Re: RFR: 8283849: AsyncGetCallTrace may crash JVM on guarantee [v4]
On Thu, 5 May 2022 13:02:58 GMT, Jaroslav Bachorik wrote: >> A gist of the fix is to allow relaxed special handling of code blob lookup >> when done for ASGCT. >> >> Currently, a guarantee will fail when we happen to hit a zombie method which >> is still on stack. While this would indicate a serious error for the normal >> execution flow, in case of ASGCT being in progress when the executing thread >> can be expected at any possible method this is something which may happen >> and we really should not take the profiled JVM down due to it. >> >> >> Unfortunately, I am not able to create a simple reproducer for the crash >> other that testing in our production where the crash is happening >> sporadically. >> However, thanks to @parttimenerd and his [ASGCT stress >> test](https://github.com/parttimenerd/asgct2-tester.git) the problem can be >> reproduced quite reliably. >> >> >> >> _Note: This is a followup PR for #8061_ > > Jaroslav Bachorik has updated the pull request incrementally with one > additional commit since the last revision: > > AGCT -> ASGCT > I would like to disagree: The abbreviation "ASGCT" is used in multiple places > in the JVM, > especially in `forte.cpp` (where "AGCT" cannot be found). That was a very old mistake on my part. It should have been `AGCT` instead of `ASGCT` and I never got around to fixing that. - PR: https://git.openjdk.java.net/jdk/pull/8549
Re: RFR: 8283849: AsyncGetCallTrace may crash JVM on guarantee [v4]
> A gist of the fix is to allow relaxed special handling of code blob lookup > when done for ASGCT. > > Currently, a guarantee will fail when we happen to hit a zombie method which > is still on stack. While this would indicate a serious error for the normal > execution flow, in case of ASGCT being in progress when the executing thread > can be expected at any possible method this is something which may happen and > we really should not take the profiled JVM down due to it. > > > Unfortunately, I am not able to create a simple reproducer for the crash > other that testing in our production where the crash is happening > sporadically. > However, thanks to @parttimenerd and his [ASGCT stress > test](https://github.com/parttimenerd/asgct2-tester.git) the problem can be > reproduced quite reliably. > > > > _Note: This is a followup PR for #8061_ Jaroslav Bachorik has updated the pull request incrementally with one additional commit since the last revision: AGCT -> ASGCT - Changes: - all: https://git.openjdk.java.net/jdk/pull/8549/files - new: https://git.openjdk.java.net/jdk/pull/8549/files/71e5a919..caf43e39 Webrevs: - full: https://webrevs.openjdk.java.net/?repo=jdk&pr=8549&range=03 - incr: https://webrevs.openjdk.java.net/?repo=jdk&pr=8549&range=02-03 Stats: 15 lines in 3 files changed: 4 ins; 8 del; 3 mod Patch: https://git.openjdk.java.net/jdk/pull/8549.diff Fetch: git fetch https://git.openjdk.java.net/jdk pull/8549/head:pull/8549 PR: https://git.openjdk.java.net/jdk/pull/8549
