LINUX_USRSTACK
if (epp->ep_minsaddr > LINUX_USRSTACK)
epp->ep_minsaddr = LINUX_USRSTACK;
if (epp->ep_minsaddr > LINUX_USRSTACK)
epp->ep_minsaddr = LINUX_USRSTACK;
#ifdef LINUX_USRSTACK
LINUX_USRSTACK < USRSTACK)
*sstack = (unsigned long)LINUX_USRSTACK;