On Fri, 30 Oct 2026 03:19:37 GMT, Long Yang <[email protected]> wrote:
>> Hi, could I have a review of this patch. This patch fixes >> [JDK-8391637](https://bugs.openjdk.org/browse/JDK-8391637). >> >> Due to my GitHub account settings (Enable Copilot Code Review for all my >> PRs), my previous [PR](https://github.com/openjdk/jdk/pull/33358) had >> Copilot Review enabled by default. I have disabled it and now open this new >> PR, with no changes made to the code. >> >> On `risc-v`, >> [LinuxRISCV64CFrame.sender()](https://github.com/openjdk/jdk/blob/c368bac40e185398fbc40dc4d75a457f7a36f954/src/jdk.hotspot.agent/share/classes/sun/jvm/hotspot/debugger/linux/riscv64/LinuxRISCV64CFrame.java#L70) >> validates only FP alignment, then dereferences FP for SP, link, and return >> address. An aligned arbitrary FP (such as 0x90) can therefore cause >> UnmappedAddressException, and lead to incomplete stack for the target thread. >> >> `aarch64` and `amdf64`already use `dwarf` to unwind native frames, see >> https://github.com/openjdk/jdk/blob/c368bac40e185398fbc40dc4d75a457f7a36f954/src/jdk.hotspot.agent/share/classes/sun/jvm/hotspot/debugger/linux/amd64/LinuxAMD64CFrame.java#L36 >> https://github.com/openjdk/jdk/blob/c368bac40e185398fbc40dc4d75a457f7a36f954/src/jdk.hotspot.agent/share/classes/sun/jvm/hotspot/debugger/linux/aarch64/LinuxAARCH64CFrame.java#L38 >> >> This patch makes `risc-v` to unwind with `dwarf` too. >> >> The `risc-v` version basically has the same design as the `aarch64` version. >> There are also several differences , primarily due to differences in calling >> conventions. Almost every difference is accompanied by an explanatory >> comment. >> >> I have ran tests in `test/hotspot/jtreg/serviceability/sa` on `risc-v` and >> `amd64`, all passed. >> >> --------- >> - [x] I confirm that I make this contribution in accordance with the >> [OpenJDK Interim AI Policy](https://openjdk.org/legal/ai). > > Long Yang has updated the pull request with a new target base due to a merge > or a rebase. The pull request now contains eight commits: > > - Enable TestJhsdbJstackMixedWithXComp.java on riscv64 while excluding QEMU > environments > - Enable -fasynchronous-unwind-tables for linux-riscv64 > - Add try/catch for memory-read exceptions in getSenderFP > - RISC-V: Use compiler-defined macros for DWARF register selection > - Recover caller return addresses across save helpers > - Use the CIE return-address column instead of the hard-coded RA register > - Add comment > - 8391637: On the RISC-V platform, TestJhsdbJstackMixed has a certain > probability of failure Thanks everyone for the reviews. About the force-push: I rebased this PR on top of [JDK-8395826](https://bugs.openjdk.org/browse/JDK-8395826), following your suggestion. I didn't know the bot warns against this. If it's not recommended, from now on I'll merge `master` into the branch instead of rebasing. The force-push changed one thing only: `dwarf.cpp` is no longer in the diff. The master now carries the same `_current_pc <= pc` line. Everything else in the diff is identical to what was on the PR before the force-push. https://github.com/openjdk/jdk/blob/6cf31a5e10084bd171a63908deb8bfce7443e448/src/jdk.hotspot.agent/linux/native/libsaproc/dwarf.cpp#L176 Testing: I ran the full `test/hotspot/jtreg/serviceability/sa` suite on a RISC-V 64 machine — all tests passed. Since the PR already has approvals from @DingliZhang, @plummercj and @YaSuenag, may I `/integrate`? ------------- PR Comment: https://git.openjdk.org/jdk/pull/33374#issuecomment-6517566495
