Henry Robinson created HDFS-11851: ------------------------------------- Summary: getGlobalJNIEnv() may deadlock if exception is thrown Key: HDFS-11851 URL: https://issues.apache.org/jira/browse/HDFS-11851 Project: Hadoop HDFS Issue Type: Bug Components: libhdfs Reporter: Henry Robinson Priority: Blocker
HDFS-11529 introduced a deadlock into {{getGlobalJNIEnv()}} if an exception is thrown. {{getGlobalJNIEnv()}} holds {{jvmMutex}}, but {{printExceptionAndFree()}} will eventually try to acquire that lock in {{setTLSExceptionStrings()}}. The exception might get caught from {{loadFileSystems}}: {code} jthr = invokeMethod(env, NULL, STATIC, NULL, "org/apache/hadoop/fs/FileSystem", "loadFileSystems", "()V"); if (jthr) { printExceptionAndFree(env, jthr, PRINT_EXC_ALL, "loadFileSystems"); } } {code} and here's the relevant parts of the stack trace from where I call this API in Impala, which uses {{libhdfs}}: {code} #0 __lll_lock_wait () at ../nptl/sysdeps/unix/sysv/linux/x86_64/lowlevellock.S:135 #1 0x00007ffff4a8d657 in _L_lock_909 () from /lib/x86_64-linux-gnu/libpthread.so.0 #2 0x00007ffff4a8d480 in __GI___pthread_mutex_lock (mutex=0x47ce960 <jvmMutex>) at ../nptl/pthread_mutex_lock.c:79 #3 0x0000000002f06056 in mutexLock (m=<optimized out>) at /data/2/jenkins/workspace/impala-hadoop-dependency/hadoop/hadoop-hdfs-project/hadoop-hdfs/src/main/native/libhdfs/os/posix/mutexes.c:28 #4 0x0000000002efe817 in setTLSExceptionStrings (rootCause=0x0, stackTrace=0x0) at /data/2/jenkins/workspace/impala-hadoop-dependency/hadoop/hadoop-hdfs-project/hadoop-hdfs/src/main/native/libhdfs/jni_helper.c:581 #5 0x0000000002f065d7 in printExceptionAndFreeV (env=0x513c1e8, exc=0x508a8c0, noPrintFlags=<optimized out>, fmt=0x34349cf "loadFileSystems", ap=0x7fffffffb660) at /data/2/jenkins/workspace/impala-hadoop-dependency/hadoop/hadoop-hdfs-project/hadoop-hdfs/src/main/native/libhdfs/exception.c:183 #6 0x0000000002f0683d in printExceptionAndFree (env=<optimized out>, exc=<optimized out>, noPrintFlags=<optimized out>, fmt=<optimized out>) at /data/2/jenkins/workspace/impala-hadoop-dependency/hadoop/hadoop-hdfs-project/hadoop-hdfs/src/main/native/libhdfs/exception.c:213 #7 0x0000000002eff60f in getGlobalJNIEnv () at /data/2/jenkins/workspace/impala-hadoop-dependency/hadoop/hadoop-hdfs-project/hadoop-hdfs/src/main/native/libhdfs/jni_helper.c:463 {code} -- This message was sent by Atlassian JIRA (v6.3.15#6346) --------------------------------------------------------------------- To unsubscribe, e-mail: hdfs-dev-unsubscr...@hadoop.apache.org For additional commands, e-mail: hdfs-dev-h...@hadoop.apache.org