mchehab: Is this softirq issue a patch that's *in* 4.9, or since it - i.e. in v.4.10 ?
aha - found the commit
v4.8-rc7-52-g4cd13c21b207 :D
yes commit 4cd13c21b207e80ddb1144c576500098f2d5f882
it will probably be replaced by something like: https://patchwork.kernel.org/patch/10150455/
or something even less aggressive
mchehab: Thanks for the pointers :D