Merge branch 'x86/urgent' into core/efi, to pick up a pending EFI fix

[karo-tx-linux.git] / arch / arm64 / kvm / debug.c

diff --git a/arch/arm64/kvm/debug.c b/arch/arm64/kvm/debug.c
index e0947b77faaab4ca39eba43be2766c0d60a4c961..47e5f0feaee82c05ac1b56bd89f9acd0edffa82d 100644 (file)
--- a/arch/arm64/kvm/debug.c
+++ b/arch/arm64/kvm/debug.c
@@ -18,12 +18,15 @@
  */
 
 #include <linux/kvm_host.h>
+#include <linux/hw_breakpoint.h>
 
 #include <asm/debug-monitors.h>
 #include <asm/kvm_asm.h>
 #include <asm/kvm_arm.h>
 #include <asm/kvm_emulate.h>
 
+#include "trace.h"
+
 /* These are the bits of MDSCR_EL1 we may manipulate */
 #define MDSCR_EL1_DEBUG_MASK   (DBG_MDSCR_SS | \
                                DBG_MDSCR_KDE | \
@@ -44,11 +47,17 @@ static DEFINE_PER_CPU(u32, mdcr_el2);
 static void save_guest_debug_regs(struct kvm_vcpu *vcpu)
 {
        vcpu->arch.guest_debug_preserved.mdscr_el1 = vcpu_sys_reg(vcpu, MDSCR_EL1);
+
+       trace_kvm_arm_set_dreg32("Saved MDSCR_EL1",
+                               vcpu->arch.guest_debug_preserved.mdscr_el1);
 }
 
 static void restore_guest_debug_regs(struct kvm_vcpu *vcpu)
 {
        vcpu_sys_reg(vcpu, MDSCR_EL1) = vcpu->arch.guest_debug_preserved.mdscr_el1;
+
+       trace_kvm_arm_set_dreg32("Restored MDSCR_EL1",
+                               vcpu_sys_reg(vcpu, MDSCR_EL1));
 }
 
 /**
@@ -99,16 +108,14 @@ void kvm_arm_setup_debug(struct kvm_vcpu *vcpu)
 {
        bool trap_debug = !(vcpu->arch.debug_flags & KVM_ARM64_DEBUG_DIRTY);
 
+       trace_kvm_arm_setup_debug(vcpu, vcpu->guest_debug);
+
        vcpu->arch.mdcr_el2 = __this_cpu_read(mdcr_el2) & MDCR_EL2_HPMN_MASK;
        vcpu->arch.mdcr_el2 |= (MDCR_EL2_TPM |
                                MDCR_EL2_TPMCR |
                                MDCR_EL2_TDRA |
                                MDCR_EL2_TDOSA);
 
-       /* Trap on access to debug registers? */
-       if (trap_debug)
-               vcpu->arch.mdcr_el2 |= MDCR_EL2_TDA;
-
        /* Is Guest debugging in effect? */
        if (vcpu->guest_debug) {
                /* Route all software debug exceptions to EL2 */
@@ -143,11 +150,68 @@ void kvm_arm_setup_debug(struct kvm_vcpu *vcpu)
                } else {
                        vcpu_sys_reg(vcpu, MDSCR_EL1) &= ~DBG_MDSCR_SS;
                }
+
+               trace_kvm_arm_set_dreg32("SPSR_EL2", *vcpu_cpsr(vcpu));
+
+               /*
+                * HW Breakpoints and watchpoints
+                *
+                * We simply switch the debug_ptr to point to our new
+                * external_debug_state which has been populated by the
+                * debug ioctl. The existing KVM_ARM64_DEBUG_DIRTY
+                * mechanism ensures the registers are updated on the
+                * world switch.
+                */
+               if (vcpu->guest_debug & KVM_GUESTDBG_USE_HW) {
+                       /* Enable breakpoints/watchpoints */
+                       vcpu_sys_reg(vcpu, MDSCR_EL1) |= DBG_MDSCR_MDE;
+
+                       vcpu->arch.debug_ptr = &vcpu->arch.external_debug_state;
+                       vcpu->arch.debug_flags |= KVM_ARM64_DEBUG_DIRTY;
+                       trap_debug = true;
+
+                       trace_kvm_arm_set_regset("BKPTS", get_num_brps(),
+                                               &vcpu->arch.debug_ptr->dbg_bcr[0],
+                                               &vcpu->arch.debug_ptr->dbg_bvr[0]);
+
+                       trace_kvm_arm_set_regset("WAPTS", get_num_wrps(),
+                                               &vcpu->arch.debug_ptr->dbg_wcr[0],
+                                               &vcpu->arch.debug_ptr->dbg_wvr[0]);
+               }
        }
+
+       BUG_ON(!vcpu->guest_debug &&
+               vcpu->arch.debug_ptr != &vcpu->arch.vcpu_debug_state);
+
+       /* Trap debug register access */
+       if (trap_debug)
+               vcpu->arch.mdcr_el2 |= MDCR_EL2_TDA;
+
+       trace_kvm_arm_set_dreg32("MDCR_EL2", vcpu->arch.mdcr_el2);
+       trace_kvm_arm_set_dreg32("MDSCR_EL1", vcpu_sys_reg(vcpu, MDSCR_EL1));
 }
 
 void kvm_arm_clear_debug(struct kvm_vcpu *vcpu)
 {
-       if (vcpu->guest_debug)
+       trace_kvm_arm_clear_debug(vcpu->guest_debug);
+
+       if (vcpu->guest_debug) {
                restore_guest_debug_regs(vcpu);
+
+               /*
+                * If we were using HW debug we need to restore the
+                * debug_ptr to the guest debug state.
+                */
+               if (vcpu->guest_debug & KVM_GUESTDBG_USE_HW) {
+                       kvm_arm_reset_debug_ptr(vcpu);
+
+                       trace_kvm_arm_set_regset("BKPTS", get_num_brps(),
+                                               &vcpu->arch.debug_ptr->dbg_bcr[0],
+                                               &vcpu->arch.debug_ptr->dbg_bvr[0]);
+
+                       trace_kvm_arm_set_regset("WAPTS", get_num_wrps(),
+                                               &vcpu->arch.debug_ptr->dbg_wcr[0],
+                                               &vcpu->arch.debug_ptr->dbg_wvr[0]);
+               }
+       }
 }