Merge remote-tracking branch 'lts/linux-4.4.y' into linux-linaro-lsk-v4.4

[firefly-linux-kernel-4.4.55.git] / arch / arm64 / kernel / entry.S

diff --git a/arch/arm64/kernel/entry.S b/arch/arm64/kernel/entry.S
index 1f7f5a2b61bf0de999d80e6ced16bec120f716b6..588c8e1778d44a6cde02ef8ebb4b6db33652b809 100644 (file)
--- a/arch/arm64/kernel/entry.S
+++ b/arch/arm64/kernel/entry.S
@@ -28,6 +28,7 @@
 #include <asm/errno.h>
 #include <asm/esr.h>
 #include <asm/irq.h>
+#include <asm/memory.h>
 #include <asm/thread_info.h>
 #include <asm/unistd.h>
 
@@ -97,7 +98,13 @@
        mov     x29, xzr                        // fp pointed to user-space
        .else
        add     x21, sp, #S_FRAME_SIZE
-       .endif
+       get_thread_info tsk
+       /* Save the task's original addr_limit and set USER_DS (TASK_SIZE_64) */
+       ldr     x20, [tsk, #TI_ADDR_LIMIT]
+       str     x20, [sp, #S_ORIG_ADDR_LIMIT]
+       mov     x20, #TASK_SIZE_64
+       str     x20, [tsk, #TI_ADDR_LIMIT]
+       .endif /* \el == 0 */
        mrs     x22, elr_el1
        mrs     x23, spsr_el1
        stp     lr, x21, [sp, #S_LR]
@@ -128,6 +135,12 @@
        .endm
 
        .macro  kernel_exit, el
+       .if     \el != 0
+       /* Restore the task's original addr_limit. */
+       ldr     x20, [sp, #S_ORIG_ADDR_LIMIT]
+       str     x20, [tsk, #TI_ADDR_LIMIT]
+       .endif
+
        ldp     x21, x22, [sp, #S_PC]           // load ELR, SPSR
        .if     \el == 0
        ct_user_enter