#include <linux/device.h>
 #include <linux/poll.h>
 #include <linux/mutex.h>
+#include <linux/smp_lock.h>
 
 #include <asm/uaccess.h>
 #include <asm/atomic.h>
        eerb = kzalloc(sizeof(struct eerbuffer), GFP_KERNEL);
        if (!eerb)
                return -ENOMEM;
+       lock_kernel();
        eerb->buffer_page_count = eer_pages;
        if (eerb->buffer_page_count < 1 ||
            eerb->buffer_page_count > INT_MAX / PAGE_SIZE) {
                MESSAGE(KERN_WARNING, "can't open device since module "
                        "parameter eer_pages is smaller then 1 or"
                        " bigger then %d", (int)(INT_MAX / PAGE_SIZE));
+               unlock_kernel();
                return -EINVAL;
        }
        eerb->buffersize = eerb->buffer_page_count * PAGE_SIZE;
                               GFP_KERNEL);
         if (!eerb->buffer) {
                kfree(eerb);
+               unlock_kernel();
                 return -ENOMEM;
        }
        if (dasd_eer_allocate_buffer_pages(eerb->buffer,
                                           eerb->buffer_page_count)) {
                kfree(eerb->buffer);
                kfree(eerb);
+               unlock_kernel();
                return -ENOMEM;
        }
        filp->private_data = eerb;
        list_add(&eerb->list, &bufferlist);
        spin_unlock_irqrestore(&bufferlock, flags);
 
+       unlock_kernel();
        return nonseekable_open(inp,filp);
 }