Would be interested to know too, the PDF (page 12, https://comsec.ethz.ch/wp-content/files/retbleed_sec22.pdf https://comsec.ethz.ch/wp-content/files/retbleed_s

Would be interested to know too, the PDF (page 12, https://comsec.ethz.ch/wp-content/files/retbleed_sec22.pdf https://comsec.ethz.ch/wp-content/files/retbleed_sec22.pdf) shows "Intel Core i9-9900K Coffee Lake Ref" but does not list the stepping. Per https://www.intel.com/content/www/us/en/developer/topic-technology/software-security-guidance/processors-affected-consolidated-product-cpu-model.html https://www.intel.com/content/www/us/en/developer/topic-tech... (click 2022 tab), there's C and D steppings of 9900k. Note Intel recommends some software mitgations for both steppings. (It looks like the kernel decided it was too confusing to handle different steppings and is applying the mitigation to all: https://lore.kernel.org/lkml/20220712183239.024698478@linuxfoundation.org/ https://lore.kernel.org/lkml/20220712183239.024698478@linuxf... so maybe doesn't matter either way.)