diff --git a/.travis.yml b/.travis.yml
index ad576f1..eec8a02 100644
--- a/.travis.yml
+++ b/.travis.yml
@@ -26,9 +26,9 @@
     env: TOXENV=py37
   - python: "3.8"
     env: TOXENV=py38
-  - python: "pypy2.7-5.10.0"
+  - python: "pypy2.7-7.3.1"
     env: TOXENV=pypy
-  - python: "pypy3.5-5.10.1"
+  - python: "pypy3.6-7.3.1"
     env: TOXENV=pypy3
 
   # Also run the tests against cryptography master.
@@ -42,9 +42,9 @@
     env: TOXENV=py37-cryptographyMaster
   - python: "3.8"
     env: TOXENV=py38-cryptographyMaster
-  - python: "pypy2.7-5.10.0"
+  - python: "pypy2.7-7.3.1"
     env: TOXENV=pypy-cryptographyMaster
-  - python: "pypy3.5-5.10.1"
+  - python: "pypy3.6-7.3.1"
     env: TOXENV=pypy3-cryptographyMaster
 
   # And current minimum cryptography version.
@@ -58,9 +58,9 @@
     env: TOXENV=py37-cryptographyMinimum
   - python: "3.8"
     env: TOXENV=py38-cryptographyMinimum
-  - python: "pypy2.7-5.10.0"
+  - python: "pypy2.7-7.3.1"
     env: TOXENV=pypy-cryptographyMinimum
-  - python: "pypy3.5-5.10.1"
+  - python: "pypy3.6-7.3.1"
     env: TOXENV=pypy3-cryptographyMinimum
 
   # Run tests in random order
diff --git a/src/OpenSSL/_util.py b/src/OpenSSL/_util.py
index 1beefe6..d04244c 100644
--- a/src/OpenSSL/_util.py
+++ b/src/OpenSSL/_util.py
@@ -155,15 +155,4 @@
     return obj
 
 
-try:
-    # newer versions of cffi free the buffer deterministically
-    with ffi.from_buffer(b""):
-        pass
-    from_buffer = ffi.from_buffer
-except AttributeError:
-    # cffi < 0.12 frees the buffer with refcounting gc
-    from contextlib import contextmanager
-
-    @contextmanager
-    def from_buffer(*args):
-        yield ffi.from_buffer(*args)
+from_buffer = ffi.from_buffer