linux-user/i386: Emulate x86_64 vsyscalls

Notice the magic page during translate, much like we already
do for the arm32 commpage.  At runtime, raise an exception to
return cpu_loop for emulation.

Reviewed-by: Paolo Bonzini <pbonzini@redhat.com>
Signed-off-by: Richard Henderson <richard.henderson@linaro.org>
Message-Id: <20200213032223.14643-4-richard.henderson@linaro.org>
Signed-off-by: Laurent Vivier <laurent@vivier.eu>
3 files changed