diff options
| -rw-r--r-- | src/arch/x86/isa/insts/romutil.py | 27 |
1 files changed, 14 insertions, 13 deletions
diff --git a/src/arch/x86/isa/insts/romutil.py b/src/arch/x86/isa/insts/romutil.py index 1345c3d05..a39ba202f 100644 --- a/src/arch/x86/isa/insts/romutil.py +++ b/src/arch/x86/isa/insts/romutil.py @@ -80,29 +80,22 @@ def rom andi t10, t10, 3, dataSize=8 rdattr t5, cs, dataSize=8 srli t5, t5, 3, dataSize=8 - sub t5, t5, t10, dataSize=8 - andi t0, t5, 0x3, flags=(EZF,), dataSize=8 + andi t5, t5, 0x3, dataSize=8 + sub t0, t5, t10, flags=(EZF,), dataSize=8 # We're going to change priviledge, so zero out the stack selector. We # need to let the IST have priority so we don't branch yet. wrsel t11, t0, flags=(nCEZF,) # Check the IST field of the gate descriptor - srli t10, t4, 32, dataSize=8 - andi t10, t10, 0x7, dataSize=8 - subi t0, t10, 1, flags=(ECF,), dataSize=8 + srli t12, t4, 32, dataSize=8 + andi t12, t12, 0x7, dataSize=8 + subi t0, t12, 1, flags=(ECF,), dataSize=8 br rom_local_label("%(startLabel)s_istStackSwitch"), flags=(nCECF,) br rom_local_label("%(startLabel)s_cplStackSwitch"), flags=(nCEZF,) # If we're here, it's because the stack isn't being switched. # Set t6 to the new aligned rsp. mov t6, t6, rsp, dataSize=8 - andi t6, t6, 0xF0, dataSize=1 - subi t6, t6, 40 + %(errorCodeSize)d, dataSize=8 - - # Check that we can access everything we need to on the stack - ldst t0, hs, [1, t0, t6], dataSize=8, addressSize=8 - ldst t0, hs, [1, t0, t6], \ - 32 + %(errorCodeSize)d, dataSize=8, addressSize=8 br rom_local_label("%(startLabel)s_stackSwitched") %(startLabel)s_istStackSwitch: @@ -110,10 +103,18 @@ def rom br rom_local_label("%(startLabel)s_stackSwitched") %(startLabel)s_cplStackSwitch: - panic "CPL change initiated stack switching isn't implemented" + # Get the new rsp from the TSS + ld t6, tr, [8, t10, t0], 4, dataSize=8, addressSize=8 %(startLabel)s_stackSwitched: + andi t6, t6, 0xF0, dataSize=1 + subi t6, t6, 40 + %(errorCodeSize)d, dataSize=8 + + # Check that we can access everything we need to on the stack + ldst t0, hs, [1, t0, t6], dataSize=8, addressSize=8 + ldst t0, hs, [1, t0, t6], \ + 32 + %(errorCodeSize)d, dataSize=8, addressSize=8 ## ## Point of no return. |