Re: [PATCH/RFC 2/2] s390 virtualization interface.

Anthony Liguori
2007-04-27T15:23:08Z

Can you provide a high-level description of how this virtualization
mechanism works? How does MMU virtualization work?

Carsten Otte wrote:
> +
> +#ifndef _ASM_S390_SIE64_H
> +#define _ASM_S390_SIE64_H
> +
> +struct sie_block {
> + atomic_t cpuflags; /* 0x0000 */
> + __u32 prefix; /* 0x0004 */
> + __u32 :32; /* 0x0008 */
> + __u32 :32; /* 0x000c */
> + __u64 :64; /* 0x0010 */
> + __u64 :64; /* 0x0018 */
> + __u64 :64; /* 0x0020 */
> + __u64 cputm; /* 0x0028 */
> + __u64 ckc; /* 0x0030 */
> + __u64 epoch; /* 0x0038 */
> + __u8 svcnn :1, /* 0x0040 */
> + svc1c :1,
> + svc2c :1,
> + svc3c :1,
> + :4;
>

I think bitfields can have weird padding issues.

Regards,

Anthony Liguori