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-rw-r--r--Documentation/ABI/testing/securityfs-secrets-coco51
-rw-r--r--Documentation/ABI/testing/sysfs-class-firmware-attributes48
-rw-r--r--Documentation/ABI/testing/sysfs-driver-intel_sdsi18
-rw-r--r--Documentation/ABI/testing/sysfs-fs-erofs5
4 files changed, 90 insertions, 32 deletions
diff --git a/Documentation/ABI/testing/securityfs-secrets-coco b/Documentation/ABI/testing/securityfs-secrets-coco
new file mode 100644
index 000000000000..f2b6909155f9
--- /dev/null
+++ b/Documentation/ABI/testing/securityfs-secrets-coco
@@ -0,0 +1,51 @@
+What: security/secrets/coco
+Date: February 2022
+Contact: Dov Murik <[email protected]>
+Description:
+ Exposes confidential computing (coco) EFI secrets to
+ userspace via securityfs.
+
+ EFI can declare memory area used by confidential computing
+ platforms (such as AMD SEV and SEV-ES) for secret injection by
+ the Guest Owner during VM's launch. The secrets are encrypted
+ by the Guest Owner and decrypted inside the trusted enclave,
+ and therefore are not readable by the untrusted host.
+
+ The efi_secret module exposes the secrets to userspace. Each
+ secret appears as a file under <securityfs>/secrets/coco,
+ where the filename is the GUID of the entry in the secrets
+ table. This module is loaded automatically by the EFI driver
+ if the EFI secret area is populated.
+
+ Two operations are supported for the files: read and unlink.
+ Reading the file returns the content of secret entry.
+ Unlinking the file overwrites the secret data with zeroes and
+ removes the entry from the filesystem. A secret cannot be read
+ after it has been unlinked.
+
+ For example, listing the available secrets::
+
+ # modprobe efi_secret
+ # ls -l /sys/kernel/security/secrets/coco
+ -r--r----- 1 root root 0 Jun 28 11:54 736870e5-84f0-4973-92ec-06879ce3da0b
+ -r--r----- 1 root root 0 Jun 28 11:54 83c83f7f-1356-4975-8b7e-d3a0b54312c6
+ -r--r----- 1 root root 0 Jun 28 11:54 9553f55d-3da2-43ee-ab5d-ff17f78864d2
+ -r--r----- 1 root root 0 Jun 28 11:54 e6f5a162-d67f-4750-a67c-5d065f2a9910
+
+ Reading the secret data by reading a file::
+
+ # cat /sys/kernel/security/secrets/coco/e6f5a162-d67f-4750-a67c-5d065f2a9910
+ the-content-of-the-secret-data
+
+ Wiping a secret by unlinking a file::
+
+ # rm /sys/kernel/security/secrets/coco/e6f5a162-d67f-4750-a67c-5d065f2a9910
+ # ls -l /sys/kernel/security/secrets/coco
+ -r--r----- 1 root root 0 Jun 28 11:54 736870e5-84f0-4973-92ec-06879ce3da0b
+ -r--r----- 1 root root 0 Jun 28 11:54 83c83f7f-1356-4975-8b7e-d3a0b54312c6
+ -r--r----- 1 root root 0 Jun 28 11:54 9553f55d-3da2-43ee-ab5d-ff17f78864d2
+
+ Note: The binary format of the secrets table injected by the
+ Guest Owner is described in
+ drivers/virt/coco/efi_secret/efi_secret.c under "Structure of
+ the EFI secret area".
diff --git a/Documentation/ABI/testing/sysfs-class-firmware-attributes b/Documentation/ABI/testing/sysfs-class-firmware-attributes
index 05820365f1ec..4cdba3477176 100644
--- a/Documentation/ABI/testing/sysfs-class-firmware-attributes
+++ b/Documentation/ABI/testing/sysfs-class-firmware-attributes
@@ -116,7 +116,7 @@ Description:
<value>[ForceIf:<attribute>=<value>]
<value>[ForceIfNot:<attribute>=<value>]
- For example:
+ For example::
LegacyOrom/dell_value_modifier has value:
Disabled[ForceIf:SecureBoot=Enabled]
@@ -212,7 +212,7 @@ Description:
the next boot.
Lenovo specific class extensions
- ------------------------------
+ --------------------------------
On Lenovo systems the following additional settings are available:
@@ -246,9 +246,7 @@ Description:
that is being referenced (e.g hdd0, hdd1 etc)
This attribute defaults to device 0.
- certificate:
- signature:
- save_signature:
+ certificate, signature, save_signature:
These attributes are used for certificate based authentication. This is
used in conjunction with a signing server as an alternative to password
based authentication.
@@ -257,22 +255,27 @@ Description:
The attributes can be displayed to check the stored value.
Some usage examples:
- Installing a certificate to enable feature:
- echo <supervisor password > authentication/Admin/current_password
- echo <signed certificate> > authentication/Admin/certificate
- Updating the installed certificate:
- echo <signature> > authentication/Admin/signature
- echo <signed certificate> > authentication/Admin/certificate
+ Installing a certificate to enable feature::
+
+ echo "supervisor password" > authentication/Admin/current_password
+ echo "signed certificate" > authentication/Admin/certificate
+
+ Updating the installed certificate::
+
+ echo "signature" > authentication/Admin/signature
+ echo "signed certificate" > authentication/Admin/certificate
- Removing the installed certificate:
- echo <signature> > authentication/Admin/signature
- echo '' > authentication/Admin/certificate
+ Removing the installed certificate::
- Changing a BIOS setting:
- echo <signature> > authentication/Admin/signature
- echo <save signature> > authentication/Admin/save_signature
- echo Enable > attribute/PasswordBeep/current_value
+ echo "signature" > authentication/Admin/signature
+ echo "" > authentication/Admin/certificate
+
+ Changing a BIOS setting::
+
+ echo "signature" > authentication/Admin/signature
+ echo "save signature" > authentication/Admin/save_signature
+ echo Enable > attribute/PasswordBeep/current_value
You cannot enable certificate authentication if a supervisor password
has not been set.
@@ -288,9 +291,10 @@ Description:
certificate_to_password:
Write only attribute used to switch from certificate based authentication
back to password based.
- Usage:
- echo <signature> > authentication/Admin/signature
- echo <password> > authentication/Admin/certificate_to_password
+ Usage::
+
+ echo "signature" > authentication/Admin/signature
+ echo "password" > authentication/Admin/certificate_to_password
What: /sys/class/firmware-attributes/*/attributes/pending_reboot
@@ -345,7 +349,7 @@ Description:
# echo "factory" > /sys/class/firmware-attributes/*/device/attributes/reset_bios
# cat /sys/class/firmware-attributes/*/device/attributes/reset_bios
- # builtinsafe lastknowngood [factory] custom
+ builtinsafe lastknowngood [factory] custom
Note that any changes to this attribute requires a reboot
for changes to take effect.
diff --git a/Documentation/ABI/testing/sysfs-driver-intel_sdsi b/Documentation/ABI/testing/sysfs-driver-intel_sdsi
index ab122125ff9a..96b92c105ec4 100644
--- a/Documentation/ABI/testing/sysfs-driver-intel_sdsi
+++ b/Documentation/ABI/testing/sysfs-driver-intel_sdsi
@@ -13,17 +13,19 @@ Description:
Should the operation fail, one of the following error codes
may be returned:
+ ========== =====
Error Code Cause
- ---------- -----
- EIO General mailbox failure. Log may indicate cause.
- EBUSY Mailbox is owned by another agent.
- EPERM SDSI capability is not enabled in hardware.
- EPROTO Failure in mailbox protocol detected by driver.
+ ========== =====
+ EIO General mailbox failure. Log may indicate cause.
+ EBUSY Mailbox is owned by another agent.
+ EPERM SDSI capability is not enabled in hardware.
+ EPROTO Failure in mailbox protocol detected by driver.
See log for details.
- EOVERFLOW For provision commands, the size of the data
+ EOVERFLOW For provision commands, the size of the data
exceeds what may be written.
- ESPIPE Seeking is not allowed.
- ETIMEDOUT Failure to complete mailbox transaction in time.
+ ESPIPE Seeking is not allowed.
+ ETIMEDOUT Failure to complete mailbox transaction in time.
+ ========== =====
What: /sys/bus/auxiliary/devices/intel_vsec.sdsi.X/guid
Date: Feb 2022
diff --git a/Documentation/ABI/testing/sysfs-fs-erofs b/Documentation/ABI/testing/sysfs-fs-erofs
index 05482374a741..bb4681a01811 100644
--- a/Documentation/ABI/testing/sysfs-fs-erofs
+++ b/Documentation/ABI/testing/sysfs-fs-erofs
@@ -9,8 +9,9 @@ Description: Shows all enabled kernel features.
What: /sys/fs/erofs/<disk>/sync_decompress
Date: November 2021
Contact: "Huang Jianan" <[email protected]>
-Description: Control strategy of sync decompression
+Description: Control strategy of sync decompression:
+
- 0 (default, auto): enable for readpage, and enable for
- readahead on atomic contexts only,
+ readahead on atomic contexts only.
- 1 (force on): enable for readpage and readahead.
- 2 (force off): disable for all situations.