On Tue Apr 28, 2015 at 11:27:31 +0800, watermirror wrote:

hi, after entered the entry_sys_fast_ipc_c through sysenter, why the first instruction is 'pop %esp'?

With sysenter, kernel is always entered on the same stack memory (see MSR_SYSENTER_ESP), so the current stack is stored there and loaded via the pop. Adam -- Adam adam@os.inf.tu-dresden.de Lackorzynski http://os.inf.tu-dresden.de/~adam/