From: Marc Zyngier <maz@kernel.org>
Date: Tue, 13 Apr 2021 14:34:15 +0000 (+0100)
Subject: Merge branch 'kvm-arm64/debug-5.13' into kvmarm-master/next
X-Git-Url: http://git.maquefel.me/?a=commitdiff_plain;h=fbb31e5f3ace5386aa13236be77d1b4d481c8c89;p=linux.git

Merge branch 'kvm-arm64/debug-5.13' into kvmarm-master/next

Signed-off-by: Marc Zyngier <maz@kernel.org>
---

fbb31e5f3ace5386aa13236be77d1b4d481c8c89
diff --cc arch/arm64/kvm/debug.c
index 6f992c6969116,2484b2cca74bc..d5e79d7ee6e90
--- a/arch/arm64/kvm/debug.c
+++ b/arch/arm64/kvm/debug.c
@@@ -68,6 -68,64 +68,65 @@@ void kvm_arm_init_debug(void
  	__this_cpu_write(mdcr_el2, kvm_call_hyp_ret(__kvm_get_mdcr_el2));
  }
  
+ /**
+  * kvm_arm_setup_mdcr_el2 - configure vcpu mdcr_el2 value
+  *
+  * @vcpu:	the vcpu pointer
+  *
+  * This ensures we will trap access to:
+  *  - Performance monitors (MDCR_EL2_TPM/MDCR_EL2_TPMCR)
+  *  - Debug ROM Address (MDCR_EL2_TDRA)
+  *  - OS related registers (MDCR_EL2_TDOSA)
+  *  - Statistical profiler (MDCR_EL2_TPMS/MDCR_EL2_E2PB)
+  *  - Self-hosted Trace Filter controls (MDCR_EL2_TTRF)
++ *  - Self-hosted Trace (MDCR_EL2_TTRF/MDCR_EL2_E2TB)
+  */
+ static void kvm_arm_setup_mdcr_el2(struct kvm_vcpu *vcpu)
+ {
+ 	/*
 -	 * This also clears MDCR_EL2_E2PB_MASK to disable guest access
 -	 * to the profiling buffer.
++	 * This also clears MDCR_EL2_E2PB_MASK and MDCR_EL2_E2TB_MASK
++	 * to disable guest access to the profiling and trace buffers
+ 	 */
+ 	vcpu->arch.mdcr_el2 = __this_cpu_read(mdcr_el2) & MDCR_EL2_HPMN_MASK;
+ 	vcpu->arch.mdcr_el2 |= (MDCR_EL2_TPM |
+ 				MDCR_EL2_TPMS |
+ 				MDCR_EL2_TTRF |
+ 				MDCR_EL2_TPMCR |
+ 				MDCR_EL2_TDRA |
+ 				MDCR_EL2_TDOSA);
+ 
+ 	/* Is the VM being debugged by userspace? */
+ 	if (vcpu->guest_debug)
+ 		/* Route all software debug exceptions to EL2 */
+ 		vcpu->arch.mdcr_el2 |= MDCR_EL2_TDE;
+ 
+ 	/*
+ 	 * Trap debug register access when one of the following is true:
+ 	 *  - Userspace is using the hardware to debug the guest
+ 	 *  (KVM_GUESTDBG_USE_HW is set).
+ 	 *  - The guest is not using debug (KVM_ARM64_DEBUG_DIRTY is clear).
+ 	 */
+ 	if ((vcpu->guest_debug & KVM_GUESTDBG_USE_HW) ||
+ 	    !(vcpu->arch.flags & KVM_ARM64_DEBUG_DIRTY))
+ 		vcpu->arch.mdcr_el2 |= MDCR_EL2_TDA;
+ 
+ 	trace_kvm_arm_set_dreg32("MDCR_EL2", vcpu->arch.mdcr_el2);
+ }
+ 
+ /**
+  * kvm_arm_vcpu_init_debug - setup vcpu debug traps
+  *
+  * @vcpu:	the vcpu pointer
+  *
+  * Set vcpu initial mdcr_el2 value.
+  */
+ void kvm_arm_vcpu_init_debug(struct kvm_vcpu *vcpu)
+ {
+ 	preempt_disable();
+ 	kvm_arm_setup_mdcr_el2(vcpu);
+ 	preempt_enable();
+ }
+ 
  /**
   * kvm_arm_reset_debug_ptr - reset the debug ptr to point to the vcpu state
   */