| Message ID | 1247703135-27408-2-git-send-email-jordan.l.justen@intel.com (mailing list archive) |
|---|---|
| State | New, archived |
| Headers | show |
On Thursday 16 July 2009 08:12:15 Jordan Justen wrote: > Previously the KVM kernel module would allocate the address range > of 0xfffbc000-0xfffbcfff for the EPT Indentity Page Tables. > A separate patch is moving that to 0xfeffc000-0xfeffcfff. Hi Jordan You need one more patch for upstream kvm, to include the modification of vmx.h. > > This patch updates qemu-kvm to move the VMX TSS Pages & update the > KVM BIOS code to update the E820 BIOS call memory reservations. > > Previously, the VMC TSS Pages were located at 0xfffbd000-0xfffbffff. > This change moved them to 0xfeffd000-0xfeffffff. > > This change also updates the KVM bios such that the E820 locations > are returned properly for these two changes. > > From a high level, these are the effects of these two changes: > > Previously, the KVM would only accommodate a 256KB BIOS image. With > these changes, the BIOS image may now grow to 16MB. > > Motivation for making these changes: > > A larger firmware image size allows alternative BIOS images to be > used with KVM. Some possible uses are to enable UEFI firmware > or coreboot firmware. Additionally, an alternative firmware might > include a linux kernel+initrd payload, which would require several > megabytes. I think if you update bios to UEFI, the E820 should be represented by UEFI rather than current bios?
On Wed, Jul 15, 2009 at 6:34 PM, Sheng Yang <sheng@linux.intel.com> wrote: > > On Thursday 16 July 2009 08:12:15 Jordan Justen wrote: > > Previously the KVM kernel module would allocate the address range > > of 0xfffbc000-0xfffbcfff for the EPT Indentity Page Tables. > > A separate patch is moving that to 0xfeffc000-0xfeffcfff. > > Hi Jordan > > You need one more patch for upstream kvm, to include the modification of > vmx.h. I sent a separate patch for vmx.h for the git://git.kernel.org/pub/scm/virt/kvm/kvm.git tree. Do I need a patch for another copy of vmx.h? > > > > This patch updates qemu-kvm to move the VMX TSS Pages & update the > > KVM BIOS code to update the E820 BIOS call memory reservations. > > > > Previously, the VMC TSS Pages were located at 0xfffbd000-0xfffbffff. > > This change moved them to 0xfeffd000-0xfeffffff. > > > > This change also updates the KVM bios such that the E820 locations > > are returned properly for these two changes. > > > > From a high level, these are the effects of these two changes: > > > > Previously, the KVM would only accommodate a 256KB BIOS image.  With > > these changes, the BIOS image may now grow to 16MB. > > > > Motivation for making these changes: > > > > A larger firmware image size allows alternative BIOS images to be > > used with KVM.  Some possible uses are to enable UEFI firmware > > or coreboot firmware.  Additionally, an alternative firmware might > > include a linux kernel+initrd payload, which would require several > > megabytes. > > I think if you update bios to UEFI, the E820 should be represented by UEFI > rather than current bios? Yeah, that is true. But, that firmware would be separate from the qemu-kvm tree at this time, right? But, in this patch it is critical that the 'VMX TSS Pages' are moved within qemu-kvm so the conflict with the larger bios.bin is removed. > > -- > regards > Yang, Sheng > > > Signed-off-by: Jordan Justen <jordan.l.justen@intel.com> > > --- > >  kvm/bios/rombios.c     |   8 ++++---- > >  kvm/include/x86/asm/vmx.h |   2 +- > >  qemu-kvm-x86.c       |   2 +- > >  3 files changed, 6 insertions(+), 6 deletions(-) > > > > diff --git a/kvm/bios/rombios.c b/kvm/bios/rombios.c > > index 6186199..2d0c153 100644 > > --- a/kvm/bios/rombios.c > > +++ b/kvm/bios/rombios.c > > @@ -4596,14 +4596,14 @@ ASM_END > >            case 5: > >              /* 4 pages before the bios, 3 pages for vmx tss > > pages, * the other page for EPT real mode pagetable */ > > -             set_e820_range(ES, regs.u.r16.di, 0xfffbc000L, > > -                    0xfffc0000L, 0, 0, 2); > > +             set_e820_range(ES, regs.u.r16.di, 0xfeffc000L, > > +                    0xff000000L, 0, 0, 2); > >              regs.u.r32.ebx = 6; > >              break; > >            case 6: > > -             /* 256KB BIOS area at the end of 4 GB */ > > +             /* 16MB BIOS area at the end of 4 GB */ > >              set_e820_range(ES, regs.u.r16.di, > > -                    0xfffc0000L, 0x00000000L ,0, 0, 2); > > +                    0xff000000L, 0x00000000L ,0, 0, 2); > >              if (extra_highbits_memory_size || > > extra_lowbits_memory_size) regs.u.r32.ebx = 7; > >              else > > diff --git a/kvm/include/x86/asm/vmx.h b/kvm/include/x86/asm/vmx.h > > index df8d4f9..99e2bb9 100644 > > --- a/kvm/include/x86/asm/vmx.h > > +++ b/kvm/include/x86/asm/vmx.h > > @@ -403,7 +403,7 @@ enum vmcs_field { > >  #define VMX_EPT_EXECUTABLE_MASK            0x4ull > >  #define VMX_EPT_IGMT_BIT           (1ull << 6) > > > > -#define VMX_EPT_IDENTITY_PAGETABLE_ADDR        0xfffbc000ul > > +#define VMX_EPT_IDENTITY_PAGETABLE_ADDR        0xfeffc000ul > > > > > >  #define ASM_VMX_VMCLEAR_RAX    ".byte 0x66, 0x0f, 0xc7, 0x30" > > diff --git a/qemu-kvm-x86.c b/qemu-kvm-x86.c > > index daf60b6..b5306aa 100644 > > --- a/qemu-kvm-x86.c > > +++ b/qemu-kvm-x86.c > > @@ -63,7 +63,7 @@ static int kvm_init_tss(kvm_context_t kvm) > >         * this address is 3 pages before the bios, and the bios should present > >         * as unavaible memory > >         */ > > -       r = kvm_set_tss_addr(kvm, 0xfffbd000); > > +       r = kvm_set_tss_addr(kvm, 0xfeffd000); > >        if (r < 0) { > >            fprintf(stderr, "kvm_init_tss: unable to set tss addr\n"); > >            return r; > > > -- > To unsubscribe from this list: send the line "unsubscribe kvm" in > the body of a message to majordomo@vger.kernel.org > More majordomo info at  http://vger.kernel.org/majordomo-info.html -- To unsubscribe from this list: send the line "unsubscribe kvm" in the body of a message to majordomo@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html
On Thursday 16 July 2009 10:58:53 Jordan Justen wrote: > On Wed, Jul 15, 2009 at 6:34 PM, Sheng Yang <sheng@linux.intel.com> wrote: > > On Thursday 16 July 2009 08:12:15 Jordan Justen wrote: > > > Previously the KVM kernel module would allocate the address range > > > of 0xfffbc000-0xfffbcfff for the EPT Indentity Page Tables. > > > A separate patch is moving that to 0xfeffc000-0xfeffcfff. > > > > Hi Jordan > > > > You need one more patch for upstream kvm, to include the modification of > > vmx.h. > > I sent a separate patch for vmx.h for the > git://git.kernel.org/pub/scm/virt/kvm/kvm.git tree. Do I > need a patch for another copy of vmx.h? Oh, sorry, overlook that one...(I just think the second one is a update to the first...) :( > > > > This patch updates qemu-kvm to move the VMX TSS Pages & update the > > > KVM BIOS code to update the E820 BIOS call memory reservations. > > > > > > Previously, the VMC TSS Pages were located at 0xfffbd000-0xfffbffff. > > > This change moved them to 0xfeffd000-0xfeffffff. > > > > > > This change also updates the KVM bios such that the E820 locations > > > are returned properly for these two changes. > > > > > > From a high level, these are the effects of these two changes: > > > > > > Previously, the KVM would only accommodate a 256KB BIOS image. With > > > these changes, the BIOS image may now grow to 16MB. > > > > > > Motivation for making these changes: > > > > > > A larger firmware image size allows alternative BIOS images to be > > > used with KVM. Some possible uses are to enable UEFI firmware > > > or coreboot firmware. Additionally, an alternative firmware might > > > include a linux kernel+initrd payload, which would require several > > > megabytes. > > > > I think if you update bios to UEFI, the E820 should be represented by > > UEFI rather than current bios? > > Yeah, that is true. But, that firmware would be separate from the qemu-kvm > tree at this time, right? Yes, so currently from QEmu-kvm side, I think it may not necessary to update, for the patches haven't followed up yet... > > But, in this patch it is critical that the 'VMX TSS Pages' are moved within > qemu-kvm so the conflict with the larger bios.bin is removed. Well, for we are using a small size bios now, and larger bios would be totally another story, I don't think push the modification now to the upstream make sense. These modification can go with further patches with UEFI at any time in the future.
On Wed, Jul 15, 2009 at 8:08 PM, Sheng Yang<sheng@linux.intel.com> wrote: > On Thursday 16 July 2009 10:58:53 Jordan Justen wrote: >> On Wed, Jul 15, 2009 at 6:34 PM, Sheng Yang <sheng@linux.intel.com> wrote: >> > On Thursday 16 July 2009 08:12:15 Jordan Justen wrote: >> > > >> > > Motivation for making these changes: >> > > >> > > A larger firmware image size allows alternative BIOS images to be >> > > used with KVM.  Some possible uses are to enable UEFI firmware >> > > or coreboot firmware.  Additionally, an alternative firmware might >> > > include a linux kernel+initrd payload, which would require several >> > > megabytes. >> > >> > I think if you update bios to UEFI, the E820 should be represented by >> > UEFI rather than current bios? >> >> Yeah, that is true.  But, that firmware would be separate from the qemu-kvm >> tree at this time, right? > > Yes, so currently from QEmu-kvm side, I think it may not necessary to update, > for the patches haven't followed up yet... Of the two patches (1. kvm kernel module, 2. qemu-kvm), I think it is best if the qemu-kvm change happens first. Since the qemu-kvm patch will cause the qemu-kvm bios to add more memory regions as reserved, the new change to qemu-kvm will be compatible with both the old and new versions of the kvm kernel module. >> But, in this patch it is critical that the 'VMX TSS Pages' are moved within >> qemu-kvm so the conflict with the larger bios.bin is removed. > > Well, for we are using a small size bios now, and larger bios would be totally > another story, I don't think push the modification now to the upstream make > sense. These modification can go with further patches with UEFI at any time in > the future. I am working on this UEFI firmware project which currently supports QEMU: https://edk2.tianocore.org/OVMF.html I would like it to also support KVM, and I found that it can already boot the UEFI shell on KVM if these two patches are applied. If these patches make some progress, I will update OVMF to reserve the appropriate memory regions. > -- > regards > Yang, Sheng > >> >> > -- >> > regards >> > Yang, Sheng >> > >> > > Signed-off-by: Jordan Justen <jordan.l.justen@intel.com> >> > > --- >> > >  kvm/bios/rombios.c     |   8 ++++---- >> > >  kvm/include/x86/asm/vmx.h |   2 +- >> > >  qemu-kvm-x86.c       |   2 +- >> > >  3 files changed, 6 insertions(+), 6 deletions(-) >> > > >> > > diff --git a/kvm/bios/rombios.c b/kvm/bios/rombios.c >> > > index 6186199..2d0c153 100644 >> > > --- a/kvm/bios/rombios.c >> > > +++ b/kvm/bios/rombios.c >> > > @@ -4596,14 +4596,14 @@ ASM_END >> > >            case 5: >> > >              /* 4 pages before the bios, 3 pages for vmx >> > > tss pages, * the other page for EPT real mode pagetable */ >> > > -             set_e820_range(ES, regs.u.r16.di, 0xfffbc000L, >> > > -                    0xfffc0000L, 0, 0, 2); >> > > +             set_e820_range(ES, regs.u.r16.di, 0xfeffc000L, >> > > +                    0xff000000L, 0, 0, 2); >> > >              regs.u.r32.ebx = 6; >> > >              break; >> > >            case 6: >> > > -             /* 256KB BIOS area at the end of 4 GB */ >> > > +             /* 16MB BIOS area at the end of 4 GB */ >> > >              set_e820_range(ES, regs.u.r16.di, >> > > -                    0xfffc0000L, 0x00000000L ,0, 0, >> > > 2); +                    0xff000000L, 0x00000000L >> > > ,0, 0, 2); if (extra_highbits_memory_size || >> > > extra_lowbits_memory_size) regs.u.r32.ebx = 7; >> > >              else >> > > diff --git a/kvm/include/x86/asm/vmx.h b/kvm/include/x86/asm/vmx.h >> > > index df8d4f9..99e2bb9 100644 >> > > --- a/kvm/include/x86/asm/vmx.h >> > > +++ b/kvm/include/x86/asm/vmx.h >> > > @@ -403,7 +403,7 @@ enum vmcs_field { >> > >  #define VMX_EPT_EXECUTABLE_MASK            0x4ull >> > >  #define VMX_EPT_IGMT_BIT           (1ull << 6) >> > > >> > > -#define VMX_EPT_IDENTITY_PAGETABLE_ADDR        0xfffbc000ul >> > > +#define VMX_EPT_IDENTITY_PAGETABLE_ADDR        0xfeffc000ul >> > > >> > > >> > >  #define ASM_VMX_VMCLEAR_RAX    ".byte 0x66, 0x0f, 0xc7, 0x30" >> > > diff --git a/qemu-kvm-x86.c b/qemu-kvm-x86.c >> > > index daf60b6..b5306aa 100644 >> > > --- a/qemu-kvm-x86.c >> > > +++ b/qemu-kvm-x86.c >> > > @@ -63,7 +63,7 @@ static int kvm_init_tss(kvm_context_t kvm) >> > >         * this address is 3 pages before the bios, and the bios >> > > should present * as unavaible memory >> > >         */ >> > > -       r = kvm_set_tss_addr(kvm, 0xfffbd000); >> > > +       r = kvm_set_tss_addr(kvm, 0xfeffd000); >> > >        if (r < 0) { >> > >            fprintf(stderr, "kvm_init_tss: unable to set tss >> > > addr\n"); return r; >> > >> > -- >> > To unsubscribe from this list: send the line "unsubscribe kvm" in >> > the body of a message to majordomo@vger.kernel.org >> > More majordomo info at  http://vger.kernel.org/majordomo-info.html >> >> -- >> To unsubscribe from this list: send the line "unsubscribe kvm" in >> the body of a message to majordomo@vger.kernel.org >> More majordomo info at  http://vger.kernel.org/majordomo-info.html > > > -- To unsubscribe from this list: send the line "unsubscribe kvm" in the body of a message to majordomo@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html
On Thursday 16 July 2009 12:57:02 Jordan Justen wrote: > On Wed, Jul 15, 2009 at 8:08 PM, Sheng Yang<sheng@linux.intel.com> wrote: > > On Thursday 16 July 2009 10:58:53 Jordan Justen wrote: > >> On Wed, Jul 15, 2009 at 6:34 PM, Sheng Yang <sheng@linux.intel.com> wrote: > >> > On Thursday 16 July 2009 08:12:15 Jordan Justen wrote: > >> > > Motivation for making these changes: > >> > > > >> > > A larger firmware image size allows alternative BIOS images to be > >> > > used with KVM. Some possible uses are to enable UEFI firmware > >> > > or coreboot firmware. Additionally, an alternative firmware might > >> > > include a linux kernel+initrd payload, which would require several > >> > > megabytes. > >> > > >> > I think if you update bios to UEFI, the E820 should be represented by > >> > UEFI rather than current bios? > >> > >> Yeah, that is true. But, that firmware would be separate from the > >> qemu-kvm tree at this time, right? > > > > Yes, so currently from QEmu-kvm side, I think it may not necessary to > > update, for the patches haven't followed up yet... > > Of the two patches (1. kvm kernel module, 2. qemu-kvm), I think it > is best if the qemu-kvm change happens first. Since the qemu-kvm > patch will cause the qemu-kvm bios to add more memory regions > as reserved, the new change to qemu-kvm will be compatible with > both the old and new versions of the kvm kernel module. > > >> But, in this patch it is critical that the 'VMX TSS Pages' are moved > >> within qemu-kvm so the conflict with the larger bios.bin is removed. > > > > Well, for we are using a small size bios now, and larger bios would be > > totally another story, I don't think push the modification now to the > > upstream make sense. These modification can go with further patches with > > UEFI at any time in the future. > > I am working on this UEFI firmware project which currently supports QEMU: > https://edk2.tianocore.org/OVMF.html > > I would like it to also support KVM, and I found that it can already boot > the UEFI shell on KVM if these two patches are applied. > > If these patches make some progress, I will update OVMF to reserve the > appropriate memory regions. Make sense to me. So what's mattered here is not bios, but qemu-kvm and kvm code. The user can replace bios binary by UEFI binary easily, but not with kvm related part. I realized you still need separate the qemu-kvm patch into two: one for bios and another for qemu. And I just hope this modification won't break some old OS(any OS got assumption about bios size? I think Tiano team should have idea on it)...
On Wed, Jul 15, 2009 at 10:37 PM, Sheng Yang<sheng@linux.intel.com> wrote: > Make sense to me. So what's mattered here is not bios, but qemu-kvm and kvm > code. The user can replace bios binary by UEFI binary easily, but not with kvm > related part. > > I realized you still need separate the qemu-kvm patch into two: one for bios > and another for qemu. Okay, I will split this change apart. > And I just hope this modification won't break some old > OS(any OS got assumption about bios size? I think Tiano team should have idea > on it)... I don't think the OS should care about the bios size, but it is important to update the INT15-E820 memory ranges to help make sure the OS knows which regions are in use. Even without the E820 change, I think it would be unlikely for an OS to try utilize these memory regions, but it is definitely better to properly describe it. -- To unsubscribe from this list: send the line "unsubscribe kvm" in the body of a message to majordomo@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html
On Thu, 2009-07-16 at 10:57 -0700, Jordan Justen wrote: > On Wed, Jul 15, 2009 at 10:37 PM, Sheng Yang<sheng@linux.intel.com> wrote: > > Make sense to me. So what's mattered here is not bios, but qemu-kvm and kvm > > code. The user can replace bios binary by UEFI binary easily, but not with kvm > > related part. > > > > I realized you still need separate the qemu-kvm patch into two: one for bios > > and another for qemu. > > Okay, I will split this change apart. > > > And I just hope this modification won't break some old > > OS(any OS got assumption about bios size? I think Tiano team should have idea > > on it)... > > I don't think the OS should care about the bios size, but it is > important to update the INT15-E820 memory ranges to help > make sure the OS knows which regions are in use. > > Even without the E820 change, I think it would be unlikely > for an OS to try utilize these memory regions, but it is > definitely better to properly describe it. Hello, I don't know if I get this right, but is it enough to apply this patch to KVM-userspace, or do I also need to have a patched kernel in order to get large images (my image is 4MB) to work in KVM? Thanks, Cristi
On Thursday 23 July 2009 03:04:33 Cristi Magherusan wrote: > On Thu, 2009-07-16 at 10:57 -0700, Jordan Justen wrote: > > On Wed, Jul 15, 2009 at 10:37 PM, Sheng Yang<sheng@linux.intel.com> wrote: > > > Make sense to me. So what's mattered here is not bios, but qemu-kvm and > > > kvm code. The user can replace bios binary by UEFI binary easily, but > > > not with kvm related part. > > > > > > I realized you still need separate the qemu-kvm patch into two: one for > > > bios and another for qemu. > > > > Okay, I will split this change apart. > > > > > And I just hope this modification won't break some old > > > OS(any OS got assumption about bios size? I think Tiano team should > > > have idea on it)... > > > > I don't think the OS should care about the bios size, but it is > > important to update the INT15-E820 memory ranges to help > > make sure the OS knows which regions are in use. > > > > Even without the E820 change, I think it would be unlikely > > for an OS to try utilize these memory regions, but it is > > definitely better to properly describe it. > > Hello, > > I don't know if I get this right, but is it enough to apply this patch > to KVM-userspace, or do I also need to have a patched kernel in order to > get large images (my image is 4MB) to work in KVM? > You need a patched KVM kernel modules for this. And you can use Jordan's patch currently(http://article.gmane.org/gmane.comp.emulators.kvm.devel/37344). The first one for BIOS(apply to qemu-kvm tree), second of qemu-kvm, and the third for KVM modules.
diff --git a/kvm/bios/rombios.c b/kvm/bios/rombios.c index 6186199..2d0c153 100644 --- a/kvm/bios/rombios.c +++ b/kvm/bios/rombios.c @@ -4596,14 +4596,14 @@ ASM_END case 5: /* 4 pages before the bios, 3 pages for vmx tss pages, * the other page for EPT real mode pagetable */ - set_e820_range(ES, regs.u.r16.di, 0xfffbc000L, - 0xfffc0000L, 0, 0, 2); + set_e820_range(ES, regs.u.r16.di, 0xfeffc000L, + 0xff000000L, 0, 0, 2); regs.u.r32.ebx = 6; break; case 6: - /* 256KB BIOS area at the end of 4 GB */ + /* 16MB BIOS area at the end of 4 GB */ set_e820_range(ES, regs.u.r16.di, - 0xfffc0000L, 0x00000000L ,0, 0, 2); + 0xff000000L, 0x00000000L ,0, 0, 2); if (extra_highbits_memory_size || extra_lowbits_memory_size) regs.u.r32.ebx = 7; else diff --git a/kvm/include/x86/asm/vmx.h b/kvm/include/x86/asm/vmx.h index df8d4f9..99e2bb9 100644 --- a/kvm/include/x86/asm/vmx.h +++ b/kvm/include/x86/asm/vmx.h @@ -403,7 +403,7 @@ enum vmcs_field { #define VMX_EPT_EXECUTABLE_MASK 0x4ull #define VMX_EPT_IGMT_BIT (1ull << 6) -#define VMX_EPT_IDENTITY_PAGETABLE_ADDR 0xfffbc000ul +#define VMX_EPT_IDENTITY_PAGETABLE_ADDR 0xfeffc000ul #define ASM_VMX_VMCLEAR_RAX ".byte 0x66, 0x0f, 0xc7, 0x30" diff --git a/qemu-kvm-x86.c b/qemu-kvm-x86.c index daf60b6..b5306aa 100644 --- a/qemu-kvm-x86.c +++ b/qemu-kvm-x86.c @@ -63,7 +63,7 @@ static int kvm_init_tss(kvm_context_t kvm) * this address is 3 pages before the bios, and the bios should present * as unavaible memory */ - r = kvm_set_tss_addr(kvm, 0xfffbd000); + r = kvm_set_tss_addr(kvm, 0xfeffd000); if (r < 0) { fprintf(stderr, "kvm_init_tss: unable to set tss addr\n"); return r;
Previously the KVM kernel module would allocate the address range of 0xfffbc000-0xfffbcfff for the EPT Indentity Page Tables. A separate patch is moving that to 0xfeffc000-0xfeffcfff. This patch updates qemu-kvm to move the VMX TSS Pages & update the KVM BIOS code to update the E820 BIOS call memory reservations. Previously, the VMC TSS Pages were located at 0xfffbd000-0xfffbffff. This change moved them to 0xfeffd000-0xfeffffff. This change also updates the KVM bios such that the E820 locations are returned properly for these two changes. From a high level, these are the effects of these two changes: Previously, the KVM would only accommodate a 256KB BIOS image. With these changes, the BIOS image may now grow to 16MB. Motivation for making these changes: A larger firmware image size allows alternative BIOS images to be used with KVM. Some possible uses are to enable UEFI firmware or coreboot firmware. Additionally, an alternative firmware might include a linux kernel+initrd payload, which would require several megabytes. Signed-off-by: Jordan Justen <jordan.l.justen@intel.com> --- kvm/bios/rombios.c | 8 ++++---- kvm/include/x86/asm/vmx.h | 2 +- qemu-kvm-x86.c | 2 +- 3 files changed, 6 insertions(+), 6 deletions(-)