On 8/6/2026 9:15 AM, Sohil Mehta wrote: > From: Zeng Guang <[email protected]> > > When Linear Address Space Separation (LASS) is enabled, the processor > applies a LASS violation check on every access to a linear address. To > align with hardware behavior, KVM needs to perform the same check during > instruction emulation before consulting the page tables. > > Add a new callback to x86_emulate_ops to let the emulator query whether > an access would trigger a LASS violation. The callback takes the linear > address and the size that describe the memory access, plus a set of > flags that convey the type of access. > > Add the LASS violation check to __linearize() so that every explicit > guest memory access is validated along with the other linear address > checks. The SDM (June 2026), Vol3, Chapter 4, specifically states that > there is no relative ordering between the canonicality check and the > LASS violation check. Also, there is no prioritization specified between > the faults generated by alignment checks and LASS violations. > > Implicit supervisor accesses bypass __linearize(). So, add LASS checks > for those in linear_read_system() and linear_write_system() and tag the > access as implicit. > > For now, emulator_is_lass_violation() is a no-op. Later, it will be > wired up to the VMX implementation. > > Signed-off-by: Zeng Guang <[email protected]> > Signed-off-by: Binbin Wu <[email protected]>
My SoB can be dropped. > Signed-off-by: Sohil Mehta <[email protected]> Reviewed-by: Binbin Wu <[email protected]>
