Re: [PATCH v1 2/2] kvm: arm64: handle single-step of userspace mmio instructions

[Date Prev][Date Next][Thread Prev][Thread Next][Date Index][Thread Index]

 





On 06/10/17 12:39, Alex Bennée wrote:
The system state of KVM when using userspace emulation is not complete
until we return into KVM_RUN. To handle mmio related updates we wait
until they have been committed and then schedule our KVM_EXIT_DEBUG.

I've introduced a new function kvm_arm_maybe_return_debug() to wrap up
the differences between arm/arm64 which is currently null for arm.

Signed-off-by: Alex Bennée <alex.bennee@xxxxxxxxxx>
---
  arch/arm/include/asm/kvm_host.h   |  2 ++
  arch/arm64/include/asm/kvm_host.h |  1 +
  arch/arm64/kvm/debug.c            | 21 +++++++++++++++++++++
  arch/arm64/kvm/handle_exit.c      |  9 +++------
  virt/kvm/arm/arm.c                |  2 +-
  virt/kvm/arm/mmio.c               |  3 ++-
  6 files changed, 30 insertions(+), 8 deletions(-)

diff --git a/arch/arm/include/asm/kvm_host.h b/arch/arm/include/asm/kvm_host.h
index 4a879f6ff13b..aec943f6d123 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 int  kvm_arm_maybe_return_debug(struct kvm_vcpu *vcpu,
+						struct kvm_run *run) {}

This function should return 1.

  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..fa67d21662f6 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);
+int  kvm_arm_maybe_return_debug(struct kvm_vcpu *vcpu, struct kvm_run *run);

I feel the name could be a little bit more explicit:

kvm_arm_trap_need_step_debug, kvm_arm_trap_step_return_debug, kvm_arm_trap_need_return_debug.

At least, I think it would be nice that the name reflect that this check is meant for emulated instructions.

Otherwise:

Reviewed-by: Julien Thierry <julien.thierry@xxxxxxx>

Thanks,

--
Julien Thierry



[Index of Archives]     [KVM ARM]     [KVM ia64]     [KVM ppc]     [Virtualization Tools]     [Spice Development]     [Libvirt]     [Libvirt Users]     [Linux USB Devel]     [Linux Audio Users]     [Yosemite Questions]     [Linux Kernel]     [Linux SCSI]     [XFree86]

  Powered by Linux