Re: [PATCH v2 5/7] tools: secure guest check for AMD in virt-host-validate

From: Boris Fiuczynski <fiuczy(a)linux.ibm.com&gt; Add checking in virt-host-validate for secure guest support on x86 for AMD Secure Encrypted Virtualization. Signed-off-by: Boris Fiuczynski <fiuczy(a)linux.ibm.com&gt; Reviewed-by: Paulo de Rezende Pinatti <ppinatti(a)linux.ibm.com&gt; Reviewed-by: Bjoern Walk <bwalk(a)linux.ibm.com&gt; --- tools/virt-host-validate-common.c | 29 +++++++++++++++++++++++++++-- tools/virt-host-validate-common.h | 1 + 2 files changed, 28 insertions(+), 2 deletions(-) diff --git a/tools/virt-host-validate-common.c b/tools/virt-host-validate-common.c index 8ead68798f..de007f2c43 100644 --- a/tools/virt-host-validate-common.c +++ b/tools/virt-host-validate-common.c @@ -41,7 +41,8 @@ VIR_ENUM_IMPL(virHostValidateCPUFlag, "vmx", "svm", "sie", - "158"); + "158", + "sev"); static bool quiet; @@ -447,15 +448,18 @@ int virHostValidateSecureGuests(const char *hvname, virHostValidateLevel level) { virBitmapPtr flags; - bool hasFac158 = false; + bool hasFac158 = false, hasAMDSev = false;

virArch arch = virArchFromHost(); g_autofree char *cmdline = NULL; static const char *kIBMValues[] = {"y", "Y", "on", "ON", "oN", "On", "1"}; + g_autofree char *mod_value = NULL; flags = virHostValidateGetCPUFlags(); if (flags && virBitmapIsBitSet(flags, VIR_HOST_VALIDATE_CPU_FLAG_FACILITY_158)) hasFac158 = true; + else if (flags && virBitmapIsBitSet(flags, VIR_HOST_VALIDATE_CPU_FLAG_SEV)) + hasAMDSev = true; virBitmapFree(flags); @@ -485,6 +489,27 @@ int virHostValidateSecureGuests(const char *hvname, virHostMsgFail(level, "Hardware or firmware does not provide " "support for IBM Secure Execution"); } + } else if (hasAMDSev) { + if (virFileReadValueString(&mod_value, "/sys/module/kvm_amd/parameters/sev") < 0) { + virHostMsgFail(level, "AMD Secure Encrypted Virtualization not " + "supported by the currently used kernel"); + return 0; + }

+ if (mod_value[0] != '1') { + virHostMsgFail(level, + "AMD Secure Encrypted Virtualization appears to be " + "disabled in kernel. Add mem_encrypt=on " + "kvm_amd.sev=1 to kernel cmdline arguments"); + return 0; + }