Re: [PATCH 0/3] KVM: Introduce VCPU-wide notion of guest-mode V2
On Mon, Nov 29, 2010, Joerg Roedel wrote about [PATCH 0/3] KVM: Introduce VCPU-wide notion of guest-mode V2: Hi Avi, Hi Marcelo, here is the re-spin I promised. The change to V1 are essentially the renames: kvm_vcpu_enter_gm - enter_guest_mode kvm_vcpu_leave_gm - leave_guest_mode kvm_vcpu_is_gm- is_guest_mode I like this concept, and will be happy to change the nested VMX code to use it as well. One small thing: After the name change, it might not be obvious on first sight that these functions refer to the state of the vcpu, not the state of the actual CPU (which, if you think about it, is never in guest mode while KVM code is running ;-)). I think that a short comment before the definition of these functions might be useful - perhaps saying that they pertain to a hypervisor running in the vcpu (i.e., nested virtualization). Nadav. -- Nadav Har'El| Wednesday, Dec 1 2010, 24 Kislev 5771 n...@math.technion.ac.il |- Phone +972-523-790466, ICQ 13349191 |How do you get holy water? Boil the hell http://nadav.harel.org.il |out of it. -- To unsubscribe from this list: send the line unsubscribe kvm in the body of a message to majord...@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html
Re: [PATCH 0/3] KVM: Introduce VCPU-wide notion of guest-mode V2
On Wed, Dec 01, 2010 at 03:01:49AM -0500, Nadav Har'El wrote: On Mon, Nov 29, 2010, Joerg Roedel wrote about [PATCH 0/3] KVM: Introduce VCPU-wide notion of guest-mode V2: Hi Avi, Hi Marcelo, here is the re-spin I promised. The change to V1 are essentially the renames: kvm_vcpu_enter_gm - enter_guest_mode kvm_vcpu_leave_gm - leave_guest_mode kvm_vcpu_is_gm- is_guest_mode I like this concept, and will be happy to change the nested VMX code to use it as well. One small thing: After the name change, it might not be obvious on first sight that these functions refer to the state of the vcpu, not the state of the actual CPU (which, if you think about it, is never in guest mode while KVM code is running ;-)). I think that a short comment before the definition of these functions might be useful - perhaps saying that they pertain to a hypervisor running in the vcpu (i.e., nested virtualization). Yes, right. Thats a good thing. I sent a follow-on patch adding the comments. Btw, another idea which came up recently was to concentrate the actuall vmexit emulation at a single point. Every code place which does the exit directly today will be changed to only set a request-bit and the real exit is then done later. Your code might already do this, I havn't checked. In fact the idea is from the neste-VMX patchset for Xen :) This would fit very well in the generic code because it already has request-bit infrastructure. What do you think, can nested VMX also make use of that too? Joerg -- AMD Operating System Research Center Advanced Micro Devices GmbH Einsteinring 24 85609 Dornach General Managers: Alberto Bozzo, Andrew Bowd Registration: Dornach, Landkr. Muenchen; Registerger. Muenchen, HRB Nr. 43632 -- To unsubscribe from this list: send the line unsubscribe kvm in the body of a message to majord...@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html
Re: [PATCH 0/3] KVM: Introduce VCPU-wide notion of guest-mode V2
On Wed, Dec 01, 2010, Roedel, Joerg wrote about Re: [PATCH 0/3] KVM: Introduce VCPU-wide notion of guest-mode V2: Btw, another idea which came up recently was to concentrate the actuall vmexit emulation at a single point. Every code place which does the exit directly today will be changed to only set a request-bit and the real exit is then done later. Your code might already do this, I havn't In my current patches, there is single function nested_vmx_vmexit() which emulates the exit (exits from L2 to L1), but it is called in several places, the most significant are of course in vmx_handle_exit (when L1 asked an exit on the given event), and vmx_interrupt_allowed (when we inject an interrupt and L1 asked to exit on interrupts). This area of my code definitely needs some reorganization, as Gleb pointed out in his review. This would fit very well in the generic code because it already has request-bit infrastructure. What do you think, can nested VMX also make use of that too? Can you please say a few words why you'd want to move this nested-exit request bit to x86.c? Do you want to move some of the exit logic to x86.c - e.g., for the injection logic? Nadav. -- Nadav Har'El| Wednesday, Dec 1 2010, 24 Kislev 5771 n...@math.technion.ac.il |- Phone +972-523-790466, ICQ 13349191 |Fame: when your name is in everything but http://nadav.harel.org.il |the phone book. -- To unsubscribe from this list: send the line unsubscribe kvm in the body of a message to majord...@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html
Re: [PATCH 0/3] KVM: Introduce VCPU-wide notion of guest-mode V2
On Wed, Dec 01, 2010 at 06:38:30AM -0500, Nadav Har'El wrote: Can you please say a few words why you'd want to move this nested-exit request bit to x86.c? I don't want to move the actual exit-code itself into generic code. This code is different between svm and vmx. I think we could implement a call-back in kvm_x86_ops which is called when a vmexit is requested. The benefit is that we have a single and well-defined place where we emulate a vmexit. SVM already as a similar mechanism internally because nested_svm_vmexit may sleep and can't be called from certain places. Another reason is that emulating a vmexit at a wrong plase may have side-effects (for example when called from within the instruction emulator). With a generic request-bit I can remove the SVM internal implementation and nested vmx could use it too. I am certain you will need something similar in nested-vmx too. Do you want to move some of the exit logic to x86.c - e.g., for the injection logic? Thats another and probably more complex topic. I need a better understanding of (nested-)vmx before we discuss how this can be done. But a vmexit-callback may be helpful there as well. Joerg -- AMD Operating System Research Center Advanced Micro Devices GmbH Einsteinring 24 85609 Dornach General Managers: Alberto Bozzo, Andrew Bowd Registration: Dornach, Landkr. Muenchen; Registerger. Muenchen, HRB Nr. 43632 -- To unsubscribe from this list: send the line unsubscribe kvm in the body of a message to majord...@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html
Re: [PATCH 0/3] KVM: Introduce VCPU-wide notion of guest-mode V2
On Mon, Nov 29, 2010 at 05:51:46PM +0100, Joerg Roedel wrote: Hi Avi, Hi Marcelo, here is the re-spin I promised. The change to V1 are essentially the renames: kvm_vcpu_enter_gm - enter_guest_mode kvm_vcpu_leave_gm - leave_guest_mode kvm_vcpu_is_gm- is_guest_mode No other changes are in this patch-set compared to V1. Regards, Joerg arch/x86/include/asm/kvm_host.h |1 + arch/x86/kvm/kvm_cache_regs.h | 15 + arch/x86/kvm/svm.c | 44 ++ arch/x86/kvm/x86.c | 14 --- 4 files changed, 47 insertions(+), 27 deletions(-) Joerg Roedel (3): KVM: X86: Introduce generic guest-mode representation KVM: SVM: Make Use of the generic guest-mode functions KVM: X86: Don't report L2 emulation failures to user-space Applied, thanks. -- To unsubscribe from this list: send the line unsubscribe kvm in the body of a message to majord...@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html
[PATCH 0/3] KVM: Introduce VCPU-wide notion of guest-mode
Hi Avi, Hi Marcelo, this patch-set introduces a generic notion of guest-mode for VCPUs in KVM. This is already useful as seen in patch 3/3. Nested-VMX also has a guest-mode, so it will make sense for this code too. Regards, Joerg As usual: arch/x86/include/asm/kvm_host.h |1 + arch/x86/kvm/kvm_cache_regs.h | 15 + arch/x86/kvm/svm.c | 44 ++ arch/x86/kvm/x86.c | 14 --- Joerg Roedel (3): KVM: X86: Introduce generic guest-mode representation KVM: SVM: Make Use of the generic guest-mode functions KVM: X86: Don't report L2 emulation failures to user-space 4 files changed, 47 insertions(+), 27 deletions(-) -- To unsubscribe from this list: send the line unsubscribe kvm in the body of a message to majord...@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html
Re: [PATCH 0/3] KVM: Introduce VCPU-wide notion of guest-mode
On 11/29/2010 05:38 PM, Joerg Roedel wrote: Hi Avi, Hi Marcelo, this patch-set introduces a generic notion of guest-mode for VCPUs in KVM. This is already useful as seen in patch 3/3. Nested-VMX also has a guest-mode, so it will make sense for this code too. Looks good, apart from the trivial comments on patch 1. -- error compiling committee.c: too many arguments to function -- To unsubscribe from this list: send the line unsubscribe kvm in the body of a message to majord...@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html
Re: [PATCH 0/3] KVM: Introduce VCPU-wide notion of guest-mode
On Mon, Nov 29, 2010 at 11:10:59AM -0500, Avi Kivity wrote: On 11/29/2010 05:38 PM, Joerg Roedel wrote: Hi Avi, Hi Marcelo, this patch-set introduces a generic notion of guest-mode for VCPUs in KVM. This is already useful as seen in patch 3/3. Nested-VMX also has a guest-mode, so it will make sense for this code too. Looks good, apart from the trivial comments on patch 1. Okay, I do a re-spin and fix this. Thanks for your comments. Joerg -- AMD Operating System Research Center Advanced Micro Devices GmbH Einsteinring 24 85609 Dornach General Managers: Alberto Bozzo, Andrew Bowd Registration: Dornach, Landkr. Muenchen; Registerger. Muenchen, HRB Nr. 43632 -- To unsubscribe from this list: send the line unsubscribe kvm in the body of a message to majord...@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html
[PATCH 0/3] KVM: Introduce VCPU-wide notion of guest-mode V2
Hi Avi, Hi Marcelo, here is the re-spin I promised. The change to V1 are essentially the renames: kvm_vcpu_enter_gm - enter_guest_mode kvm_vcpu_leave_gm - leave_guest_mode kvm_vcpu_is_gm- is_guest_mode No other changes are in this patch-set compared to V1. Regards, Joerg arch/x86/include/asm/kvm_host.h |1 + arch/x86/kvm/kvm_cache_regs.h | 15 + arch/x86/kvm/svm.c | 44 ++ arch/x86/kvm/x86.c | 14 --- 4 files changed, 47 insertions(+), 27 deletions(-) Joerg Roedel (3): KVM: X86: Introduce generic guest-mode representation KVM: SVM: Make Use of the generic guest-mode functions KVM: X86: Don't report L2 emulation failures to user-space -- To unsubscribe from this list: send the line unsubscribe kvm in the body of a message to majord...@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html
