Merge branch 'x86-urgent-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip

Pull x86 fixes from Thomas Gleixner:
 "A set of fixes for x86:

   - Fix the swapped outb() parameters in the KASLR code

   - Fix the PKEY handling at fork which missed to preserve the pkey
     state for the child. Comes with a test case to validate that.

   - Fix the entry stack handling for XEN PV to respect that XEN PV
     systems enter the function already on the current thread stack and
     not on the trampoline.

   - Fix kexec load failure caused by using a stale value when the
     kexec_buf structure is reused for subsequent allocations.

   - Fix a bogus sizeof() in the memory encryption code

   - Enforce PCI dependency for the Intel Low Power Subsystem

   - Enforce PCI_LOCKLESS_CONFIG when PCI is enabled"

* 'x86-urgent-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip:
  x86/Kconfig: Select PCI_LOCKLESS_CONFIG if PCI is enabled
  x86/entry/64/compat: Fix stack switching for XEN PV
  x86/kexec: Fix a kexec_file_load() failure
  x86/mm/mem_encrypt: Fix erroneous sizeof()
  x86/selftests/pkeys: Fork() to check for state being preserved
  x86/pkeys: Properly copy pkey state at fork()
  x86/kaslr: Fix incorrect i8254 outb() parameters
  x86/intel/lpss: Make PCI dependency explicit

1 files changed, 31 insertions, 10 deletions

diff --git a/tools/testing/selftests/x86/protection_keys.c b/tools/testing/selftests/x86/protection_keys.c
index 460b4bdf4c1e..5d546dcdbc80 100644
--- a/tools/testing/selftests/x86/protection_keys.c
+++ b/tools/testing/selftests/x86/protection_keys.c
@@ -1133,6 +1133,21 @@ void test_pkey_syscalls_bad_args(int *ptr, u16 pkey)
         pkey_assert(err);
 }
 
+void become_child(void)
+{
+        pid_t forkret;
+
+        forkret = fork();
+        pkey_assert(forkret >= 0);
+        dprintf3("[%d] fork() ret: %d\n", getpid(), forkret);
+
+        if (!forkret) {
+                /* in the child */
+                return;
+        }
+        exit(0);
+}
+
 /* Assumes that all pkeys other than 'pkey' are unallocated */
 void test_pkey_alloc_exhaust(int *ptr, u16 pkey)
 {
@@ -1141,7 +1156,7 @@ void test_pkey_alloc_exhaust(int *ptr, u16 pkey)
         int nr_allocated_pkeys = 0;
         int i;
 
-        for (i = 0; i < NR_PKEYS*2; i++) {
+        for (i = 0; i < NR_PKEYS*3; i++) {
                 int new_pkey;
                 dprintf1("%s() alloc loop: %d\n", __func__, i);
                 new_pkey = alloc_pkey();
@@ -1152,21 +1167,27 @@ void test_pkey_alloc_exhaust(int *ptr, u16 pkey)
                 if ((new_pkey == -1) && (errno == ENOSPC)) {
                         dprintf2("%s() failed to allocate pkey after %d tries\n",
                                 __func__, nr_allocated_pkeys);
-                        break;
+                } else {
+                        /*
+                         * Ensure the number of successes never
+                         * exceeds the number of keys supported
+                         * in the hardware.
+                         */
+                        pkey_assert(nr_allocated_pkeys < NR_PKEYS);
+                        allocated_pkeys[nr_allocated_pkeys++] = new_pkey;
                 }
-                pkey_assert(nr_allocated_pkeys < NR_PKEYS);
-                allocated_pkeys[nr_allocated_pkeys++] = new_pkey;
+
+                /*
+                 * Make sure that allocation state is properly
+                 * preserved across fork().
+                 */
+                if (i == NR_PKEYS*2)
+                        become_child();
         }
 
         dprintf3("%s()::%d\n", __func__, __LINE__);
 
         /*
-         * ensure it did not reach the end of the loop without
-         * failure:
-         */
-        pkey_assert(i < NR_PKEYS*2);
-
-        /*
          * There are 16 pkeys supported in hardware.  Three are
          * allocated by the time we get here:
          *   1. The default key (0)