PSL_SPV
l->l_md.md_utf->tf_srr1 |= PSL_SPV;
mtmsr((msr & ~PSL_EE) | PSL_SPV);
l->l_md.md_utf->tf_srr1 &= ~PSL_SPV;
mcp->__gregs[_REG_MSR] |= PSL_SPV;
mtmsr((msr & ~PSL_EE) | PSL_SPV);
#define PSL_USERMASK (PSL_SPV | PSL_CE | 0xFFFF)