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 <[email protected]>
---
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;
+}
--
2.14.2
From 1583890201878294128@xxx Sun Nov 12 19:36:45 +0000 2017
X-GM-THRID: 1583890201878294128
X-Gmail-Labels: Inbox,Category Forums,HistoricalUnread
---
arch/arm/include/asm/kvm_host.h | 5 ++++-
1 file changed, 4 insertions(+), 1 deletion(-)
diff --git a/arch/arm/include/asm/kvm_host.h b/arch/arm/include/asm/kvm_host.h
index a2e881d6108e..26a1ea6c6542 100644
--- a/arch/arm/include/asm/kvm_host.h
+++ b/arch/arm/include/asm/kvm_host.h
@@ -286,7 +286,10 @@ 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) {}
+ struct kvm_run *run)
+{
+ return false;
+}
int kvm_arm_vcpu_arch_set_attr(struct kvm_vcpu *vcpu,
struct kvm_device_attr *attr);
--
2.14.2
From 1583622345787379232@xxx Thu Nov 09 20:39:18 +0000 2017
X-GM-THRID: 1583622345787379232
X-Gmail-Labels: Inbox,Category Forums,HistoricalUnread