x86: fix virt_addr_valid() with CONFIG_DEBUG_VIRTUAL=y, v2

virt_addr_valid() calls __pa(), which calls __phys_addr(). With
CONFIG_DEBUG_VIRTUAL=y, __phys_addr() will kill the kernel if the
address *isn't* valid. That's clearly wrong for virt_addr_valid().

We also incorporate the debugging checks into virt_addr_valid().

Signed-off-by: Vegard Nossum <vegardno@ben.ifi.uio.no>
Acked-by: Jiri Slaby <jirislaby@gmail.com>
Signed-off-by: Ingo Molnar <mingo@elte.hu>

1 files changed, 7 insertions, 1 deletions

diff --git a/include/asm-x86/page.h b/include/asm-x86/page.h
index c91574776751..d4f1d5791fc1 100644
--- a/include/asm-x86/page.h
+++ b/include/asm-x86/page.h
@@ -179,6 +179,7 @@ static inline pteval_t native_pte_flags(pte_t pte)
 #endif  /* CONFIG_PARAVIRT */
 
 #define __pa(x)         __phys_addr((unsigned long)(x))
+#define __pa_nodebug(x) __phys_addr_nodebug((unsigned long)(x))
 /* __pa_symbol should be used for C visible symbols.
    This seems to be the official gcc blessed way to do such arithmetic. */
 #define __pa_symbol(x)  __pa(__phys_reloc_hide((unsigned long)(x)))
@@ -188,9 +189,14 @@ static inline pteval_t native_pte_flags(pte_t pte)
 #define __boot_va(x)            __va(x)
 #define __boot_pa(x)            __pa(x)
 
+/*
+ * virt_to_page(kaddr) returns a valid pointer if and only if
+ * virt_addr_valid(kaddr) returns true.
+ */
 #define virt_to_page(kaddr)     pfn_to_page(__pa(kaddr) >> PAGE_SHIFT)
 #define pfn_to_kaddr(pfn)      __va((pfn) << PAGE_SHIFT)
-#define virt_addr_valid(kaddr)  pfn_valid(__pa(kaddr) >> PAGE_SHIFT)
+extern bool __virt_addr_valid(unsigned long kaddr);
+#define virt_addr_valid(kaddr)  __virt_addr_valid((unsigned long) (kaddr))
 
 #endif  /* __ASSEMBLY__ */