On Thu, 5 Feb 2026 14:41:20 GMT, Yasumasa Suenaga <[email protected]> wrote:

>> Some functions / signal trampoline would be provided by vDSO in Linux. 
>> However SA cannot find symbols in it because it is not a regular ELF, it is 
>> on the memory only.
>> For example, mixed jstack could not decode the symbol in the coredump 
>> crashed in gettimeofday(2) as following:
>> 
>> 
>> 0x00007faae3dd0818      VMError::report_and_die(Thread*, unsigned int, 
>> unsigned char*, void const*, void const*) + 0x58
>> 0x00007faae3aff1ba      JVM_handle_linux_signal + 0x42a
>> 0x00007faae4ad9290      <signal handler called>
>> 0x00007faae4cd8e69              ????????
>> 0x00007faaca78ffa1      <nep_invoker_blob>
>> 0x00007faaca73fd48      * 
>> java.lang.invoke.LambdaForm$MH+0x0000000028156c00.invoke(java.lang.Object, 
>> long, long, long) bci:12 (Interpreted frame)
>> 
>> 
>> It should be:
>> 
>> 
>> 0x00007fb5841d0818      VMError::report_and_die(Thread*, unsigned int, 
>> unsigned char*, void const*, void const*) + 0x58
>> 0x00007fb583eff1ba      JVM_handle_linux_signal + 0x42a
>> 0x00007fb584fd9290      <signal handler called>
>> 0x00007fb5851d8e69      __cvdso_gettimeofday_data.constprop.0 + 0x99
>> 0x00007fb56a78f321      <nep_invoker_blob>
>> 0x00007fb56a73fd48      * 
>> java.lang.invoke.LambdaForm$MH+0x000000000e156c00.invoke(java.lang.Object, 
>> long, long, long) bci:12 (Interpreted frame)
>> 
>> 
>> Some platforms (Ubuntu 24.04 and Fedora 43 at least) provide vDSO binary in 
>> `/lib/modules/<kernel version>/vdso`. This patch attempts to load it if we 
>> can refer it because we want to use debuginfo of vDSO if possible. Otherwise 
>> load vDSO memory.
>
> Yasumasa Suenaga has updated the pull request incrementally with one 
> additional commit since the last revision:
> 
>   Skip TestJhsdbJstackMixedWithVDSOCallCore.java if it runs on musl libc

Skipping musl sounds good.

This is not text that is visible in the product, so not critical, but we should 
be careful with saying "not supported yet" as it sounds like a commitment to 
support something.   This is a message in a test and not a commitment about 
what might appear as a feature.

-------------

Marked as reviewed by kevinw (Reviewer).

PR Review: https://git.openjdk.org/jdk/pull/29400#pullrequestreview-3757613948

Reply via email to