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

…inux/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

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);

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 = {

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

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();

arch/x86/tools/calc_run_size.pl

@@ -19,7 +19,16 @@
 		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";
 		}
 	}
 }