From: Vishal Moola (Oracle) <vishal.moola@gmail.com>
Date: Wed, 3 Sep 2025 18:59:21 +0000 (-0700)
Subject: virtio_balloon: stop calling page_address() in free_pages()
X-Git-Url: https://www.infradead.org/git/?a=commitdiff_plain;h=d75d36547d11aed7fc0502e14f243873fb9c5844;p=users%2Fhch%2Fmisc.git

virtio_balloon: stop calling page_address() in free_pages()

free_pages() should be used when we only have a virtual address.  We
should call __free_pages() directly on our page instead.

Link: https://lkml.kernel.org/r/20250903185921.1785167-8-vishal.moola@gmail.com
Signed-off-by: Vishal Moola (Oracle) <vishal.moola@gmail.com>
Acked-by: David Hildenbrand <david@redhat.com>
Acked-by: Michael S. Tsirkin <mst@redhat.com>
Acked-by: Mike Rapoport (Microsoft) <rppt@kernel.org>
Cc: Albert Ou <aou@eecs.berkeley.edu>
Cc: Andy Lutomirski <luto@kernel.org>
Cc: Catalin Marinas <catalin.marinas@arm.com>
Cc: Dave Hansen <dave.hansen@linux.intel.com>
Cc: Jens Axboe <axboe@kernel.dk>
Cc: Justin Sanders <justin@coraid.com>
Cc: Madhavan Srinivasan <maddy@linux.ibm.com>
Cc: Matthew Wilcox (Oracle) <willy@infradead.org>
Cc: Michael Ellerman <mpe@ellerman.id.au>
Cc: "Michael S. Tsirkin" <mst@redhat.com>
Cc: Palmer Dabbelt <palmer@dabbelt.com>
Cc: Paul Walmsley <paul.walmsley@sifive.com>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Ritesh Harjani (IBM) <ritesh.list@gmail.com>
Cc: SeongJae Park <sj@kernel.org>
Cc: Will Deacon <will@kernel.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
---

diff --git a/drivers/virtio/virtio_balloon.c b/drivers/virtio/virtio_balloon.c
index eae65136cdfb..7f3fd72678eb 100644
--- a/drivers/virtio/virtio_balloon.c
+++ b/drivers/virtio/virtio_balloon.c
@@ -488,8 +488,7 @@ static unsigned long return_free_pages_to_mm(struct virtio_balloon *vb,
 		page = balloon_page_pop(&vb->free_page_list);
 		if (!page)
 			break;
-		free_pages((unsigned long)page_address(page),
-			   VIRTIO_BALLOON_HINT_BLOCK_ORDER);
+		__free_pages(page, VIRTIO_BALLOON_HINT_BLOCK_ORDER);
 	}
 	vb->num_free_page_blocks -= num_returned;
 	spin_unlock_irq(&vb->free_page_list_lock);
@@ -719,8 +718,7 @@ static int get_free_page_and_send(struct virtio_balloon *vb)
 	if (vq->num_free > 1) {
 		err = virtqueue_add_inbuf(vq, &sg, 1, p, GFP_KERNEL);
 		if (unlikely(err)) {
-			free_pages((unsigned long)p,
-				   VIRTIO_BALLOON_HINT_BLOCK_ORDER);
+			__free_pages(page, VIRTIO_BALLOON_HINT_BLOCK_ORDER);
 			return err;
 		}
 		virtqueue_kick(vq);
@@ -733,7 +731,7 @@ static int get_free_page_and_send(struct virtio_balloon *vb)
 		 * The vq has no available entry to add this page block, so
 		 * just free it.
 		 */
-		free_pages((unsigned long)p, VIRTIO_BALLOON_HINT_BLOCK_ORDER);
+		__free_pages(page, VIRTIO_BALLOON_HINT_BLOCK_ORDER);
 	}
 
 	return 0;