On 18/01/19 22:20, Sean Christopherson wrote: > ...and of course actually call it from C now that the assembly code is > in a dedicated sub-routine and has been cleansed of any quirks that > would break compliance with the kernel's x86 calling conventions. I'm not sure about removing the clobbering. If the stack is outside L1, could this lead to speculative execution with the guest values in the registers? No problem with patches 1-26 though. Paolo