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| author | Anthony Liguori <aliguori@us.ibm.com> | 2008-08-18 22:15:31 (GMT) |
|---|---|---|
| committer | Rusty Russell <rusty@rustcorp.com.au> | 2008-08-25 14:19:25 (GMT) |
| commit | 532a6086e35fa3b5761e68af36d4e42a550eba15 (patch) | |
| tree | c1d8ab4df9db25e0efd89dab64dda98f84df1fa6 /drivers/virtio | |
| parent | 83097aca8567a0bd593534853b71fe0fa9a75d69 (diff) | |
| download | linux-532a6086e35fa3b5761e68af36d4e42a550eba15.tar.xz | |
virtio_balloon: fix towards_target when deflating balloon
Both v and vb->num_pages are u32 and unsigned int respectively. If v is less
than vb->num_pages (and it is, when deflating the balloon), the result is a
very large 32-bit number. Since we're returning a s64, instead of getting the
same negative number we desire, we get a very large positive number.
This handles the case where v < vb->num_pages and ensures we get a small,
negative, s64 as the result.
Rusty: please push this for 2.6.27-rc4. It's probably appropriate for the
stable tree too as it will cause an unexpected OOM when ballooning.
Signed-off-by: Anthony Liguori <aliguori@us.ibm.com>
Signed-off-by: Rusty Russell <rusty@rustcorp.com.au> (simplified)
Diffstat (limited to 'drivers/virtio')
| -rw-r--r-- | drivers/virtio/virtio_balloon.c | 2 |
1 files changed, 1 insertions, 1 deletions
diff --git a/drivers/virtio/virtio_balloon.c b/drivers/virtio/virtio_balloon.c index bfef604..62eab43 100644 --- a/drivers/virtio/virtio_balloon.c +++ b/drivers/virtio/virtio_balloon.c @@ -158,7 +158,7 @@ static inline s64 towards_target(struct virtio_balloon *vb) vb->vdev->config->get(vb->vdev, offsetof(struct virtio_balloon_config, num_pages), &v, sizeof(v)); - return v - vb->num_pages; + return (s64)v - vb->num_pages; } static void update_balloon_size(struct virtio_balloon *vb) |