agent start fail

[kiwi9607]

/**
* Inject the classes into bootstrap class loader by using Unsafe Strategy.
* ByteBuddy adapts the sun.misc.Unsafe and jdk.internal.misc.Unsafe automatically.
*/
ClassInjector.UsingUnsafe.Factory factory = ClassInjector.UsingUnsafe.Factory.resolve(instrumentation);
factory.make(null, null).injectRaw(classesTypeMap);
agentBuilder = agentBuilder.with(new AgentBuilder.InjectionStrategy.UsingUnsafe.OfFactory(factory));

When using this code, the agent will encounter this error when starting up.
use jdk: IBM 7.2
Error message:

 (0x00007FD01BE375E7 [libjclse7b_26.so+0x1b5e7]) 

 Java_sun_misc_Unsafe_defineClass__Ljava_lang_String_2_3BIIJLjava_lang_ClassLoader_2Ljava_security_ProtectionDomain_2+0x36E76F46 ([libjclse7b_26.so+0x5af46]) 

 (0x00007FD023C6758F [libj9vm26.so+0x3358f]) 

 Unhandled exception Type=Segmentation error 
 Signal_Code=00000001
InaccessibleAddress=0x0000000000000000 

can you give me some help.

[wu-sheng]

Could you share a clearer context? e.g. your demo app, explicit JDK version(oss or commercial).

[kiwi9607]

  no demo. is project. jdk version:   java version "1.7.0" Java(TM) SE Runtime Environment (build pxa6470sr4fp1ifix-20130423_02(SR4 FP1+IV38579+IV38 IBM J9 VM (build 2.6, JRE 1.7.0 Linux amd64-64 Compressed References 20130421_145945  J9VM - R26_Java726_SR4_FP1_2_20130421_2353_B145945  R26_Java726_SR4_FP1_2_20130421_2353_B145945_CMPRSS JCL - 20130225_01 based on Oracle 7u13-b08

…

---Original--- From: "吴晟 Wu ***@***.***> Date: Thu, Sep 3, 2026 15:39 PM To: ***@***.***>; Cc: ***@***.******@***.***>; Subject: Re: [apache/skywalking] agent start fail (Discussion #14053) Could you share a clearer context? e.g. your demo app, explicit JDK version(oss or commercial). — Reply to this email directly, view it on GitHub, or unsubscribe. Triage notifications, keep track of coding agent tasks and review pull requests on the go with GitHub Mobile for iOS and Android. Download it today! You are receiving this because you authored the thread.Message ID: ***@***.***>

[wu-sheng]

If there is no project, we don't have much to do.
But at least, JDK 7 has not been supported for a very long time.

https://skywalking.apache.org/docs/skywalking-java/latest/en/setup/service-agent/java-agent/readme/

[kiwi9607]

Thanks! Our team has initially pinpointed the issue to the agent's enhancement of threads. Removing this instrumentation resolves the problem. It turns out there's a vulnerability in IBM JDK's defineClass implementation.

…

---Original--- From: "吴晟 Wu ***@***.***> Date: Thu, Sep 3, 2026 16:41 PM To: ***@***.***>; Cc: ***@***.******@***.***>; Subject: Re: [apache/skywalking] agent start fail (Discussion #14053) If there is no project, we don't have much to do. But at least, JDK 7 has not been supported for a very long time. https://skywalking.apache.org/docs/skywalking-java/latest/en/setup/service-agent/java-agent/readme/ — Reply to this email directly, view it on GitHub, or unsubscribe. Triage notifications, keep track of coding agent tasks and review pull requests on the go with GitHub Mobile for iOS and Android. Download it today! You are receiving this because you authored the thread.Message ID: ***@***.***>