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>
diff --git a/arch/x86/mm/ioremap.c b/arch/x86/mm/ioremap.c
index 7fb737c..8876220 100644
--- a/arch/x86/mm/ioremap.c
+++ b/arch/x86/mm/ioremap.c
@@ -45,6 +45,27 @@
}
EXPORT_SYMBOL(__phys_addr);
+bool __virt_addr_valid(unsigned long x)
+{
+ if (x >= __START_KERNEL_map) {
+ x -= __START_KERNEL_map;
+ if (x >= KERNEL_IMAGE_SIZE)
+ return false;
+ x += phys_base;
+ } else {
+ if (x < PAGE_OFFSET)
+ return false;
+ x -= PAGE_OFFSET;
+ if (system_state == SYSTEM_BOOTING ?
+ x > MAXMEM : !phys_addr_valid(x)) {
+ return false;
+ }
+ }
+
+ return pfn_valid(x >> PAGE_SHIFT);
+}
+EXPORT_SYMBOL(__virt_addr_valid);
+
#else
static inline int phys_addr_valid(unsigned long addr)
@@ -56,13 +77,24 @@
unsigned long __phys_addr(unsigned long x)
{
/* VMALLOC_* aren't constants; not available at the boot time */
- VIRTUAL_BUG_ON(x < PAGE_OFFSET || (system_state != SYSTEM_BOOTING &&
- is_vmalloc_addr((void *)x)));
+ VIRTUAL_BUG_ON(x < PAGE_OFFSET);
+ VIRTUAL_BUG_ON(system_state != SYSTEM_BOOTING &&
+ is_vmalloc_addr((void *) x));
return x - PAGE_OFFSET;
}
EXPORT_SYMBOL(__phys_addr);
#endif
+bool __virt_addr_valid(unsigned long x)
+{
+ if (x < PAGE_OFFSET)
+ return false;
+ if (system_state != SYSTEM_BOOTING && is_vmalloc_addr((void *) x))
+ return false;
+ return pfn_valid((x - PAGE_OFFSET) >> PAGE_SHIFT);
+}
+EXPORT_SYMBOL(__virt_addr_valid);
+
#endif
int page_is_ram(unsigned long pagenr)