bpfloader: remove things already enforced by networking bpf loader am: 50fdc95894 am: e8c2a76dde am: ac228f0824 am: f7603192f1

Original change: https://android-review.googlesource.com/c/platform/system/bpf/+/2777983

Change-Id: I1daad52aac0abff9ae84a0db979d9faeac61b3b9
Signed-off-by: Automerger Merge Worker <android-build-automerger-merge-worker@system.gserviceaccount.com>
diff --git a/bpfloader/BpfLoader.cpp b/bpfloader/BpfLoader.cpp
index e3fde1e..8d8ae4f 100644
--- a/bpfloader/BpfLoader.cpp
+++ b/bpfloader/BpfLoader.cpp
@@ -180,42 +180,6 @@
     (void)argc;
     android::base::InitLogging(argv, &android::base::KernelLogger);
 
-    if (!android::bpf::isAtLeastKernelVersion(4, 19, 0)) {
-        ALOGE("Android U QPR2 requires kernel 4.19.");
-        return 1;
-    }
-
-    if (android::bpf::isUserspace32bit() && android::bpf::isAtLeastKernelVersion(6, 2, 0)) {
-        /* Android 14/U should only launch on 64-bit kernels
-         *   T launches on 5.10/5.15
-         *   U launches on 5.15/6.1
-         * So >=5.16 implies isKernel64Bit()
-         *
-         * We thus added a test to V VTS which requires 5.16+ devices to use 64-bit kernels.
-         *
-         * Starting with Android V, which is the first to support a post 6.1 Linux Kernel,
-         * we also require 64-bit userspace.
-         *
-         * There are various known issues with 32-bit userspace talking to various
-         * kernel interfaces (especially CAP_NET_ADMIN ones) on a 64-bit kernel.
-         * Some of these have userspace or kernel workarounds/hacks.
-         * Some of them don't...
-         * We're going to be removing the hacks.
-         *
-         * Additionally the 32-bit kernel jit support is poor,
-         * and 32-bit userspace on 64-bit kernel bpf ringbuffer compatibility is broken.
-         */
-        ALOGE("64-bit userspace required on 6.2+ kernels.");
-        return 1;
-    }
-
-    // Ensure we can determine the Android build type.
-    if (!android::bpf::isEng() && !android::bpf::isUser() && !android::bpf::isUserdebug()) {
-        ALOGE("Failed to determine the build type: got %s, want 'eng', 'user', or 'userdebug'",
-              android::bpf::getBuildType().c_str());
-        return 1;
-    }
-
     // Linux 5.16-rc1 changed the default to 2 (disabled but changeable), but we need 0 (enabled)
     // (this writeFile is known to fail on at least 4.19, but always defaults to 0 on pre-5.13,
     // on 5.13+ it depends on CONFIG_BPF_UNPRIV_DEFAULT_OFF)
@@ -263,14 +227,5 @@
         }
     }
 
-    int key = 1;
-    int value = 123;
-    android::base::unique_fd map(
-            android::bpf::createMap(BPF_MAP_TYPE_ARRAY, sizeof(key), sizeof(value), 2, 0));
-    if (android::bpf::writeToMapEntry(map, &key, &value, BPF_ANY)) {
-        ALOGE("Critical kernel bug - failure to write into index 1 of 2 element bpf map array.");
-        return 1;
-    }
-
     return 0;
 }