2 * self test for change_page_attr.
4 * Clears the global bit on random pages in the direct mapping, then reverts
5 * and compares page tables forwards and afterwards.
7 #include <linux/bootmem.h>
8 #include <linux/random.h>
9 #include <linux/kernel.h>
10 #include <linux/init.h>
13 #include <asm/cacheflush.h>
14 #include <asm/pgtable.h>
15 #include <asm/kdebug.h>
19 LOWEST_LEVEL = PG_LEVEL_4K,
21 LPS = (1 << PMD_SHIFT),
22 #elif defined(CONFIG_X86_PAE)
23 LPS = (1 << PMD_SHIFT),
31 # include <asm/proto.h>
32 # define max_mapped end_pfn_map
34 # define max_mapped max_low_pfn
38 long lpg, gpg, spg, exec;
39 long min_exec, max_exec;
42 static __init int print_split(struct split_state *s)
44 long i, expected, missed = 0;
48 s->lpg = s->gpg = s->spg = s->exec = 0;
51 for (i = 0; i < max_mapped; ) {
52 unsigned long addr = (unsigned long)__va(i << PAGE_SHIFT);
56 pte = lookup_address(addr, &level);
60 printk(KERN_INFO "CPA %lx no pte level %d\n",
69 if (level == 2 && sizeof(long) == 8) {
72 } else if (level != LOWEST_LEVEL) {
73 if (!(pte_val(*pte) & _PAGE_PSE)) {
75 "%lx level %d but not PSE %Lx\n",
76 addr, level, (u64)pte_val(*pte));
85 if (!(pte_val(*pte) & _PAGE_NX)) {
87 if (addr < s->min_exec)
89 if (addr > s->max_exec)
94 "CPA mapping 4k %lu large %lu gb %lu x %lu[%lx-%lx] miss %lu\n",
95 s->spg, s->lpg, s->gpg, s->exec,
96 s->min_exec != ~0UL ? s->min_exec : 0, s->max_exec, missed);
98 expected = (s->gpg*GPS + s->lpg*LPS)/PAGE_SIZE + s->spg + missed;
100 printk(KERN_ERR "CPA max_mapped %lu but expected %lu\n",
101 max_mapped, expected);
107 static unsigned long __initdata addr[NTEST];
108 static unsigned int __initdata len[NTEST];
110 /* Change the global bit on random pages in the direct mapping */
111 static __init int exercise_pageattr(void)
113 struct split_state sa, sb, sc;
121 printk(KERN_INFO "CPA exercising pageattr\n");
123 bm = vmalloc((max_mapped + 7) / 8);
125 printk(KERN_ERR "CPA Cannot vmalloc bitmap\n");
128 memset(bm, 0, (max_mapped + 7) / 8);
130 failed += print_split(&sa);
133 for (i = 0; i < NTEST; i++) {
134 unsigned long pfn = random32() % max_mapped;
136 addr[i] = (unsigned long)__va(pfn << PAGE_SHIFT);
137 len[i] = random32() % 100;
138 len[i] = min_t(unsigned long, len[i], max_mapped - pfn - 1);
144 pte0 = pfn_pte(0, __pgprot(0)); /* shut gcc up */
146 for (k = 0; k < len[i]; k++) {
147 pte = lookup_address(addr[i] + k*PAGE_SIZE, &level);
148 if (!pte || pgprot_val(pte_pgprot(*pte)) == 0) {
155 if (pgprot_val(pte_pgprot(*pte)) !=
156 pgprot_val(pte_pgprot(pte0))) {
161 if (test_bit(pfn + k, bm)) {
165 __set_bit(pfn + k, bm);
167 if (!addr[i] || !pte || !k) {
172 err = change_page_attr_addr(addr[i], len[i],
173 pte_pgprot(pte_clrhuge(pte_clrglobal(pte0))));
175 printk(KERN_ERR "CPA %d failed %d\n", i, err);
179 pte = lookup_address(addr[i], &level);
180 if (!pte || pte_global(*pte) || pte_huge(*pte)) {
181 printk(KERN_ERR "CPA %lx: bad pte %Lx\n", addr[i],
182 pte ? (u64)pte_val(*pte) : 0ULL);
185 if (level != LOWEST_LEVEL) {
186 printk(KERN_ERR "CPA %lx: unexpected level %d\n",
195 failed += print_split(&sb);
197 printk(KERN_INFO "CPA reverting everything\n");
198 for (i = 0; i < NTEST; i++) {
201 pte = lookup_address(addr[i], &level);
203 printk(KERN_ERR "CPA lookup of %lx failed\n", addr[i]);
207 err = change_page_attr_addr(addr[i], len[i],
208 pte_pgprot(pte_mkglobal(*pte)));
210 printk(KERN_ERR "CPA reverting failed: %d\n", err);
213 pte = lookup_address(addr[i], &level);
214 if (!pte || !pte_global(*pte)) {
215 printk(KERN_ERR "CPA %lx: bad pte after revert %Lx\n",
216 addr[i], pte ? (u64)pte_val(*pte) : 0ULL);
223 failed += print_split(&sc);
226 printk(KERN_ERR "CPA selftests NOT PASSED. Please report.\n");
229 printk(KERN_INFO "CPA selftests PASSED\n");
234 module_init(exercise_pageattr);