[PATCH 03/29] staging: android: ion: use vmap instead of vm_map_ram

Christoph Hellwig hch at lst.de
Tue Apr 14 23:13:22 AEST 2020


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 at lst.de>
Acked-by: Greg Kroah-Hartman <gregkh at linuxfoundation.org>
Acked-by: Peter Zijlstra (Intel) <peterz at infradead.org>
---
 drivers/staging/android/ion/ion_heap.c | 4 ++--
 1 file changed, 2 insertions(+), 2 deletions(-)

diff --git a/drivers/staging/android/ion/ion_heap.c b/drivers/staging/android/ion/ion_heap.c
index 473b465724f1..0755b11348ed 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, pgprot);
 
 	if (!addr)
 		return -ENOMEM;
 	memset(addr, 0, PAGE_SIZE * num);
-	vm_unmap_ram(addr, num);
+	vunmap(addr);
 
 	return 0;
 }
-- 
2.25.1



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