Introduce is_vmalloc_or_module_addr() and use with DEBUG_VIRTUAL
Impact: crash on module insertion with CONFIG_DEBUG_VIRTUAL
We would incorrectly BUG due to:
VIRTUAL_BUG_ON(!is_vmalloc_addr(vmalloc_addr) &&
!is_module_address(addr));
... because, at least on x86-64, is_module_address() doesn't do what
it should. This patch introduces is_vmalloc_or_module_addr(), which
is what we really want anyway, and uses it instead.
Signed-off-by: H. Peter Anvin <hpa@zytor.com>
diff --git a/mm/vmalloc.c b/mm/vmalloc.c
index bba06c4..f018d7e 100644
--- a/mm/vmalloc.c
+++ b/mm/vmalloc.c
@@ -168,6 +168,21 @@
}
EXPORT_SYMBOL_GPL(map_vm_area);
+static inline int is_vmalloc_or_module_addr(const void *x)
+{
+ /*
+ * x86-64 and sparc64 put modules in a special place,
+ * and fall back on vmalloc() if that fails. Others
+ * just put it in the vmalloc space.
+ */
+#if defined(CONFIG_MODULES) && defined(MODULES_VADDR)
+ unsigned long addr = (unsigned long)x;
+ if (addr >= MODULES_VADDR && addr < MODULES_END)
+ return 1;
+#endif
+ return is_vmalloc_addr(x);
+}
+
/*
* Map a vmalloc()-space virtual address to the physical page.
*/
@@ -184,8 +199,7 @@
* XXX we might need to change this if we add VIRTUAL_BUG_ON for
* architectures that do not vmalloc module space
*/
- VIRTUAL_BUG_ON(!is_vmalloc_addr(vmalloc_addr) &&
- !is_module_address(addr));
+ VIRTUAL_BUG_ON(!is_vmalloc_or_module_addr(vmalloc_addr));
if (!pgd_none(*pgd)) {
pud = pud_offset(pgd, addr);