On Fri, Sep 17, 2021 at 8:10 AM Brendan Higgins brendanhiggins@google.com wrote:
The structleak plugin causes the stack frame size to grow immensely when used with KUnit; this is caused because KUnit allocates lots of moderately sized structs on the stack as part of its assertion macro implementation. For most tests with small to moderately sized tests cases there are never enough KUnit assertions to be an issue at all; even when a single test cases has many KUnit assertions, the compiler should never put all these struct allocations on the stack at the same time since the scope of the structs is so limited; however, the structleak plugin does not seem to respect the compiler doing the right thing and will still warn of excessive stack size in some cases.
These patches are not a permanent solution since new tests can be added with huge test cases, but this serves as a stop gap to stop structleak from being used on KUnit tests which will currently result in excessive stack size.
Of the following patches, I think the thunderbolt patch may be unnecessary since Linus already fixed that test. Additionally, I was not able to reproduce the error on the sdhci-of-aspeed test. Nevertheless, I included these tests cases for completeness. Please see my discussion with Arnd for more context[1].
NOTE: Arnd did the legwork for most of these patches, but did not actually share code for some of them, so I left his Signed-off-by off of those patches as I don't want to misrepresent him. Arnd, please sign off on those patches at your soonest convenience.
Thanks a lot for picking up this work where I dropped the ball.
Patches 1-5 look good to me, and I replied on one remaining issue I see with patch 6. I think you did more work on these that I did, by doing a nice write-up and splitting them into separate patches with useful changelogs, you should keep authorship, and just change my S-o-b to Suggested-by.
If you prefer to keep me as the author, then the correct way would be to commit them with --author= to ensure that the author and first s-o-b match.
Arnd