From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S965222AbdKPPjc (ORCPT ); Thu, 16 Nov 2017 10:39:32 -0500 Received: from mail-wm0-f65.google.com ([74.125.82.65]:39202 "EHLO mail-wm0-f65.google.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S935613AbdKPPjZ (ORCPT ); Thu, 16 Nov 2017 10:39:25 -0500 X-Google-Smtp-Source: AGs4zMbvWL7R+u42puXSWY8J/RksmOMdsZFjnMFtn1YTsSTo7Ra26f2NXRkT2TjCaV4KRjP5mPN7Zw== From: =?UTF-8?q?Alex=20Benn=C3=A9e?= To: julien.thierry@arm.com, kvm@vger.kernel.org, linux-arm-kernel@lists.infradead.org, kvmarm@lists.cs.columbia.edu, christoffer.dall@linaro.org, marc.zyngier@arm.com Cc: =?UTF-8?q?Alex=20Benn=C3=A9e?= , Russell King , Catalin Marinas , Will Deacon , linux-kernel@vger.kernel.org (open list) Subject: [PATCH v3 1/3] kvm: arm debug: introduce helper for single-step Date: Thu, 16 Nov 2017 15:39:19 +0000 Message-Id: <20171116153921.21991-2-alex.bennee@linaro.org> X-Mailer: git-send-email 2.15.0 In-Reply-To: <20171116153921.21991-1-alex.bennee@linaro.org> References: <20171116153921.21991-1-alex.bennee@linaro.org> MIME-Version: 1.0 Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 8bit Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org 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 Reviewed-by: Julien Thierry --- 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 | 5 +++++ arch/arm64/include/asm/kvm_host.h | 1 + arch/arm64/kvm/debug.c | 22 ++++++++++++++++++++++ 3 files changed, 28 insertions(+) diff --git a/arch/arm/include/asm/kvm_host.h b/arch/arm/include/asm/kvm_host.h index 4a879f6ff13b..26a1ea6c6542 100644 --- a/arch/arm/include/asm/kvm_host.h +++ b/arch/arm/include/asm/kvm_host.h @@ -285,6 +285,11 @@ 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) +{ + return false; +} 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; +} -- 2.15.0