Re: [PATCH] x86/HVM: support emulated UMIP

2021-02-05 Thread Jan Beulich
On 04.02.2021 15:10, Andrew Cooper wrote: > On 29/01/2021 11:45, Jan Beulich wrote: >> +{ >> +u32 general1_intercepts = vmcb_get_general1_intercepts(vmcb); >> + >> +if ( v->arch.hvm.guest_cr[4] & X86_CR4_UMIP ) >> +{ >> +value &= ~X86_CR4_

Re: [PATCH] x86/HVM: support emulated UMIP

2021-02-05 Thread Jan Beulich
On 04.02.2021 15:10, Andrew Cooper wrote: > On 29/01/2021 11:45, Jan Beulich wrote: >> There are three noteworthy drawbacks: >> 1) The intercepts we need to enable here are CPL-independent, i.e. we >>now have to emulate certain instructions for ring 0. >> 2) On VMX there's no intercept for SMSW

Re: [PATCH] x86/HVM: support emulated UMIP

2021-02-04 Thread Andrew Cooper
On 29/01/2021 11:45, Jan Beulich wrote: > There are three noteworthy drawbacks: > 1) The intercepts we need to enable here are CPL-independent, i.e. we >now have to emulate certain instructions for ring 0. > 2) On VMX there's no intercept for SMSW, so the emulation isn't really >complete th

RE: [PATCH] x86/HVM: support emulated UMIP

2021-02-02 Thread Tian, Kevin
> From: Jan Beulich > Sent: Friday, January 29, 2021 7:45 PM > > There are three noteworthy drawbacks: > 1) The intercepts we need to enable here are CPL-independent, i.e. we >now have to emulate certain instructions for ring 0. > 2) On VMX there's no intercept for SMSW, so the emulation isn'

Re: [PATCH] x86/HVM: support emulated UMIP

2021-01-29 Thread Jan Beulich
On 29.01.2021 12:45, Jan Beulich wrote: > There are three noteworthy drawbacks: > 1) The intercepts we need to enable here are CPL-independent, i.e. we >now have to emulate certain instructions for ring 0. > 2) On VMX there's no intercept for SMSW, so the emulation isn't really >complete th