ARM: move PC value into r9

Move the saved PC value into r9, thereby moving it into a caller-saved
register for functions that we may call during the entry to a syscall.

Signed-off-by: Russell King <rmk+kernel@armlinux.org.uk>

diff --git a/arch/arm/kernel/entry-common.S b/arch/arm/kernel/entry-common.S
index 374c287..1b3fc79 100644 (file)
--- a/arch/arm/kernel/entry-common.S
+++ b/arch/arm/kernel/entry-common.S
@@ -28,7 +28,13 @@
 #include "entry-header.S"
 
 saved_psr      .req    r8
+#if defined(CONFIG_TRACE_IRQFLAGS) || defined(CONFIG_CONTEXT_TRACKING)
+saved_pc       .req    r9
+#define TRACE(x...) x
+#else
 saved_pc       .req    lr
+#define TRACE(x...)
+#endif
 
        .align  5
 #if !(IS_ENABLED(CONFIG_TRACE_IRQFLAGS) || IS_ENABLED(CONFIG_CONTEXT_TRACKING))
@@ -144,6 +150,7 @@ ENTRY(vector_swi)
  THUMB(        mov     r8, sp                  )
  THUMB(        store_user_sp_lr r8, r10, S_SP  )       @ calling sp, lr
        mrs     saved_psr, spsr                 @ called from non-FIQ mode, so ok.
+ TRACE(        mov     saved_pc, lr            )
        str     saved_pc, [sp, #S_PC]           @ Save calling PC
        str     saved_psr, [sp, #S_PSR]         @ Save CPSR
        str     r0, [sp, #S_OLD_R0]             @ Save OLD_R0