commit 0b8e2c1002afddc8ef3d52fa6fc29e4768429f98
author Peter Maydell <peter.maydell@linaro.org> Mon Jul 20 12:27:16 2015 +0100
committer Paolo Bonzini <pbonzini@redhat.com> Thu Jul 23 07:37:38 2015 +0200
tree 9b8bb89a039327032c84e624a726fe3633b318c7
parent dc94bd9166af5236a56bd5bb06845911915a925c

exec.c: Use atomic_rcu_read() to access dispatch in memory_region_section_get_iotlb()

When accessing the dispatch pointer in an AddressSpace within an RCU
critical section we should always use atomic_rcu_read(). Fix an
access within memory_region_section_get_iotlb() which was incorrectly
doing a direct pointer access.

Signed-off-by: Peter Maydell <peter.maydell@linaro.org>
Message-Id: <1437391637-31576-1-git-send-email-peter.maydell@linaro.org>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>

exec.c

diff --git a/exec.c b/exec.c
index 7d60e15..0a4a0c5 100644
--- a/exec.c
+++ b/exec.c
@@ -954,7 +954,10 @@
             iotlb |= PHYS_SECTION_ROM;
         }
     } else {
-        iotlb = section - section->address_space->dispatch->map.sections;
+        AddressSpaceDispatch *d;
+
+        d = atomic_rcu_read(&section->address_space->dispatch);
+        iotlb = section - d->map.sections;
         iotlb += xlat;
     }