[GIT PULL 0/2] KVM/ARM Fixes for 3.19

[GIT PULL 0/2] KVM/ARM Fixes for 3.19

[Christoffer Dall]

Hi Paolo,

The following changes since commit b1940cd21c0f4abdce101253e860feff547291b0:

  Linux 3.19-rc3 (2015-01-05 17:05:20 -0800)

are available in the git repository at:

  git://git.kernel.org/pub/scm/linux/kernel/git/kvmarm/kvmarm.git tags/kvm-arm-fixes-3.19

for you to fetch changes up to b5b8ddba844c6b6c5b96c27b284d9ed05a16fa13:

  arm64: KVM: Fix HCR setting for 32bit guests (2015-01-11 13:54:51 +0100)

(Note that I got an extra merge commit when merging kvm/master into
kvmarm/master, which I think is because Linus applied the set of fixes
from kvmarm/master directly from Marc's patches. Let me know if you need
me to mangle this differently somehow.)

Thanks,
-Christoffer

----------------------------------------------------------------
Fixes for KVM/ARM for 3.19 addressing TLB invalidation issues and 32-bit guest
regression.

----------------------------------------------------------------
Marc Zyngier (2):
      arm64: KVM: Fix TLB invalidation by IPA/VMID
      arm64: KVM: Fix HCR setting for 32bit guests

 arch/arm64/include/asm/kvm_emulate.h | 2 ++
 arch/arm64/kvm/hyp.S                 | 1 +
 arch/arm64/kvm/reset.c               | 1 -
 3 files changed, 3 insertions(+), 1 deletion(-)

[GIT PULL 0/2] KVM/ARM Fixes for 3.19

[Christoffer Dall]

Hi Paolo,

The following changes since commit b1940cd21c0f4abdce101253e860feff547291b0:

  Linux 3.19-rc3 (2015-01-05 17:05:20 -0800)

are available in the git repository at:

  git://git.kernel.org/pub/scm/linux/kernel/git/kvmarm/kvmarm.git tags/kvm-arm-fixes-3.19

for you to fetch changes up to b5b8ddba844c6b6c5b96c27b284d9ed05a16fa13:

  arm64: KVM: Fix HCR setting for 32bit guests (2015-01-11 13:54:51 +0100)

(Note that I got an extra merge commit when merging kvm/master into
kvmarm/master, which I think is because Linus applied the set of fixes
from kvmarm/master directly from Marc's patches. Let me know if you need
me to mangle this differently somehow.)

Thanks,
-Christoffer

----------------------------------------------------------------
Fixes for KVM/ARM for 3.19 addressing TLB invalidation issues and 32-bit guest
regression.

----------------------------------------------------------------
Marc Zyngier (2):
      arm64: KVM: Fix TLB invalidation by IPA/VMID
      arm64: KVM: Fix HCR setting for 32bit guests

 arch/arm64/include/asm/kvm_emulate.h | 2 ++
 arch/arm64/kvm/hyp.S                 | 1 +
 arch/arm64/kvm/reset.c               | 1 -
 3 files changed, 3 insertions(+), 1 deletion(-)

[GIT PULL 1/2] arm64: KVM: Fix TLB invalidation by IPA/VMID

[Christoffer Dall]

From: Marc Zyngier <marc.zyngier@arm.com>

It took about two years for someone to notice that the IPA passed
to TLBI IPAS2E1IS must be shifted by 12 bits. Clearly our reviewing
is not as good as it should be...

Paper bag time for me.

Reported-by: Mario Smarduch <m.smarduch@samsung.com>
Tested-by: Mario Smarduch <m.smarduch@samsung.com>
Signed-off-by: Marc Zyngier <marc.zyngier@arm.com>
Signed-off-by: Christoffer Dall <christoffer.dall@linaro.org>
---
 arch/arm64/kvm/hyp.S | 1 +
 1 file changed, 1 insertion(+)

diff --git a/arch/arm64/kvm/hyp.S b/arch/arm64/kvm/hyp.S
index fbe909f..c3ca89c 100644
--- a/arch/arm64/kvm/hyp.S
+++ b/arch/arm64/kvm/hyp.S
@@ -1014,6 +1014,7 @@ ENTRY(__kvm_tlb_flush_vmid_ipa)
 	 * Instead, we invalidate Stage-2 for this IPA, and the
 	 * whole of Stage-1. Weep...
 	 */
+	lsr	x1, x1, #12
 	tlbi	ipas2e1is, x1
 	/*
 	 * We have to ensure completion of the invalidation at Stage-2,
-- 
2.1.2.330.g565301e.dirty

[GIT PULL 1/2] arm64: KVM: Fix TLB invalidation by IPA/VMID

[Christoffer Dall]

From: Marc Zyngier <marc.zyngier@arm.com>

It took about two years for someone to notice that the IPA passed
to TLBI IPAS2E1IS must be shifted by 12 bits. Clearly our reviewing
is not as good as it should be...

Paper bag time for me.

Reported-by: Mario Smarduch <m.smarduch@samsung.com>
Tested-by: Mario Smarduch <m.smarduch@samsung.com>
Signed-off-by: Marc Zyngier <marc.zyngier@arm.com>
Signed-off-by: Christoffer Dall <christoffer.dall@linaro.org>
---
 arch/arm64/kvm/hyp.S | 1 +
 1 file changed, 1 insertion(+)

diff --git a/arch/arm64/kvm/hyp.S b/arch/arm64/kvm/hyp.S
index fbe909f..c3ca89c 100644
--- a/arch/arm64/kvm/hyp.S
+++ b/arch/arm64/kvm/hyp.S
@@ -1014,6 +1014,7 @@ ENTRY(__kvm_tlb_flush_vmid_ipa)
 	 * Instead, we invalidate Stage-2 for this IPA, and the
 	 * whole of Stage-1. Weep...
 	 */
+	lsr	x1, x1, #12
 	tlbi	ipas2e1is, x1
 	/*
 	 * We have to ensure completion of the invalidation at Stage-2,
-- 
2.1.2.330.g565301e.dirty

[GIT PULL 2/2] arm64: KVM: Fix HCR setting for 32bit guests

[Christoffer Dall]

From: Marc Zyngier <marc.zyngier@arm.com>

Commit b856a59141b1 (arm/arm64: KVM: Reset the HCR on each vcpu
when resetting the vcpu) moved the init of the HCR register to
happen later in the init of a vcpu, but left out the fixup
done in kvm_reset_vcpu when preparing for a 32bit guest.

As a result, the 32bit guest is run as a 64bit guest, but the
rest of the kernel still manages it as a 32bit. Fun follows.

Moving the fixup to vcpu_reset_hcr solves the problem for good.

Signed-off-by: Marc Zyngier <marc.zyngier@arm.com>
Signed-off-by: Christoffer Dall <christoffer.dall@linaro.org>
---
 arch/arm64/include/asm/kvm_emulate.h | 2 ++
 arch/arm64/kvm/reset.c               | 1 -
 2 files changed, 2 insertions(+), 1 deletion(-)

diff --git a/arch/arm64/include/asm/kvm_emulate.h b/arch/arm64/include/asm/kvm_emulate.h
index 8127e45..865a7e2 100644
--- a/arch/arm64/include/asm/kvm_emulate.h
+++ b/arch/arm64/include/asm/kvm_emulate.h
@@ -41,6 +41,8 @@ void kvm_inject_pabt(struct kvm_vcpu *vcpu, unsigned long addr);
 static inline void vcpu_reset_hcr(struct kvm_vcpu *vcpu)
 {
 	vcpu->arch.hcr_el2 = HCR_GUEST_FLAGS;
+	if (test_bit(KVM_ARM_VCPU_EL1_32BIT, vcpu->arch.features))
+		vcpu->arch.hcr_el2 &= ~HCR_RW;
 }
 
 static inline unsigned long *vcpu_pc(const struct kvm_vcpu *vcpu)
diff --git a/arch/arm64/kvm/reset.c b/arch/arm64/kvm/reset.c
index 70a7816..0b43265 100644
--- a/arch/arm64/kvm/reset.c
+++ b/arch/arm64/kvm/reset.c
@@ -90,7 +90,6 @@ int kvm_reset_vcpu(struct kvm_vcpu *vcpu)
 			if (!cpu_has_32bit_el1())
 				return -EINVAL;
 			cpu_reset = &default_regs_reset32;
-			vcpu->arch.hcr_el2 &= ~HCR_RW;
 		} else {
 			cpu_reset = &default_regs_reset;
 		}
-- 
2.1.2.330.g565301e.dirty

[GIT PULL 2/2] arm64: KVM: Fix HCR setting for 32bit guests

[Christoffer Dall]

From: Marc Zyngier <marc.zyngier@arm.com>

Commit b856a59141b1 (arm/arm64: KVM: Reset the HCR on each vcpu
when resetting the vcpu) moved the init of the HCR register to
happen later in the init of a vcpu, but left out the fixup
done in kvm_reset_vcpu when preparing for a 32bit guest.

As a result, the 32bit guest is run as a 64bit guest, but the
rest of the kernel still manages it as a 32bit. Fun follows.

Moving the fixup to vcpu_reset_hcr solves the problem for good.

Signed-off-by: Marc Zyngier <marc.zyngier@arm.com>
Signed-off-by: Christoffer Dall <christoffer.dall@linaro.org>
---
 arch/arm64/include/asm/kvm_emulate.h | 2 ++
 arch/arm64/kvm/reset.c               | 1 -
 2 files changed, 2 insertions(+), 1 deletion(-)

diff --git a/arch/arm64/include/asm/kvm_emulate.h b/arch/arm64/include/asm/kvm_emulate.h
index 8127e45..865a7e2 100644
--- a/arch/arm64/include/asm/kvm_emulate.h
+++ b/arch/arm64/include/asm/kvm_emulate.h
@@ -41,6 +41,8 @@ void kvm_inject_pabt(struct kvm_vcpu *vcpu, unsigned long addr);
 static inline void vcpu_reset_hcr(struct kvm_vcpu *vcpu)
 {
 	vcpu->arch.hcr_el2 = HCR_GUEST_FLAGS;
+	if (test_bit(KVM_ARM_VCPU_EL1_32BIT, vcpu->arch.features))
+		vcpu->arch.hcr_el2 &= ~HCR_RW;
 }
 
 static inline unsigned long *vcpu_pc(const struct kvm_vcpu *vcpu)
diff --git a/arch/arm64/kvm/reset.c b/arch/arm64/kvm/reset.c
index 70a7816..0b43265 100644
--- a/arch/arm64/kvm/reset.c
+++ b/arch/arm64/kvm/reset.c
@@ -90,7 +90,6 @@ int kvm_reset_vcpu(struct kvm_vcpu *vcpu)
 			if (!cpu_has_32bit_el1())
 				return -EINVAL;
 			cpu_reset = &default_regs_reset32;
-			vcpu->arch.hcr_el2 &= ~HCR_RW;
 		} else {
 			cpu_reset = &default_regs_reset;
 		}
-- 
2.1.2.330.g565301e.dirty

Re: [GIT PULL 0/2] KVM/ARM Fixes for 3.19

[Paolo Bonzini]

On 11/01/2015 14:10, Christoffer Dall wrote:
> Hi Paolo,
> 
> The following changes since commit b1940cd21c0f4abdce101253e860feff547291b0:
> 
>   Linux 3.19-rc3 (2015-01-05 17:05:20 -0800)
> 
> are available in the git repository at:
> 
>   git://git.kernel.org/pub/scm/linux/kernel/git/kvmarm/kvmarm.git tags/kvm-arm-fixes-3.19
> 
> for you to fetch changes up to b5b8ddba844c6b6c5b96c27b284d9ed05a16fa13:
> 
>   arm64: KVM: Fix HCR setting for 32bit guests (2015-01-11 13:54:51 +0100)
> 
> (Note that I got an extra merge commit when merging kvm/master into
> kvmarm/master, which I think is because Linus applied the set of fixes
> from kvmarm/master directly from Marc's patches. Let me know if you need
> me to mangle this differently somehow.)

Hmm, that's a bit ugly.  I'll apply the patches directly too, please do
a "git reset --hard kvm/master" before applying more stuff.

Paolo

[GIT PULL 0/2] KVM/ARM Fixes for 3.19

[Paolo Bonzini]

On 11/01/2015 14:10, Christoffer Dall wrote:
> Hi Paolo,
> 
> The following changes since commit b1940cd21c0f4abdce101253e860feff547291b0:
> 
>   Linux 3.19-rc3 (2015-01-05 17:05:20 -0800)
> 
> are available in the git repository at:
> 
>   git://git.kernel.org/pub/scm/linux/kernel/git/kvmarm/kvmarm.git tags/kvm-arm-fixes-3.19
> 
> for you to fetch changes up to b5b8ddba844c6b6c5b96c27b284d9ed05a16fa13:
> 
>   arm64: KVM: Fix HCR setting for 32bit guests (2015-01-11 13:54:51 +0100)
> 
> (Note that I got an extra merge commit when merging kvm/master into
> kvmarm/master, which I think is because Linus applied the set of fixes
> from kvmarm/master directly from Marc's patches. Let me know if you need
> me to mangle this differently somehow.)

Hmm, that's a bit ugly.  I'll apply the patches directly too, please do
a "git reset --hard kvm/master" before applying more stuff.

Paolo

Re: [GIT PULL 0/2] KVM/ARM Fixes for 3.19

[Christoffer Dall]

On Mon, Jan 12, 2015 at 11:15:00AM +0100, Paolo Bonzini wrote:
> 
> 
> On 11/01/2015 14:10, Christoffer Dall wrote:
> > Hi Paolo,
> > 
> > The following changes since commit b1940cd21c0f4abdce101253e860feff547291b0:
> > 
> >   Linux 3.19-rc3 (2015-01-05 17:05:20 -0800)
> > 
> > are available in the git repository at:
> > 
> >   git://git.kernel.org/pub/scm/linux/kernel/git/kvmarm/kvmarm.git tags/kvm-arm-fixes-3.19
> > 
> > for you to fetch changes up to b5b8ddba844c6b6c5b96c27b284d9ed05a16fa13:
> > 
> >   arm64: KVM: Fix HCR setting for 32bit guests (2015-01-11 13:54:51 +0100)
> > 
> > (Note that I got an extra merge commit when merging kvm/master into
> > kvmarm/master, which I think is because Linus applied the set of fixes
> > from kvmarm/master directly from Marc's patches. Let me know if you need
> > me to mangle this differently somehow.)
> 
> Hmm, that's a bit ugly.  I'll apply the patches directly too, please do
> a "git reset --hard kvm/master" before applying more stuff.
> 
ok, we did try to (and say publicly) that we'd keep kvmarm/master a
stable branch (like it also says about kvm/master on the KVM wiki), so
that's why I did this.

I guess we can just require people that follow kvmarm/master (if any) to
deal with things accordingly.

-Christoffer

[GIT PULL 0/2] KVM/ARM Fixes for 3.19

[Christoffer Dall]

On Mon, Jan 12, 2015 at 11:15:00AM +0100, Paolo Bonzini wrote:
> 
> 
> On 11/01/2015 14:10, Christoffer Dall wrote:
> > Hi Paolo,
> > 
> > The following changes since commit b1940cd21c0f4abdce101253e860feff547291b0:
> > 
> >   Linux 3.19-rc3 (2015-01-05 17:05:20 -0800)
> > 
> > are available in the git repository at:
> > 
> >   git://git.kernel.org/pub/scm/linux/kernel/git/kvmarm/kvmarm.git tags/kvm-arm-fixes-3.19
> > 
> > for you to fetch changes up to b5b8ddba844c6b6c5b96c27b284d9ed05a16fa13:
> > 
> >   arm64: KVM: Fix HCR setting for 32bit guests (2015-01-11 13:54:51 +0100)
> > 
> > (Note that I got an extra merge commit when merging kvm/master into
> > kvmarm/master, which I think is because Linus applied the set of fixes
> > from kvmarm/master directly from Marc's patches. Let me know if you need
> > me to mangle this differently somehow.)
> 
> Hmm, that's a bit ugly.  I'll apply the patches directly too, please do
> a "git reset --hard kvm/master" before applying more stuff.
> 
ok, we did try to (and say publicly) that we'd keep kvmarm/master a
stable branch (like it also says about kvm/master on the KVM wiki), so
that's why I did this.

I guess we can just require people that follow kvmarm/master (if any) to
deal with things accordingly.

-Christoffer

Re: [GIT PULL 0/2] KVM/ARM Fixes for 3.19

[Paolo Bonzini]

On 12/01/2015 18:19, Christoffer Dall wrote:
>> > Hmm, that's a bit ugly.  I'll apply the patches directly too, please do
>> > a "git reset --hard kvm/master" before applying more stuff.
>> > 
> ok, we did try to (and say publicly) that we'd keep kvmarm/master a
> stable branch (like it also says about kvm/master on the KVM wiki), so
> that's why I did this.
> 
> I guess we can just require people that follow kvmarm/master (if any) to
> deal with things accordingly.

Yeah, I agree that this shouldn't have happened.

It's not the end of the world.  People that pull from kvmarm/master will
almost always rebase their trees, and the rebase will discard the
duplicate patches.

The big problem with rebasing happens if you _drop_ patches.  In that
case, whoever rebases will keep the patch that you dropped, and most
likely will not notice.

Paolo

[GIT PULL 0/2] KVM/ARM Fixes for 3.19

[Paolo Bonzini]

On 12/01/2015 18:19, Christoffer Dall wrote:
>> > Hmm, that's a bit ugly.  I'll apply the patches directly too, please do
>> > a "git reset --hard kvm/master" before applying more stuff.
>> > 
> ok, we did try to (and say publicly) that we'd keep kvmarm/master a
> stable branch (like it also says about kvm/master on the KVM wiki), so
> that's why I did this.
> 
> I guess we can just require people that follow kvmarm/master (if any) to
> deal with things accordingly.

Yeah, I agree that this shouldn't have happened.

It's not the end of the world.  People that pull from kvmarm/master will
almost always rebase their trees, and the rebase will discard the
duplicate patches.

The big problem with rebasing happens if you _drop_ patches.  In that
case, whoever rebases will keep the patch that you dropped, and most
likely will not notice.

Paolo

Re: [GIT PULL 0/2] KVM/ARM Fixes for 3.19

[Christoffer Dall]

On Mon, Jan 12, 2015 at 07:36:14PM +0100, Paolo Bonzini wrote:
> 
> 
> On 12/01/2015 18:19, Christoffer Dall wrote:
> >> > Hmm, that's a bit ugly.  I'll apply the patches directly too, please do
> >> > a "git reset --hard kvm/master" before applying more stuff.
> >> > 
> > ok, we did try to (and say publicly) that we'd keep kvmarm/master a
> > stable branch (like it also says about kvm/master on the KVM wiki), so
> > that's why I did this.
> > 
> > I guess we can just require people that follow kvmarm/master (if any) to
> > deal with things accordingly.
> 
> Yeah, I agree that this shouldn't have happened.
> 
> It's not the end of the world.  People that pull from kvmarm/master will
> almost always rebase their trees, and the rebase will discard the
> duplicate patches.
> 
> The big problem with rebasing happens if you _drop_ patches.  In that
> case, whoever rebases will keep the patch that you dropped, and most
> likely will not notice.
> 
That's a good point.  And I don't think anyone directly integrates the
kvmarm/master branch into anything anyway.

I will reset the branch.


Thanks,
-Christoffer

[GIT PULL 0/2] KVM/ARM Fixes for 3.19

[Christoffer Dall]

On Mon, Jan 12, 2015 at 07:36:14PM +0100, Paolo Bonzini wrote:
> 
> 
> On 12/01/2015 18:19, Christoffer Dall wrote:
> >> > Hmm, that's a bit ugly.  I'll apply the patches directly too, please do
> >> > a "git reset --hard kvm/master" before applying more stuff.
> >> > 
> > ok, we did try to (and say publicly) that we'd keep kvmarm/master a
> > stable branch (like it also says about kvm/master on the KVM wiki), so
> > that's why I did this.
> > 
> > I guess we can just require people that follow kvmarm/master (if any) to
> > deal with things accordingly.
> 
> Yeah, I agree that this shouldn't have happened.
> 
> It's not the end of the world.  People that pull from kvmarm/master will
> almost always rebase their trees, and the rebase will discard the
> duplicate patches.
> 
> The big problem with rebasing happens if you _drop_ patches.  In that
> case, whoever rebases will keep the patch that you dropped, and most
> likely will not notice.
> 
That's a good point.  And I don't think anyone directly integrates the
kvmarm/master branch into anything anyway.

I will reset the branch.


Thanks,
-Christoffer