diff options
Diffstat (limited to 'src/arch/x86/transitions/librm.S')
| -rw-r--r-- | src/arch/x86/transitions/librm.S | 23 |
1 files changed, 17 insertions, 6 deletions
diff --git a/src/arch/x86/transitions/librm.S b/src/arch/x86/transitions/librm.S index f2fa8c50..5dacb9b0 100644 --- a/src/arch/x86/transitions/librm.S +++ b/src/arch/x86/transitions/librm.S @@ -210,9 +210,7 @@ VC_TMP_CR3: .space 4 VC_TMP_CR4: .space 4 VC_TMP_EMER: .space 8 .endif -#ifdef TIVOLI_VMM_WORKAROUND VC_TMP_FXSAVE: .space 512 -#endif VC_TMP_END: .previous @@ -350,6 +348,13 @@ init_librm_rmode: /* Initialise IDT */ virtcall init_idt +#ifdef TIVOLI_VMM_WORKAROUND + /* Check for FXSAVE/FXRSTOR */ + clc + virtcall check_fxsr + setnc fxsr_supported +#endif + /* Restore registers */ popl %edi popl %ebx @@ -366,6 +371,10 @@ set_seg_base: roll $16, %eax ret + .section ".data16.fxsr_supported", "awx", @progbits +fxsr_supported: /* FXSAVE/FXRSTOR instructions supported */ + .byte 0 + /**************************************************************************** * real_to_prot (real-mode near call, 32-bit virtual return address) * @@ -1007,10 +1016,11 @@ virt_call: cli movw %cs:rm_ds, %ds -#ifdef TIVOLI_VMM_WORKAROUND /* Preserve FPU, MMX and SSE state in temporary static buffer */ + testb $0xff, fxsr_supported + jz 1f fxsave ( rm_tmpbuf + VC_TMP_FXSAVE ) -#endif +1: /* Preserve GDT and IDT in temporary static buffer */ sidt ( rm_tmpbuf + VC_TMP_IDT ) sgdt ( rm_tmpbuf + VC_TMP_GDT ) @@ -1077,10 +1087,11 @@ vc_rmode: wrmsr .endif -#ifdef TIVOLI_VMM_WORKAROUND /* Restore FPU, MMX and SSE state from temporary static buffer */ + testb $0xff, fxsr_supported + jz 1f fxrstor ( rm_tmpbuf + VC_TMP_FXSAVE ) -#endif +1: /* Restore registers and flags and return */ popl %eax /* skip %cs and %ss */ popw %ds |