| Message ID | 20171109170021.2984-2-alex.bennee@linaro.org |
|---|---|
| State | New |
| Headers | show |
| Series | KVM: arm64: single step emulation instructions | expand |
On 09/11/17 17:00, Alex Bennée wrote: > After emulating instructions we may want return to user-space to > handle a single-step. If single-step is enabled the helper set the run > structure for return and returns true. > > Signed-off-by: Alex Bennée <alex.bennee@linaro.org> With the fixup: Reviewed-by: Julien Thierry <julien.thierry@arm.com> > > --- > v2 > - kvm_arm_maybe_return_debug -> kvm_arm_handle_step_debug > - return bool, true if return to userspace is required > --- > arch/arm/include/asm/kvm_host.h | 2 ++ > arch/arm64/include/asm/kvm_host.h | 1 + > arch/arm64/kvm/debug.c | 22 ++++++++++++++++++++++ > 3 files changed, 25 insertions(+) > > diff --git a/arch/arm/include/asm/kvm_host.h b/arch/arm/include/asm/kvm_host.h > index 4a879f6ff13b..a2e881d6108e 100644 > --- a/arch/arm/include/asm/kvm_host.h > +++ b/arch/arm/include/asm/kvm_host.h > @@ -285,6 +285,8 @@ static inline void kvm_arm_init_debug(void) {} > static inline void kvm_arm_setup_debug(struct kvm_vcpu *vcpu) {} > static inline void kvm_arm_clear_debug(struct kvm_vcpu *vcpu) {} > static inline void kvm_arm_reset_debug_ptr(struct kvm_vcpu *vcpu) {} > +static inline bool kvm_arm_handle_step_debug(struct kvm_vcpu *vcpu, > + struct kvm_run *run) {} > > int kvm_arm_vcpu_arch_set_attr(struct kvm_vcpu *vcpu, > struct kvm_device_attr *attr); > diff --git a/arch/arm64/include/asm/kvm_host.h b/arch/arm64/include/asm/kvm_host.h > index e923b58606e2..bbfd6a2adb2b 100644 > --- a/arch/arm64/include/asm/kvm_host.h > +++ b/arch/arm64/include/asm/kvm_host.h > @@ -369,6 +369,7 @@ void kvm_arm_init_debug(void); > void kvm_arm_setup_debug(struct kvm_vcpu *vcpu); > void kvm_arm_clear_debug(struct kvm_vcpu *vcpu); > void kvm_arm_reset_debug_ptr(struct kvm_vcpu *vcpu); > +bool kvm_arm_handle_step_debug(struct kvm_vcpu *vcpu, struct kvm_run *run); > int kvm_arm_vcpu_arch_set_attr(struct kvm_vcpu *vcpu, > struct kvm_device_attr *attr); > int kvm_arm_vcpu_arch_get_attr(struct kvm_vcpu *vcpu, > diff --git a/arch/arm64/kvm/debug.c b/arch/arm64/kvm/debug.c > index dbadfaf850a7..95afd22a4634 100644 > --- a/arch/arm64/kvm/debug.c > +++ b/arch/arm64/kvm/debug.c > @@ -221,3 +221,25 @@ void kvm_arm_clear_debug(struct kvm_vcpu *vcpu) > } > } > } > + > + > +/* > + * When KVM has successfully emulated the instruction we might want to > + * return to user space with a KVM_EXIT_DEBUG. We can only do this > + * once the emulation is complete though so for userspace emulations > + * we have to wait until we have re-entered KVM before calling this > + * helper. > + * > + * Return true (and set exit_reason) to return to userspace or false > + * if no further action required. > + */ > + > +bool kvm_arm_handle_step_debug(struct kvm_vcpu *vcpu, struct kvm_run *run) > +{ > + if (vcpu->guest_debug & KVM_GUESTDBG_SINGLESTEP) { > + run->exit_reason = KVM_EXIT_DEBUG; > + run->debug.arch.hsr = ESR_ELx_EC_SOFTSTP_LOW << ESR_ELx_EC_SHIFT; > + return true; > + } > + return false; > +} >
diff --git a/arch/arm/include/asm/kvm_host.h b/arch/arm/include/asm/kvm_host.h index 4a879f6ff13b..a2e881d6108e 100644 --- a/arch/arm/include/asm/kvm_host.h +++ b/arch/arm/include/asm/kvm_host.h @@ -285,6 +285,8 @@ static inline void kvm_arm_init_debug(void) {} static inline void kvm_arm_setup_debug(struct kvm_vcpu *vcpu) {} static inline void kvm_arm_clear_debug(struct kvm_vcpu *vcpu) {} static inline void kvm_arm_reset_debug_ptr(struct kvm_vcpu *vcpu) {} +static inline bool kvm_arm_handle_step_debug(struct kvm_vcpu *vcpu, + struct kvm_run *run) {} int kvm_arm_vcpu_arch_set_attr(struct kvm_vcpu *vcpu, struct kvm_device_attr *attr); diff --git a/arch/arm64/include/asm/kvm_host.h b/arch/arm64/include/asm/kvm_host.h index e923b58606e2..bbfd6a2adb2b 100644 --- a/arch/arm64/include/asm/kvm_host.h +++ b/arch/arm64/include/asm/kvm_host.h @@ -369,6 +369,7 @@ void kvm_arm_init_debug(void); void kvm_arm_setup_debug(struct kvm_vcpu *vcpu); void kvm_arm_clear_debug(struct kvm_vcpu *vcpu); void kvm_arm_reset_debug_ptr(struct kvm_vcpu *vcpu); +bool kvm_arm_handle_step_debug(struct kvm_vcpu *vcpu, struct kvm_run *run); int kvm_arm_vcpu_arch_set_attr(struct kvm_vcpu *vcpu, struct kvm_device_attr *attr); int kvm_arm_vcpu_arch_get_attr(struct kvm_vcpu *vcpu, diff --git a/arch/arm64/kvm/debug.c b/arch/arm64/kvm/debug.c index dbadfaf850a7..95afd22a4634 100644 --- a/arch/arm64/kvm/debug.c +++ b/arch/arm64/kvm/debug.c @@ -221,3 +221,25 @@ void kvm_arm_clear_debug(struct kvm_vcpu *vcpu) } } } + + +/* + * When KVM has successfully emulated the instruction we might want to + * return to user space with a KVM_EXIT_DEBUG. We can only do this + * once the emulation is complete though so for userspace emulations + * we have to wait until we have re-entered KVM before calling this + * helper. + * + * Return true (and set exit_reason) to return to userspace or false + * if no further action required. + */ + +bool kvm_arm_handle_step_debug(struct kvm_vcpu *vcpu, struct kvm_run *run) +{ + if (vcpu->guest_debug & KVM_GUESTDBG_SINGLESTEP) { + run->exit_reason = KVM_EXIT_DEBUG; + run->debug.arch.hsr = ESR_ELx_EC_SOFTSTP_LOW << ESR_ELx_EC_SHIFT; + return true; + } + return false; +}
After emulating instructions we may want return to user-space to handle a single-step. If single-step is enabled the helper set the run structure for return and returns true. Signed-off-by: Alex Bennée <alex.bennee@linaro.org> --- v2 - kvm_arm_maybe_return_debug -> kvm_arm_handle_step_debug - return bool, true if return to userspace is required --- arch/arm/include/asm/kvm_host.h | 2 ++ arch/arm64/include/asm/kvm_host.h | 1 + arch/arm64/kvm/debug.c | 22 ++++++++++++++++++++++ 3 files changed, 25 insertions(+)