[RFC PATCH v6 018/104] KVM: TDX: Add helper functions to print TDX SEAMCALL error

[isaku.yamahata@intel.com]

From: Isaku Yamahata <isaku.yamahata@intel.com>

Add helper functions to print out errors from the TDX module in a uniform
manner.

Signed-off-by: Isaku Yamahata <isaku.yamahata@intel.com>
---
 arch/x86/kvm/Makefile        |  2 +-
 arch/x86/kvm/vmx/tdx_error.c | 22 ++++++++++++++++++++++
 arch/x86/kvm/vmx/tdx_ops.h   |  3 +++
 3 files changed, 26 insertions(+), 1 deletion(-)
 create mode 100644 arch/x86/kvm/vmx/tdx_error.c

diff --git a/arch/x86/kvm/Makefile b/arch/x86/kvm/Makefile
index e2c05195cb95..f1ad445df505 100644
--- a/arch/x86/kvm/Makefile
+++ b/arch/x86/kvm/Makefile
@@ -24,7 +24,7 @@ kvm-$(CONFIG_KVM_XEN)	+= xen.o
 kvm-intel-y		+= vmx/vmx.o vmx/vmenter.o vmx/pmu_intel.o vmx/vmcs12.o \
 			   vmx/evmcs.o vmx/nested.o vmx/posted_intr.o vmx/main.o
 kvm-intel-$(CONFIG_X86_SGX_KVM)	+= vmx/sgx.o
-kvm-intel-$(CONFIG_INTEL_TDX_HOST)	+= vmx/tdx.o
+kvm-intel-$(CONFIG_INTEL_TDX_HOST)	+= vmx/tdx.o vmx/tdx_error.o
 
 kvm-amd-y		+= svm/svm.o svm/vmenter.o svm/pmu.o svm/nested.o svm/avic.o svm/sev.o
 
diff --git a/arch/x86/kvm/vmx/tdx_error.c b/arch/x86/kvm/vmx/tdx_error.c
new file mode 100644
index 000000000000..61ed855d1188
--- /dev/null
+++ b/arch/x86/kvm/vmx/tdx_error.c
@@ -0,0 +1,22 @@
+// SPDX-License-Identifier: GPL-2.0
+/* functions to record TDX SEAMCALL error */
+
+#include <linux/kernel.h>
+#include <linux/bug.h>
+
+#include "tdx_ops.h"
+
+void pr_tdx_error(u64 op, u64 error_code, const struct tdx_module_output *out)
+{
+	if (!out) {
+		pr_err_ratelimited("SEAMCALL[%lld] failed: 0x%llx\n",
+				op, error_code);
+		return;
+	}
+
+	pr_err_ratelimited(
+		"SEAMCALL[%lld] failed: 0x%llx "
+		"RCX 0x%llx, RDX 0x%llx, R8 0x%llx, R9 0x%llx, R10 0x%llx, R11 0x%llx\n",
+		op, error_code,
+		out->rcx, out->rdx, out->r8, out->r9, out->r10, out->r11);
+}
diff --git a/arch/x86/kvm/vmx/tdx_ops.h b/arch/x86/kvm/vmx/tdx_ops.h
index 85adbf49c277..8cc2f01c509b 100644
--- a/arch/x86/kvm/vmx/tdx_ops.h
+++ b/arch/x86/kvm/vmx/tdx_ops.h
@@ -9,12 +9,15 @@
 #include <asm/cacheflush.h>
 #include <asm/asm.h>
 #include <asm/kvm_host.h>
+#include <asm/tdx.h>
 
 #include "tdx_errno.h"
 #include "tdx_arch.h"
 
 #ifdef CONFIG_INTEL_TDX_HOST
 
+void pr_tdx_error(u64 op, u64 error_code, const struct tdx_module_output *out);
+
 static inline u64 tdh_mng_addcx(hpa_t tdr, hpa_t addr)
 {
 	clflush_cache_range(__va(addr), PAGE_SIZE);
-- 
2.25.1