Re: [Bug 53611] New: nVMX: Add nested EPT
On 2013-04-26 18:07, Nakajima, Jun wrote: On Thu, Apr 25, 2013 at 11:26 PM, Jan Kiszka jan.kis...@web.de wrote: That's great but - as Gleb already said - unfortunately not yet usable. I'd like to rebase my fixes and enhancements (unrestricted guest mode specifically) on top these days, and also run some tests with a non-KVM guest. So, if git send-email is not yet working there, I would also be happy about a public git repository. I re-submitted the patches last night using git send-email this time. We had some email problems at that time, and I needed to use a workaround (imap-send) at that time (and it didn't work well). I've picked them up (except for Xinhao's follow-up patch) and rebased them over next + my pending patches: git://git.kiszka.org/linux-kvm.git queues/nept Some patches required a bit massaging to apply, and the last one had a trivial style issue. Feel free to integrate the changes. I didn't look into functional details yet. Instead, I've rebased my unrestricted guest mode patch plus a bunch of fixes around nEPT and that feature. See the branch above. I'm currently testing them, and it looks very good so far. Unrestricted guest mode speeds up L2's BIOS and boot loader phase noticeably. Jan signature.asc Description: OpenPGP digital signature
Re: [Bug 53611] New: nVMX: Add nested EPT
On 2013-04-25 10:00, Nakajima, Jun wrote: On Wed, Apr 24, 2013 at 8:55 AM, Nakajima, Jun jun.nakaj...@intel.com wrote: Sorry about the slow progress. We've been distracted by some priority things. The patches are ready (i.e. working), but we are cleaning them up. I'll send what we have today. So, I have sent them, and frankly we are still cleaning up. Please bear with us. We are also sending one more patchset to deal with EPT misconfiguration, but Linux should run in L2 on top of L1 KVM. That's great but - as Gleb already said - unfortunately not yet usable. I'd like to rebase my fixes and enhancements (unrestricted guest mode specifically) on top these days, and also run some tests with a non-KVM guest. So, if git send-email is not yet working there, I would also be happy about a public git repository. Thanks, Jan signature.asc Description: OpenPGP digital signature
Re: [Bug 53611] New: nVMX: Add nested EPT
On Thu, Apr 25, 2013 at 11:26 PM, Jan Kiszka jan.kis...@web.de wrote: That's great but - as Gleb already said - unfortunately not yet usable. I'd like to rebase my fixes and enhancements (unrestricted guest mode specifically) on top these days, and also run some tests with a non-KVM guest. So, if git send-email is not yet working there, I would also be happy about a public git repository. I re-submitted the patches last night using git send-email this time. We had some email problems at that time, and I needed to use a workaround (imap-send) at that time (and it didn't work well). -- Jun Intel Open Source Technology Center -- 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: [Bug 53611] New: nVMX: Add nested EPT
On Wed, Apr 24, 2013 at 8:55 AM, Nakajima, Jun jun.nakaj...@intel.com wrote: Sorry about the slow progress. We've been distracted by some priority things. The patches are ready (i.e. working), but we are cleaning them up. I'll send what we have today. So, I have sent them, and frankly we are still cleaning up. Please bear with us. We are also sending one more patchset to deal with EPT misconfiguration, but Linux should run in L2 on top of L1 KVM. -- Jun Intel Open Source Technology Center -- 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: [Bug 53611] New: nVMX: Add nested EPT
On Thu, Apr 25, 2013 at 01:00:42AM -0700, Nakajima, Jun wrote: On Wed, Apr 24, 2013 at 8:55 AM, Nakajima, Jun jun.nakaj...@intel.com wrote: Sorry about the slow progress. We've been distracted by some priority things. The patches are ready (i.e. working), but we are cleaning them up. I'll send what we have today. So, I have sent them, and frankly we are still cleaning up. Please bear with us. We are also sending one more patchset to deal with EPT misconfiguration, but Linux should run in L2 on top of L1 KVM. The patches are mangled and unreadable. Please resend using git send-email. -- Gleb. -- 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: [Bug 53611] New: nVMX: Add nested EPT
On 2013-03-22 17:45, Jan Kiszka wrote: On 2013-03-22 07:23, Nakajima, Jun wrote: On Mon, Mar 4, 2013 at 8:45 PM, Nakajima, Jun jun.nakaj...@intel.com wrote: I have some updates on this. We rebased the patched to the latest KVM (L0). It turned out that the version of L1 KVM/Linux matters. At that time, actually I used v3.7 kernel for L1, and the L2 didn't work as I described above. If I use v3.5 or older for L1, L2 works with the EPT patches. So, I guess some changes made to v3.6 might have exposed a bug with the nested EPT patches or somewhere. We are looking at the changes to root-cause it. Finally I've had more time to work on this, and I think I've fixed this. The problem was that the exit qualification for EPT violation (to L1) was not accurate (enough). And I needed to save the exit qualification upon EPT violation somewhere. Today, that information is converted to error_code (see below), and we lose the information. We need to use at least the lower 3 bits when injecting EPT violation to the L1 VMM. I tried to use the upper bytes of error_code to pass part of the exit qualification, but it didn't work well. Any suggestion for the place to store the value? kvm_vcpu? ... /* It is a write fault? */ error_code = exit_qualification (1U 1); /* ept page table is present? */ error_code |= (exit_qualification 3) 0x1; return kvm_mmu_page_fault(vcpu, gpa, error_code, NULL, 0); I don't have a full picture (already asked you to post / git-push your intermediate state), but nested related states typically go to nested_vmx, thus vcpu_vmx. Ping regarding publication. I'm about to redo your porting work as we are making no progress. Jan signature.asc Description: OpenPGP digital signature
Re: [Bug 53611] New: nVMX: Add nested EPT
On Wed, Apr 24, 2013 at 12:25 AM, Jan Kiszka jan.kis...@web.de wrote: I don't have a full picture (already asked you to post / git-push your intermediate state), but nested related states typically go to nested_vmx, thus vcpu_vmx. Ping regarding publication. I'm about to redo your porting work as we are making no progress. Sorry about the slow progress. We've been distracted by some priority things. The patches are ready (i.e. working), but we are cleaning them up. I'll send what we have today. -- Jun Intel Open Source Technology Center -- 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: [Bug 53611] New: nVMX: Add nested EPT
On 2013-04-24 17:55, Nakajima, Jun wrote: On Wed, Apr 24, 2013 at 12:25 AM, Jan Kiszka jan.kis...@web.de wrote: I don't have a full picture (already asked you to post / git-push your intermediate state), but nested related states typically go to nested_vmx, thus vcpu_vmx. Ping regarding publication. I'm about to redo your porting work as we are making no progress. Sorry about the slow progress. We've been distracted by some priority things. The patches are ready (i.e. working), but we are cleaning them up. I'll send what we have today. Great news, thanks a lot! Jan signature.asc Description: OpenPGP digital signature
Re: [Bug 53611] New: nVMX: Add nested EPT
On Mon, Mar 4, 2013 at 8:45 PM, Nakajima, Jun jun.nakaj...@intel.com wrote: I have some updates on this. We rebased the patched to the latest KVM (L0). It turned out that the version of L1 KVM/Linux matters. At that time, actually I used v3.7 kernel for L1, and the L2 didn't work as I described above. If I use v3.5 or older for L1, L2 works with the EPT patches. So, I guess some changes made to v3.6 might have exposed a bug with the nested EPT patches or somewhere. We are looking at the changes to root-cause it. Finally I've had more time to work on this, and I think I've fixed this. The problem was that the exit qualification for EPT violation (to L1) was not accurate (enough). And I needed to save the exit qualification upon EPT violation somewhere. Today, that information is converted to error_code (see below), and we lose the information. We need to use at least the lower 3 bits when injecting EPT violation to the L1 VMM. I tried to use the upper bytes of error_code to pass part of the exit qualification, but it didn't work well. Any suggestion for the place to store the value? kvm_vcpu? ... /* It is a write fault? */ error_code = exit_qualification (1U 1); /* ept page table is present? */ error_code |= (exit_qualification 3) 0x1; return kvm_mmu_page_fault(vcpu, gpa, error_code, NULL, 0); -- Jun Intel Open Source Technology Center -- 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: [Bug 53611] New: nVMX: Add nested EPT
On 2013-03-22 07:23, Nakajima, Jun wrote: On Mon, Mar 4, 2013 at 8:45 PM, Nakajima, Jun jun.nakaj...@intel.com wrote: I have some updates on this. We rebased the patched to the latest KVM (L0). It turned out that the version of L1 KVM/Linux matters. At that time, actually I used v3.7 kernel for L1, and the L2 didn't work as I described above. If I use v3.5 or older for L1, L2 works with the EPT patches. So, I guess some changes made to v3.6 might have exposed a bug with the nested EPT patches or somewhere. We are looking at the changes to root-cause it. Finally I've had more time to work on this, and I think I've fixed this. The problem was that the exit qualification for EPT violation (to L1) was not accurate (enough). And I needed to save the exit qualification upon EPT violation somewhere. Today, that information is converted to error_code (see below), and we lose the information. We need to use at least the lower 3 bits when injecting EPT violation to the L1 VMM. I tried to use the upper bytes of error_code to pass part of the exit qualification, but it didn't work well. Any suggestion for the place to store the value? kvm_vcpu? ... /* It is a write fault? */ error_code = exit_qualification (1U 1); /* ept page table is present? */ error_code |= (exit_qualification 3) 0x1; return kvm_mmu_page_fault(vcpu, gpa, error_code, NULL, 0); I don't have a full picture (already asked you to post / git-push your intermediate state), but nested related states typically go to nested_vmx, thus vcpu_vmx. Jan -- Siemens AG, Corporate Technology, CT RTC ITP SDP-DE Corporate Competence Center Embedded Linux -- 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: [Bug 53611] New: nVMX: Add nested EPT
On 2013-03-05 05:45, Nakajima, Jun wrote: On Tue, Feb 26, 2013 at 11:43 AM, Jan Kiszka jan.kis...@web.de wrote: On 2013-02-26 15:11, Nadav Har'El wrote: On Thu, Feb 14, 2013, Nakajima, Jun wrote about Re: [Bug 53611] New: nVMX: Add nested EPT: We have started looking at the pataches first. But I couldn't reproduce the results by simply applying the original patches to v3.6: - L2 Ubuntu 12.04 (64-bit) (smp 2) - L1 Ubuntu 12.04 (64-bit) KVM (smp 2) - L0 Ubuntu 12.04 (64-bit)-based. kernel/KVM is v3.6 + patches (the ones in nept-v2.tgz). https://bugzilla.kernel.org/attachment.cgi?id=93101 Without the patches, the L2 guest works. With it, it hangs at boot time (just black screen): - EPT was detected by L1 KVM. - UP L2 didn't help. - Looks like it's looping at EPT_walk_add_generic at the same address in L0. Will take a closer look. It would be helpful if the test configuration (e.g kernel/commit id used, L1/L2 guests) was documented as well. I sent the patches in August 1st, and they applied to commit ade38c311a0ad8c32e902fe1d0ae74d0d44bc71e from a week earlier. In most of my tests, L1 and L2 were old images - L1 had Linux 2.6.33, while L2 had Linux 2.6.28. In most of my tests both L1 and L2 were UP. I've heard another report of my patch not working with newer L1/L2 - the report said that L2 failed to boot (like you reported), and also that L1 became unstable (running anything in it gave a memory fault). So it is very likely that this code still has bugs - but since I already know of errors and holes that need to be plugged (see the announcement file together with the patches), it's not very surprising :( These patches definitely need some lovin', but it's easier than starting from scratch. FWIW, I'm playing with them on top of kvm-3.6-2 (second pull request for 3.6) for a while. They work OK for my use case (static mapping) but apparently lock up L2 when starting KVM on KVM, just as reported. I didn't look into any details there, still busy with fixing other issues like CR0/CR4 handling (which I came across while adding unrestricted guest support on top of EPT). I have some updates on this. We rebased the patched to the latest KVM (L0). It turned out that the version of L1 KVM/Linux matters. At that time, actually I used v3.7 kernel for L1, and the L2 didn't work as I described above. If I use v3.5 or older for L1, L2 works with the EPT patches. So, I guess some changes made to v3.6 might have exposed a bug with the nested EPT patches or somewhere. We are looking at the changes to root-cause it. Great to hear! Would you mind to share your work early, even when it's not yet stable? At least regarding lockups or misbehaviors of L1 and L2, some of the patches I posted recently may help. Did you try to merge them as well? Thanks, Jan signature.asc Description: OpenPGP digital signature
Re: [Bug 53611] New: nVMX: Add nested EPT
On Tue, Feb 26, 2013 at 11:43 AM, Jan Kiszka jan.kis...@web.de wrote: On 2013-02-26 15:11, Nadav Har'El wrote: On Thu, Feb 14, 2013, Nakajima, Jun wrote about Re: [Bug 53611] New: nVMX: Add nested EPT: We have started looking at the pataches first. But I couldn't reproduce the results by simply applying the original patches to v3.6: - L2 Ubuntu 12.04 (64-bit) (smp 2) - L1 Ubuntu 12.04 (64-bit) KVM (smp 2) - L0 Ubuntu 12.04 (64-bit)-based. kernel/KVM is v3.6 + patches (the ones in nept-v2.tgz). https://bugzilla.kernel.org/attachment.cgi?id=93101 Without the patches, the L2 guest works. With it, it hangs at boot time (just black screen): - EPT was detected by L1 KVM. - UP L2 didn't help. - Looks like it's looping at EPT_walk_add_generic at the same address in L0. Will take a closer look. It would be helpful if the test configuration (e.g kernel/commit id used, L1/L2 guests) was documented as well. I sent the patches in August 1st, and they applied to commit ade38c311a0ad8c32e902fe1d0ae74d0d44bc71e from a week earlier. In most of my tests, L1 and L2 were old images - L1 had Linux 2.6.33, while L2 had Linux 2.6.28. In most of my tests both L1 and L2 were UP. I've heard another report of my patch not working with newer L1/L2 - the report said that L2 failed to boot (like you reported), and also that L1 became unstable (running anything in it gave a memory fault). So it is very likely that this code still has bugs - but since I already know of errors and holes that need to be plugged (see the announcement file together with the patches), it's not very surprising :( These patches definitely need some lovin', but it's easier than starting from scratch. FWIW, I'm playing with them on top of kvm-3.6-2 (second pull request for 3.6) for a while. They work OK for my use case (static mapping) but apparently lock up L2 when starting KVM on KVM, just as reported. I didn't look into any details there, still busy with fixing other issues like CR0/CR4 handling (which I came across while adding unrestricted guest support on top of EPT). I have some updates on this. We rebased the patched to the latest KVM (L0). It turned out that the version of L1 KVM/Linux matters. At that time, actually I used v3.7 kernel for L1, and the L2 didn't work as I described above. If I use v3.5 or older for L1, L2 works with the EPT patches. So, I guess some changes made to v3.6 might have exposed a bug with the nested EPT patches or somewhere. We are looking at the changes to root-cause it. Given that I'm porting now patches between that branch and next back and forth (I depend on EPT), it would be really great if someone familiar with the KVM MMU (or enough time) could port the series to the current git head. That would not solve remaining bugs but could trigger more development, maybe also help me jumping into this. Thanks, Jan -- Jun Intel Open Source Technology Center -- 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: [Bug 53611] New: nVMX: Add nested EPT
On Thu, Feb 14, 2013, Nakajima, Jun wrote about Re: [Bug 53611] New: nVMX: Add nested EPT: We have started looking at the pataches first. But I couldn't reproduce the results by simply applying the original patches to v3.6: - L2 Ubuntu 12.04 (64-bit) (smp 2) - L1 Ubuntu 12.04 (64-bit) KVM (smp 2) - L0 Ubuntu 12.04 (64-bit)-based. kernel/KVM is v3.6 + patches (the ones in nept-v2.tgz). https://bugzilla.kernel.org/attachment.cgi?id=93101 Without the patches, the L2 guest works. With it, it hangs at boot time (just black screen): - EPT was detected by L1 KVM. - UP L2 didn't help. - Looks like it's looping at EPT_walk_add_generic at the same address in L0. Will take a closer look. It would be helpful if the test configuration (e.g kernel/commit id used, L1/L2 guests) was documented as well. I sent the patches in August 1st, and they applied to commit ade38c311a0ad8c32e902fe1d0ae74d0d44bc71e from a week earlier. In most of my tests, L1 and L2 were old images - L1 had Linux 2.6.33, while L2 had Linux 2.6.28. In most of my tests both L1 and L2 were UP. I've heard another report of my patch not working with newer L1/L2 - the report said that L2 failed to boot (like you reported), and also that L1 became unstable (running anything in it gave a memory fault). So it is very likely that this code still has bugs - but since I already know of errors and holes that need to be plugged (see the announcement file together with the patches), it's not very surprising :( These patches definitely need some lovin', but it's easier than starting from scratch. Nadav. -- Nadav Har'El| Tuesday, Feb 26 2013, 16 Adar 5773 n...@math.technion.ac.il |- Phone +972-523-790466, ICQ 13349191 |I think therefore I am. My computer http://nadav.harel.org.il |thinks for me, therefore I am not. -- 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: [Bug 53611] New: nVMX: Add nested EPT
On 2013-02-26 15:11, Nadav Har'El wrote: On Thu, Feb 14, 2013, Nakajima, Jun wrote about Re: [Bug 53611] New: nVMX: Add nested EPT: We have started looking at the pataches first. But I couldn't reproduce the results by simply applying the original patches to v3.6: - L2 Ubuntu 12.04 (64-bit) (smp 2) - L1 Ubuntu 12.04 (64-bit) KVM (smp 2) - L0 Ubuntu 12.04 (64-bit)-based. kernel/KVM is v3.6 + patches (the ones in nept-v2.tgz). https://bugzilla.kernel.org/attachment.cgi?id=93101 Without the patches, the L2 guest works. With it, it hangs at boot time (just black screen): - EPT was detected by L1 KVM. - UP L2 didn't help. - Looks like it's looping at EPT_walk_add_generic at the same address in L0. Will take a closer look. It would be helpful if the test configuration (e.g kernel/commit id used, L1/L2 guests) was documented as well. I sent the patches in August 1st, and they applied to commit ade38c311a0ad8c32e902fe1d0ae74d0d44bc71e from a week earlier. In most of my tests, L1 and L2 were old images - L1 had Linux 2.6.33, while L2 had Linux 2.6.28. In most of my tests both L1 and L2 were UP. I've heard another report of my patch not working with newer L1/L2 - the report said that L2 failed to boot (like you reported), and also that L1 became unstable (running anything in it gave a memory fault). So it is very likely that this code still has bugs - but since I already know of errors and holes that need to be plugged (see the announcement file together with the patches), it's not very surprising :( These patches definitely need some lovin', but it's easier than starting from scratch. FWIW, I'm playing with them on top of kvm-3.6-2 (second pull request for 3.6) for a while. They work OK for my use case (static mapping) but apparently lock up L2 when starting KVM on KVM, just as reported. I didn't look into any details there, still busy with fixing other issues like CR0/CR4 handling (which I came across while adding unrestricted guest support on top of EPT). Given that I'm porting now patches between that branch and next back and forth (I depend on EPT), it would be really great if someone familiar with the KVM MMU (or enough time) could port the series to the current git head. That would not solve remaining bugs but could trigger more development, maybe also help me jumping into this. Thanks, Jan signature.asc Description: OpenPGP digital signature
Re: [Bug 53611] New: nVMX: Add nested EPT
On Tue, Feb 26, 2013 at 08:43:13PM +0100, Jan Kiszka wrote: On 2013-02-26 15:11, Nadav Har'El wrote: On Thu, Feb 14, 2013, Nakajima, Jun wrote about Re: [Bug 53611] New: nVMX: Add nested EPT: We have started looking at the pataches first. But I couldn't reproduce the results by simply applying the original patches to v3.6: - L2 Ubuntu 12.04 (64-bit) (smp 2) - L1 Ubuntu 12.04 (64-bit) KVM (smp 2) - L0 Ubuntu 12.04 (64-bit)-based. kernel/KVM is v3.6 + patches (the ones in nept-v2.tgz). https://bugzilla.kernel.org/attachment.cgi?id=93101 Without the patches, the L2 guest works. With it, it hangs at boot time (just black screen): - EPT was detected by L1 KVM. - UP L2 didn't help. - Looks like it's looping at EPT_walk_add_generic at the same address in L0. Will take a closer look. It would be helpful if the test configuration (e.g kernel/commit id used, L1/L2 guests) was documented as well. I sent the patches in August 1st, and they applied to commit ade38c311a0ad8c32e902fe1d0ae74d0d44bc71e from a week earlier. In most of my tests, L1 and L2 were old images - L1 had Linux 2.6.33, while L2 had Linux 2.6.28. In most of my tests both L1 and L2 were UP. I've heard another report of my patch not working with newer L1/L2 - the report said that L2 failed to boot (like you reported), and also that L1 became unstable (running anything in it gave a memory fault). So it is very likely that this code still has bugs - but since I already know of errors and holes that need to be plugged (see the announcement file together with the patches), it's not very surprising :( These patches definitely need some lovin', but it's easier than starting from scratch. FWIW, I'm playing with them on top of kvm-3.6-2 (second pull request for 3.6) for a while. They work OK for my use case (static mapping) but apparently lock up L2 when starting KVM on KVM, just as reported. I didn't look into any details there, still busy with fixing other issues like CR0/CR4 handling (which I came across while adding unrestricted guest support on top of EPT). Given that I'm porting now patches between that branch and next back and forth (I depend on EPT), it would be really great if someone familiar with the KVM MMU (or enough time) could port the series to the current git head. That would not solve remaining bugs but could trigger more development, maybe also help me jumping into this. I'd like to do that. See if I'll have time... -- Gleb. -- 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: [Bug 53611] New: nVMX: Add nested EPT
On Tue, Feb 12, 2013 at 11:43 PM, Jan Kiszka jan.kis...@siemens.com wrote: On 2013-02-12 20:13, Nakajima, Jun wrote: I looked at your (old) patches, and they seem to be very useful although some of them require rebasing or rewriting. We are interested in completing the nested-VMX features. That's great news. Can you estimate when you will be able to work on it? We have started looking at the pataches first. But I couldn't reproduce the results by simply applying the original patches to v3.6: - L2 Ubuntu 12.04 (64-bit) (smp 2) - L1 Ubuntu 12.04 (64-bit) KVM (smp 2) - L0 Ubuntu 12.04 (64-bit)-based. kernel/KVM is v3.6 + patches (the ones in nept-v2.tgz). https://bugzilla.kernel.org/attachment.cgi?id=93101 Without the patches, the L2 guest works. With it, it hangs at boot time (just black screen): - EPT was detected by L1 KVM. - UP L2 didn't help. - Looks like it's looping at EPT_walk_add_generic at the same address in L0. Will take a closer look. It would be helpful if the test configuration (e.g kernel/commit id used, L1/L2 guests) was documented as well. I will have a use case for nEPT soon - testing purposes. But working into the KVM MMU and doing the port myself may unfortunately consume too much time here. Jan -- Jun Intel Open Source Technology Center -- 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: [Bug 53611] New: nVMX: Add nested EPT
On Mon, Feb 11, 2013 at 5:27 AM, Nadav Har'El n...@math.technion.ac.il wrote: Hi, On Mon, Feb 11, 2013, Jan Kiszka wrote about Re: [Bug 53611] New: nVMX: Add nested EPT: On 2013-02-11 13:49, bugzilla-dae...@bugzilla.kernel.org wrote: https://bugzilla.kernel.org/show_bug.cgi?id=53611 Summary: nVMX: Add nested EPT Yikes, I didn't realize that these bugzilla edits all get spammed to the entire mailing list :( Sorry about those... I suppose they do not apply anymore as well. Do you have a recent tree around somewhere or plan to resume work on it? Unfortunately, no - I did not have time to work on these patches since August. The reason I'm now stuffing these things into the bug tracker is that at the end of this month I am leaving IBM to a new job, so I'm pretty sure I won't have time myself to continue any work on nested VMX, and would like for the missing nested-VMX features to be documented in case someone else comes along and wants to improve it. So unfortunately, you should expect more of this bugzilla spam on the mailing list... I looked at your (old) patches, and they seem to be very useful although some of them require rebasing or rewriting. We are interested in completing the nested-VMX features. -- Jun Intel Open Source Technology Center -- 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: [Bug 53611] New: nVMX: Add nested EPT
On 2013-02-12 20:13, Nakajima, Jun wrote: On Mon, Feb 11, 2013 at 5:27 AM, Nadav Har'El n...@math.technion.ac.il wrote: Hi, On Mon, Feb 11, 2013, Jan Kiszka wrote about Re: [Bug 53611] New: nVMX: Add nested EPT: On 2013-02-11 13:49, bugzilla-dae...@bugzilla.kernel.org wrote: https://bugzilla.kernel.org/show_bug.cgi?id=53611 Summary: nVMX: Add nested EPT Yikes, I didn't realize that these bugzilla edits all get spammed to the entire mailing list :( Sorry about those... I suppose they do not apply anymore as well. Do you have a recent tree around somewhere or plan to resume work on it? Unfortunately, no - I did not have time to work on these patches since August. The reason I'm now stuffing these things into the bug tracker is that at the end of this month I am leaving IBM to a new job, so I'm pretty sure I won't have time myself to continue any work on nested VMX, and would like for the missing nested-VMX features to be documented in case someone else comes along and wants to improve it. So unfortunately, you should expect more of this bugzilla spam on the mailing list... I looked at your (old) patches, and they seem to be very useful although some of them require rebasing or rewriting. We are interested in completing the nested-VMX features. That's great news. Can you estimate when you will be able to work on it? I will have a use case for nEPT soon - testing purposes. But working into the KVM MMU and doing the port myself may unfortunately consume too much time here. Jan -- Siemens AG, Corporate Technology, CT RTC ITP SDP-DE Corporate Competence Center Embedded Linux -- 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: [Bug 53611] New: nVMX: Add nested EPT
On 2013-02-11 13:49, bugzilla-dae...@bugzilla.kernel.org wrote: https://bugzilla.kernel.org/show_bug.cgi?id=53611 Summary: nVMX: Add nested EPT Product: Virtualization Version: unspecified Platform: All OS/Version: Linux Tree: Mainline Status: NEW Severity: normal Priority: P1 Component: kvm AssignedTo: virtualization_...@kernel-bugs.osdl.org ReportedBy: n...@math.technion.ac.il Regression: No Created an attachment (id=93101) -- (https://bugzilla.kernel.org/attachment.cgi?id=93101) Nested EPT patches, v2 Nested EPT means emulating EPT for an L1 guest, allowing it to use EPT when running a nested guest L2. When L1 uses EPT, it allows the L2 guest to set its own cr3 and take its own page faults without either of L0 or L1 getting involved. In many workloads this significanlty improves L2's performance over the previous two alternatives (shadow page tables over ept, and shadow page tables over shadow page tables). As an example, I measured a single-threaded make, which has a lot of context switches and page faults, on the three options: shadow over shadow: 105 seconds shadow over EPT: 87 seconds (this is the default currently) EPT over EPT: 29 seconds single-level virtualization (with EPT): 25 seconds So clearly nested EPT would be a big win for such workloads. I attach a patch set which I worked on and allowed me to measure the above results. This is the same patch set I sent to KVM mailing list on August 1st, 2012, titled nEPT v2: Nested EPT support for Nested VMX. This patch set still needs some work: it is known to only work in some setups but not others, and the file announce in the attached tar lists 5 things which definitely need to be done. There were a few additional comments in the mailing list - see http://comments.gmane.org/gmane.comp.emulators.kvm.devel/95395 I suppose they do not apply anymore as well. Do you have a recent tree around somewhere or plan to resume work on it? Jan -- Siemens AG, Corporate Technology, CT RTC ITP SDP-DE Corporate Competence Center Embedded Linux -- 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: [Bug 53611] New: nVMX: Add nested EPT
Hi, On Mon, Feb 11, 2013, Jan Kiszka wrote about Re: [Bug 53611] New: nVMX: Add nested EPT: On 2013-02-11 13:49, bugzilla-dae...@bugzilla.kernel.org wrote: https://bugzilla.kernel.org/show_bug.cgi?id=53611 Summary: nVMX: Add nested EPT Yikes, I didn't realize that these bugzilla edits all get spammed to the entire mailing list :( Sorry about those... I suppose they do not apply anymore as well. Do you have a recent tree around somewhere or plan to resume work on it? Unfortunately, no - I did not have time to work on these patches since August. The reason I'm now stuffing these things into the bug tracker is that at the end of this month I am leaving IBM to a new job, so I'm pretty sure I won't have time myself to continue any work on nested VMX, and would like for the missing nested-VMX features to be documented in case someone else comes along and wants to improve it. So unfortunately, you should expect more of this bugzilla spam on the mailing list... Nadav. -- Nadav Har'El| Monday, Feb 11 2013, 1 Adar 5773 n...@math.technion.ac.il |- Phone +972-523-790466, ICQ 13349191 |The message above is just this http://nadav.harel.org.il |signature's way of propagating itself. -- 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: [Bug 53611] New: nVMX: Add nested EPT
On 2013-02-11 14:27, Nadav Har'El wrote: Hi, On Mon, Feb 11, 2013, Jan Kiszka wrote about Re: [Bug 53611] New: nVMX: Add nested EPT: On 2013-02-11 13:49, bugzilla-dae...@bugzilla.kernel.org wrote: https://bugzilla.kernel.org/show_bug.cgi?id=53611 Summary: nVMX: Add nested EPT Yikes, I didn't realize that these bugzilla edits all get spammed to the entire mailing list :( Sorry about those... I suppose they do not apply anymore as well. Do you have a recent tree around somewhere or plan to resume work on it? Unfortunately, no - I did not have time to work on these patches since August. The reason I'm now stuffing these things into the bug tracker is that at the end of this month I am leaving IBM to a new job, so I'm pretty sure I won't have time myself to continue any work on nested VMX, and would like for the missing nested-VMX features to be documented in case someone else comes along and wants to improve it. So unfortunately, you should expect more of this bugzilla spam on the mailing list... A pity that you cannot finish this great work. But documenting the open issues is definitely helpful and welcome. Best wishes, Jan -- Siemens AG, Corporate Technology, CT RTC ITP SDP-DE Corporate Competence Center Embedded Linux -- 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
