Re: [PATCH try #2] kvm-12 userland guest reboot fix

[Avi Kivity <avi-atKUWr5tajBWk0Htik3J/w@public.gmane.org>]

Joerg Roedel wrote:
> From: Markus Rechberger <markus.rechberger-5C7GfCeVMHo@public.gmane.org>
> From: Joerg Roedel <joerg.roedel-5C7GfCeVMHo@public.gmane.org>
>
> This patch fixes the initialization of the segment registers which
> solves the triple fault and keyboard controller reset problems in
> kvm/qemu guests as well as the slow grub menu interaction. The patch
> should also work on Intel VMX now.
>   
> diff -upr kvm-12/qemu/target-i386/helper2.c kvm-12-reboot-fixed/qemu/target-i386/helper2.c
> --- kvm-12/qemu/target-i386/helper2.c	2006-12-31 14:31:38.000000000 +0100
> +++ kvm-12-reboot-fixed/qemu/target-i386/helper2.c	2007-01-23 20:24:42.265987000 +0100
> @@ -151,6 +151,9 @@ CPUX86State *cpu_x86_init(void)
>  void cpu_reset(CPUX86State *env)
>  {
>      int i;
> +    unsigned int flags = DESC_P_MASK |
> +                         DESC_S_MASK |
> +                         (2 << DESC_TYPE_SHIFT);
>  
>      memset(env, 0, offsetof(CPUX86State, breakpoints));
>  
> @@ -173,9 +176,9 @@ void cpu_reset(CPUX86State *env)
>      env->tr.flags = DESC_P_MASK;
>      
>      cpu_x86_load_seg_cache(env, R_CS, 0xf000, 0xffff0000, 0xffff, 0); 
> -    cpu_x86_load_seg_cache(env, R_DS, 0, 0, 0xffff, 0);
> -    cpu_x86_load_seg_cache(env, R_ES, 0, 0, 0xffff, 0);
> -    cpu_x86_load_seg_cache(env, R_SS, 0, 0, 0xffff, 0);
> +    cpu_x86_load_seg_cache(env, R_DS, 0, 0, 0xffff, flags);
> +    cpu_x86_load_seg_cache(env, R_ES, 0, 0, 0xffff, flags);
> +    cpu_x86_load_seg_cache(env, R_SS, 0, 0, 0xffff, flags);
>      cpu_x86_load_seg_cache(env, R_FS, 0, 0, 0xffff, 0);
>      cpu_x86_load_seg_cache(env, R_GS, 0, 0, 0xffff, 0);
>   

This changes core qemu code, which may make merging our code back to 
qemu more difficult.  It also means we need to test with -no-kvm.

Can you try making load_regs() in qemu-kvm.c detect the case of flags == 
0 (perhaps only if cr0.pg == 0) and changing it only then?  It should 
have the same effect.



-- 
error compiling committee.c: too many arguments to function


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