1.1 --- a/xen/arch/x86/domain.c	Thu Apr 21 09:14:12 2005 +0000
     1.2 +++ b/xen/arch/x86/domain.c	Thu Apr 21 10:15:23 2005 +0000
     1.3 @@ -632,17 +632,17 @@ static void load_segments(struct exec_do
     1.4          else
     1.5              regs->cs &= ~3;
     1.6  
     1.7 -        if ( put_user(regs->ss,     rsp- 1) |
     1.8 -             put_user(regs->rsp,    rsp- 2) |
     1.9 -             put_user(regs->rflags, rsp- 3) |
    1.10 -             put_user(regs->cs,     rsp- 4) |
    1.11 -             put_user(regs->rip,    rsp- 5) |
    1.12 -             put_user(regs->gs,     rsp- 6) |
    1.13 -             put_user(regs->fs,     rsp- 7) |
    1.14 -             put_user(regs->es,     rsp- 8) |
    1.15 -             put_user(regs->ds,     rsp- 9) |
    1.16 -             put_user(regs->r11,    rsp-10) |
    1.17 -             put_user(regs->rcx,    rsp-11) )
    1.18 +        if ( put_user(regs->ss,             rsp- 1) |
    1.19 +             put_user(regs->rsp,            rsp- 2) |
    1.20 +             put_user(regs->rflags,         rsp- 3) |
    1.21 +             put_user(regs->cs,             rsp- 4) |
    1.22 +             put_user(regs->rip,            rsp- 5) |
    1.23 +             put_user(n->arch.user_ctxt.gs, rsp- 6) |
    1.24 +             put_user(n->arch.user_ctxt.fs, rsp- 7) |
    1.25 +             put_user(n->arch.user_ctxt.es, rsp- 8) |
    1.26 +             put_user(n->arch.user_ctxt.ds, rsp- 9) |
    1.27 +             put_user(regs->r11,            rsp-10) |
    1.28 +             put_user(regs->rcx,            rsp-11) )
    1.29          {
    1.30              DPRINTK("Error while creating failsafe callback frame.\n");
    1.31              domain_crash();
    1.32 @@ -737,7 +737,7 @@ static void __context_switch(void)
    1.33      {
    1.34          memcpy(&p->arch.user_ctxt,
    1.35                 stack_ec, 
    1.36 -               sizeof(*stack_ec));
    1.37 +               CTXT_SWITCH_STACK_BYTES);
    1.38          unlazy_fpu(p);
    1.39          CLEAR_FAST_TRAP(&p->arch);
    1.40          save_segments(p);
    1.41 @@ -747,7 +747,7 @@ static void __context_switch(void)
    1.42      {
    1.43          memcpy(stack_ec,
    1.44                 &n->arch.user_ctxt,
    1.45 -               sizeof(*stack_ec));
    1.46 +               CTXT_SWITCH_STACK_BYTES);
    1.47  
    1.48          /* Maybe switch the debug registers. */
    1.49          if ( unlikely(n->arch.debugreg[7]) )

     2.1 --- a/xen/include/asm-x86/x86_32/regs.h	Thu Apr 21 09:14:12 2005 +0000
     2.2 +++ b/xen/include/asm-x86/x86_32/regs.h	Thu Apr 21 10:15:23 2005 +0000
     2.3 @@ -15,4 +15,7 @@
     2.4  #define PERMIT_SOFTINT(_dpl, _e, _r) \
     2.5      ((_dpl) >= (VM86_MODE(_r) ? 3 : ((_r)->cs & 3)))
     2.6  
     2.7 +/* Number of bytes of on-stack execution state to be context-switched. */
     2.8 +#define CTXT_SWITCH_STACK_BYTES (sizeof(execution_context_t))
     2.9 +
    2.10  #endif

     3.1 --- a/xen/include/asm-x86/x86_64/regs.h	Thu Apr 21 09:14:12 2005 +0000
     3.2 +++ b/xen/include/asm-x86/x86_64/regs.h	Thu Apr 21 10:15:23 2005 +0000
     3.3 @@ -15,4 +15,8 @@
     3.4  #define PERMIT_SOFTINT(_dpl, _e, _r) \
     3.5      ((_dpl) >= (KERNEL_MODE(_e, _r) ? 1 : 3))
     3.6  
     3.7 +/* Number of bytes of on-stack execution state to be context-switched. */
     3.8 +/* NB. Segment registers and bases are not saved/restored on x86/64 stack. */
     3.9 +#define CTXT_SWITCH_STACK_BYTES (offsetof(execution_context_t, es))
    3.10 +
    3.11  #endif