Re: [PATCH] x86/xsave: also save/restore XCR0 across suspend (ACPI S3)

[Keir Fraser <keir.xen@gmail.com>]

On 21/10/2013 09:11, "Jan Beulich" <JBeulich@suse.com> wrote:

> Signed-off-by: Jan Beulich <jbeulich@suse.com>

Acked-by: Keir Fraser <keir@xen.org>

> --- a/xen/arch/x86/acpi/suspend.c
> +++ b/xen/arch/x86/acpi/suspend.c
> @@ -13,12 +13,14 @@
>  #include <asm/hvm/hvm.h>
>  #include <asm/hvm/support.h>
>  #include <asm/i387.h>
> +#include <asm/xstate.h>
>  #include <xen/hypercall.h>
>  
>  static unsigned long saved_lstar, saved_cstar;
>  static unsigned long saved_sysenter_esp, saved_sysenter_eip;
>  static unsigned long saved_fs_base, saved_gs_base, saved_kernel_gs_base;
>  static uint16_t saved_segs[4];
> +static uint64_t saved_xcr0;
>  
>  void save_rest_processor_state(void)
>  {
> @@ -38,6 +40,8 @@ void save_rest_processor_state(void)
>          rdmsrl(MSR_IA32_SYSENTER_ESP, saved_sysenter_esp);
>          rdmsrl(MSR_IA32_SYSENTER_EIP, saved_sysenter_eip);
>      }
> +    if ( cpu_has_xsave )
> +        saved_xcr0 = get_xcr0();
>  }
>  
>  
> @@ -77,6 +81,9 @@ void restore_rest_processor_state(void)
>          do_set_segment_base(SEGBASE_GS_USER_SEL, saved_segs[3]);
>      }
>  
> +    if ( cpu_has_xsave && !set_xcr0(saved_xcr0) )
> +        BUG();
> +
>      /* Maybe load the debug registers. */
>      BUG_ON(is_hvm_vcpu(curr));
>      if ( !is_idle_vcpu(curr) && curr->arch.debugreg[7] )
> 
> 
>