1 files changed, 2 insertions, 2 deletions
diff --git a/drivers/char/mem.c b/drivers/char/mem.c
index 4f1813e04754..f5c160caf9f4 100644
--- a/drivers/char/mem.c
+++ b/drivers/char/mem.c
@@ -293,8 +293,8 @@ static int mmap_kmem(struct file * file, struct vm_area_struct * vma)
 {
        unsigned long pfn;
-        /* Turn a pfn offset into an absolute pfn */
+        /* Turn a kernel-virtual address into a physical page frame */
-        pfn = PFN_DOWN(virt_to_phys((void *)PAGE_OFFSET)) + vma->vm_pgoff;
+        pfn = __pa((u64)vma->vm_pgoff << PAGE_SHIFT) >> PAGE_SHIFT;
        /*
         * RED-PEN: on some architectures there is more mapped memory

diff --git a/drivers/char/mem.c b/drivers/char/mem.c index 4f1813e04754..f5c160caf9f4 100644 --- a/drivers/char/mem.c +++ b/drivers/char/mem.c
@@ -293,8 +293,8 @@ static int mmap_kmem(struct file * file, struct vm_area_struct * vma)
293	{	293	{
294	unsigned long pfn;	294	unsigned long pfn;
295		295
296	/* Turn a pfn offset into an absolute pfn */	296	/* Turn a kernel-virtual address into a physical page frame */
297	pfn = PFN_DOWN(virt_to_phys((void *)PAGE_OFFSET)) + vma->vm_pgoff;	297	pfn = __pa((u64)vma->vm_pgoff << PAGE_SHIFT) >> PAGE_SHIFT;
298		298
299	/*	299	/*
300	* RED-PEN: on some architectures there is more mapped memory	300	* RED-PEN: on some architectures there is more mapped memory