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>> + >> + if (!sysinfo) >> + return 0; >> + >> + return tdx_supports_runtime_update(sysinfo) ? attr->mode : 0; >> +} >> + >> +static const struct attribute_group seamldr_group = { >> + .attrs = seamldr_attrs, >> + .is_visible = seamldr_group_visible, >> +}; > >I feel like we need to mention *somewhere* that these are kinda nasty. >tdx_get_sysinfo() is slow and single-threaded. These very much are and >need to stay 0400 for good reason. > >Talk about the DEVICE_ATTR_ADMIN_RO() choice _somewhere_, please. I will add a comment to make the DEVICE_ATTR_ADMIN_RO() choice explicit. +/* + * These attributes are intended for admins managing TDX module updates. + * Reading them issues a slow, serialized P-SEAMLDR query, so keep them + * admin-only. + */ static DEVICE_ATTR_ADMIN_RO(seamldr_version); static DEVICE_ATTR_ADMIN_RO(num_remaining_updates);