[PATCH v2 09/12] arch/x86: don't initialize kasan if it's disabled

[Baoquan He]

And also add code to enable kasan_flag_enabled, this is for later
usage.

Signed-off-by: Baoquan He <b...@redhat.com>
---
 arch/x86/mm/kasan_init_64.c | 6 ++++++
 1 file changed, 6 insertions(+)

diff --git a/arch/x86/mm/kasan_init_64.c b/arch/x86/mm/kasan_init_64.c
index 0539efd0d216..0f2f9311e9df 100644
--- a/arch/x86/mm/kasan_init_64.c
+++ b/arch/x86/mm/kasan_init_64.c
@@ -343,6 +343,9 @@ void __init kasan_init(void)
        unsigned long shadow_cea_begin, shadow_cea_per_cpu_begin, 
shadow_cea_end;
        int i;
 
+       if (kasan_arg_disabled)
+               return;
+
        memcpy(early_top_pgt, init_top_pgt, sizeof(early_top_pgt));
 
        /*
@@ -450,6 +453,9 @@ void __init kasan_init(void)
        /* Flush TLBs again to be sure that write protection applied. */
        __flush_tlb_all();
 
+       /* KASAN is now initialized, enable it. */
+       static_branch_enable(&kasan_flag_enabled);
+
        init_task.kasan_depth = 0;
        pr_info("KernelAddressSanitizer initialized\n");
 }
-- 
2.41.0