KVM: x86: Unify pr_fmt to use module name for all KVM modules

Define pr_fmt using KBUILD_MODNAME for all KVM x86 code so that printks
use consistent formatting across common x86, Intel, and AMD code.  In
addition to providing consistent print formatting, using KBUILD_MODNAME,
e.g. kvm_amd and kvm_intel, allows referencing SVM and VMX (and SEV and
SGX and ...) as technologies without generating weird messages, and
without causing naming conflicts with other kernel code, e.g. "SEV: ",
"tdx: ", "sgx: " etc.. are all used by the kernel for non-KVM subsystems.

Opportunistically move away from printk() for prints that need to be
modified anyways, e.g. to drop a manual "kvm: " prefix.

Opportunistically convert a few SGX WARNs that are similarly modified to
WARN_ONCE; in the very unlikely event that the WARNs fire, odds are good
that they would fire repeatedly and spam the kernel log without providing
unique information in each print.

Note, defining pr_fmt yields undesirable results for code that uses KVM's
printk wrappers, e.g. vcpu_unimpl().  But, that's a pre-existing problem
as SVM/kvm_amd already defines a pr_fmt, and thankfully use of KVM's
wrappers is relatively limited in KVM x86 code.

Signed-off-by: Sean Christopherson <seanjc@google.com>
Reviewed-by: Paul Durrant <paul@xen.org>
Message-Id: <20221130230934.1014142-35-seanjc@google.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>

7 files changed, 13 insertions, 9 deletions

diff --git a/arch/x86/kvm/svm/avic.c b/arch/x86/kvm/svm/avic.c
index 6919dee69f18..f52f5e0dd465 100644
--- a/arch/x86/kvm/svm/avic.c
+++ b/arch/x86/kvm/svm/avic.c
@@ -12,7 +12,7 @@
  *   Avi Kivity   <avi@qumranet.com>
  */
 
-#define pr_fmt(fmt) "SVM: " fmt
+#define pr_fmt(fmt) KBUILD_MODNAME ": " fmt
 
 #include <linux/kvm_types.h>
 #include <linux/hashtable.h>
diff --git a/arch/x86/kvm/svm/nested.c b/arch/x86/kvm/svm/nested.c
index bc9cd7086fa9..3bfbcb607d80 100644
--- a/arch/x86/kvm/svm/nested.c
+++ b/arch/x86/kvm/svm/nested.c
@@ -12,7 +12,7 @@
  *   Avi Kivity   <avi@qumranet.com>
  */
 
-#define pr_fmt(fmt) "SVM: " fmt
+#define pr_fmt(fmt) KBUILD_MODNAME ": " fmt
 
 #include <linux/kvm_types.h>
 #include <linux/kvm_host.h>
diff --git a/arch/x86/kvm/svm/pmu.c b/arch/x86/kvm/svm/pmu.c
index 0e313fbae055..1ff068f23841 100644
--- a/arch/x86/kvm/svm/pmu.c
+++ b/arch/x86/kvm/svm/pmu.c
@@ -9,6 +9,8 @@
  *
  * Implementation is based on pmu_intel.c file
  */
+#define pr_fmt(fmt) KBUILD_MODNAME ": " fmt
+
 #include <linux/types.h>
 #include <linux/kvm_host.h>
 #include <linux/perf_event.h>
diff --git a/arch/x86/kvm/svm/sev.c b/arch/x86/kvm/svm/sev.c
index 86d6897f4806..273cba809328 100644
--- a/arch/x86/kvm/svm/sev.c
+++ b/arch/x86/kvm/svm/sev.c
@@ -6,6 +6,7 @@
  *
  * Copyright 2010 Red Hat, Inc. and/or its affiliates.
  */
+#define pr_fmt(fmt) KBUILD_MODNAME ": " fmt
 
 #include <linux/kvm_types.h>
 #include <linux/kvm_host.h>
diff --git a/arch/x86/kvm/svm/svm.c b/arch/x86/kvm/svm/svm.c
index 2bb62c3db3b3..f7192a14fc89 100644
--- a/arch/x86/kvm/svm/svm.c
+++ b/arch/x86/kvm/svm/svm.c
@@ -1,4 +1,4 @@
-#define pr_fmt(fmt) "SVM: " fmt
+#define pr_fmt(fmt) KBUILD_MODNAME ": " fmt
 
 #include <linux/kvm_host.h>
 
@@ -2076,7 +2076,7 @@ static void svm_handle_mce(struct kvm_vcpu *vcpu)
 		 * Erratum 383 triggered. Guest state is corrupt so kill the
 		 * guest.
 		 */
-		pr_err("KVM: Guest triggered AMD Erratum 383\n");
+		pr_err("Guest triggered AMD Erratum 383\n");
 
 		kvm_make_request(KVM_REQ_TRIPLE_FAULT, vcpu);
 
@@ -4629,7 +4629,7 @@ static bool svm_can_emulate_instruction(struct kvm_vcpu *vcpu, int emul_type,
 	smap = cr4 & X86_CR4_SMAP;
 	is_user = svm_get_cpl(vcpu) == 3;
 	if (smap && (!smep || is_user)) {
-		pr_err_ratelimited("KVM: SEV Guest triggered AMD Erratum 1096\n");
+		pr_err_ratelimited("SEV Guest triggered AMD Erratum 1096\n");
 
 		/*
 		 * If the fault occurred in userspace, arbitrarily inject #GP
@@ -4978,7 +4978,7 @@ static __init int svm_hardware_setup(void)
 	}
 
 	if (nested) {
-		printk(KERN_INFO "kvm: Nested Virtualization enabled\n");
+		pr_info("Nested Virtualization enabled\n");
 		kvm_enable_efer_bits(EFER_SVME | EFER_LMSLE);
 	}
 
@@ -4996,7 +4996,7 @@ static __init int svm_hardware_setup(void)
 	/* Force VM NPT level equal to the host's paging level */
 	kvm_configure_mmu(npt_enabled, get_npt_level(),
 			  get_npt_level(), PG_LEVEL_1G);
-	pr_info("kvm: Nested Paging %sabled\n", npt_enabled ? "en" : "dis");
+	pr_info("Nested Paging %sabled\n", npt_enabled ? "en" : "dis");
 
 	/* Setup shadow_me_value and shadow_me_mask */
 	kvm_mmu_set_me_spte_mask(sme_me_mask, sme_me_mask);
diff --git a/arch/x86/kvm/svm/svm_onhyperv.c b/arch/x86/kvm/svm/svm_onhyperv.c
index 26a89d0da93e..7af8422d3382 100644
--- a/arch/x86/kvm/svm/svm_onhyperv.c
+++ b/arch/x86/kvm/svm/svm_onhyperv.c
@@ -2,6 +2,7 @@
 /*
  * KVM L1 hypervisor optimizations on Hyper-V for SVM.
  */
+#define pr_fmt(fmt) KBUILD_MODNAME ": " fmt
 
 #include <linux/kvm_host.h>
 
diff --git a/arch/x86/kvm/svm/svm_onhyperv.h b/arch/x86/kvm/svm/svm_onhyperv.h
index 45faf84476ce..6981c1e9a809 100644
--- a/arch/x86/kvm/svm/svm_onhyperv.h
+++ b/arch/x86/kvm/svm/svm_onhyperv.h
@@ -34,7 +34,7 @@ static inline void svm_hv_hardware_setup(void)
 {
 	if (npt_enabled &&
 	    ms_hyperv.nested_features & HV_X64_NESTED_ENLIGHTENED_TLB) {
-		pr_info("kvm: Hyper-V enlightened NPT TLB flush enabled\n");
+		pr_info(KBUILD_MODNAME ": Hyper-V enlightened NPT TLB flush enabled\n");
 		svm_x86_ops.tlb_remote_flush = hv_remote_flush_tlb;
 		svm_x86_ops.tlb_remote_flush_with_range =
 				hv_remote_flush_tlb_with_range;
@@ -43,7 +43,7 @@ static inline void svm_hv_hardware_setup(void)
 	if (ms_hyperv.nested_features & HV_X64_NESTED_DIRECT_FLUSH) {
 		int cpu;
 
-		pr_info("kvm: Hyper-V Direct TLB Flush enabled\n");
+		pr_info(KBUILD_MODNAME ": Hyper-V Direct TLB Flush enabled\n");
 		for_each_online_cpu(cpu) {
 			struct hv_vp_assist_page *vp_ap =
 				hv_get_vp_assist_page(cpu);