Re: [PATCH] add sysenter/syscall emulation for 32bit compat mode

Amit Shah
2009-06-17T05:02:38Z

Hi Andre,

On (Tue) Jun 16 2009 [15:25:13], Andre Przywara wrote:
> sysenter/sysexit are not supported on AMD's 32bit compat mode, whereas
> syscall is not supported on Intel's 32bit compat mode. To allow cross
> vendor migration we emulate the missing instructions by setting up the
> processor state accordingly.
> The sysenter code was originally sketched by Amit Shah, it was completed,
> debugged, syscall added and made-to-work by Christoph Egger and polished
> up by Andre Przywara.
> Please note that sysret does not need to be emulated, because it will be
> exectued in 64bit mode and returning to 32bit compat mode works on Intel.

Thanks for picking this up. You also had a testcase for this, right?

Amit