x86: warn about RAM pages in ioremap()

[sfrench/cifs-2.6.git] / arch / x86 / mm / ioremap.c

diff --git a/arch/x86/mm/ioremap.c b/arch/x86/mm/ioremap.c
index 4afaba0ed72221175854a856d347179b1ab3e979..3d0a589d92c40ebcf33882bf9d1b331894953037 100644 (file)
--- a/arch/x86/mm/ioremap.c
+++ b/arch/x86/mm/ioremap.c
@@ -35,6 +35,18 @@ unsigned long __phys_addr(unsigned long x)
 }
 EXPORT_SYMBOL(__phys_addr);
 
+static inline int phys_addr_valid(unsigned long addr)
+{
+       return addr < (1UL << boot_cpu_data.x86_phys_bits);
+}
+
+#else
+
+static inline int phys_addr_valid(unsigned long addr)
+{
+       return 1;
+}
+
 #endif
 
 int page_is_ram(unsigned long pagenr)
@@ -118,6 +130,13 @@ static void __iomem *__ioremap(resource_size_t phys_addr, unsigned long size,
        if (!size || last_addr < phys_addr)
                return NULL;
 
+       if (!phys_addr_valid(phys_addr)) {
+               printk(KERN_WARNING "ioremap: invalid physical address %lx\n",
+                      phys_addr);
+               WARN_ON_ONCE(1);
+               return NULL;
+       }
+
        /*
         * Don't remap the low PCI/ISA area, it's always mapped..
         */
@@ -127,17 +146,24 @@ static void __iomem *__ioremap(resource_size_t phys_addr, unsigned long size,
        /*
         * Don't allow anybody to remap normal RAM that we're using..
         */
-       for (pfn = phys_addr >> PAGE_SHIFT; pfn < max_pfn_mapped &&
-            (pfn << PAGE_SHIFT) < last_addr; pfn++) {
-               if (page_is_ram(pfn) && pfn_valid(pfn) &&
-                   !PageReserved(pfn_to_page(pfn)))
+       for (pfn = phys_addr >> PAGE_SHIFT;
+                               (pfn << PAGE_SHIFT) < last_addr; pfn++) {
+
+               int is_ram = page_is_ram(pfn);
+
+               if (is_ram && pfn_valid(pfn) && !PageReserved(pfn_to_page(pfn)))
                        return NULL;
+               WARN_ON_ONCE(is_ram);
        }
 
        switch (mode) {
        case IOR_MODE_UNCACHED:
        default:
-               prot = PAGE_KERNEL_NOCACHE;
+               /*
+                * FIXME: we will use UC MINUS for now, as video fb drivers
+                * depend on it. Upcoming ioremap_wc() will fix this behavior.
+                */
+               prot = PAGE_KERNEL_UC_MINUS;
                break;
        case IOR_MODE_CACHED:
                prot = PAGE_KERNEL;
@@ -268,8 +294,8 @@ static int __init early_ioremap_debug_setup(char *str)
 early_param("early_ioremap_debug", early_ioremap_debug_setup);
 
 static __initdata int after_paging_init;
-static __initdata pte_t bm_pte[PAGE_SIZE/sizeof(pte_t)]
-                               __attribute__((aligned(PAGE_SIZE)));
+static pte_t bm_pte[PAGE_SIZE/sizeof(pte_t)]
+               __section(.bss.page_aligned);
 
 static inline pmd_t * __init early_ioremap_pmd(unsigned long addr)
 {