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| author | Dmitry Torokhov <dmitry.torokhov@gmail.com> | 2010-05-19 10:12:41 -0700 |
|---|---|---|
| committer | Dmitry Torokhov <dmitry.torokhov@gmail.com> | 2010-05-19 10:12:41 -0700 |
| commit | 8d0bc2b456103a34c11e01305cd1aed1cde579e5 (patch) | |
| tree | 5e1e6ad55cc9e2b5c5617f6f320114b8cff9e3f3 /drivers/vhost/vhost.c | |
| parent | 30ba3ead05763b172acaa65ae1be71af2a878940 (diff) | |
| parent | e40152ee1e1c7a63f4777791863215e3faa37a86 (diff) | |
| download | linux-8d0bc2b456103a34c11e01305cd1aed1cde579e5.tar.bz2 | |
Merge commit 'v2.6.34' into next
Diffstat (limited to 'drivers/vhost/vhost.c')
| -rw-r--r-- | drivers/vhost/vhost.c | 11 |
1 files changed, 10 insertions, 1 deletions
diff --git a/drivers/vhost/vhost.c b/drivers/vhost/vhost.c index 5be11c99e18f..49fa953aaf6e 100644 --- a/drivers/vhost/vhost.c +++ b/drivers/vhost/vhost.c @@ -236,6 +236,10 @@ static int vq_memory_access_ok(void __user *log_base, struct vhost_memory *mem, int log_all) { int i; + + if (!mem) + return 0; + for (i = 0; i < mem->nregions; ++i) { struct vhost_memory_region *m = mem->regions + i; unsigned long a = m->userspace_addr; @@ -1031,7 +1035,12 @@ int vhost_add_used(struct vhost_virtqueue *vq, unsigned int head, int len) /* This actually signals the guest, using eventfd. */ void vhost_signal(struct vhost_dev *dev, struct vhost_virtqueue *vq) { - __u16 flags = 0; + __u16 flags; + /* Flush out used index updates. This is paired + * with the barrier that the Guest executes when enabling + * interrupts. */ + smp_mb(); + if (get_user(flags, &vq->avail->flags)) { vq_err(vq, "Failed to get flags"); return; |