[RFC PATCH 42/73] KVM: x86/PVM: Support for kvm_exit() tracepoint

Lai Jiangshan
2024-02-26T14:36:55Z

From: Hou Wenlong <houwenlong.hwl@antgroup.com>

Similar to VMX/SVM, add necessary information to support kvm_exit()
tracepoint.

Suggested-by: Lai Jiangshan <jiangshan.ljs@antgroup.com>
Signed-off-by: Hou Wenlong <houwenlong.hwl@antgroup.com>
Signed-off-by: Lai Jiangshan <jiangshan.ljs@antgroup.com>
---
arch/x86/kvm/pvm/pvm.c | 41 +++++++++++++++++++++++++++++++++++++++++
arch/x86/kvm/pvm/pvm.h | 35 +++++++++++++++++++++++++++++++++++
arch/x86/kvm/trace.h | 7 ++++++-
3 files changed, 82 insertions(+), 1 deletion(-)

diff --git a/arch/x86/kvm/pvm/pvm.c b/arch/x86/kvm/pvm/pvm.c
index e68052f33186..6ac599587567 100644
--- a/arch/x86/kvm/pvm/pvm.c
+++ b/arch/x86/kvm/pvm/pvm.c
@@ -1996,6 +1996,43 @@ static int pvm_handle_exit(struct kvm_vcpu *vcpu, fastpath_t exit_fastpath)
return 0;
}

+static u32 pvm_get_syscall_exit_reason(struct kvm_vcpu *vcpu)
+{
+ struct vcpu_pvm *pvm = to_pvm(vcpu);
+ unsigned long rip = kvm_rip_read(vcpu);
+
+ if (is_smod(pvm)) {
+ if (rip == pvm->msr_retu_rip_plus2)
+ return PVM_EXIT_REASONS_ERETU;
+ else if (rip == pvm->msr_rets_rip_plus2)
+ return PVM_EXIT_REASONS_ERETS;
+ else
+ return PVM_EXIT_REASONS_HYPERCALL;
+ }
+
+ return PVM_EXIT_REASONS_SYSCALL;
+}
+
+static void pvm_get_exit_info(struct kvm_vcpu *vcpu, u32 *reason, u64 *info1, u64 *info2,
+ u32 *intr_info, u32 *error_code)
+{
+ struct vcpu_pvm *pvm = to_pvm(vcpu);
+
+ if (pvm->exit_vector == PVM_SYSCALL_VECTOR)
+ *reason = pvm_get_syscall_exit_reason(vcpu);
+ else if (pvm->exit_vector == IA32_SYSCALL_VECTOR)
+ *reason = PVM_EXIT_REASONS_INT80;
+ else if (pvm->exit_vector >= FIRST_EXTERNAL_VECTOR &&
+ pvm->exit_vector < NR_VECTORS)
+ *reason = PVM_EXIT_REASONS_INTERRUPT;
+ else
+ *reason = pvm->exit_vector;
+ *info1 = pvm->exit_vector;
+ *info2 = pvm->exit_error_code;
+ *intr_info = pvm->exit_vector;
+ *error_code = pvm->exit_error_code;
+}
+
static void pvm_handle_exit_irqoff(struct kvm_vcpu *vcpu)
{
struct vcpu_pvm *pvm = to_pvm(vcpu);
@@ -2298,6 +2335,8 @@ static fastpath_t pvm_vcpu_run(struct kvm_vcpu *vcpu)
mark_page_dirty_in_slot(vcpu->kvm, pvm->pvcs_gpc.memslot,
pvm->pvcs_gpc.gpa >> PAGE_SHIFT);

+ trace_kvm_exit(vcpu, KVM_ISA_PVM);
+
return EXIT_FASTPATH_NONE;
}

@@ -2627,6 +2666,8 @@ static struct kvm_x86_ops pvm_x86_ops __initdata = {
.refresh_apicv_exec_ctrl = pvm_refresh_apicv_exec_ctrl,
.deliver_interrupt = pvm_deliver_interrupt,

+ .get_exit_info = pvm_get_exit_info,
+
.vcpu_after_set_cpuid = pvm_vcpu_after_set_cpuid,

.check_intercept = pvm_check_intercept,
diff --git a/arch/x86/kvm/pvm/pvm.h b/arch/x86/kvm/pvm/pvm.h
index f28ab0b48f40..2f8fdb0ae3df 100644
--- a/arch/x86/kvm/pvm/pvm.h
+++ b/arch/x86/kvm/pvm/pvm.h
@@ -10,6 +10,41 @@
#define PVM_SYSCALL_VECTOR SWITCH_EXIT_REASONS_SYSCALL
#define PVM_FAILED_VMENTRY_VECTOR SWITCH_EXIT_REASONS_FAILED_VMETNRY

+#define PVM_EXIT_REASONS_SHIFT 16
+#define PVM_EXIT_REASONS_SYSCALL (1UL << PVM_EXIT_REASONS_SHIFT)
+#define PVM_EXIT_REASONS_HYPERCALL (2UL << PVM_EXIT_REASONS_SHIFT)
+#define PVM_EXIT_REASONS_ERETU (3UL << PVM_EXIT_REASONS_SHIFT)
+#define PVM_EXIT_REASONS_ERETS (4UL << PVM_EXIT_REASONS_SHIFT)
+#define PVM_EXIT_REASONS_INTERRUPT (5UL << PVM_EXIT_REASONS_SHIFT)
+#define PVM_EXIT_REASONS_INT80 (6UL << PVM_EXIT_REASONS_SHIFT)
+
+#define PVM_EXIT_REASONS \
+ { DE_VECTOR, "DE excp" }, \
+ { DB_VECTOR, "DB excp" }, \
+ { NMI_VECTOR, "NMI excp" }, \
+ { BP_VECTOR, "BP excp" }, \
+ { OF_VECTOR, "OF excp" }, \
+ { BR_VECTOR, "BR excp" }, \
+ { UD_VECTOR, "UD excp" }, \
+ { NM_VECTOR, "NM excp" }, \
+ { DF_VECTOR, "DF excp" }, \
+ { TS_VECTOR, "TS excp" }, \
+ { SS_VECTOR, "SS excp" }, \
+ { GP_VECTOR, "GP excp" }, \
+ { PF_VECTOR, "PF excp" }, \
+ { MF_VECTOR, "MF excp" }, \
+ { AC_VECTOR, "AC excp" }, \
+ { MC_VECTOR, "MC excp" }, \
+ { XM_VECTOR, "XM excp" }, \
+ { VE_VECTOR, "VE excp" }, \
+ { PVM_EXIT_REASONS_SYSCALL, "SYSCALL" }, \
+ { PVM_EXIT_REASONS_HYPERCALL, "HYPERCALL" }, \
+ { PVM_EXIT_REASONS_ERETU, "ERETU" }, \
+ { PVM_EXIT_REASONS_ERETS, "ERETS" }, \
+ { PVM_EXIT_REASONS_INTERRUPT, "INTERRUPT" }, \
+ { PVM_EXIT_REASONS_INT80, "INT80" }, \
+ { PVM_FAILED_VMENTRY_VECTOR, "FAILED_VMENTRY" }
+
#define PT_L4_SHIFT 39
#define PT_L4_SIZE (1UL << PT_L4_SHIFT)
#define DEFAULT_RANGE_L4_SIZE (32 * PT_L4_SIZE)
diff --git a/arch/x86/kvm/trace.h b/arch/x86/kvm/trace.h
index 83843379813e..3d6549679e98 100644
--- a/arch/x86/kvm/trace.h
+++ b/arch/x86/kvm/trace.h
@@ -8,6 +8,8 @@
#include <asm/clocksource.h>
#include <asm/pvclock-abi.h>

+#include "pvm/pvm.h"
+
#undef TRACE_SYSTEM
#define TRACE_SYSTEM kvm

@@ -282,11 +284,14 @@ TRACE_EVENT(kvm_apic,

#define KVM_ISA_VMX 1
#define KVM_ISA_SVM 2
+#define KVM_ISA_PVM 3

#define kvm_print_exit_reason(exit_reason, isa) \
(isa == KVM_ISA_VMX) ? \
__print_symbolic(exit_reason & 0xffff, VMX_EXIT_REASONS) : \
- __print_symbolic(exit_reason, SVM_EXIT_REASONS), \
+ ((isa == KVM_ISA_SVM) ? \
+ __print_symbolic(exit_reason, SVM_EXIT_REASONS) : \
+ __print_symbolic(exit_reason, PVM_EXIT_REASONS)), \
(isa == KVM_ISA_VMX && exit_reason & ~0xffff) ? " " : "", \
(isa == KVM_ISA_VMX) ? \
__print_flags(exit_reason & ~0xffff, " ", VMX_EXIT_REASON_FLAGS) : ""
--
2.19.1.6.gb485710b