2022-05-18 10:12:52

by Steffen Eiden

Subject: [PATCH] s390: Add attestation query information

We have information about the supported attestation header version
and paf (= plaintext attestation flag) bits.
Let's expose it via the sysfs files.

Signed-off-by: Steffen Eiden <[email protected]>
---
arch/s390/boot/uv.c | 2 ++
arch/s390/include/asm/uv.h | 7 ++++++-
arch/s390/kernel/uv.c | 20 ++++++++++++++++++++
3 files changed, 28 insertions(+), 1 deletion(-)

diff --git a/arch/s390/boot/uv.c b/arch/s390/boot/uv.c
index e6be155ab2e5..5e17c657e3d6 100644
--- a/arch/s390/boot/uv.c
+++ b/arch/s390/boot/uv.c
@@ -41,6 +41,8 @@ void uv_query_info(void)
uv_info.max_num_sec_conf = uvcb.max_num_sec_conf;
uv_info.max_guest_cpu_id = uvcb.max_guest_cpu_id;
uv_info.uv_feature_indications = uvcb.uv_feature_indications;
+ uv_info.supp_att_req_hdr_ver = uvcb.supp_att_req_hdr_ver;
+ uv_info.supp_att_pflags = uvcb.supp_att_pflags;
}

#ifdef CONFIG_PROTECTED_VIRTUALIZATION_GUEST
diff --git a/arch/s390/include/asm/uv.h b/arch/s390/include/asm/uv.h
index cfea7b77a5b8..99f459c0eacc 100644
--- a/arch/s390/include/asm/uv.h
+++ b/arch/s390/include/asm/uv.h
@@ -110,7 +110,10 @@ struct uv_cb_qui {
u8 reserved88[158 - 136]; /* 0x0088 */
u16 max_guest_cpu_id; /* 0x009e */
u64 uv_feature_indications; /* 0x00a0 */
- u8 reserveda8[200 - 168]; /* 0x00a8 */
+ u8 reserveda8[224 - 168]; /* 0x00a8 */
+ u64 supp_att_req_hdr_ver; /* 0x00e0 */
+ u64 supp_att_pflags; /* 0x00e8 */
+ u8 reservedf0[256 - 240]; /* 0x00f0 */
} __packed __aligned(8);

/* Initialize Ultravisor */
@@ -307,6 +310,8 @@ struct uv_info {
unsigned int max_num_sec_conf;
unsigned short max_guest_cpu_id;
unsigned long uv_feature_indications;
+ unsigned long supp_att_req_hdr_ver;
+ unsigned long supp_att_pflags;
};

extern struct uv_info uv_info;
diff --git a/arch/s390/kernel/uv.c b/arch/s390/kernel/uv.c
index a5425075dd25..095afd375ad1 100644
--- a/arch/s390/kernel/uv.c
+++ b/arch/s390/kernel/uv.c
@@ -431,12 +431,32 @@ static ssize_t uv_query_max_guest_addr(struct kobject *kobj,
static struct kobj_attribute uv_query_max_guest_addr_attr =
__ATTR(max_address, 0444, uv_query_max_guest_addr, NULL);

+static ssize_t uv_query_supp_att_req_hdr_ver(struct kobject *kobj,
+ struct kobj_attribute *attr, char *page)
+{
+ return scnprintf(page, PAGE_SIZE, "%lx\n", uv_info.supp_att_req_hdr_ver);
+}
+
+static struct kobj_attribute uv_query_supp_att_req_hdr_ver_attr =
+ __ATTR(supp_att_req_hdr_ver, 0444, uv_query_supp_att_req_hdr_ver, NULL);
+
+static ssize_t uv_query_supp_att_pflags(struct kobject *kobj,
+ struct kobj_attribute *attr, char *page)
+{
+ return scnprintf(page, PAGE_SIZE, "%lx\n", uv_info.supp_att_pflags);
+}
+
+static struct kobj_attribute uv_query_supp_att_pflags_attr =
+ __ATTR(supp_att_pflags, 0444, uv_query_supp_att_pflags, NULL);
+
static struct attribute *uv_query_attrs[] = {
&uv_query_facilities_attr.attr,
&uv_query_feature_indications_attr.attr,
&uv_query_max_guest_cpus_attr.attr,
&uv_query_max_guest_vms_attr.attr,
&uv_query_max_guest_addr_attr.attr,
+ &uv_query_supp_att_req_hdr_ver_attr.attr,
+ &uv_query_supp_att_pflags_attr.attr,
NULL,
};

--
2.30.2

2022-05-18 11:58:35

by Heiko Carstens

Subject: Re: [PATCH] s390: Add attestation query information

On Wed, May 18, 2022 at 09:51:13AM +0000, Steffen Eiden wrote:
> We have information about the supported attestation header version
> and paf (= plaintext attestation flag) bits.
> Let's expose it via the sysfs files.
>
> Signed-off-by: Steffen Eiden <[email protected]>
> ---
> arch/s390/boot/uv.c | 2 ++
> arch/s390/include/asm/uv.h | 7 ++++++-
> arch/s390/kernel/uv.c | 20 ++++++++++++++++++++
> 3 files changed, 28 insertions(+), 1 deletion(-)

Please write in the cover-letter *why* this is needed.