x86-32: make sure virt_addr_valid() returns false for fixmap addresses

I found that virt_addr_valid() was returning true for fixmap addresses.

I'm not sure whether pfn_valid() is supposed to include this test,
but there's no harm in being explicit.

Signed-off-by: Jeremy Fitzhardinge <jeremy.fitzhardinge@citrix.com>
Cc: Jiri Slaby <jirislaby@gmail.com>
Cc: Yinghai Lu <yinghai@kernel.org>
LKML-Reference: <49B166D6.2080505@goop.org>
Signed-off-by: Ingo Molnar <mingo@elte.hu>

1 files changed, 2 insertions, 0 deletions

diff --git a/arch/x86/mm/ioremap.c b/arch/x86/mm/ioremap.c
index 62773abdf088..62def5795730 100644
--- a/arch/x86/mm/ioremap.c
+++ b/arch/x86/mm/ioremap.c
@@ -87,6 +87,8 @@ bool __virt_addr_valid(unsigned long x)
                 return false;
         if (__vmalloc_start_set && is_vmalloc_addr((void *) x))
                 return false;
+        if (x >= FIXADDR_START)
+                return false;
         return pfn_valid((x - PAGE_OFFSET) >> PAGE_SHIFT);
 }
 EXPORT_SYMBOL(__virt_addr_valid);