uacce: remove uacce_vma_fault

Fix NULL pointer error if removing uacce's parent module during app's
running. SIGBUS is already reported by do_page_fault, so uacce_vma_fault
is not needed. If providing vma_fault, vmf->page has to be filled as well,
required by __do_fault.

Reported-by: Jean-Philippe Brucker <jean-philippe@linaro.org>
Signed-off-by: Zhangfei Gao <zhangfei.gao@linaro.org>
Reviewed-by: Jean-Philippe Brucker <jean-philippe@linaro.org>
Link: https://lore.kernel.org/r/1592229357-1904-1-git-send-email-zhangfei.gao@linaro.org
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

diff --git a/drivers/misc/uacce/uacce.c b/drivers/misc/uacce/uacce.c
index 107028e..aa91f69 100644 (file)
--- a/drivers/misc/uacce/uacce.c
+++ b/drivers/misc/uacce/uacce.c
@@ -179,14 +179,6 @@ static int uacce_fops_release(struct inode *inode, struct file *filep)
        return 0;
 }
 
-static vm_fault_t uacce_vma_fault(struct vm_fault *vmf)
-{
-       if (vmf->flags & (FAULT_FLAG_MKWRITE | FAULT_FLAG_WRITE))
-               return VM_FAULT_SIGBUS;
-
-       return 0;
-}
-
 static void uacce_vma_close(struct vm_area_struct *vma)
 {
        struct uacce_queue *q = vma->vm_private_data;
@@ -199,7 +191,6 @@ static void uacce_vma_close(struct vm_area_struct *vma)
 }
 
 static const struct vm_operations_struct uacce_vm_ops = {
-       .fault = uacce_vma_fault,
        .close = uacce_vma_close,
 };