[ARM] VFP: fix section mismatch error

Fix a real section mismatch issue; the test code is thrown away after
initialisation, but if we do not detect the VFP hardware, it is left
hooked into the exception handler.  Any VFP instructions which are
subsequently executed risk calling the discarded exception handler.

Introduce a new "null" handler which returns to the "unrecognised
fault" return address.

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

2 files changed, 8 insertions, 1 deletions

diff --git a/arch/arm/vfp/entry.S b/arch/arm/vfp/entry.S
index ca2a5ad19ea6..806ce26d5243 100644
--- a/arch/arm/vfp/entry.S
+++ b/arch/arm/vfp/entry.S
@@ -29,6 +29,10 @@ do_vfp:
         add     r10, r10, #TI_VFPSTATE  @ r10 = workspace
         ldr     pc, [r4]                @ call VFP entry point
 
+ENTRY(vfp_null_entry)
+        mov     pc, lr
+ENDPROC(vfp_null_entry)
+
 .LCvfp:
         .word   vfp_vector
 
diff --git a/arch/arm/vfp/vfpmodule.c b/arch/arm/vfp/vfpmodule.c
index f1e5951dc721..1106b5f9cf19 100644
--- a/arch/arm/vfp/vfpmodule.c
+++ b/arch/arm/vfp/vfpmodule.c
@@ -26,8 +26,9 @@
  */
 void vfp_testing_entry(void);
 void vfp_support_entry(void);
+void vfp_null_entry(void);
 
-void (*vfp_vector)(void) = vfp_testing_entry;
+void (*vfp_vector)(void) = vfp_null_entry;
 union vfp_state *last_VFP_context[NR_CPUS];
 
 /*
@@ -321,8 +322,10 @@ static int __init vfp_init(void)
          * The handler is already setup to just log calls, so
          * we just need to read the VFPSID register.
          */
+        vfp_vector = vfp_testing_entry;
         vfpsid = fmrx(FPSID);
         barrier();
+        vfp_vector = vfp_null_entry;
 
         printk(KERN_INFO "VFP support v0.3: ");
         if (VFP_arch) {