diff mbox series

[02/28] staging: android: ion: use vmap instead of vm_map_ram

Message ID 20200408115926.1467567-3-hch@lst.de
State Not Applicable
Delegated to: David Miller
Headers show
Series [01/28] x86/hyperv: use vmalloc_exec for the hypercall page | expand

Commit Message

Christoph Hellwig April 8, 2020, 11:59 a.m. UTC 
vm_map_ram can keep mappings around after the vm_unmap_ram.  Using that
with non-PAGE_KERNEL mappings can lead to all kinds of aliasing issues.

Signed-off-by: Christoph Hellwig <hch@lst.de>
---
 drivers/staging/android/ion/ion_heap.c | 4 ++--
 1 file changed, 2 insertions(+), 2 deletions(-)

Comments

Greg KH April 8, 2020, 1:27 p.m. UTC | #1 
On Wed, Apr 08, 2020 at 01:59:00PM +0200, Christoph Hellwig wrote:
> vm_map_ram can keep mappings around after the vm_unmap_ram.  Using that
> with non-PAGE_KERNEL mappings can lead to all kinds of aliasing issues.
> 
> Signed-off-by: Christoph Hellwig <hch@lst.de>

Acked-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
diff mbox series

Patch

diff --git a/drivers/staging/android/ion/ion_heap.c b/drivers/staging/android/ion/ion_heap.c
index 473b465724f1..a2d5c6df4b96 100644
--- a/drivers/staging/android/ion/ion_heap.c
+++ b/drivers/staging/android/ion/ion_heap.c
@@ -99,12 +99,12 @@  int ion_heap_map_user(struct ion_heap *heap, struct ion_buffer *buffer,
 
 static int ion_heap_clear_pages(struct page **pages, int num, pgprot_t pgprot)
 {
-	void *addr = vm_map_ram(pages, num, -1, pgprot);
+	void *addr = vmap(pages, num, VM_MAP);
 
 	if (!addr)
 		return -ENOMEM;
 	memset(addr, 0, PAGE_SIZE * num);
-	vm_unmap_ram(addr, num);
+	vunmap(addr);
 
 	return 0;
 }