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The use of this module poses a security risk in > any trusted execution environment and is generally discouraged. > > Instead, provide an file in SYSFS in the /sys/hypervisor/sev/ > directory to provide the value of the SEV_STATUS MSR to user-space. > > Signed-off-by: Joerg Roedel > --- > Documentation/ABI/testing/sysfs-hypervisor | 5 +++++ > arch/x86/coco/sev/core.c | 9 +++++++++ > 2 files changed, 14 insertions(+) > > diff --git a/Documentation/ABI/testing/sysfs-hypervisor b/Documentation/ABI/testing/sysfs-hypervisor > index aca8b02c878c..54c80899c19c 100644 > --- a/Documentation/ABI/testing/sysfs-hypervisor > +++ b/Documentation/ABI/testing/sysfs-hypervisor > @@ -1,5 +1,6 @@ > What: /sys/devices/system/cpu/sev > /sys/devices/system/cpu/sev/vmpl > + /sys/devices/system/cpu/sev/sev_status > Date: May 2024 > Contact: Linux kernel mailing list > Description: Secure Encrypted Virtualization (SEV) information > @@ -8,3 +9,7 @@ Description: Secure Encrypted Virtualization (SEV) information > > vmpl: Reports the Virtual Machine Privilege Level (VMPL) at which > the SEV-SNP guest is running. > + > + sev_status: Reports the value of the SEV_STATUS MSR which > + enumerates the enabled features of an SEV-SNP > + environment. > diff --git a/arch/x86/coco/sev/core.c b/arch/x86/coco/sev/core.c > index 51a04a19449b..3e834ce9badc 100644 > --- a/arch/x86/coco/sev/core.c > +++ b/arch/x86/coco/sev/core.c > @@ -2678,10 +2678,19 @@ static ssize_t vmpl_show(struct kobject *kobj, > return sysfs_emit(buf, "%d\n", snp_vmpl); > } > > +static ssize_t sev_status_show(struct kobject *kobj, > + struct kobj_attribute *attr, char *buf) > +{ > + return sysfs_emit(buf, "%llx\n", sev_status); Should it be prefixed with '0x'? That would make use of functions like atoi() and strtol() easier. Thanks, Tom > +} > + > static struct kobj_attribute vmpl_attr = __ATTR_RO(vmpl); > +static struct kobj_attribute sev_status_attr = __ATTR_RO(sev_status); > + > > static struct attribute *vmpl_attrs[] = { > &vmpl_attr.attr, > + &sev_status_attr.attr, > NULL > }; >