the first instruction in entry_sys_fast_ipc_c

Adam Lackorzynski adam at
Tue Apr 28 22:43:48 CEST 2015

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 at

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