On 01/27/2018 05:42 AM, Konrad Rzeszutek Wilk wrote: > On Fri, Jan 26, 2018 at 07:11:47PM +0000, Hansen, Dave wrote: >> The need for RSB stuffing in all the various scenarios and what the heck it actually mitigates is freakishly complicated. I've tried to write it all down in one place: https://goo.gl/pXbvBE > Thank you for sharing that. > > One question on the third from the top (' RSB Stuff (16) After > irq/nmi/#PF/...'). > > It says that :"Return from interrupt path (more than 16 deep) can empty > RSB". > > Just to clarify - you mean all the returns ('ret') that are happening after > we call do_IRQ and the stack unwinds - but before we do an 'iret' correct? Correct. The RSB is not used or updated by iret.
