[PATCH] Update KVM kernel module to allow a larger BIOS image.

[PATCH] Update KVM kernel module to allow a larger BIOS image.

[Jordan Justen]

Previously the KVM kernel module would allocate the address range
of 0xfffbc000-0xfffbcfff for the EPT Indentity Page Tables.
This change moves that to 0xfeffc000-0xfeffcfff.

Another issue related to this change is the VMC TSS Pages were
located at 0xfffbd000-0xfffbffff.  This is controlled by the
qemu-kvm code.  A separate change will move them to
0xfeffd000-0xfeffffff.

>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>
---
 arch/x86/include/asm/vmx.h |    2 +-
 1 files changed, 1 insertions(+), 1 deletions(-)

diff --git a/arch/x86/include/asm/vmx.h b/arch/x86/include/asm/vmx.h
index 272514c..0086332 100644
--- a/arch/x86/include/asm/vmx.h
+++ b/arch/x86/include/asm/vmx.h
@@ -372,7 +372,7 @@ 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"
-- 
1.6.0.4

[PATCH] Update qemu-kvm to allow a larger BIOS image.

[Jordan Justen]

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(-)

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;
-- 
1.6.0.4

Re: [PATCH] Update qemu-kvm to allow a larger BIOS image.

[Sheng Yang]

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?

-- 
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;

Re: [PATCH] Update qemu-kvm to allow a larger BIOS image.

[Jordan Justen]

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

Re: [PATCH] Update qemu-kvm to allow a larger BIOS image.

[Sheng Yang]

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.

-- 
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

Re: [PATCH] Update qemu-kvm to allow a larger BIOS image.

[Jordan Justen]

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
>
>
>

Re: [PATCH] Update qemu-kvm to allow a larger BIOS image.

[Sheng Yang]

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)...

-- 
regards
Yang, Sheng

>
> > --
> > 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

Re: [PATCH] Update qemu-kvm to allow a larger BIOS image.

[Jordan Justen]

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.

Re: [PATCH] Update qemu-kvm to allow a larger BIOS image.

[Cristi Magherusan]

[-- Attachment #1: Type: text/plain, Size: 1363 bytes --]

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

-- 
Ing. Cristi Măgherușan, System/Network Engineer
Technical University of Cluj-Napoca, Romania
http://cc.utcluj.ro  +40264 401247

[-- Attachment #2: This is a digitally signed message part --]
[-- Type: application/pgp-signature, Size: 197 bytes --]

Re: [PATCH] Update qemu-kvm to allow a larger BIOS image.

[Sheng Yang]

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.

-- 
regards
Yang, Sheng