", err);
+ failed++;
+ }
+ pte = lookup_address(addr[i], &level);
+ if (!pte || !pte_global(*pte)) {
+ printk("CPA %lx: bad pte after revert %Lx\n", addr[i],
+ pte ? (u64)pte_val(*pte) : 0ULL);
+ failed++;
+ }
+
+ }
+ global_flush_tlb();
+
+ failed += print_split(&sc);
+ if (!state_same(&sa, &sc))
+ failed++;
+
+ if (failed)
+ printk("CPA selftests NOT PASSED. Please report.\n");
+ else
+ printk("CPA selftests PASSED\n");
+
+ return 0;
+}
+
+module_init(exercise_pageattr);
generated by cgit v1.2.3 (git 2.25.1) at 2024-12-16 16:28:02 +0000