Re: [kvm-devel] [GFXBOOT] [PATCH] When switching to real-mode, pass SS in a GP register

2007-10-11 Thread Anthony Liguori
Steffen Winterfeldt wrote: Hi, sorry for the delay, but I've been on vacation. :-) No worries :-) You're right. Good catch! Actually that is not true. 'mov eax,ss' does implicitly clear the upper 16 bits (both processor docs and hardware agree here). I wasn't able to find

Re: [kvm-devel] [GFXBOOT] [PATCH] When switching to real-mode, pass SS in a GP register

2007-10-08 Thread Steffen Winterfeldt
Hi, sorry for the delay, but I've been on vacation. :-) On Sun, 30 Sep 2007, Anthony Liguori wrote: Avi Kivity wrote: Anthony Liguori wrote: As Avi pointed out, VT requires that SS.RPL == CS.RPL. We're seeing gfxboot fail under KVM because ss = 0x5761 while cs = 0x4004 during the

Re: [kvm-devel] [GFXBOOT] [PATCH] When switching to real-mode, pass SS in a GP register

2007-09-30 Thread Avi Kivity
Anthony Liguori wrote: Hi Steffen, As Avi pointed out, VT requires that SS.RPL == CS.RPL. We're seeing gfxboot fail under KVM because ss = 0x5761 while cs = 0x4004 during the transition from real mode to protected mode. The attached patch passes the value of ss through ebx since KVM has to

Re: [kvm-devel] [GFXBOOT] [PATCH] When switching to real-mode, pass SS in a GP register

2007-09-30 Thread Anthony Liguori
Avi Kivity wrote: Anthony Liguori wrote: Hi Steffen, As Avi pointed out, VT requires that SS.RPL == CS.RPL. We're seeing gfxboot fail under KVM because ss = 0x5761 while cs = 0x4004 during the transition from real mode to protected mode. The attached patch passes the value of ss through

[kvm-devel] [GFXBOOT] [PATCH] When switching to real-mode, pass SS in a GP register

2007-09-29 Thread Anthony Liguori
Hi Steffen, As Avi pointed out, VT requires that SS.RPL == CS.RPL. We're seeing gfxboot fail under KVM because ss = 0x5761 while cs = 0x4004 during the transition from real mode to protected mode. The attached patch passes the value of ss through ebx since KVM has to sanitize the value of