Adding upstream version 6.1.82.upstream/6.1.82upstream

Signed-off-by: Daniel Baumann <daniel.baumann@progress-linux.org>

11 files changed, 201 insertions, 49 deletions

diff --git a/Documentation/ABI/testing/sysfs-class-net-queues b/Documentation/ABI/testing/sysfs-class-net-queues
index 978b76358..40d5aab84 100644
--- a/Documentation/ABI/testing/sysfs-class-net-queues
+++ b/Documentation/ABI/testing/sysfs-class-net-queues
@@ -1,4 +1,4 @@
-What:		/sys/class/<iface>/queues/rx-<queue>/rps_cpus
+What:		/sys/class/net/<iface>/queues/rx-<queue>/rps_cpus
 Date:		March 2010
 KernelVersion:	2.6.35
 Contact:	netdev@vger.kernel.org
@@ -8,7 +8,7 @@ Description:
 		network device queue. Possible values depend on the number
 		of available CPU(s) in the system.
 
-What:		/sys/class/<iface>/queues/rx-<queue>/rps_flow_cnt
+What:		/sys/class/net/<iface>/queues/rx-<queue>/rps_flow_cnt
 Date:		April 2010
 KernelVersion:	2.6.35
 Contact:	netdev@vger.kernel.org
@@ -16,7 +16,7 @@ Description:
 		Number of Receive Packet Steering flows being currently
 		processed by this particular network device receive queue.
 
-What:		/sys/class/<iface>/queues/tx-<queue>/tx_timeout
+What:		/sys/class/net/<iface>/queues/tx-<queue>/tx_timeout
 Date:		November 2011
 KernelVersion:	3.3
 Contact:	netdev@vger.kernel.org
@@ -24,7 +24,7 @@ Description:
 		Indicates the number of transmit timeout events seen by this
 		network interface transmit queue.
 
-What:		/sys/class/<iface>/queues/tx-<queue>/tx_maxrate
+What:		/sys/class/net/<iface>/queues/tx-<queue>/tx_maxrate
 Date:		March 2015
 KernelVersion:	4.1
 Contact:	netdev@vger.kernel.org
@@ -32,7 +32,7 @@ Description:
 		A Mbps max-rate set for the queue, a value of zero means disabled,
 		default is disabled.
 
-What:		/sys/class/<iface>/queues/tx-<queue>/xps_cpus
+What:		/sys/class/net/<iface>/queues/tx-<queue>/xps_cpus
 Date:		November 2010
 KernelVersion:	2.6.38
 Contact:	netdev@vger.kernel.org
@@ -42,7 +42,7 @@ Description:
 		network device transmit queue. Possible vaules depend on the
 		number of available CPU(s) in the system.
 
-What:		/sys/class/<iface>/queues/tx-<queue>/xps_rxqs
+What:		/sys/class/net/<iface>/queues/tx-<queue>/xps_rxqs
 Date:		June 2018
 KernelVersion:	4.18.0
 Contact:	netdev@vger.kernel.org
@@ -53,7 +53,7 @@ Description:
 		number of available receive queue(s) in the network device.
 		Default is disabled.
 
-What:		/sys/class/<iface>/queues/tx-<queue>/byte_queue_limits/hold_time
+What:		/sys/class/net/<iface>/queues/tx-<queue>/byte_queue_limits/hold_time
 Date:		November 2011
 KernelVersion:	3.3
 Contact:	netdev@vger.kernel.org
@@ -62,7 +62,7 @@ Description:
 		of this particular network device transmit queue.
 		Default value is 1000.
 
-What:		/sys/class/<iface>/queues/tx-<queue>/byte_queue_limits/inflight
+What:		/sys/class/net/<iface>/queues/tx-<queue>/byte_queue_limits/inflight
 Date:		November 2011
 KernelVersion:	3.3
 Contact:	netdev@vger.kernel.org
@@ -70,7 +70,7 @@ Description:
 		Indicates the number of bytes (objects) in flight on this
 		network device transmit queue.
 
-What:		/sys/class/<iface>/queues/tx-<queue>/byte_queue_limits/limit
+What:		/sys/class/net/<iface>/queues/tx-<queue>/byte_queue_limits/limit
 Date:		November 2011
 KernelVersion:	3.3
 Contact:	netdev@vger.kernel.org
@@ -79,7 +79,7 @@ Description:
 		on this network device transmit queue. This value is clamped
 		to be within the bounds defined by limit_max and limit_min.
 
-What:		/sys/class/<iface>/queues/tx-<queue>/byte_queue_limits/limit_max
+What:		/sys/class/net/<iface>/queues/tx-<queue>/byte_queue_limits/limit_max
 Date:		November 2011
 KernelVersion:	3.3
 Contact:	netdev@vger.kernel.org
@@ -88,7 +88,7 @@ Description:
 		queued on this network device transmit queue. See
 		include/linux/dynamic_queue_limits.h for the default value.
 
-What:		/sys/class/<iface>/queues/tx-<queue>/byte_queue_limits/limit_min
+What:		/sys/class/net/<iface>/queues/tx-<queue>/byte_queue_limits/limit_min
 Date:		November 2011
 KernelVersion:	3.3
 Contact:	netdev@vger.kernel.org
diff --git a/Documentation/ABI/testing/sysfs-class-net-statistics b/Documentation/ABI/testing/sysfs-class-net-statistics
index 55db27815..53e508c69 100644
--- a/Documentation/ABI/testing/sysfs-class-net-statistics
+++ b/Documentation/ABI/testing/sysfs-class-net-statistics
@@ -1,4 +1,4 @@
-What:		/sys/class/<iface>/statistics/collisions
+What:		/sys/class/net/<iface>/statistics/collisions
 Date:		April 2005
 KernelVersion:	2.6.12
 Contact:	netdev@vger.kernel.org
@@ -6,7 +6,7 @@ Description:
 		Indicates the number of collisions seen by this network device.
 		This value might not be relevant with all MAC layers.
 
-What:		/sys/class/<iface>/statistics/multicast
+What:		/sys/class/net/<iface>/statistics/multicast
 Date:		April 2005
 KernelVersion:	2.6.12
 Contact:	netdev@vger.kernel.org
@@ -14,7 +14,7 @@ Description:
 		Indicates the number of multicast packets received by this
 		network device.
 
-What:		/sys/class/<iface>/statistics/rx_bytes
+What:		/sys/class/net/<iface>/statistics/rx_bytes
 Date:		April 2005
 KernelVersion:	2.6.12
 Contact:	netdev@vger.kernel.org
@@ -23,7 +23,7 @@ Description:
 		See the network driver for the exact meaning of when this
 		value is incremented.
 
-What:		/sys/class/<iface>/statistics/rx_compressed
+What:		/sys/class/net/<iface>/statistics/rx_compressed
 Date:		April 2005
 KernelVersion:	2.6.12
 Contact:	netdev@vger.kernel.org
@@ -32,7 +32,7 @@ Description:
 		network device. This value might only be relevant for interfaces
 		that support packet compression (e.g: PPP).
 
-What:		/sys/class/<iface>/statistics/rx_crc_errors
+What:		/sys/class/net/<iface>/statistics/rx_crc_errors
 Date:		April 2005
 KernelVersion:	2.6.12
 Contact:	netdev@vger.kernel.org
@@ -41,7 +41,7 @@ Description:
 		by this network device. Note that the specific meaning might
 		depend on the MAC layer used by the interface.
 
-What:		/sys/class/<iface>/statistics/rx_dropped
+What:		/sys/class/net/<iface>/statistics/rx_dropped
 Date:		April 2005
 KernelVersion:	2.6.12
 Contact:	netdev@vger.kernel.org
@@ -51,7 +51,7 @@ Description:
 		packet processing. See the network driver for the exact
 		meaning of this value.
 
-What:		/sys/class/<iface>/statistics/rx_errors
+What:		/sys/class/net/<iface>/statistics/rx_errors
 Date:		April 2005
 KernelVersion:	2.6.12
 Contact:	netdev@vger.kernel.org
@@ -59,7 +59,7 @@ Description:
 		Indicates the number of receive errors on this network device.
 		See the network driver for the exact meaning of this value.
 
-What:		/sys/class/<iface>/statistics/rx_fifo_errors
+What:		/sys/class/net/<iface>/statistics/rx_fifo_errors
 Date:		April 2005
 KernelVersion:	2.6.12
 Contact:	netdev@vger.kernel.org
@@ -68,7 +68,7 @@ Description:
 		network device. See the network driver for the exact
 		meaning of this value.
 
-What:		/sys/class/<iface>/statistics/rx_frame_errors
+What:		/sys/class/net/<iface>/statistics/rx_frame_errors
 Date:		April 2005
 KernelVersion:	2.6.12
 Contact:	netdev@vger.kernel.org
@@ -78,7 +78,7 @@ Description:
 		on the MAC layer protocol used. See the network driver for
 		the exact meaning of this value.
 
-What:		/sys/class/<iface>/statistics/rx_length_errors
+What:		/sys/class/net/<iface>/statistics/rx_length_errors
 Date:		April 2005
 KernelVersion:	2.6.12
 Contact:	netdev@vger.kernel.org
@@ -87,7 +87,7 @@ Description:
 		error, oversized or undersized. See the network driver for the
 		exact meaning of this value.
 
-What:		/sys/class/<iface>/statistics/rx_missed_errors
+What:		/sys/class/net/<iface>/statistics/rx_missed_errors
 Date:		April 2005
 KernelVersion:	2.6.12
 Contact:	netdev@vger.kernel.org
@@ -96,7 +96,7 @@ Description:
 		due to lack of capacity in the receive side. See the network
 		driver for the exact meaning of this value.
 
-What:		/sys/class/<iface>/statistics/rx_nohandler
+What:		/sys/class/net/<iface>/statistics/rx_nohandler
 Date:		February 2016
 KernelVersion:	4.6
 Contact:	netdev@vger.kernel.org
@@ -104,7 +104,7 @@ Description:
 		Indicates the number of received packets that were dropped on
 		an inactive device by the network core.
 
-What:		/sys/class/<iface>/statistics/rx_over_errors
+What:		/sys/class/net/<iface>/statistics/rx_over_errors
 Date:		April 2005
 KernelVersion:	2.6.12
 Contact:	netdev@vger.kernel.org
@@ -114,7 +114,7 @@ Description:
 		(e.g: larger than MTU). See the network driver for the exact
 		meaning of this value.
 
-What:		/sys/class/<iface>/statistics/rx_packets
+What:		/sys/class/net/<iface>/statistics/rx_packets
 Date:		April 2005
 KernelVersion:	2.6.12
 Contact:	netdev@vger.kernel.org
@@ -122,7 +122,7 @@ Description:
 		Indicates the total number of good packets received by this
 		network device.
 
-What:		/sys/class/<iface>/statistics/tx_aborted_errors
+What:		/sys/class/net/<iface>/statistics/tx_aborted_errors
 Date:		April 2005
 KernelVersion:	2.6.12
 Contact:	netdev@vger.kernel.org
@@ -132,7 +132,7 @@ Description:
 		a medium collision). See the network driver for the exact
 		meaning of this value.
 
-What:		/sys/class/<iface>/statistics/tx_bytes
+What:		/sys/class/net/<iface>/statistics/tx_bytes
 Date:		April 2005
 KernelVersion:	2.6.12
 Contact:	netdev@vger.kernel.org
@@ -143,7 +143,7 @@ Description:
 		transmitted packets or all packets that have been queued for
 		transmission.
 
-What:		/sys/class/<iface>/statistics/tx_carrier_errors
+What:		/sys/class/net/<iface>/statistics/tx_carrier_errors
 Date:		April 2005
 KernelVersion:	2.6.12
 Contact:	netdev@vger.kernel.org
@@ -152,7 +152,7 @@ Description:
 		because of carrier errors (e.g: physical link down). See the
 		network driver for the exact meaning of this value.
 
-What:		/sys/class/<iface>/statistics/tx_compressed
+What:		/sys/class/net/<iface>/statistics/tx_compressed
 Date:		April 2005
 KernelVersion:	2.6.12
 Contact:	netdev@vger.kernel.org
@@ -161,7 +161,7 @@ Description:
 		this might only be relevant for devices that support
 		compression (e.g: PPP).
 
-What:		/sys/class/<iface>/statistics/tx_dropped
+What:		/sys/class/net/<iface>/statistics/tx_dropped
 Date:		April 2005
 KernelVersion:	2.6.12
 Contact:	netdev@vger.kernel.org
@@ -170,7 +170,7 @@ Description:
 		See the driver for the exact reasons as to why the packets were
 		dropped.
 
-What:		/sys/class/<iface>/statistics/tx_errors
+What:		/sys/class/net/<iface>/statistics/tx_errors
 Date:		April 2005
 KernelVersion:	2.6.12
 Contact:	netdev@vger.kernel.org
@@ -179,7 +179,7 @@ Description:
 		a network device. See the driver for the exact reasons as to
 		why the packets were dropped.
 
-What:		/sys/class/<iface>/statistics/tx_fifo_errors
+What:		/sys/class/net/<iface>/statistics/tx_fifo_errors
 Date:		April 2005
 KernelVersion:	2.6.12
 Contact:	netdev@vger.kernel.org
@@ -188,7 +188,7 @@ Description:
 		FIFO error. See the driver for the exact reasons as to why the
 		packets were dropped.
 
-What:		/sys/class/<iface>/statistics/tx_heartbeat_errors
+What:		/sys/class/net/<iface>/statistics/tx_heartbeat_errors
 Date:		April 2005
 KernelVersion:	2.6.12
 Contact:	netdev@vger.kernel.org
@@ -197,7 +197,7 @@ Description:
 		reported as heartbeat errors. See the driver for the exact
 		reasons as to why the packets were dropped.
 
-What:		/sys/class/<iface>/statistics/tx_packets
+What:		/sys/class/net/<iface>/statistics/tx_packets
 Date:		April 2005
 KernelVersion:	2.6.12
 Contact:	netdev@vger.kernel.org
@@ -206,7 +206,7 @@ Description:
 		device. See the driver for whether this reports the number of all
 		attempted or successful transmissions.
 
-What:		/sys/class/<iface>/statistics/tx_window_errors
+What:		/sys/class/net/<iface>/statistics/tx_window_errors
 Date:		April 2005
 KernelVersion:	2.6.12
 Contact:	netdev@vger.kernel.org
diff --git a/Documentation/ABI/testing/sysfs-devices-system-cpu b/Documentation/ABI/testing/sysfs-devices-system-cpu
index 13c01b641..78c26280c 100644
--- a/Documentation/ABI/testing/sysfs-devices-system-cpu
+++ b/Documentation/ABI/testing/sysfs-devices-system-cpu
@@ -519,6 +519,7 @@ 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 6828102ba..3e4a14e38 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.rst
    gather_data_sampling.rst
    srso
+   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 000000000..0585d02b9
--- /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 4ad60e127..2dfe75104 100644
--- a/Documentation/admin-guide/kernel-parameters.txt
+++ b/Documentation/admin-guide/kernel-parameters.txt
@@ -1107,6 +1107,26 @@
 			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
@@ -3262,6 +3282,7 @@
 					       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/arm64/silicon-errata.rst b/Documentation/arm64/silicon-errata.rst
index d9fce65b2..27135b9c0 100644
--- a/Documentation/arm64/silicon-errata.rst
+++ b/Documentation/arm64/silicon-errata.rst
@@ -221,3 +221,10 @@ stable kernels.
 +----------------+-----------------+-----------------+-----------------------------+
 | Fujitsu        | A64FX           | E#010001        | FUJITSU_ERRATUM_010001      |
 +----------------+-----------------+-----------------+-----------------------------+
++----------------+-----------------+-----------------+-----------------------------+
+| Microsoft      | Azure Cobalt 100| #2139208        | ARM64_ERRATUM_2139208       |
++----------------+-----------------+-----------------+-----------------------------+
+| Microsoft      | Azure Cobalt 100| #2067961        | ARM64_ERRATUM_2067961       |
++----------------+-----------------+-----------------+-----------------------------+
+| Microsoft      | Azure Cobalt 100| #2253138        | ARM64_ERRATUM_2253138       |
++----------------+-----------------+-----------------+-----------------------------+
diff --git a/Documentation/devicetree/bindings/net/wireless/marvell-8xxx.txt b/Documentation/devicetree/bindings/net/wireless/marvell-8xxx.txt
index 9bf9bbac1..cdc303caf 100644
--- a/Documentation/devicetree/bindings/net/wireless/marvell-8xxx.txt
+++ b/Documentation/devicetree/bindings/net/wireless/marvell-8xxx.txt
@@ -1,4 +1,4 @@
-Marvell 8787/8897/8997 (sd8787/sd8897/sd8997/pcie8997) SDIO/PCIE devices
+Marvell 8787/8897/8978/8997 (sd8787/sd8897/sd8978/sd8997/pcie8997) SDIO/PCIE devices
 ------
 
 This node provides properties for controlling the Marvell SDIO/PCIE wireless device.
@@ -10,7 +10,9 @@ Required properties:
   - compatible : should be one of the following:
 	* "marvell,sd8787"
 	* "marvell,sd8897"
+	* "marvell,sd8978"
 	* "marvell,sd8997"
+	* "nxp,iw416"
 	* "pci11ab,2b42"
 	* "pci1b4b,2b42"
 
diff --git a/Documentation/sound/soc/dapm.rst b/Documentation/sound/soc/dapm.rst
index 8e4410793..c3154ce6e 100644
--- a/Documentation/sound/soc/dapm.rst
+++ b/Documentation/sound/soc/dapm.rst
@@ -234,7 +234,7 @@ corresponding soft power control. In this case it is necessary to create
 a virtual widget - a widget with no control bits e.g.
 ::
 
-  SND_SOC_DAPM_MIXER("AC97 Mixer", SND_SOC_DAPM_NOPM, 0, 0, NULL, 0),
+  SND_SOC_DAPM_MIXER("AC97 Mixer", SND_SOC_NOPM, 0, 0, NULL, 0),
 
 This can be used to merge to signal paths together in software.
 
diff --git a/Documentation/x86/boot.rst b/Documentation/x86/boot.rst
index 894a19897..bac3789f3 100644
--- a/Documentation/x86/boot.rst
+++ b/Documentation/x86/boot.rst
@@ -1416,7 +1416,7 @@ execution context provided by the EFI firmware.
 
 The function prototype for the handover entry point looks like this::
 
-    efi_main(void *handle, efi_system_table_t *table, struct boot_params *bp)
+    efi_stub_entry(void *handle, efi_system_table_t *table, struct boot_params *bp)
 
 'handle' is the EFI image handle passed to the boot loader by the EFI
 firmware, 'table' is the EFI system table - these are the first two
diff --git a/Documentation/x86/mds.rst b/Documentation/x86/mds.rst
index 5d4330be2..e801df0bb 100644
--- a/Documentation/x86/mds.rst
+++ b/Documentation/x86/mds.rst
@@ -95,6 +95,9 @@ The kernel provides a function to invoke the buffer clearing:
 
     mds_clear_cpu_buffers()
 
+Also macro CLEAR_CPU_BUFFERS can be used in ASM late in exit-to-user path.
+Other than CFLAGS.ZF, this macro doesn't clobber any registers.
+
 The mitigation is invoked on kernel/userspace, hypervisor/guest and C-state
 (idle) transitions.
 
@@ -138,17 +141,30 @@ Mitigation points
 
    When transitioning from kernel to user space the CPU buffers are flushed
    on affected CPUs when the mitigation is not disabled on the kernel
-   command line. The migitation is enabled through the static key
-   mds_user_clear.
-
-   The mitigation is invoked in prepare_exit_to_usermode() which covers
-   all but one of the kernel to user space transitions.  The exception
-   is when we return from a Non Maskable Interrupt (NMI), which is
-   handled directly in do_nmi().
-
-   (The reason that NMI is special is that prepare_exit_to_usermode() can
-    enable IRQs.  In NMI context, NMIs are blocked, and we don't want to
-    enable IRQs with NMIs blocked.)
+   command line. The mitigation is enabled through the feature flag
+   X86_FEATURE_CLEAR_CPU_BUF.
+
+   The mitigation is invoked just before transitioning to userspace after
+   user registers are restored. This is done to minimize the window in
+   which kernel data could be accessed after VERW e.g. via an NMI after
+   VERW.
+
+   **Corner case not handled**
+   Interrupts returning to kernel don't clear CPUs buffers since the
+   exit-to-user path is expected to do that anyways. But, there could be
+   a case when an NMI is generated in kernel after the exit-to-user path
+   has cleared the buffers. This case is not handled and NMI returning to
+   kernel don't clear CPU buffers because:
+
+   1. It is rare to get an NMI after VERW, but before returning to userspace.
+   2. For an unprivileged user, there is no known way to make that NMI
+      less rare or target it.
+   3. It would take a large number of these precisely-timed NMIs to mount
+      an actual attack.  There's presumably not enough bandwidth.
+   4. The NMI in question occurs after a VERW, i.e. when user state is
+      restored and most interesting data is already scrubbed. Whats left
+      is only the data that NMI touches, and that may or may not be of
+      any interest.
 
 
 2. C-State transition