Add a helpful error message if GetUnreachableMemory fails
The primary reason for GetUnreachableMemory failing is selinux
blocking system apps from ptracing themselves. Add a helpful
error message suggesting setenforce 0.
Bug: 27945735
Test: dumpsys meminfo --unreachable com.android.systemui
Change-Id: Ibfa9507860be36dffd514f82027f7a2f8a72ac48
diff --git a/libmemunreachable/MemUnreachable.cpp b/libmemunreachable/MemUnreachable.cpp
index e7c0beb..1c84744 100644
--- a/libmemunreachable/MemUnreachable.cpp
+++ b/libmemunreachable/MemUnreachable.cpp
@@ -502,7 +502,10 @@
std::string GetUnreachableMemoryString(bool log_contents, size_t limit) {
UnreachableMemoryInfo info;
if (!GetUnreachableMemory(info, limit)) {
- return "Failed to get unreachable memory\n";
+ return "Failed to get unreachable memory\n"
+ "If you are trying to get unreachable memory from a system app\n"
+ "(like com.android.systemui), disable selinux first using\n"
+ "setenforce 0\n";
}
return info.ToString(log_contents);