We can see following error when we run `findsym` on CLHSDB which connects to
remote debug server.
hsdb> verbose true
hsdb> findsym gHotSpotVMTypes
0x00007f913d4a45b0Error: java.lang.NullPointerException: Cannot invoke
"sun.jvm.hotspot.debugger.cdbg.CDebugger.loadObjectContainingPC(sun.jvm.hotspot.debugger.Address)"
because "cdbg" is null
java.lang.NullPointerException: Cannot invoke
"sun.jvm.hotspot.debugger.cdbg.CDebugger.loadObjectContainingPC(sun.jvm.hotspot.debugger.Address)"
because "cdbg" is null
at
jdk.hotspot.agent/sun.jvm.hotspot.CommandProcessor$7.doit(CommandProcessor.java:618)
at
jdk.hotspot.agent/sun.jvm.hotspot.CommandProcessor.executeCommand(CommandProcessor.java:2116)
at
jdk.hotspot.agent/sun.jvm.hotspot.CommandProcessor.executeCommand(CommandProcessor.java:2086)
at
jdk.hotspot.agent/sun.jvm.hotspot.CommandProcessor.run(CommandProcessor.java:1957)
at jdk.hotspot.agent/sun.jvm.hotspot.CLHSDB.run(CLHSDB.java:112)
at jdk.hotspot.agent/sun.jvm.hotspot.CLHSDB.main(CLHSDB.java:44)
at
jdk.hotspot.agent/sun.jvm.hotspot.SALauncher.runCLHSDB(SALauncher.java:282)
at
jdk.hotspot.agent/sun.jvm.hotspot.SALauncher.main(SALauncher.java:493)
The cause of this NPE is that CDebugger is null. It happens when the debugger
is running on debugd server.
Command line debugger like CLHSDB can delegate the command to debugd, like
`pmap` and `pstack`. `findsym` can also use this scheme.
This PR has passed serviceability/sa tests on Linux x64.
-------------
Commit messages:
- 8265505: findsym does not work on remote debug server
Changes: https://git.openjdk.java.net/jdk/pull/3582/files
Webrev: https://webrevs.openjdk.java.net/?repo=jdk&pr=3582&range=00
Issue: https://bugs.openjdk.java.net/browse/JDK-8265505
Stats: 92 lines in 6 files changed: 44 ins; 28 del; 20 mod
Patch: https://git.openjdk.java.net/jdk/pull/3582.diff
Fetch: git fetch https://git.openjdk.java.net/jdk pull/3582/head:pull/3582
PR: https://git.openjdk.java.net/jdk/pull/3582
