| Message ID | 1368529900-22572-6-git-send-email-marc.zyngier@arm.com (mailing list archive) |
|---|---|
| State | New, archived |
| Headers | show |
On Tue, May 14, 2013 at 12:11:38PM +0100, Marc Zyngier wrote: > Admitedly, reading a MMIO register to load PC is very weird. > Writing PC to a MMIO register is probably even worse. But > the architecture doesn't forbid any of these, and injecting > a Prefetch Abort is the wrong thing to do anyway. > > Remove this check altogether, and let the adventurous guest > wander into LaLaLand if they feel compelled to do so. > > Reported-by: Catalin Marinas <catalin.marinas@arm.com> > Signed-off-by: Marc Zyngier <marc.zyngier@arm.com> > --- > arch/arm/include/asm/kvm_emulate.h | 5 ----- > arch/arm/kvm/mmio.c | 6 ------ > 2 files changed, 11 deletions(-) > > diff --git a/arch/arm/include/asm/kvm_emulate.h b/arch/arm/include/asm/kvm_emulate.h > index 82b4bab..a464e8d 100644 > --- a/arch/arm/include/asm/kvm_emulate.h > +++ b/arch/arm/include/asm/kvm_emulate.h > @@ -65,11 +65,6 @@ static inline bool vcpu_mode_priv(struct kvm_vcpu *vcpu) > return cpsr_mode > USR_MODE;; > } > > -static inline bool kvm_vcpu_reg_is_pc(struct kvm_vcpu *vcpu, int reg) > -{ > - return reg == 15; > -} > - > static inline u32 kvm_vcpu_get_hsr(struct kvm_vcpu *vcpu) > { > return vcpu->arch.fault.hsr; > diff --git a/arch/arm/kvm/mmio.c b/arch/arm/kvm/mmio.c > index 72a12f2..b8e06b7 100644 > --- a/arch/arm/kvm/mmio.c > +++ b/arch/arm/kvm/mmio.c > @@ -86,12 +86,6 @@ static int decode_hsr(struct kvm_vcpu *vcpu, phys_addr_t fault_ipa, > sign_extend = kvm_vcpu_dabt_issext(vcpu); > rt = kvm_vcpu_dabt_get_rd(vcpu); > > - if (kvm_vcpu_reg_is_pc(vcpu, rt)) { > - /* IO memory trying to read/write pc */ > - kvm_inject_pabt(vcpu, kvm_vcpu_get_hfar(vcpu)); > - return 1; > - } > - > mmio->is_write = is_write; > mmio->phys_addr = fault_ipa; > mmio->len = len; > -- > 1.8.2.3 > > Applied, thanks. -Christoffer
diff --git a/arch/arm/include/asm/kvm_emulate.h b/arch/arm/include/asm/kvm_emulate.h index 82b4bab..a464e8d 100644 --- a/arch/arm/include/asm/kvm_emulate.h +++ b/arch/arm/include/asm/kvm_emulate.h @@ -65,11 +65,6 @@ static inline bool vcpu_mode_priv(struct kvm_vcpu *vcpu) return cpsr_mode > USR_MODE;; } -static inline bool kvm_vcpu_reg_is_pc(struct kvm_vcpu *vcpu, int reg) -{ - return reg == 15; -} - static inline u32 kvm_vcpu_get_hsr(struct kvm_vcpu *vcpu) { return vcpu->arch.fault.hsr; diff --git a/arch/arm/kvm/mmio.c b/arch/arm/kvm/mmio.c index 72a12f2..b8e06b7 100644 --- a/arch/arm/kvm/mmio.c +++ b/arch/arm/kvm/mmio.c @@ -86,12 +86,6 @@ static int decode_hsr(struct kvm_vcpu *vcpu, phys_addr_t fault_ipa, sign_extend = kvm_vcpu_dabt_issext(vcpu); rt = kvm_vcpu_dabt_get_rd(vcpu); - if (kvm_vcpu_reg_is_pc(vcpu, rt)) { - /* IO memory trying to read/write pc */ - kvm_inject_pabt(vcpu, kvm_vcpu_get_hfar(vcpu)); - return 1; - } - mmio->is_write = is_write; mmio->phys_addr = fault_ipa; mmio->len = len;
Admitedly, reading a MMIO register to load PC is very weird. Writing PC to a MMIO register is probably even worse. But the architecture doesn't forbid any of these, and injecting a Prefetch Abort is the wrong thing to do anyway. Remove this check altogether, and let the adventurous guest wander into LaLaLand if they feel compelled to do so. Reported-by: Catalin Marinas <catalin.marinas@arm.com> Signed-off-by: Marc Zyngier <marc.zyngier@arm.com> --- arch/arm/include/asm/kvm_emulate.h | 5 ----- arch/arm/kvm/mmio.c | 6 ------ 2 files changed, 11 deletions(-)