exec: move rcu_read_lock/unlock to address_space_translate callers
Once address_space_translate will be called outside the BQL, the returned
MemoryRegion might disappear as soon as the RCU read-side critical section
ends. Avoid this by moving the critical section to the callers.
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
Message-Id: <1426684909-95030-3-git-send-email-pbonzini@redhat.com>
diff --git a/hw/vfio/common.c b/hw/vfio/common.c
index b012620..b1045da 100644
--- a/hw/vfio/common.c
+++ b/hw/vfio/common.c
@@ -270,13 +270,14 @@
* this IOMMU to its immediate target. We need to translate
* it the rest of the way through to memory.
*/
+ rcu_read_lock();
mr = address_space_translate(&address_space_memory,
iotlb->translated_addr,
&xlat, &len, iotlb->perm & IOMMU_WO);
if (!memory_region_is_ram(mr)) {
error_report("iommu map to non memory area %"HWADDR_PRIx"",
xlat);
- return;
+ goto out;
}
/*
* Translation truncates length to the IOMMU page size,
@@ -284,7 +285,7 @@
*/
if (len & iotlb->addr_mask) {
error_report("iommu has granularity incompatible with target AS");
- return;
+ goto out;
}
if ((iotlb->perm & IOMMU_RW) != IOMMU_NONE) {
@@ -307,6 +308,8 @@
iotlb->addr_mask + 1, ret);
}
}
+out:
+ rcu_read_unlock();
}
static void vfio_listener_region_add(MemoryListener *listener,
