Merge android-4.4.110 (5cc8c2e) into msm-4.4

* refs/heads/tmp-5cc8c2e
  Linux 4.4.110
  kaiser: Set _PAGE_NX only if supported
  x86/kasan: Clear kasan_zero_page after TLB flush
  x86/vdso: Get pvclock data from the vvar VMA instead of the fixmap
  x86, vdso, pvclock: Simplify and speed up the vdso pvclock reader
  KPTI: Report when enabled
  KPTI: Rename to PAGE_TABLE_ISOLATION
  x86/kaiser: Move feature detection up
  kaiser: disabled on Xen PV
  x86/kaiser: Reenable PARAVIRT
  x86/paravirt: Dont patch flush_tlb_single
  kaiser: kaiser_flush_tlb_on_return_to_user() check PCID
  kaiser: asm/tlbflush.h handle noPGE at lower level
  kaiser: drop is_atomic arg to kaiser_pagetable_walk()
  kaiser: use ALTERNATIVE instead of x86_cr3_pcid_noflush
  x86/kaiser: Check boottime cmdline params
  x86/kaiser: Rename and simplify X86_FEATURE_KAISER handling
  kaiser: add "nokaiser" boot option, using ALTERNATIVE
  kaiser: fix unlikely error in alloc_ldt_struct()
  kaiser: _pgd_alloc() without __GFP_REPEAT to avoid stalls
  kaiser: paranoid_entry pass cr3 need to paranoid_exit
  kaiser: x86_cr3_pcid_noflush and x86_cr3_pcid_user
  kaiser: PCID 0 for kernel and 128 for user
  kaiser: load_new_mm_cr3() let SWITCH_USER_CR3 flush user
  kaiser: enhanced by kernel and user PCIDs
  kaiser: vmstat show NR_KAISERTABLE as nr_overhead
  kaiser: delete KAISER_REAL_SWITCH option
  kaiser: name that 0x1000 KAISER_SHADOW_PGD_OFFSET
  kaiser: cleanups while trying for gold link
  kaiser: kaiser_remove_mapping() move along the pgd
  kaiser: tidied up kaiser_add/remove_mapping slightly
  kaiser: tidied up asm/kaiser.h somewhat
  kaiser: ENOMEM if kaiser_pagetable_walk() NULL
  kaiser: fix perf crashes
  kaiser: fix regs to do_nmi() ifndef CONFIG_KAISER
  kaiser: KAISER depends on SMP
  kaiser: fix build and FIXME in alloc_ldt_struct()
  kaiser: stack map PAGE_SIZE at THREAD_SIZE-PAGE_SIZE
  kaiser: do not set _PAGE_NX on pgd_none
  kaiser: merged update
  KAISER: Kernel Address Isolation
  x86/boot: Add early cmdline parsing for options with arguments
  ANDROID: sdcardfs: Add default_normal option
  ANDROID: sdcardfs: notify lower file of opens

Conflicts:
	kernel/fork.c

Change-Id: I9c8c12e63321d79dc2c89fb470ca8de587366911
Signed-off-by: Srinivasarao P <spathi@codeaurora.org>

3 files changed, 85 insertions, 2 deletions

diff --git a/include/linux/kaiser.h b/include/linux/kaiser.h
new file mode 100644
index 000000000000..58c55b1589d0
--- /dev/null
+++ b/include/linux/kaiser.h
@@ -0,0 +1,52 @@
+#ifndef _LINUX_KAISER_H
+#define _LINUX_KAISER_H
+
+#ifdef CONFIG_PAGE_TABLE_ISOLATION
+#include <asm/kaiser.h>
+
+static inline int kaiser_map_thread_stack(void *stack)
+{
+	/*
+	 * Map that page of kernel stack on which we enter from user context.
+	 */
+	return kaiser_add_mapping((unsigned long)stack +
+			THREAD_SIZE - PAGE_SIZE, PAGE_SIZE, __PAGE_KERNEL);
+}
+
+static inline void kaiser_unmap_thread_stack(void *stack)
+{
+	/*
+	 * Note: may be called even when kaiser_map_thread_stack() failed.
+	 */
+	kaiser_remove_mapping((unsigned long)stack +
+			THREAD_SIZE - PAGE_SIZE, PAGE_SIZE);
+}
+#else
+
+/*
+ * These stubs are used whenever CONFIG_PAGE_TABLE_ISOLATION is off, which
+ * includes architectures that support KAISER, but have it disabled.
+ */
+
+static inline void kaiser_init(void)
+{
+}
+static inline int kaiser_add_mapping(unsigned long addr,
+				     unsigned long size, unsigned long flags)
+{
+	return 0;
+}
+static inline void kaiser_remove_mapping(unsigned long start,
+					 unsigned long size)
+{
+}
+static inline int kaiser_map_thread_stack(void *stack)
+{
+	return 0;
+}
+static inline void kaiser_unmap_thread_stack(void *stack)
+{
+}
+
+#endif /* !CONFIG_PAGE_TABLE_ISOLATION */
+#endif /* _LINUX_KAISER_H */
diff --git a/include/linux/mmzone.h b/include/linux/mmzone.h
index 721bdb0226bd..0db2f3cb1b6c 100644
--- a/include/linux/mmzone.h
+++ b/include/linux/mmzone.h
@@ -148,8 +148,9 @@ enum zone_stat_item {
 	NR_SLAB_RECLAIMABLE,
 	NR_SLAB_UNRECLAIMABLE,
 	NR_PAGETABLE,		/* used for pagetables */
-	NR_KERNEL_STACK,
 	/* Second 128 byte cacheline */
+	NR_KERNEL_STACK,
+	NR_KAISERTABLE,
 	NR_UNSTABLE_NFS,	/* NFS unstable pages */
 	NR_BOUNCE,
 	NR_VMSCAN_WRITE,
diff --git a/include/linux/percpu-defs.h b/include/linux/percpu-defs.h
index 8f16299ca068..8902f23bb770 100644
--- a/include/linux/percpu-defs.h
+++ b/include/linux/percpu-defs.h
@@ -35,6 +35,12 @@
 
 #endif
 
+#ifdef CONFIG_PAGE_TABLE_ISOLATION
+#define USER_MAPPED_SECTION "..user_mapped"
+#else
+#define USER_MAPPED_SECTION ""
+#endif
+
 /*
  * Base implementations of per-CPU variable declarations and definitions, where
  * the section in which the variable is to be placed is provided by the
@@ -115,6 +121,12 @@
 #define DEFINE_PER_CPU(type, name)					\
 	DEFINE_PER_CPU_SECTION(type, name, "")
 
+#define DECLARE_PER_CPU_USER_MAPPED(type, name)				\
+	DECLARE_PER_CPU_SECTION(type, name, USER_MAPPED_SECTION)
+
+#define DEFINE_PER_CPU_USER_MAPPED(type, name)				\
+	DEFINE_PER_CPU_SECTION(type, name, USER_MAPPED_SECTION)
+
 /*
  * Declaration/definition used for per-CPU variables that must come first in
  * the set of variables.
@@ -144,6 +156,14 @@
 	DEFINE_PER_CPU_SECTION(type, name, PER_CPU_SHARED_ALIGNED_SECTION) \
 	____cacheline_aligned_in_smp
 
+#define DECLARE_PER_CPU_SHARED_ALIGNED_USER_MAPPED(type, name)		\
+	DECLARE_PER_CPU_SECTION(type, name, USER_MAPPED_SECTION PER_CPU_SHARED_ALIGNED_SECTION) \
+	____cacheline_aligned_in_smp
+
+#define DEFINE_PER_CPU_SHARED_ALIGNED_USER_MAPPED(type, name)		\
+	DEFINE_PER_CPU_SECTION(type, name, USER_MAPPED_SECTION PER_CPU_SHARED_ALIGNED_SECTION) \
+	____cacheline_aligned_in_smp
+
 #define DECLARE_PER_CPU_ALIGNED(type, name)				\
 	DECLARE_PER_CPU_SECTION(type, name, PER_CPU_ALIGNED_SECTION)	\
 	____cacheline_aligned
@@ -162,11 +182,21 @@
 #define DEFINE_PER_CPU_PAGE_ALIGNED(type, name)				\
 	DEFINE_PER_CPU_SECTION(type, name, "..page_aligned")		\
 	__aligned(PAGE_SIZE)
+/*
+ * Declaration/definition used for per-CPU variables that must be page aligned and need to be mapped in user mode.
+ */
+#define DECLARE_PER_CPU_PAGE_ALIGNED_USER_MAPPED(type, name)		\
+	DECLARE_PER_CPU_SECTION(type, name, USER_MAPPED_SECTION"..page_aligned") \
+	__aligned(PAGE_SIZE)
+
+#define DEFINE_PER_CPU_PAGE_ALIGNED_USER_MAPPED(type, name)		\
+	DEFINE_PER_CPU_SECTION(type, name, USER_MAPPED_SECTION"..page_aligned") \
+	__aligned(PAGE_SIZE)
 
 /*
  * Declaration/definition used for per-CPU variables that must be read mostly.
  */
-#define DECLARE_PER_CPU_READ_MOSTLY(type, name)			\
+#define DECLARE_PER_CPU_READ_MOSTLY(type, name)				\
 	DECLARE_PER_CPU_SECTION(type, name, "..read_mostly")
 
 #define DEFINE_PER_CPU_READ_MOSTLY(type, name)				\