x86/pkeys/selftests: Save off 'prot' for allocations

This makes it possible to to tell what 'prot' a given allocation
is supposed to have. That way, if we want to change just the
pkey, we know what 'prot' to pass to mprotect_pkey().

Also, keep a record of the most recent allocation so the tests
can easily find it.

Signed-off-by: Dave Hansen <[e-mail]>
Cc: Andrew Morton <[e-mail]>
Cc: Dave Hansen <[e-mail]>
Cc: Linus Torvalds <[e-mail]>
Cc: Michael Ellermen <[e-mail]>
Cc: Peter Zijlstra <[e-mail]>
Cc: Ram Pai <[e-mail]>
Cc: Shuah Khan <[e-mail]>
Cc: Thomas Gleixner <[e-mail]>
Cc: [e-mail]
Link: http://lkml.kernel.org/r/[e-mail]
Signed-off-by: Ingo Molnar <[e-mail]>

tools/testing/selftests/x86/protection_keys.c

···
 struct pkey_malloc_record {
 	void *ptr;
 	long size;
+	int prot;
 };
 struct pkey_malloc_record *pkey_malloc_records;
+struct pkey_malloc_record *pkey_last_malloc_record;
 long nr_pkey_malloc_records;
-void record_pkey_malloc(void *ptr, long size)
+void record_pkey_malloc(void *ptr, long size, int prot)
 {
 	long i;
 	struct pkey_malloc_record *rec = NULL;
···
 		(int)(rec - pkey_malloc_records), rec, ptr, size);
 	rec->ptr = ptr;
 	rec->size = size;
+	rec->prot = prot;
+	pkey_last_malloc_record = rec;
 	nr_pkey_malloc_records++;
 }
 
···
 	pkey_assert(ptr != (void *)-1);
 	ret = mprotect_pkey((void *)ptr, PAGE_SIZE, prot, pkey);
 	pkey_assert(!ret);
-	record_pkey_malloc(ptr, size);
+	record_pkey_malloc(ptr, size, prot);
 	rdpkru();
 
 	dprintf1("%s() for pkey %d @ %p\n", __func__, pkey, ptr);
···
 	size = ALIGN_UP(size, HPAGE_SIZE * 2);
 	ptr = mmap(NULL, size, PROT_NONE, MAP_ANONYMOUS|MAP_PRIVATE, -1, 0);
 	pkey_assert(ptr != (void *)-1);
-	record_pkey_malloc(ptr, size);
+	record_pkey_malloc(ptr, size, prot);
 	mprotect_pkey(ptr, size, prot, pkey);
 
 	dprintf1("unaligned ptr: %p\n", ptr);
···
 	pkey_assert(ptr != (void *)-1);
 	mprotect_pkey(ptr, size, prot, pkey);
 
-	record_pkey_malloc(ptr, size);
+	record_pkey_malloc(ptr, size, prot);
 
 	dprintf1("mmap()'d hugetlbfs for pkey %d @ %p\n", pkey, ptr);
 	return ptr;
···
 
 	mprotect_pkey(ptr, size, prot, pkey);
 
-	record_pkey_malloc(ptr, size);
+	record_pkey_malloc(ptr, size, prot);
 
 	dprintf1("mmap()'d for pkey %d @ %p\n", pkey, ptr);
 	close(fd);