[Xen-devel] [PATCH] x86_emulate: Always truncate %eip in 32bit mode

_regs.eip needs to be truncated after having size added to it, or emulating an instruction which crosses the 4GB boundary causes _regs.eip to become invalid, and fail vmentry checks when returning back to the guest. The comment /* real hardware doesn't truncate */ seems to appear in c/s ddef8e16

Re: [Xen-devel] [PATCH] x86_emulate: Always truncate %eip in 32bit mode

>>> On 30.11.15 at 12:07, wrote: > _regs.eip needs to be truncated after having size added to it, or emulating an > instruction which crosses the 4GB boundary causes _regs.eip to become invalid, > and fail vmentry checks when returning back to the guest. > > The