Re: [patch uq/master 7/8] MCE: Relay UCR MCE to guest

Hidetoshi Seto
2010-10-06T01:59:04Z

I got some more question:

(2010/10/05 3:54), Marcelo Tosatti wrote:
> Index: qemu/target-i386/cpu.h
> ===================================================================
> --- qemu.orig/target-i386/cpu.h
> +++ qemu/target-i386/cpu.h
> @@ -250,16 +250,32 @@
> #define PG_ERROR_RSVD_MASK 0x08
> #define PG_ERROR_I_D_MASK 0x10
>
> -#define MCG_CTL_P (1UL<<8) /* MCG_CAP register available */
> +#define MCG_CTL_P (1ULL<<8) /* MCG_CAP register available */
> +#define MCG_SER_P (1ULL<<24) /* MCA recovery/new status bits */
>
> -#define MCE_CAP_DEF MCG_CTL_P
> +#define MCE_CAP_DEF (MCG_CTL_P|MCG_SER_P)
> #define MCE_BANKS_DEF 10
>

It seems that current kvm doesn't support SER_P, so injecting SRAO
to guest will mean that guest receives VAL|UC|!PCC and RIPV event
from virtual processor that doesn't have SER_P.

I think most OSes don't expect that it can receives MCE with !PCC
on traditional x86 processor without SER_P.

Q1: Is it safe to expect that guests can handle such !PCC event?
Q2: What is the expected behavior on the guest?
Q3: What happen if guest reboots itself in response to the MCE?

Thanks,
H.Seto