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

Pull x86 fixes from Thomas Gleixner:
 "Misc fixes:
   - gold linker build fix
   - noxsave command line parsing fix
   - bugfix for NX setup
   - microcode resume path bug fix
   - _TIF_NOHZ versus TIF_NOHZ bugfix as discussed in the mysterious
     lockup thread"

* 'x86-urgent-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip:
  x86, syscall: Fix _TIF_NOHZ handling in syscall_trace_enter_phase1
  x86, kaslr: Handle Gold linker for finding bss/brk
  x86, mm: Set NX across entire PMD at boot
  x86, microcode: Update BSPs microcode on resume
  x86: Require exact match for 'noxsave' command line option

5 files changed, 31 insertions, 3 deletions

diff --git a/arch/x86/kernel/cpu/common.c b/arch/x86/kernel/cpu/common.c
index 4b4f78c9ba19..cfa9b5b2c27a 100644
--- a/arch/x86/kernel/cpu/common.c
+++ b/arch/x86/kernel/cpu/common.c
@@ -146,6 +146,8 @@ EXPORT_PER_CPU_SYMBOL_GPL(gdt_page);
 
 static int __init x86_xsave_setup(char *s)
 {
+        if (strlen(s))
+                return 0;
         setup_clear_cpu_cap(X86_FEATURE_XSAVE);
         setup_clear_cpu_cap(X86_FEATURE_XSAVEOPT);
         setup_clear_cpu_cap(X86_FEATURE_XSAVES);
diff --git a/arch/x86/kernel/cpu/microcode/core.c b/arch/x86/kernel/cpu/microcode/core.c
index dd9d6190b08d..2ce9051174e6 100644
--- a/arch/x86/kernel/cpu/microcode/core.c
+++ b/arch/x86/kernel/cpu/microcode/core.c
@@ -465,6 +465,14 @@ static void mc_bp_resume(void)
 
         if (uci->valid && uci->mc)
                 microcode_ops->apply_microcode(cpu);
+        else if (!uci->mc)
+                /*
+                 * We might resume and not have applied late microcode but still
+                 * have a newer patch stashed from the early loader. We don't
+                 * have it in uci->mc so we have to load it the same way we're
+                 * applying patches early on the APs.
+                 */
+                load_ucode_ap();
 }
 
 static struct syscore_ops mc_syscore_ops = {
diff --git a/arch/x86/kernel/ptrace.c b/arch/x86/kernel/ptrace.c
index 749b0e423419..e510618b2e91 100644
--- a/arch/x86/kernel/ptrace.c
+++ b/arch/x86/kernel/ptrace.c
@@ -1484,7 +1484,7 @@ unsigned long syscall_trace_enter_phase1(struct pt_regs *regs, u32 arch)
          */
         if (work & _TIF_NOHZ) {
                 user_exit();
-                work &= ~TIF_NOHZ;
+                work &= ~_TIF_NOHZ;
         }
 
 #ifdef CONFIG_SECCOMP
diff --git a/arch/x86/mm/init_64.c b/arch/x86/mm/init_64.c
index 4cb8763868fc..4e5dfec750fc 100644
--- a/arch/x86/mm/init_64.c
+++ b/arch/x86/mm/init_64.c
@@ -1123,7 +1123,7 @@ void mark_rodata_ro(void)
         unsigned long end = (unsigned long) &__end_rodata_hpage_align;
         unsigned long text_end = PFN_ALIGN(&__stop___ex_table);
         unsigned long rodata_end = PFN_ALIGN(&__end_rodata);
-        unsigned long all_end = PFN_ALIGN(&_end);
+        unsigned long all_end;
 
         printk(KERN_INFO "Write protecting the kernel read-only data: %luk\n",
                (end - start) >> 10);
@@ -1134,7 +1134,16 @@ void mark_rodata_ro(void)
         /*
          * The rodata/data/bss/brk section (but not the kernel text!)
          * should also be not-executable.
+         *
+         * We align all_end to PMD_SIZE because the existing mapping
+         * is a full PMD. If we would align _brk_end to PAGE_SIZE we
+         * split the PMD and the reminder between _brk_end and the end
+         * of the PMD will remain mapped executable.
+         *
+         * Any PMD which was setup after the one which covers _brk_end
+         * has been zapped already via cleanup_highmem().
          */
+        all_end = roundup((unsigned long)_brk_end, PMD_SIZE);
         set_memory_nx(rodata_start, (all_end - rodata_start) >> PAGE_SHIFT);
 
         rodata_test();
diff --git a/arch/x86/tools/calc_run_size.pl b/arch/x86/tools/calc_run_size.pl
index 0b0b124d3ece..23210baade2d 100644
--- a/arch/x86/tools/calc_run_size.pl
+++ b/arch/x86/tools/calc_run_size.pl
@@ -19,7 +19,16 @@ while (<>) {
                 if ($file_offset == 0) {
                         $file_offset = $offset;
                 } elsif ($file_offset != $offset) {
-                        die ".bss and .brk lack common file offset\n";
+                        # BFD linker shows the same file offset in ELF.
+                        # Gold linker shows them as consecutive.
+                        next if ($file_offset + $mem_size == $offset + $size);
+
+                        printf STDERR "file_offset: 0x%lx\n", $file_offset;
+                        printf STDERR "mem_size: 0x%lx\n", $mem_size;
+                        printf STDERR "offset: 0x%lx\n", $offset;
+                        printf STDERR "size: 0x%lx\n", $size;
+
+                        die ".bss and .brk are non-contiguous\n";
                 }
         }
 }