This patch adds the debug stub support on booke/bookehv.
Now QEMU debug stub can use hw breakpoint, watchpoint and
software breakpoint to debug guest.
Signed-off-by: Bharat Bhushan <bharat.bhushan@xxxxxxxxxxxxx>
---
arch/powerpc/include/uapi/asm/kvm.h | 22 +++++-
arch/powerpc/kvm/booke.c | 143 +++++++++++++++++++++++++++++++---
arch/powerpc/kvm/e500_emulate.c | 6 ++
arch/powerpc/kvm/e500mc.c | 3 +-
4 files changed, 155 insertions(+), 19 deletions(-)
diff --git a/arch/powerpc/include/uapi/asm/kvm.h b/arch/powerpc/include/uapi/asm/kvm.h
index 15f9a00..d7ce449 100644
--- a/arch/powerpc/include/uapi/asm/kvm.h
+++ b/arch/powerpc/include/uapi/asm/kvm.h
@@ -25,6 +25,7 @@
/* Select powerpc specific features in <linux/kvm.h> */
#define __KVM_HAVE_SPAPR_TCE
#define __KVM_HAVE_PPC_SMT
+#define __KVM_HAVE_GUEST_DEBUG
struct kvm_regs {
__u64 pc;
@@ -267,7 +268,24 @@ struct kvm_fpu {
__u64 fpr[32];
};
+/*
+ * Defines for h/w breakpoint, watchpoint (read, write or both) and
+ * software breakpoint.
+ * These are used as "type" in KVM_SET_GUEST_DEBUG ioctl and "status"
+ * for KVM_DEBUG_EXIT.
+ */
+#define KVMPPC_DEBUG_NONE 0x0
+#define KVMPPC_DEBUG_BREAKPOINT (1UL << 1)
+#define KVMPPC_DEBUG_WATCH_WRITE (1UL << 2)
+#define KVMPPC_DEBUG_WATCH_READ (1UL << 3)
struct kvm_debug_exit_arch {
+ __u64 address;
+ /*
+ * exiting to userspace because of h/w breakpoint, watchpoint
+ * (read, write or both) and software breakpoint.
+ */
+ __u32 status;
+ __u32 reserved;
};
/* for KVM_SET_GUEST_DEBUG */
@@ -279,10 +297,6 @@ struct kvm_guest_debug_arch {
* Type denotes h/w breakpoint, read watchpoint, write
* watchpoint or watchpoint (both read and write).
*/
-#define KVMPPC_DEBUG_NOTYPE 0x0
-#define KVMPPC_DEBUG_BREAKPOINT (1UL << 1)
-#define KVMPPC_DEBUG_WATCH_WRITE (1UL << 2)
-#define KVMPPC_DEBUG_WATCH_READ (1UL << 3)
__u32 type;
__u32 reserved;
} bp[16];
diff --git a/arch/powerpc/kvm/booke.c b/arch/powerpc/kvm/booke.c
index 1de93a8..21b0313 100644
--- a/arch/powerpc/kvm/booke.c
+++ b/arch/powerpc/kvm/booke.c
@@ -133,6 +133,30 @@ static void kvmppc_vcpu_sync_fpu(struct kvm_vcpu *vcpu)
#endif
}
+static void kvmppc_vcpu_sync_debug(struct kvm_vcpu *vcpu)
+{
+ /* Synchronize guest's desire to get debug interrupts into shadow MSR */
+#ifndef CONFIG_KVM_BOOKE_HV
+ vcpu->arch.shadow_msr &= ~MSR_DE;
+ vcpu->arch.shadow_msr |= vcpu->arch.shared->msr & MSR_DE;
+#endif
+
+ /* Force enable debug interrupts when user space wants to debug */
+ if (vcpu->guest_debug) {
+#ifdef CONFIG_KVM_BOOKE_HV
+ /*
+ * Since there is no shadow MSR, sync MSR_DE into the guest
+ * visible MSR. Do not allow guest to change MSR[DE].
+ */
+ vcpu->arch.shared->msr |= MSR_DE;
+ mtspr(SPRN_MSRP, mfspr(SPRN_MSRP) | MSRP_DEP);
+#else
+ vcpu->arch.shadow_msr |= MSR_DE;
+ vcpu->arch.shared->msr &= ~MSR_DE;
+#endif
+ }
+}
+
/*
* Helper function for "full" MSR writes. No need to call this if only
* EE/CE/ME/DE/RI are changing.
@@ -150,6 +174,7 @@ void kvmppc_set_msr(struct kvm_vcpu *vcpu, u32 new_msr)
kvmppc_mmu_msr_notify(vcpu, old_msr);
kvmppc_vcpu_sync_spe(vcpu);
kvmppc_vcpu_sync_fpu(vcpu);
+ kvmppc_vcpu_sync_debug(vcpu);
}
static void kvmppc_booke_queue_irqprio(struct kvm_vcpu *vcpu,
@@ -736,6 +761,13 @@ static int emulation_exit(struct kvm_run *run, struct kvm_vcpu *vcpu)
run->exit_reason = KVM_EXIT_DCR;
return RESUME_HOST;
+ case EMULATE_EXIT_USER:
+ run->exit_reason = KVM_EXIT_DEBUG;
+ run->debug.arch.address = vcpu->arch.pc;
+ run->debug.arch.status = 0;
+ kvmppc_account_exit(vcpu, DEBUG_EXITS);
+ return RESUME_HOST;
+
case EMULATE_FAIL:
printk(KERN_CRIT "%s: emulation at %lx failed (%08x)\n",
__func__, vcpu->arch.pc, vcpu->arch.last_inst);
@@ -751,6 +783,28 @@ static int emulation_exit(struct kvm_run *run, struct kvm_vcpu *vcpu)
}
}
+static int kvmppc_handle_debug(struct kvm_run *run, struct kvm_vcpu *vcpu)
+{
+ u32 dbsr = vcpu->arch.dbsr;
+ run->debug.arch.status = 0;
+ run->debug.arch.address = vcpu->arch.pc;
+
+ if (dbsr & (DBSR_IAC1 | DBSR_IAC2 | DBSR_IAC3 | DBSR_IAC4)) {
+ run->debug.arch.status |= KVMPPC_DEBUG_BREAKPOINT;
+ } else {
+ if (dbsr & (DBSR_DAC1W | DBSR_DAC2W))
+ run->debug.arch.status |= KVMPPC_DEBUG_WATCH_WRITE;
+ else if (dbsr & (DBSR_DAC1R | DBSR_DAC2R))
+ run->debug.arch.status |= KVMPPC_DEBUG_WATCH_READ;
+ if (dbsr & (DBSR_DAC1R | DBSR_DAC1W))
+ run->debug.arch.address = vcpu->arch.shadow_dbg_reg.dac[0];
+ else if (dbsr & (DBSR_DAC2R | DBSR_DAC2W))
+ run->debug.arch.address = vcpu->arch.shadow_dbg_reg.dac[1];
+ }
+
+ return RESUME_HOST;
+}
+
static void kvmppc_fill_pt_regs(struct pt_regs *regs)
{
ulong r1, ip, msr, lr;
@@ -1110,18 +1164,11 @@ int kvmppc_handle_exit(struct kvm_run *run, struct kvm_vcpu *vcpu,
}
case BOOKE_INTERRUPT_DEBUG: {
- u32 dbsr;
-
- vcpu->arch.pc = mfspr(SPRN_CSRR0);
-
- /* clear IAC events in DBSR register */
- dbsr = mfspr(SPRN_DBSR);
- dbsr &= DBSR_IAC1 | DBSR_IAC2 | DBSR_IAC3 | DBSR_IAC4;
- mtspr(SPRN_DBSR, dbsr);
-
- run->exit_reason = KVM_EXIT_DEBUG;
+ r = kvmppc_handle_debug(run, vcpu);
+ if (r == RESUME_HOST) {
+ run->exit_reason = KVM_EXIT_DEBUG;
+ }
kvmppc_account_exit(vcpu, DEBUG_EXITS);
- r = RESUME_HOST;
break;
}
@@ -1172,7 +1219,7 @@ int kvm_arch_vcpu_setup(struct kvm_vcpu *vcpu)
kvmppc_set_msr(vcpu, 0);
#ifndef CONFIG_KVM_BOOKE_HV
- vcpu->arch.shadow_msr = MSR_USER | MSR_DE | MSR_IS | MSR_DS;
+ vcpu->arch.shadow_msr = MSR_USER | MSR_IS | MSR_DS;
vcpu->arch.shadow_pid = 1;
vcpu->arch.shared->msr = 0;
#endif
@@ -1527,10 +1574,80 @@ int kvm_vcpu_ioctl_set_one_reg(struct kvm_vcpu *vcpu, struct kvm_one_reg *reg)
return r;
}
+#define BP_NUM KVMPPC_BOOKE_IAC_NUM
+#define WP_NUM KVMPPC_BOOKE_DAC_NUM
+
int kvm_arch_vcpu_ioctl_set_guest_debug(struct kvm_vcpu *vcpu,
struct kvm_guest_debug *dbg)
{
- return -EINVAL;
+
+ if (!(dbg->control & KVM_GUESTDBG_ENABLE)) {
+ /* Clear All debug events */
+ vcpu->arch.shadow_dbg_reg.dbcr0 = 0;
+ vcpu->guest_debug = 0;
+ return 0;
+ }
+
+ vcpu->guest_debug = dbg->control;
+ vcpu->arch.shadow_dbg_reg.dbcr0 = 0;
+ /* Set DBCR0_EDM in guest visible DBCR0 register. */
+ vcpu->arch.dbg_reg.dbcr0 = DBCR0_EDM;
+
+ if (vcpu->guest_debug & KVM_GUESTDBG_SINGLESTEP)
+ vcpu->arch.shadow_dbg_reg.dbcr0 |= DBCR0_IDM | DBCR0_IC;
+
+ if (vcpu->guest_debug & KVM_GUESTDBG_USE_HW_BP) {
+ struct kvmppc_booke_debug_reg *gdbgr =
+ &(vcpu->arch.shadow_dbg_reg);
+ int n, b = 0, w = 0;
+ const u32 bp_code[] = {
+ DBCR0_IAC1 | DBCR0_IDM,
+ DBCR0_IAC2 | DBCR0_IDM,
+ DBCR0_IAC3 | DBCR0_IDM,
+ DBCR0_IAC4 | DBCR0_IDM
+ };
+ const u32 wp_code[] = {
+ DBCR0_DAC1W | DBCR0_IDM,
+ DBCR0_DAC2W | DBCR0_IDM,
+ DBCR0_DAC1R | DBCR0_IDM,
+ DBCR0_DAC2R | DBCR0_IDM
+ };
+
+#ifndef CONFIG_KVM_BOOKE_HV
+ gdbgr->dbcr1 = DBCR1_IAC1US | DBCR1_IAC2US |
+ DBCR1_IAC3US | DBCR1_IAC4US;
+ gdbgr->dbcr2 = DBCR2_DAC1US | DBCR2_DAC2US;
+#else
+ gdbgr->dbcr1 = 0;
+ gdbgr->dbcr2 = 0;
+#endif
+
+ for (n = 0; n < (BP_NUM + WP_NUM); n++) {
+ u32 type = dbg->arch.bp[n].type;
+
+ if (!type)
+ break;
+
+ if (type & (KVMPPC_DEBUG_WATCH_READ |
+ KVMPPC_DEBUG_WATCH_WRITE)) {
+ if (w < WP_NUM) {
+ if (type & KVMPPC_DEBUG_WATCH_READ)
+ gdbgr->dbcr0 |= wp_code[w + 2];
+ if (type & KVMPPC_DEBUG_WATCH_WRITE)
+ gdbgr->dbcr0 |= wp_code[w];
+ gdbgr->dac[w] = dbg->arch.bp[n].addr;
+ w++;
+ }
+ } else if (type & KVMPPC_DEBUG_BREAKPOINT) {
+ if (b < BP_NUM) {
+ gdbgr->dbcr0 |= bp_code[b];
+ gdbgr->iac[b] = dbg->arch.bp[n].addr;
+ b++;
+ }
+ }
+ }
+ }
+ return 0;
}
int kvm_arch_vcpu_ioctl_get_fpu(struct kvm_vcpu *vcpu, struct kvm_fpu *fpu)
diff --git a/arch/powerpc/kvm/e500_emulate.c b/arch/powerpc/kvm/e500_emulate.c
index e78f353..83ac877 100644
--- a/arch/powerpc/kvm/e500_emulate.c
+++ b/arch/powerpc/kvm/e500_emulate.c
@@ -26,6 +26,7 @@
#define XOP_TLBRE 946
#define XOP_TLBWE 978
#define XOP_TLBILX 18
+#define XOP_EHPRIV 270
#ifdef CONFIG_KVM_E500MC
static int dbell2prio(ulong param)
@@ -130,6 +131,11 @@ int kvmppc_core_emulate_op(struct kvm_run *run, struct kvm_vcpu *vcpu,
emulated = kvmppc_e500_emul_tlbivax(vcpu, ea);
break;
+ case XOP_EHPRIV:
+ emulated = EMULATE_EXIT_USER;
+ *advance = 0;
+ break;
+
default:
emulated = EMULATE_FAIL;
}
diff --git a/arch/powerpc/kvm/e500mc.c b/arch/powerpc/kvm/e500mc.c
index 1f89d26..f5fc6f5 100644
--- a/arch/powerpc/kvm/e500mc.c
+++ b/arch/powerpc/kvm/e500mc.c
@@ -182,8 +182,7 @@ int kvmppc_core_vcpu_setup(struct kvm_vcpu *vcpu)
{
struct kvmppc_vcpu_e500 *vcpu_e500 = to_e500(vcpu);
- vcpu->arch.shadow_epcr = SPRN_EPCR_DSIGS | SPRN_EPCR_DGTMI | \
- SPRN_EPCR_DUVD;
+ vcpu->arch.shadow_epcr = SPRN_EPCR_DSIGS | SPRN_EPCR_DGTMI;
#ifdef CONFIG_64BIT
vcpu->arch.shadow_epcr |= SPRN_EPCR_ICM;
#endif
--
1.7.0.4
--
To unsubscribe from this list: send the line "unsubscribe kvm" in
the body of a message to majordomo@xxxxxxxxxxxxxxx
More majordomo info at http://vger.kernel.org/majordomo-info.html
