https://bugzilla.kernel.org/show_bug.cgi?id=214029
--- Comment #25 from Erhard F. (erhard_f@mailbox.org) --- (In reply to Jan Steffens from comment #24)
Looks like this was mistakenly picked into LTS 5.10, which does not contain d02117f8efaa5fbc37437df1ae955a147a2a424a.
As Christian wrote in comment 21 the patches bisected didn't cause the memleak, but rather just made it more likely to appear. So the patch (0db55f9a1bafbe3dac750ea669de9134922389b5) most probably wandered correctly in 5.10 LTS and 5.4 LTS.