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

Pull x86 fixes from Ingo Molnar:
 "Misc changes:
   - fix lguest bug
   - fix /proc/meminfo output on certain configs
   - fix pvclock bug
   - fix reboot on certain iMacs by adding new reboot quirk
   - fix bootup crash
   - fix FPU boot line option parsing
   - add more x86 self-tests
   - small cleanups, documentation improvements, etc"

* 'x86-urgent-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip:
  x86/cpu/amd: Remove an unneeded condition in srat_detect_node()
  x86/vdso/pvclock: Protect STABLE check with the seqcount
  x86/mm: Improve switch_mm() barrier comments
  selftests/x86: Test __kernel_sigreturn and __kernel_rt_sigreturn
  x86/reboot/quirks: Add iMac10,1 to pci_reboot_dmi_table[]
  lguest: Map switcher text R/O
  x86/boot: Hide local labels in verify_cpu()
  x86/fpu: Disable AVX when eagerfpu is off
  x86/fpu: Disable MPX when eagerfpu is off
  x86/fpu: Disable XGETBV1 when no XSAVE
  x86/fpu: Fix early FPU command-line parsing
  x86/mm: Use PAGE_ALIGNED instead of IS_ALIGNED
  selftests/x86: Disable the ldt_gdt_64 test for now
  x86/mm/pat: Make split_page_count() check for empty levels to fix /proc/meminfo output
  x86/boot: Double BOOT_HEAP_SIZE to 64KB
  x86/mm: Add barriers and document switch_mm()-vs-flush synchronization

2 files changed, 92 insertions, 2 deletions

diff --git a/tools/testing/selftests/x86/Makefile b/tools/testing/selftests/x86/Makefile
index eabcff411984..d0c473f65850 100644
--- a/tools/testing/selftests/x86/Makefile
+++ b/tools/testing/selftests/x86/Makefile
@@ -4,9 +4,11 @@ include ../lib.mk
 
 .PHONY: all all_32 all_64 warn_32bit_failure clean
 
-TARGETS_C_BOTHBITS := single_step_syscall sysret_ss_attrs ldt_gdt syscall_nt ptrace_syscall
+TARGETS_C_BOTHBITS := single_step_syscall sysret_ss_attrs syscall_nt ptrace_syscall
 TARGETS_C_32BIT_ONLY := entry_from_vm86 syscall_arg_fault sigreturn test_syscall_vdso unwind_vdso \
-                        test_FCMOV test_FCOMI test_FISTTP
+                        test_FCMOV test_FCOMI test_FISTTP \
+                        ldt_gdt \
+                        vdso_restorer
 
 TARGETS_C_32BIT_ALL := $(TARGETS_C_BOTHBITS) $(TARGETS_C_32BIT_ONLY)
 BINARIES_32 := $(TARGETS_C_32BIT_ALL:%=%_32)
diff --git a/tools/testing/selftests/x86/vdso_restorer.c b/tools/testing/selftests/x86/vdso_restorer.c
new file mode 100644
index 000000000000..cb038424a403
--- /dev/null
+++ b/tools/testing/selftests/x86/vdso_restorer.c
@@ -0,0 +1,88 @@
+/*
+ * vdso_restorer.c - tests vDSO-based signal restore
+ * Copyright (c) 2015 Andrew Lutomirski
+ *
+ * This program is free software; you can redistribute it and/or modify
+ * it under the terms and conditions of the GNU General Public License,
+ * version 2, as published by the Free Software Foundation.
+ *
+ * This program is distributed in the hope it will be useful, but
+ * WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
+ * General Public License for more details.
+ *
+ * This makes sure that sa_restorer == NULL keeps working on 32-bit
+ * configurations.  Modern glibc doesn't use it under any circumstances,
+ * so it's easy to overlook breakage.
+ *
+ * 64-bit userspace has never supported sa_restorer == NULL, so this is
+ * 32-bit only.
+ */
+
+#define _GNU_SOURCE
+
+#include <err.h>
+#include <stdio.h>
+#include <string.h>
+#include <signal.h>
+#include <unistd.h>
+#include <syscall.h>
+#include <sys/syscall.h>
+
+/* Open-code this -- the headers are too messy to easily use them. */
+struct real_sigaction {
+        void *handler;
+        unsigned long flags;
+        void *restorer;
+        unsigned int mask[2];
+};
+
+static volatile sig_atomic_t handler_called;
+
+static void handler_with_siginfo(int sig, siginfo_t *info, void *ctx_void)
+{
+        handler_called = 1;
+}
+
+static void handler_without_siginfo(int sig)
+{
+        handler_called = 1;
+}
+
+int main()
+{
+        int nerrs = 0;
+        struct real_sigaction sa;
+
+        memset(&sa, 0, sizeof(sa));
+        sa.handler = handler_with_siginfo;
+        sa.flags = SA_SIGINFO;
+        sa.restorer = NULL;     /* request kernel-provided restorer */
+
+        if (syscall(SYS_rt_sigaction, SIGUSR1, &sa, NULL, 8) != 0)
+                err(1, "raw rt_sigaction syscall");
+
+        raise(SIGUSR1);
+
+        if (handler_called) {
+                printf("[OK]\tSA_SIGINFO handler returned successfully\n");
+        } else {
+                printf("[FAIL]\tSA_SIGINFO handler was not called\n");
+                nerrs++;
+        }
+
+        sa.flags = 0;
+        sa.handler = handler_without_siginfo;
+        if (syscall(SYS_sigaction, SIGUSR1, &sa, 0) != 0)
+                err(1, "raw sigaction syscall");
+        handler_called = 0;
+
+        raise(SIGUSR1);
+
+        if (handler_called) {
+                printf("[OK]\t!SA_SIGINFO handler returned successfully\n");
+        } else {
+                printf("[FAIL]\t!SA_SIGINFO handler was not called\n");
+                nerrs++;
+        }
+}