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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/vmscape.rst110
-rw-r--r--Documentation/admin-guide/kernel-parameters.txt11
-rw-r--r--Documentation/devicetree/bindings/dma/qcom,bam-dma.yaml4
-rw-r--r--Documentation/devicetree/bindings/phy/marvell,comphy-cp110.yaml29
-rw-r--r--Documentation/devicetree/bindings/phy/qcom,sc8280xp-qmp-pcie-phy.yaml4
-rw-r--r--Documentation/devicetree/bindings/serial/8250.yaml56
-rw-r--r--Documentation/devicetree/bindings/serial/brcm,bcm7271-uart.yaml2
-rw-r--r--Documentation/devicetree/bindings/spi/spi-fsl-lpspi.yaml5
-rw-r--r--Documentation/netlink/specs/mptcp_pm.yaml2
-rw-r--r--Documentation/networking/can.rst2
-rw-r--r--Documentation/networking/mptcp.rst8
-rw-r--r--Documentation/networking/napi.rst5
14 files changed, 195 insertions, 45 deletions
diff --git a/Documentation/ABI/testing/sysfs-devices-system-cpu b/Documentation/ABI/testing/sysfs-devices-system-cpu
index ab8cd337f43a..8aed6d94c4cd 100644
--- a/Documentation/ABI/testing/sysfs-devices-system-cpu
+++ b/Documentation/ABI/testing/sysfs-devices-system-cpu
@@ -586,6 +586,7 @@ What: /sys/devices/system/cpu/vulnerabilities
/sys/devices/system/cpu/vulnerabilities/srbds
/sys/devices/system/cpu/vulnerabilities/tsa
/sys/devices/system/cpu/vulnerabilities/tsx_async_abort
+ /sys/devices/system/cpu/vulnerabilities/vmscape
Date: January 2018
Contact: Linux kernel mailing list <linux-kernel@vger.kernel.org>
Description: Information about CPU vulnerabilities
diff --git a/Documentation/admin-guide/hw-vuln/index.rst b/Documentation/admin-guide/hw-vuln/index.rst
index 89ca636081b7..55d747511f83 100644
--- a/Documentation/admin-guide/hw-vuln/index.rst
+++ b/Documentation/admin-guide/hw-vuln/index.rst
@@ -26,3 +26,4 @@ are configurable at compile, boot or run time.
rsb
old_microcode
indirect-target-selection
+ vmscape
diff --git a/Documentation/admin-guide/hw-vuln/vmscape.rst b/Documentation/admin-guide/hw-vuln/vmscape.rst
new file mode 100644
index 000000000000..d9b9a2b6c114
--- /dev/null
+++ b/Documentation/admin-guide/hw-vuln/vmscape.rst
@@ -0,0 +1,110 @@
+.. SPDX-License-Identifier: GPL-2.0
+
+VMSCAPE
+=======
+
+VMSCAPE is a vulnerability that may allow a guest to influence the branch
+prediction in host userspace. It particularly affects hypervisors like QEMU.
+
+Even if a hypervisor may not have any sensitive data like disk encryption keys,
+guest-userspace may be able to attack the guest-kernel using the hypervisor as
+a confused deputy.
+
+Affected processors
+-------------------
+
+The following CPU families are affected by VMSCAPE:
+
+**Intel processors:**
+ - Skylake generation (Parts without Enhanced-IBRS)
+ - Cascade Lake generation - (Parts affected by ITS guest/host separation)
+ - Alder Lake and newer (Parts affected by BHI)
+
+Note that, BHI affected parts that use BHB clearing software mitigation e.g.
+Icelake are not vulnerable to VMSCAPE.
+
+**AMD processors:**
+ - Zen series (families 0x17, 0x19, 0x1a)
+
+** Hygon processors:**
+ - Family 0x18
+
+Mitigation
+----------
+
+Conditional IBPB
+----------------
+
+Kernel tracks when a CPU has run a potentially malicious guest and issues an
+IBPB before the first exit to userspace after VM-exit. If userspace did not run
+between VM-exit and the next VM-entry, no IBPB is issued.
+
+Note that the existing userspace mitigation against Spectre-v2 is effective in
+protecting the userspace. They are insufficient to protect the userspace VMMs
+from a malicious guest. This is because Spectre-v2 mitigations are applied at
+context switch time, while the userspace VMM can run after a VM-exit without a
+context switch.
+
+Vulnerability enumeration and mitigation is not applied inside a guest. This is
+because nested hypervisors should already be deploying IBPB to isolate
+themselves from nested guests.
+
+SMT considerations
+------------------
+
+When Simultaneous Multi-Threading (SMT) is enabled, hypervisors can be
+vulnerable to cross-thread attacks. For complete protection against VMSCAPE
+attacks in SMT environments, STIBP should be enabled.
+
+The kernel will issue a warning if SMT is enabled without adequate STIBP
+protection. Warning is not issued when:
+
+- SMT is disabled
+- STIBP is enabled system-wide
+- Intel eIBRS is enabled (which implies STIBP protection)
+
+System information and options
+------------------------------
+
+The sysfs file showing VMSCAPE mitigation status is:
+
+ /sys/devices/system/cpu/vulnerabilities/vmscape
+
+The possible values in this file are:
+
+ * 'Not affected':
+
+ The processor is not vulnerable to VMSCAPE attacks.
+
+ * 'Vulnerable':
+
+ The processor is vulnerable and no mitigation has been applied.
+
+ * 'Mitigation: IBPB before exit to userspace':
+
+ Conditional IBPB mitigation is enabled. The kernel tracks when a CPU has
+ run a potentially malicious guest and issues an IBPB before the first
+ exit to userspace after VM-exit.
+
+ * 'Mitigation: IBPB on VMEXIT':
+
+ IBPB is issued on every VM-exit. This occurs when other mitigations like
+ RETBLEED or SRSO are already issuing IBPB on VM-exit.
+
+Mitigation control on the kernel command line
+----------------------------------------------
+
+The mitigation can be controlled via the ``vmscape=`` command line parameter:
+
+ * ``vmscape=off``:
+
+ Disable the VMSCAPE mitigation.
+
+ * ``vmscape=ibpb``:
+
+ Enable conditional IBPB mitigation (default when CONFIG_MITIGATION_VMSCAPE=y).
+
+ * ``vmscape=force``:
+
+ Force vulnerability detection and mitigation even on processors that are
+ not known to be affected.
diff --git a/Documentation/admin-guide/kernel-parameters.txt b/Documentation/admin-guide/kernel-parameters.txt
index 747a55abf494..5a7a83c411e9 100644
--- a/Documentation/admin-guide/kernel-parameters.txt
+++ b/Documentation/admin-guide/kernel-parameters.txt
@@ -3829,6 +3829,7 @@
srbds=off [X86,INTEL]
ssbd=force-off [ARM64]
tsx_async_abort=off [X86]
+ vmscape=off [X86]
Exceptions:
This does not have any effect on
@@ -8041,6 +8042,16 @@
vmpoff= [KNL,S390] Perform z/VM CP command after power off.
Format: <command>
+ vmscape= [X86] Controls mitigation for VMscape attacks.
+ VMscape attacks can leak information from a userspace
+ hypervisor to a guest via speculative side-channels.
+
+ off - disable the mitigation
+ ibpb - use Indirect Branch Prediction Barrier
+ (IBPB) mitigation (default)
+ force - force vulnerability detection even on
+ unaffected processors
+
vsyscall= [X86-64,EARLY]
Controls the behavior of vsyscalls (i.e. calls to
fixed addresses of 0xffffffffff600x00 from legacy
diff --git a/Documentation/devicetree/bindings/dma/qcom,bam-dma.yaml b/Documentation/devicetree/bindings/dma/qcom,bam-dma.yaml
index f2f87f0f545b..6493a6968bb4 100644
--- a/Documentation/devicetree/bindings/dma/qcom,bam-dma.yaml
+++ b/Documentation/devicetree/bindings/dma/qcom,bam-dma.yaml
@@ -92,8 +92,12 @@ required:
anyOf:
- required:
- qcom,powered-remotely
+ - num-channels
+ - qcom,num-ees
- required:
- qcom,controlled-remotely
+ - num-channels
+ - qcom,num-ees
- required:
- clocks
- clock-names
diff --git a/Documentation/devicetree/bindings/phy/marvell,comphy-cp110.yaml b/Documentation/devicetree/bindings/phy/marvell,comphy-cp110.yaml
index d9501df42886..c35d31642805 100644
--- a/Documentation/devicetree/bindings/phy/marvell,comphy-cp110.yaml
+++ b/Documentation/devicetree/bindings/phy/marvell,comphy-cp110.yaml
@@ -47,21 +47,19 @@ properties:
const: 0
clocks:
+ minItems: 1
maxItems: 3
- description: Reference clocks for CP110; MG clock, MG Core clock, AXI clock
clock-names:
- items:
- - const: mg_clk
- - const: mg_core_clk
- - const: axi_clk
+ minItems: 1
+ maxItems: 3
marvell,system-controller:
description: Phandle to the Marvell system controller (CP110 only)
$ref: /schemas/types.yaml#/definitions/phandle
patternProperties:
- '^phy@[0-2]$':
+ '^phy@[0-5]$':
description: A COMPHY lane child node
type: object
additionalProperties: false
@@ -69,10 +67,14 @@ patternProperties:
properties:
reg:
description: COMPHY lane number
+ maximum: 5
'#phy-cells':
const: 1
+ connector:
+ type: object
+
required:
- reg
- '#phy-cells'
@@ -91,13 +93,24 @@ allOf:
then:
properties:
- clocks: false
- clock-names: false
+ clocks:
+ maxItems: 1
+ clock-names:
+ const: xtal
required:
- reg-names
else:
+ properties:
+ clocks:
+ minItems: 3
+ clock-names:
+ items:
+ - const: mg_clk
+ - const: mg_core_clk
+ - const: axi_clk
+
required:
- marvell,system-controller
diff --git a/Documentation/devicetree/bindings/phy/qcom,sc8280xp-qmp-pcie-phy.yaml b/Documentation/devicetree/bindings/phy/qcom,sc8280xp-qmp-pcie-phy.yaml
index a1ae8c7988c8..b6f140bf5b3b 100644
--- a/Documentation/devicetree/bindings/phy/qcom,sc8280xp-qmp-pcie-phy.yaml
+++ b/Documentation/devicetree/bindings/phy/qcom,sc8280xp-qmp-pcie-phy.yaml
@@ -176,6 +176,8 @@ allOf:
compatible:
contains:
enum:
+ - qcom,sa8775p-qmp-gen4x2-pcie-phy
+ - qcom,sa8775p-qmp-gen4x4-pcie-phy
- qcom,sc8280xp-qmp-gen3x1-pcie-phy
- qcom,sc8280xp-qmp-gen3x2-pcie-phy
- qcom,sc8280xp-qmp-gen3x4-pcie-phy
@@ -197,8 +199,6 @@ allOf:
contains:
enum:
- qcom,qcs8300-qmp-gen4x2-pcie-phy
- - qcom,sa8775p-qmp-gen4x2-pcie-phy
- - qcom,sa8775p-qmp-gen4x4-pcie-phy
then:
properties:
clocks:
diff --git a/Documentation/devicetree/bindings/serial/8250.yaml b/Documentation/devicetree/bindings/serial/8250.yaml
index e46bee8d25bf..b243afa69a1a 100644
--- a/Documentation/devicetree/bindings/serial/8250.yaml
+++ b/Documentation/devicetree/bindings/serial/8250.yaml
@@ -48,7 +48,6 @@ allOf:
oneOf:
- required: [ clock-frequency ]
- required: [ clocks ]
-
- if:
properties:
compatible:
@@ -60,12 +59,39 @@ allOf:
items:
- const: uartclk
- const: reg
- else:
+ - if:
+ properties:
+ compatible:
+ contains:
+ const: spacemit,k1-uart
+ then:
properties:
clock-names:
items:
- const: core
- const: bus
+ - if:
+ properties:
+ compatible:
+ contains:
+ enum:
+ - spacemit,k1-uart
+ - nxp,lpc1850-uart
+ then:
+ required:
+ - clocks
+ - clock-names
+ properties:
+ clocks:
+ minItems: 2
+ clock-names:
+ minItems: 2
+ else:
+ properties:
+ clocks:
+ maxItems: 1
+ clock-names:
+ maxItems: 1
properties:
compatible:
@@ -162,6 +188,9 @@ properties:
minItems: 1
maxItems: 2
oneOf:
+ - enum:
+ - main
+ - uart
- items:
- const: core
- const: bus
@@ -264,29 +293,6 @@ required:
- reg
- interrupts
-if:
- properties:
- compatible:
- contains:
- enum:
- - spacemit,k1-uart
- - nxp,lpc1850-uart
-then:
- required:
- - clocks
- - clock-names
- properties:
- clocks:
- minItems: 2
- clock-names:
- minItems: 2
-else:
- properties:
- clocks:
- maxItems: 1
- clock-names:
- maxItems: 1
-
unevaluatedProperties: false
examples:
diff --git a/Documentation/devicetree/bindings/serial/brcm,bcm7271-uart.yaml b/Documentation/devicetree/bindings/serial/brcm,bcm7271-uart.yaml
index 89c462653e2d..8cc848ae11cb 100644
--- a/Documentation/devicetree/bindings/serial/brcm,bcm7271-uart.yaml
+++ b/Documentation/devicetree/bindings/serial/brcm,bcm7271-uart.yaml
@@ -41,7 +41,7 @@ properties:
- const: dma_intr2
clocks:
- minItems: 1
+ maxItems: 1
clock-names:
const: sw_baud
diff --git a/Documentation/devicetree/bindings/spi/spi-fsl-lpspi.yaml b/Documentation/devicetree/bindings/spi/spi-fsl-lpspi.yaml
index a65a42ccaafe..a82360bed188 100644
--- a/Documentation/devicetree/bindings/spi/spi-fsl-lpspi.yaml
+++ b/Documentation/devicetree/bindings/spi/spi-fsl-lpspi.yaml
@@ -20,6 +20,7 @@ properties:
- enum:
- fsl,imx7ulp-spi
- fsl,imx8qxp-spi
+ - nxp,s32g2-lpspi
- items:
- enum:
- fsl,imx8ulp-spi
@@ -27,6 +28,10 @@ properties:
- fsl,imx94-spi
- fsl,imx95-spi
- const: fsl,imx7ulp-spi
+ - items:
+ - const: nxp,s32g3-lpspi
+ - const: nxp,s32g2-lpspi
+
reg:
maxItems: 1
diff --git a/Documentation/netlink/specs/mptcp_pm.yaml b/Documentation/netlink/specs/mptcp_pm.yaml
index 02f1ddcfbf1c..d15335684ec3 100644
--- a/Documentation/netlink/specs/mptcp_pm.yaml
+++ b/Documentation/netlink/specs/mptcp_pm.yaml
@@ -256,7 +256,7 @@ attribute-sets:
type: u32
-
name: if-idx
- type: u32
+ type: s32
-
name: reset-reason
type: u32
diff --git a/Documentation/networking/can.rst b/Documentation/networking/can.rst
index bc1b585355f7..7650c4b5be5f 100644
--- a/Documentation/networking/can.rst
+++ b/Documentation/networking/can.rst
@@ -742,7 +742,7 @@ The broadcast manager sends responses to user space in the same form:
struct timeval ival1, ival2; /* count and subsequent interval */
canid_t can_id; /* unique can_id for task */
__u32 nframes; /* number of can_frames following */
- struct can_frame frames[0];
+ struct can_frame frames[];
};
The aligned payload 'frames' uses the same basic CAN frame structure defined
diff --git a/Documentation/networking/mptcp.rst b/Documentation/networking/mptcp.rst
index 17f2bab61164..2e31038d6462 100644
--- a/Documentation/networking/mptcp.rst
+++ b/Documentation/networking/mptcp.rst
@@ -60,10 +60,10 @@ address announcements. Typically, it is the client side that initiates subflows,
and the server side that announces additional addresses via the ``ADD_ADDR`` and
``REMOVE_ADDR`` options.
-Path managers are controlled by the ``net.mptcp.pm_type`` sysctl knob -- see
-mptcp-sysctl.rst. There are two types: the in-kernel one (type ``0``) where the
-same rules are applied for all the connections (see: ``ip mptcp``) ; and the
-userspace one (type ``1``), controlled by a userspace daemon (i.e. `mptcpd
+Path managers are controlled by the ``net.mptcp.path_manager`` sysctl knob --
+see mptcp-sysctl.rst. There are two types: the in-kernel one (``kernel``) where
+the same rules are applied for all the connections (see: ``ip mptcp``) ; and the
+userspace one (``userspace``), controlled by a userspace daemon (i.e. `mptcpd
<https://mptcpd.mptcp.dev/>`_) where different rules can be applied for each
connection. The path managers can be controlled via a Netlink API; see
netlink_spec/mptcp_pm.rst.
diff --git a/Documentation/networking/napi.rst b/Documentation/networking/napi.rst
index a15754adb041..7dd60366f4ff 100644
--- a/Documentation/networking/napi.rst
+++ b/Documentation/networking/napi.rst
@@ -433,9 +433,8 @@ Threaded NAPI
Threaded NAPI is an operating mode that uses dedicated kernel
threads rather than software IRQ context for NAPI processing.
-The configuration is per netdevice and will affect all
-NAPI instances of that device. Each NAPI instance will spawn a separate
-thread (called ``napi/${ifc-name}-${napi-id}``).
+Each threaded NAPI instance will spawn a separate thread
+(called ``napi/${ifc-name}-${napi-id}``).
It is recommended to pin each kernel thread to a single CPU, the same
CPU as the CPU which services the interrupt. Note that the mapping