From: Christoph Hellwig hch@lst.de

[ Upstream commit 5bf9917452112694b2c774465ee4dbe441c84b77 ]

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 Signed-off-by: Andrew Morton akpm@linux-foundation.org Acked-by: Greg Kroah-Hartman gregkh@linuxfoundation.org Acked-by: Peter Zijlstra (Intel) peterz@infradead.org Cc: Christian Borntraeger borntraeger@de.ibm.com Cc: Christophe Leroy christophe.leroy@c-s.fr Cc: Daniel Vetter daniel.vetter@ffwll.ch Cc: David Airlie airlied@linux.ie Cc: Gao Xiang xiang@kernel.org Cc: Haiyang Zhang haiyangz@microsoft.com Cc: Johannes Weiner hannes@cmpxchg.org Cc: "K. Y. Srinivasan" kys@microsoft.com Cc: Laura Abbott labbott@redhat.com Cc: Mark Rutland mark.rutland@arm.com Cc: Michael Kelley mikelley@microsoft.com Cc: Minchan Kim minchan@kernel.org Cc: Nitin Gupta ngupta@vflare.org Cc: Robin Murphy robin.murphy@arm.com Cc: Sakari Ailus sakari.ailus@linux.intel.com Cc: Stephen Hemminger sthemmin@microsoft.com Cc: Sumit Semwal sumit.semwal@linaro.org Cc: Wei Liu wei.liu@kernel.org Cc: Benjamin Herrenschmidt benh@kernel.crashing.org Cc: Catalin Marinas catalin.marinas@arm.com Cc: Heiko Carstens heiko.carstens@de.ibm.com Cc: Paul Mackerras paulus@ozlabs.org Cc: Vasily Gorbik gor@linux.ibm.com Cc: Will Deacon will@kernel.org Link: http://lkml.kernel.org/r/20200414131348.444715-4-hch@lst.de Signed-off-by: Linus Torvalds torvalds@linux-foundation.org Signed-off-by: Sasha Levin sashal@kernel.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 13a9b4c42b26..ae08b3253c21 100644 --- a/drivers/staging/android/ion/ion_heap.c +++ b/drivers/staging/android/ion/ion_heap.c @@ -105,12 +105,12 @@ 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; }