Hi, there are a couple of commits queued for 4.19 that fix some memory leaks: https://patchwork.kernel.org/patch/10594683/ and https://patchwork.kernel.org/patch/10594681/. Looking at the call trace I'd say the first patch is going to fix your issue.
They should both be included in the stable trees given the tag in the commit. Regards, Gabriele
