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Fixed ctrl_xfer_pro.cc for 64-bit iret. Check for null selector

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was not correct (used == 0, rather than s&0xffc == 0).  Also,
  with a null SS selector, it was fetching the descriptor anyways.
  Put more code inside the if (selector != NULL) clause.
  For a temporary measure I added the local INIT_64_DESCRIPTOR
  from segment_ctrl_pro.cc, and used it in the case that the
  SS selector is null.  We need to make a real function which
  sets a descriptor in long-mode to nominal values.  I'm going
  to do that next... I can't stand seeing the current hacks.  :^)
This commit is contained in:
Kevin Lawton 2002-09-24 15:41:03 +00:00
parent 05084fd759
commit 6e7e4c2431
1 changed files with 27 additions and 35 deletions
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62
bochs/cpu/ctrl_xfer_pro.cc
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@ -1,5 +1,5 @@
/////////////////////////////////////////////////////////////////////////
// $Id: ctrl_xfer_pro.cc,v 1.18 2002-09-24 08:29:05 bdenney Exp $
// $Id: ctrl_xfer_pro.cc,v 1.19 2002-09-24 15:41:03 kevinlawton Exp $
/////////////////////////////////////////////////////////////////////////
//
// Copyright (C) 2001 MandrakeSoft S.A.
@ -38,6 +38,14 @@
#endif
#define INIT_64_DESCRIPTOR(descriptor) \
{ \
(descriptor).u.segment.base = 0; \
(descriptor).u.segment.limit_scaled = 0xffffffff; \
(descriptor).valid = 1; \
}
#if BX_CPU_LEVEL >= 2
void
BX_CPU_C::jump_protected(bxInstruction_c *i, Bit16u cs_raw, bx_address dispBig)
@ -1607,37 +1615,24 @@ BX_CPU_C::iret_protected(bxInstruction_c *i)
// return;
// }
if ( (raw_ss_selector & 0xfffc) != 0 ) {
parse_selector(raw_ss_selector, &ss_selector);
#if KPL64Hacks
unsigned ssIsNull = 0;
if ( (raw_ss_selector & 0xfffc) == 0 ) {
BX_INFO(("iret: SS NULL OK in LM"));
parse_selector(0,&ss_selector);
parse_descriptor(0,0,&ss_descriptor);
load_ss_null(&ss_selector, &ss_descriptor, cs_descriptor.dpl);
ssIsNull = 1;
goto afterSSChecks;
}
#endif
/* selector RPL must = RPL of return CS selector,
* else #GP(SS selector) */
if ( ss_selector.rpl != cs_selector.rpl) {
BX_PANIC(("iret: SS.rpl != CS.rpl"));
exception(BX_GP_EXCEPTION, raw_ss_selector & 0xfffc, 0);
return;
}
parse_selector(raw_ss_selector, &ss_selector);
/* selector index must be within its descriptor table limits,
* else #GP(SS selector) */
fetch_raw_descriptor(&ss_selector, &dword1, &dword2,
BX_GP_EXCEPTION);
/* selector RPL must = RPL of return CS selector,
* else #GP(SS selector) */
if ( ss_selector.rpl != cs_selector.rpl) {
BX_PANIC(("iret: SS.rpl != CS.rpl"));
exception(BX_GP_EXCEPTION, raw_ss_selector & 0xfffc, 0);
return;
}
parse_descriptor(dword1, dword2, &ss_descriptor);
/* selector index must be within its descriptor table limits,
* else #GP(SS selector) */
fetch_raw_descriptor(&ss_selector, &dword1, &dword2,
BX_GP_EXCEPTION);
parse_descriptor(dword1, dword2, &ss_descriptor);
if (raw_ss_selector != 0) {
/* AR byte must indicate a writable data segment,
* else #GP(SS selector) */
if ( ss_descriptor.valid==0 ||
@ -1665,10 +1660,6 @@ if ( (raw_ss_selector & 0xfffc) == 0 ) {
}
}
#if KPL64Hacks
afterSSChecks:
#endif
access_linear(BX_CPU_THIS_PTR sregs[BX_SEG_REG_SS].cache.u.segment.base + temp_RSP + 0,
8, 0, BX_READ, &new_rip);
access_linear(BX_CPU_THIS_PTR sregs[BX_SEG_REG_SS].cache.u.segment.base + temp_RSP + 16,
@ -1698,13 +1689,14 @@ afterSSChecks:
else
write_flags((Bit16u) new_eflags, prev_cpl==0, prev_cpl<=BX_CPU_THIS_PTR get_IOPL());
#if KPL64Hacks
if (!ssIsNull) {
if ( (raw_ss_selector & 0xfffc) != 0 ) {
// load SS:RSP from stack
// load the SS-cache with SS descriptor
load_ss(&ss_selector, &ss_descriptor, cs_selector.rpl);
}
#endif
else {
INIT_64_DESCRIPTOR(BX_CPU_THIS_PTR sregs[BX_SEG_REG_SS].cache);
}
RSP = new_rsp;
validate_seg_regs();