RFR: 8376269: Mixed jstack cannot find function in vDSO [v4]

[Yasumasa Suenaga]

On Wed, 4 Feb 2026 12:17:16 GMT, Kevin Walls <kevinw at openjdk.org> wrote:

> Was it meant to pass strlen(lib_name)?

`lib_name` is allocated with `char[BUF_SIZE]`, and is used in subsequent code in `read_shared_lib_info()`, thus I want to overwrite it to real path of vDSO binary at `handle_vdso()`. Hence I passed buffer size, not length of string.

> Then handle_vdso checks /lib/modules... exists, and then opens it with pathmap_open? So it has to exist without pathmap, but may also be in the SA_ALTROOT directory.
Should handle_vdso also try pathmap_open() first?

Good catch! Fixed in new commit.

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PR Review Comment: https://git.openjdk.org/jdk/pull/29400#discussion_r2766618139