| Message ID | 1420627503-25183-1-git-send-email-marc.zyngier@arm.com (mailing list archive) |
|---|---|
| State | New, archived |
| Headers | show |
Hi Marc, On 07/01/15 10:45, Marc Zyngier wrote: > 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> > --- > 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..36dcef6 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)) ^ whitespace is here Vladimir > + 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; > } > -- IMPORTANT NOTICE: The contents of this email and any attachments are confidential and may also be privileged. If you are not the intended recipient, please notify the sender immediately and do not disclose the contents to any other person, use it for any purpose, or store or copy the information in any medium. Thank you. ARM Limited, Registered office 110 Fulbourn Road, Cambridge CB1 9NJ, Registered in England & Wales, Company No: 2557590 ARM Holdings plc, Registered office 110 Fulbourn Road, Cambridge CB1 9NJ, Registered in England & Wales, Company No: 2548782 -- 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 Wed, Jan 07, 2015 at 10:45:03AM +0000, Marc Zyngier wrote: > 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> Whoops, thanks for the fix. Acked-by: Christoffer Dall <christoffer.dall@linaro.org> -- 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
diff --git a/arch/arm64/include/asm/kvm_emulate.h b/arch/arm64/include/asm/kvm_emulate.h index 8127e45..36dcef6 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; }
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> --- arch/arm64/include/asm/kvm_emulate.h | 2 ++ arch/arm64/kvm/reset.c | 1 - 2 files changed, 2 insertions(+), 1 deletion(-)