Merge branch 'uaccess' into fixes

diff --cc arch/arm/Kconfig
index 1c50210,e15d5ed..a7a2e32
--- 1/arch/arm/Kconfig
--- 2/arch/arm/Kconfig
+++ b/arch/arm/Kconfig
@@@ -1693,13 -1693,22 +1693,28 @@@ config HIGHME
  config HIGHPTE
        bool "Allocate 2nd-level pagetables from highmem"
        depends on HIGHMEM
 +      help
 +        The VM uses one page of physical memory for each page table.
 +        For systems with a lot of processes, this can use a lot of
 +        precious low memory, eventually leading to low memory being
 +        consumed by page tables.  Setting this option will allow
 +        user-space 2nd level page tables to reside in high memory.
  
+ config CPU_SW_DOMAIN_PAN
+       bool "Enable use of CPU domains to implement privileged no-access"
+       depends on MMU && !ARM_LPAE
+       default y
+       help
+         Increase kernel security by ensuring that normal kernel accesses
+         are unable to access userspace addresses.  This can help prevent
+         use-after-free bugs becoming an exploitable privilege escalation
+         by ensuring that magic values (such as LIST_POISON) will always
+         fault when dereferenced.
+ 
+         CPUs with low-vector mappings use a best-efforts implementation.
+         Their lower 1MB needs to remain accessible for the vectors, but
+         the remainder of userspace will become appropriately inaccessible.
+ 
  config HW_PERF_EVENTS
        bool "Enable hardware performance counter support for perf events"
        depends on PERF_EVENTS

diff --cc arch/arm/kernel/armksyms.c
Simple merge

diff --cc arch/arm/kernel/entry-armv.S
Simple merge

diff --cc arch/arm/kernel/entry-common.S
Simple merge

diff --cc arch/arm/kernel/head.S
Simple merge

diff --cc arch/arm/lib/uaccess_with_memcpy.c
Simple merge

diff --cc arch/arm/mm/mmu.c
Simple merge