[PATCH] drm/amd/amdgpu: fix offset into page with amdgpu_iomem debugfs file

[Tom St Denis]

The offset inside the page wasn't included in the copy call meaning
the start of the page was being read/written instead.

Reported-by: Jay Cornwall <Jay.Cornwall at amd.com>
Signed-off-by: Tom St Denis <tom.stdenis at amd.com>
---
 drivers/gpu/drm/amd/amdgpu/amdgpu_ttm.c | 4 ++--
 1 file changed, 2 insertions(+), 2 deletions(-)

diff --git a/drivers/gpu/drm/amd/amdgpu/amdgpu_ttm.c b/drivers/gpu/drm/amd/amdgpu/amdgpu_ttm.c
index 291dd3d600cd..d2ab40494a4c 100644
--- a/drivers/gpu/drm/amd/amdgpu/amdgpu_ttm.c
+++ b/drivers/gpu/drm/amd/amdgpu/amdgpu_ttm.c
@@ -1996,7 +1996,7 @@ static ssize_t amdgpu_iomem_read(struct file *f, char __user *buf,
 			return -EPERM;
 
 		ptr = kmap(p);
-		r = copy_to_user(buf, ptr, bytes);
+		r = copy_to_user(buf, ptr + off, bytes);
 		kunmap(p);
 		if (r)
 			return -EFAULT;
@@ -2040,7 +2040,7 @@ static ssize_t amdgpu_iomem_write(struct file *f, const char __user *buf,
 			return -EPERM;
 
 		ptr = kmap(p);
-		r = copy_from_user(ptr, buf, bytes);
+		r = copy_from_user(ptr + off, buf, bytes);
 		kunmap(p);
 		if (r)
 			return -EFAULT;
-- 
2.14.3