x86: check for ioremap() failure in copy_oldmem_page()

Add a check for ioremap() failure in copy_oldmem_page().
This patch also includes small coding style fixes.

Signed-off-by: Akinobu Mita <akinobu.mita@gmail.com>
Signed-off-by: Ingo Molnar <mingo@elte.hu>

diff --git a/arch/x86/kernel/crash_dump_64.c b/arch/x86/kernel/crash_dump_64.c
index 15e6c6b..280d6ef 100644 (file)
--- a/arch/x86/kernel/crash_dump_64.c
+++ b/arch/x86/kernel/crash_dump_64.c
@@ -33,14 +33,16 @@ ssize_t copy_oldmem_page(unsigned long pfn, char *buf,
                return 0;
 
        vaddr = ioremap(pfn << PAGE_SHIFT, PAGE_SIZE);
+       if (!vaddr)
+               return -ENOMEM;
 
        if (userbuf) {
-               if (copy_to_user(buf, (vaddr + offset), csize)) {
+               if (copy_to_user(buf, vaddr + offset, csize)) {
                        iounmap(vaddr);
                        return -EFAULT;
                }
        } else
-       memcpy(buf, (vaddr + offset), csize);
+               memcpy(buf, vaddr + offset, csize);
 
        iounmap(vaddr);
        return csize;