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-rw-r--r--Documentation/ABI/testing/sysfs-devices-system-cpu1
-rw-r--r--Documentation/admin-guide/hw-vuln/index.rst1
-rw-r--r--Documentation/admin-guide/hw-vuln/reg-file-data-sampling.rst104
-rw-r--r--Documentation/admin-guide/kernel-parameters.txt25
-rw-r--r--Documentation/arch/x86/amd-memory-encryption.rst16
-rw-r--r--Documentation/conf.py6
-rw-r--r--Documentation/devicetree/bindings/display/msm/qcom,mdss.yaml1
-rw-r--r--Documentation/netlink/specs/devlink.yaml2
-rw-r--r--Documentation/netlink/specs/dpll.yaml1
-rw-r--r--Documentation/userspace-api/media/mediactl/media-types.rst11
10 files changed, 147 insertions, 21 deletions
diff --git a/Documentation/ABI/testing/sysfs-devices-system-cpu b/Documentation/ABI/testing/sysfs-devices-system-cpu
index a1db6db475..710d47be11 100644
--- a/Documentation/ABI/testing/sysfs-devices-system-cpu
+++ b/Documentation/ABI/testing/sysfs-devices-system-cpu
@@ -516,6 +516,7 @@ What: /sys/devices/system/cpu/vulnerabilities
/sys/devices/system/cpu/vulnerabilities/mds
/sys/devices/system/cpu/vulnerabilities/meltdown
/sys/devices/system/cpu/vulnerabilities/mmio_stale_data
+ /sys/devices/system/cpu/vulnerabilities/reg_file_data_sampling
/sys/devices/system/cpu/vulnerabilities/retbleed
/sys/devices/system/cpu/vulnerabilities/spec_store_bypass
/sys/devices/system/cpu/vulnerabilities/spectre_v1
diff --git a/Documentation/admin-guide/hw-vuln/index.rst b/Documentation/admin-guide/hw-vuln/index.rst
index de99caabf6..ff0b440ef2 100644
--- a/Documentation/admin-guide/hw-vuln/index.rst
+++ b/Documentation/admin-guide/hw-vuln/index.rst
@@ -21,3 +21,4 @@ are configurable at compile, boot or run time.
cross-thread-rsb
srso
gather_data_sampling
+ reg-file-data-sampling
diff --git a/Documentation/admin-guide/hw-vuln/reg-file-data-sampling.rst b/Documentation/admin-guide/hw-vuln/reg-file-data-sampling.rst
new file mode 100644
index 0000000000..0585d02b9a
--- /dev/null
+++ b/Documentation/admin-guide/hw-vuln/reg-file-data-sampling.rst
@@ -0,0 +1,104 @@
+==================================
+Register File Data Sampling (RFDS)
+==================================
+
+Register File Data Sampling (RFDS) is a microarchitectural vulnerability that
+only affects Intel Atom parts(also branded as E-cores). RFDS may allow
+a malicious actor to infer data values previously used in floating point
+registers, vector registers, or integer registers. RFDS does not provide the
+ability to choose which data is inferred. CVE-2023-28746 is assigned to RFDS.
+
+Affected Processors
+===================
+Below is the list of affected Intel processors [#f1]_:
+
+ =================== ============
+ Common name Family_Model
+ =================== ============
+ ATOM_GOLDMONT 06_5CH
+ ATOM_GOLDMONT_D 06_5FH
+ ATOM_GOLDMONT_PLUS 06_7AH
+ ATOM_TREMONT_D 06_86H
+ ATOM_TREMONT 06_96H
+ ALDERLAKE 06_97H
+ ALDERLAKE_L 06_9AH
+ ATOM_TREMONT_L 06_9CH
+ RAPTORLAKE 06_B7H
+ RAPTORLAKE_P 06_BAH
+ ATOM_GRACEMONT 06_BEH
+ RAPTORLAKE_S 06_BFH
+ =================== ============
+
+As an exception to this table, Intel Xeon E family parts ALDERLAKE(06_97H) and
+RAPTORLAKE(06_B7H) codenamed Catlow are not affected. They are reported as
+vulnerable in Linux because they share the same family/model with an affected
+part. Unlike their affected counterparts, they do not enumerate RFDS_CLEAR or
+CPUID.HYBRID. This information could be used to distinguish between the
+affected and unaffected parts, but it is deemed not worth adding complexity as
+the reporting is fixed automatically when these parts enumerate RFDS_NO.
+
+Mitigation
+==========
+Intel released a microcode update that enables software to clear sensitive
+information using the VERW instruction. Like MDS, RFDS deploys the same
+mitigation strategy to force the CPU to clear the affected buffers before an
+attacker can extract the secrets. This is achieved by using the otherwise
+unused and obsolete VERW instruction in combination with a microcode update.
+The microcode clears the affected CPU buffers when the VERW instruction is
+executed.
+
+Mitigation points
+-----------------
+VERW is executed by the kernel before returning to user space, and by KVM
+before VMentry. None of the affected cores support SMT, so VERW is not required
+at C-state transitions.
+
+New bits in IA32_ARCH_CAPABILITIES
+----------------------------------
+Newer processors and microcode update on existing affected processors added new
+bits to IA32_ARCH_CAPABILITIES MSR. These bits can be used to enumerate
+vulnerability and mitigation capability:
+
+- Bit 27 - RFDS_NO - When set, processor is not affected by RFDS.
+- Bit 28 - RFDS_CLEAR - When set, processor is affected by RFDS, and has the
+ microcode that clears the affected buffers on VERW execution.
+
+Mitigation control on the kernel command line
+---------------------------------------------
+The kernel command line allows to control RFDS mitigation at boot time with the
+parameter "reg_file_data_sampling=". The valid arguments are:
+
+ ========== =================================================================
+ on If the CPU is vulnerable, enable mitigation; CPU buffer clearing
+ on exit to userspace and before entering a VM.
+ off Disables mitigation.
+ ========== =================================================================
+
+Mitigation default is selected by CONFIG_MITIGATION_RFDS.
+
+Mitigation status information
+-----------------------------
+The Linux kernel provides a sysfs interface to enumerate the current
+vulnerability status of the system: whether the system is vulnerable, and
+which mitigations are active. The relevant sysfs file is:
+
+ /sys/devices/system/cpu/vulnerabilities/reg_file_data_sampling
+
+The possible values in this file are:
+
+ .. list-table::
+
+ * - 'Not affected'
+ - The processor is not vulnerable
+ * - 'Vulnerable'
+ - The processor is vulnerable, but no mitigation enabled
+ * - 'Vulnerable: No microcode'
+ - The processor is vulnerable but microcode is not updated.
+ * - 'Mitigation: Clear Register File'
+ - The processor is vulnerable and the CPU buffer clearing mitigation is
+ enabled.
+
+References
+----------
+.. [#f1] Affected Processors
+ https://www.intel.com/content/www/us/en/developer/topic-technology/software-security-guidance/processors-affected-consolidated-product-cpu-model.html
diff --git a/Documentation/admin-guide/kernel-parameters.txt b/Documentation/admin-guide/kernel-parameters.txt
index b72e2049c4..7120c4e169 100644
--- a/Documentation/admin-guide/kernel-parameters.txt
+++ b/Documentation/admin-guide/kernel-parameters.txt
@@ -1137,6 +1137,26 @@
The filter can be disabled or changed to another
driver later using sysfs.
+ reg_file_data_sampling=
+ [X86] Controls mitigation for Register File Data
+ Sampling (RFDS) vulnerability. RFDS is a CPU
+ vulnerability which may allow userspace to infer
+ kernel data values previously stored in floating point
+ registers, vector registers, or integer registers.
+ RFDS only affects Intel Atom processors.
+
+ on: Turns ON the mitigation.
+ off: Turns OFF the mitigation.
+
+ This parameter overrides the compile time default set
+ by CONFIG_MITIGATION_RFDS. Mitigation cannot be
+ disabled when other VERW based mitigations (like MDS)
+ are enabled. In order to disable RFDS mitigation all
+ VERW based mitigations need to be disabled.
+
+ For details see:
+ Documentation/admin-guide/hw-vuln/reg-file-data-sampling.rst
+
driver_async_probe= [KNL]
List of driver names to be probed asynchronously. *
matches with all driver names. If * is specified, the
@@ -3307,9 +3327,7 @@
mem_encrypt= [X86-64] AMD Secure Memory Encryption (SME) control
Valid arguments: on, off
- Default (depends on kernel configuration option):
- on (CONFIG_AMD_MEM_ENCRYPT_ACTIVE_BY_DEFAULT=y)
- off (CONFIG_AMD_MEM_ENCRYPT_ACTIVE_BY_DEFAULT=n)
+ Default: off
mem_encrypt=on: Activate SME
mem_encrypt=off: Do not activate SME
@@ -3385,6 +3403,7 @@
nospectre_bhb [ARM64]
nospectre_v1 [X86,PPC]
nospectre_v2 [X86,PPC,S390,ARM64]
+ reg_file_data_sampling=off [X86]
retbleed=off [X86]
spec_store_bypass_disable=off [X86,PPC]
spectre_v2_user=off [X86]
diff --git a/Documentation/arch/x86/amd-memory-encryption.rst b/Documentation/arch/x86/amd-memory-encryption.rst
index 07caa8fff8..414bc7402a 100644
--- a/Documentation/arch/x86/amd-memory-encryption.rst
+++ b/Documentation/arch/x86/amd-memory-encryption.rst
@@ -87,14 +87,14 @@ The state of SME in the Linux kernel can be documented as follows:
kernel is non-zero).
SME can also be enabled and activated in the BIOS. If SME is enabled and
-activated in the BIOS, then all memory accesses will be encrypted and it will
-not be necessary to activate the Linux memory encryption support. If the BIOS
-merely enables SME (sets bit 23 of the MSR_AMD64_SYSCFG), then Linux can activate
-memory encryption by default (CONFIG_AMD_MEM_ENCRYPT_ACTIVE_BY_DEFAULT=y) or
-by supplying mem_encrypt=on on the kernel command line. However, if BIOS does
-not enable SME, then Linux will not be able to activate memory encryption, even
-if configured to do so by default or the mem_encrypt=on command line parameter
-is specified.
+activated in the BIOS, then all memory accesses will be encrypted and it
+will not be necessary to activate the Linux memory encryption support.
+
+If the BIOS merely enables SME (sets bit 23 of the MSR_AMD64_SYSCFG),
+then memory encryption can be enabled by supplying mem_encrypt=on on the
+kernel command line. However, if BIOS does not enable SME, then Linux
+will not be able to activate memory encryption, even if configured to do
+so by default or the mem_encrypt=on command line parameter is specified.
Secure Nested Paging (SNP)
==========================
diff --git a/Documentation/conf.py b/Documentation/conf.py
index dfc19c915d..e385e24fe9 100644
--- a/Documentation/conf.py
+++ b/Documentation/conf.py
@@ -345,9 +345,9 @@ sys.stderr.write("Using %s theme\n" % html_theme)
html_static_path = ['sphinx-static']
# If true, Docutils "smart quotes" will be used to convert quotes and dashes
-# to typographically correct entities. This will convert "--" to "—",
-# which is not always what we want, so disable it.
-smartquotes = False
+# to typographically correct entities. However, conversion of "--" to "—"
+# is not always what we want, so enable only quotes.
+smartquotes_action = 'q'
# Custom sidebar templates, maps document names to template names.
# Note that the RTD theme ignores this
diff --git a/Documentation/devicetree/bindings/display/msm/qcom,mdss.yaml b/Documentation/devicetree/bindings/display/msm/qcom,mdss.yaml
index 0999ea07f4..e4576546bf 100644
--- a/Documentation/devicetree/bindings/display/msm/qcom,mdss.yaml
+++ b/Documentation/devicetree/bindings/display/msm/qcom,mdss.yaml
@@ -127,6 +127,7 @@ patternProperties:
- qcom,dsi-phy-20nm
- qcom,dsi-phy-28nm-8226
- qcom,dsi-phy-28nm-hpm
+ - qcom,dsi-phy-28nm-hpm-fam-b
- qcom,dsi-phy-28nm-lp
- qcom,hdmi-phy-8084
- qcom,hdmi-phy-8660
diff --git a/Documentation/netlink/specs/devlink.yaml b/Documentation/netlink/specs/devlink.yaml
index 572d83a414..42a9d77803 100644
--- a/Documentation/netlink/specs/devlink.yaml
+++ b/Documentation/netlink/specs/devlink.yaml
@@ -244,7 +244,7 @@ attribute-sets:
-
name: eswitch-inline-mode
- type: u16
+ type: u8
enum: eswitch-inline-mode
-
name: dpipe-tables
diff --git a/Documentation/netlink/specs/dpll.yaml b/Documentation/netlink/specs/dpll.yaml
index 2b4c4bcd83..5b25ad589e 100644
--- a/Documentation/netlink/specs/dpll.yaml
+++ b/Documentation/netlink/specs/dpll.yaml
@@ -274,6 +274,7 @@ attribute-sets:
-
name: capabilities
type: u32
+ enum: pin-capabilities
-
name: parent-device
type: nest
diff --git a/Documentation/userspace-api/media/mediactl/media-types.rst b/Documentation/userspace-api/media/mediactl/media-types.rst
index 0ffeece1e0..6332e83952 100644
--- a/Documentation/userspace-api/media/mediactl/media-types.rst
+++ b/Documentation/userspace-api/media/mediactl/media-types.rst
@@ -375,12 +375,11 @@ Types and flags used to represent the media graph elements
are origins of links.
* - ``MEDIA_PAD_FL_MUST_CONNECT``
- - If this flag is set and the pad is linked to any other pad, then
- at least one of those links must be enabled for the entity to be
- able to stream. There could be temporary reasons (e.g. device
- configuration dependent) for the pad to need enabled links even
- when this flag isn't set; the absence of the flag doesn't imply
- there is none.
+ - If this flag is set, then for this pad to be able to stream, it must
+ be connected by at least one enabled link. There could be temporary
+ reasons (e.g. device configuration dependent) for the pad to need
+ enabled links even when this flag isn't set; the absence of the flag
+ doesn't imply there is none.
One and only one of ``MEDIA_PAD_FL_SINK`` and ``MEDIA_PAD_FL_SOURCE``