Merge commit '5bc66170dc486556a1e36fd384463536573f4b82' into x86/urgent

From Borislav Petkov <bp@amd64.org>:

Below is a RAS fix which reverts the addition of a sysfs attribute
which we agreed is not needed, post-factum. And this should go in now
because that sysfs attribute is going to end up in 3.7 otherwise and
thus exposed to userspace; removing it then would be a lot harder.

This is done as a merge rather than a simple patch/cherry-pick since
the baseline for this patch was not in the previous x86/urgent.

Signed-off-by: H. Peter Anvin <hpa@linux.intel.com>

1 files changed, 43 insertions, 0 deletions

diff --git a/arch/arm64/include/asm/pgtable-2level-hwdef.h b/arch/arm64/include/asm/pgtable-2level-hwdef.h
new file mode 100644
index 00000000000..0a8ed3f94e9
--- /dev/null
+++ b/arch/arm64/include/asm/pgtable-2level-hwdef.h
@@ -0,0 +1,43 @@
+/*
+ * Copyright (C) 2012 ARM Ltd.
+ *
+ * This program is free software; you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License version 2 as
+ * published by the Free Software Foundation.
+ *
+ * This program is distributed in the hope that 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.
+ *
+ * You should have received a copy of the GNU General Public License
+ * along with this program.  If not, see <http://www.gnu.org/licenses/>.
+ */
+#ifndef __ASM_PGTABLE_2LEVEL_HWDEF_H
+#define __ASM_PGTABLE_2LEVEL_HWDEF_H
+
+/*
+ * With LPAE and 64KB pages, there are 2 levels of page tables. Each level has
+ * 8192 entries of 8 bytes each, occupying a 64KB page. Levels 0 and 1 are not
+ * used. The 2nd level table (PGD for Linux) can cover a range of 4TB, each
+ * entry representing 512MB. The user and kernel address spaces are limited to
+ * 512GB and therefore we only use 1024 entries in the PGD.
+ */
+#define PTRS_PER_PTE		8192
+#define PTRS_PER_PGD		1024
+
+/*
+ * PGDIR_SHIFT determines the size a top-level page table entry can map.
+ */
+#define PGDIR_SHIFT		29
+#define PGDIR_SIZE		(_AC(1, UL) << PGDIR_SHIFT)
+#define PGDIR_MASK		(~(PGDIR_SIZE-1))
+
+/*
+ * section address mask and size definitions.
+ */
+#define SECTION_SHIFT		29
+#define SECTION_SIZE		(_AC(1, UL) << SECTION_SHIFT)
+#define SECTION_MASK		(~(SECTION_SIZE-1))
+
+#endif