[PATCH 4.4] x86/kaiser: fix build error with KASAN && !FUNCTION_GRAPH_TRACER

[Eric Biggers <ebiggers@xxxxxxxxxx>]

This is a build fix for the 4.4 PTI backport.  4.4 kernels do not have
commit be7635e7287e ("arch, ftrace: for KASAN put hard/soft IRQ entries
into separate sections") which went into 4.6.  Consequently, the
irqentry sections are only created when CONFIG_FUNCTION_GRAPH_TRACER is
enabled, not also when CONFIG_KASAN is enabled.  Therefore, fix the
condition for trying to add a user mapping for this section.

This fixes the following build error:

    arch/x86/mm/kaiser.c: In function ‘kaiser_init’:
    arch/x86/mm/kaiser.c:367:33: error: ‘__irqentry_text_start’ undeclared (first use in this function)
      kaiser_add_user_map_ptrs_early(__irqentry_text_start,
    [...]

Signed-off-by: Eric Biggers <ebiggers@xxxxxxxxxx>
---
 arch/x86/mm/kaiser.c | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/arch/x86/mm/kaiser.c b/arch/x86/mm/kaiser.c
index 2298434f7bdb..7a72e32e4806 100644
--- a/arch/x86/mm/kaiser.c
+++ b/arch/x86/mm/kaiser.c
@@ -363,7 +363,7 @@ void __init kaiser_init(void)
 	kaiser_add_user_map_ptrs_early(__entry_text_start, __entry_text_end,
 				       __PAGE_KERNEL_RX);
 
-#if defined(CONFIG_FUNCTION_GRAPH_TRACER) || defined(CONFIG_KASAN)
+#ifdef CONFIG_FUNCTION_GRAPH_TRACER
 	kaiser_add_user_map_ptrs_early(__irqentry_text_start,
 				       __irqentry_text_end,
 				       __PAGE_KERNEL_RX);
-- 
2.16.0.rc1.238.g530d649a79-goog