x86: add debug warnings to early_ioremap()

Signed-off-by: Ingo Molnar <mingo@elte.hu>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>

diff --git a/arch/x86/mm/ioremap_32.c b/arch/x86/mm/ioremap_32.c
index 63f76ec..4bcd5e0 100644 (file)
--- a/arch/x86/mm/ioremap_32.c
+++ b/arch/x86/mm/ioremap_32.c
@@ -306,12 +306,15 @@ void __init *early_ioremap(unsigned long phys_addr, unsigned long size)
 
        /* Don't allow wraparound or zero size */
        last_addr = phys_addr + size - 1;
-       if (!size || last_addr < phys_addr)
+       if (!size || last_addr < phys_addr) {
+               WARN_ON(1);
                return NULL;
+       }
 
-       if (nesting >= FIX_BTMAPS_NESTING)
+       if (nesting >= FIX_BTMAPS_NESTING) {
+               WARN_ON(1);
                return NULL;
-
+       }
        early_ioremap_nested++;
        /*
         * Mappings have to be page-aligned
@@ -324,8 +327,10 @@ void __init *early_ioremap(unsigned long phys_addr, unsigned long size)
         * Mappings have to fit in the FIX_BTMAP area.
         */
        nrpages = size >> PAGE_SHIFT;
-       if (nrpages > NR_FIX_BTMAPS)
+       if (nrpages > NR_FIX_BTMAPS) {
+               WARN_ON(1);
                return NULL;
+       }
 
        /*
         * Ok, go for it..
@@ -351,11 +356,13 @@ void __init early_iounmap(void *addr, unsigned long size)
        unsigned int nesting;
 
        nesting = --early_ioremap_nested;
+       WARN_ON(nesting < 0);
 
        virt_addr = (unsigned long)addr;
-       if (virt_addr < fix_to_virt(FIX_BTMAP_BEGIN))
+       if (virt_addr < fix_to_virt(FIX_BTMAP_BEGIN)) {
+               WARN_ON(1);
                return;
-
+       }
        offset = virt_addr & ~PAGE_MASK;
        nrpages = PAGE_ALIGN(offset + size - 1) >> PAGE_SHIFT;