x86-32: use specific __vmalloc_start_set flag in __virt_addr_valid

Rather than relying on the ever-unreliable system_state,
add a specific __vmalloc_start_set flag to indicate whether
the vmalloc area has meaningful boundaries yet, and use that
in x86-32's __phys_addr and __virt_addr_valid.

Signed-off-by: Jeremy Fitzhardinge <jeremy.fitzhardinge@citrix.com>
Signed-off-by: Ingo Molnar <mingo@elte.hu>

1 files changed, 4 insertions, 0 deletions

diff --git a/arch/x86/mm/init_32.c b/arch/x86/mm/init_32.c
index 5e5126e0d544..d57dfffb0213 100644
--- a/arch/x86/mm/init_32.c
+++ b/arch/x86/mm/init_32.c
@@ -59,6 +59,8 @@ unsigned long highstart_pfn, highend_pfn;
 
 static noinline int do_test_wp_bit(void);
 
+bool __read_mostly __vmalloc_start_set = false;
+
 static __init void *alloc_low_page(void)
 {
         unsigned long pfn = e820_table_end++;
@@ -757,6 +759,8 @@ void __init initmem_init(unsigned long start_pfn,
 #ifdef CONFIG_FLATMEM
         max_mapnr = num_physpages;
 #endif
+        __vmalloc_start_set = true;
+
         printk(KERN_NOTICE "%ldMB LOWMEM available.\n",
                         pages_to_mb(max_low_pfn));