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-rw-r--r--Documentation/ABI/obsolete/sysfs-class-dax22
-rw-r--r--Documentation/ABI/testing/sysfs-fs-f2fs7
-rw-r--r--Documentation/acpi/aml-debugger.txt4
-rw-r--r--Documentation/admin-guide/md.rst3
-rw-r--r--Documentation/arm/kernel_mode_neon.txt4
-rw-r--r--Documentation/devicetree/bindings/clock/actions,owl-cmu.txt7
-rw-r--r--Documentation/devicetree/bindings/clock/amlogic,gxbb-aoclkc.txt1
-rw-r--r--Documentation/devicetree/bindings/clock/amlogic,gxbb-clkc.txt1
-rw-r--r--Documentation/devicetree/bindings/clock/exynos5433-clock.txt23
-rw-r--r--Documentation/devicetree/bindings/clock/fixed-clock.txt23
-rw-r--r--Documentation/devicetree/bindings/clock/fixed-clock.yaml44
-rw-r--r--Documentation/devicetree/bindings/clock/fixed-factor-clock.txt28
-rw-r--r--Documentation/devicetree/bindings/clock/fixed-factor-clock.yaml56
-rw-r--r--Documentation/devicetree/bindings/clock/fixed-mmio-clock.txt24
-rw-r--r--Documentation/devicetree/bindings/clock/imx8mm-clock.txt29
-rw-r--r--Documentation/devicetree/bindings/clock/qcom,rpmcc.txt1
-rw-r--r--Documentation/devicetree/bindings/display/ssd1307fb.txt2
-rw-r--r--Documentation/devicetree/bindings/dma/dma.txt4
-rw-r--r--Documentation/devicetree/bindings/dma/fsl-qdma.txt57
-rw-r--r--Documentation/devicetree/bindings/dma/k3dma.txt4
-rw-r--r--Documentation/devicetree/bindings/dma/snps-dma.txt2
-rw-r--r--Documentation/devicetree/bindings/dma/sprd-dma.txt2
-rw-r--r--Documentation/devicetree/bindings/dma/xilinx/xilinx_dma.txt7
-rw-r--r--Documentation/devicetree/bindings/net/dsa/dsa.txt5
-rw-r--r--Documentation/devicetree/bindings/remoteproc/qcom,adsp-pil.txt5
-rw-r--r--Documentation/devicetree/bindings/remoteproc/qcom,adsp.txt23
-rw-r--r--Documentation/devicetree/bindings/remoteproc/qcom,q6v5.txt79
-rw-r--r--Documentation/driver-api/dmaengine/client.rst2
-rw-r--r--Documentation/driver-api/dmaengine/dmatest.rst1
-rw-r--r--Documentation/driver-model/devres.txt2
-rw-r--r--Documentation/filesystems/cifs/TODO3
-rw-r--r--Documentation/filesystems/cifs/cifs.txt34
-rw-r--r--Documentation/filesystems/f2fs.txt2
-rw-r--r--Documentation/virtual/kvm/api.txt17
-rw-r--r--Documentation/virtual/kvm/halt-polling.txt37
-rw-r--r--Documentation/virtual/kvm/mmu.txt41
36 files changed, 467 insertions, 139 deletions
diff --git a/Documentation/ABI/obsolete/sysfs-class-dax b/Documentation/ABI/obsolete/sysfs-class-dax
new file mode 100644
index 000000000000..2cb9fc5e8bd1
--- /dev/null
+++ b/Documentation/ABI/obsolete/sysfs-class-dax
@@ -0,0 +1,22 @@
+What: /sys/class/dax/
+Date: May, 2016
+KernelVersion: v4.7
+Contact: linux-nvdimm@lists.01.org
+Description: Device DAX is the device-centric analogue of Filesystem
+ DAX (CONFIG_FS_DAX). It allows memory ranges to be
+ allocated and mapped without need of an intervening file
+ system. Device DAX is strict, precise and predictable.
+ Specifically this interface:
+
+ 1/ Guarantees fault granularity with respect to a given
+ page size (pte, pmd, or pud) set at configuration time.
+
+ 2/ Enforces deterministic behavior by being strict about
+ what fault scenarios are supported.
+
+ The /sys/class/dax/ interface enumerates all the
+ device-dax instances in the system. The ABI is
+ deprecated and will be removed after 2020. It is
+ replaced with the DAX bus interface /sys/bus/dax/ where
+ device-dax instances can be found under
+ /sys/bus/dax/devices/
diff --git a/Documentation/ABI/testing/sysfs-fs-f2fs b/Documentation/ABI/testing/sysfs-fs-f2fs
index a7ce33199457..91822ce25831 100644
--- a/Documentation/ABI/testing/sysfs-fs-f2fs
+++ b/Documentation/ABI/testing/sysfs-fs-f2fs
@@ -86,6 +86,13 @@ Description:
The unit size is one block, now only support configuring in range
of [1, 512].
+What: /sys/fs/f2fs/<disk>/umount_discard_timeout
+Date: January 2019
+Contact: "Jaegeuk Kim" <jaegeuk@kernel.org>
+Description:
+ Set timeout to issue discard commands during umount.
+ Default: 5 secs
+
What: /sys/fs/f2fs/<disk>/max_victim_search
Date: January 2014
Contact: "Jaegeuk Kim" <jaegeuk.kim@samsung.com>
diff --git a/Documentation/acpi/aml-debugger.txt b/Documentation/acpi/aml-debugger.txt
index e851cc5de63f..75ebeb64ab29 100644
--- a/Documentation/acpi/aml-debugger.txt
+++ b/Documentation/acpi/aml-debugger.txt
@@ -23,7 +23,7 @@ kernel.
The resultant userspace tool binary is then located at:
- tools/acpi/power/acpi/acpidbg/acpidbg
+ tools/power/acpi/acpidbg
It can be installed to system directories by running "make install" (as a
sufficiently privileged user).
@@ -35,7 +35,7 @@ kernel.
# mount -t debugfs none /sys/kernel/debug
# modprobe acpi_dbg
- # tools/acpi/power/acpi/acpidbg/acpidbg
+ # tools/power/acpi/acpidbg
That spawns the interactive AML debugger environment where you can execute
debugger commands.
diff --git a/Documentation/admin-guide/md.rst b/Documentation/admin-guide/md.rst
index 84de718f24a4..3c51084ffd37 100644
--- a/Documentation/admin-guide/md.rst
+++ b/Documentation/admin-guide/md.rst
@@ -756,3 +756,6 @@ These currently include:
The cache mode for raid5. raid5 could include an extra disk for
caching. The mode can be "write-throuth" and "write-back". The
default is "write-through".
+
+ ppl_write_hint
+ NVMe stream ID to be set for each PPL write request.
diff --git a/Documentation/arm/kernel_mode_neon.txt b/Documentation/arm/kernel_mode_neon.txt
index 525452726d31..b9e060c5b61e 100644
--- a/Documentation/arm/kernel_mode_neon.txt
+++ b/Documentation/arm/kernel_mode_neon.txt
@@ -6,7 +6,7 @@ TL;DR summary
* Use only NEON instructions, or VFP instructions that don't rely on support
code
* Isolate your NEON code in a separate compilation unit, and compile it with
- '-mfpu=neon -mfloat-abi=softfp'
+ '-march=armv7-a -mfpu=neon -mfloat-abi=softfp'
* Put kernel_neon_begin() and kernel_neon_end() calls around the calls into your
NEON code
* Don't sleep in your NEON code, and be aware that it will be executed with
@@ -87,7 +87,7 @@ instructions appearing in unexpected places if no special care is taken.
Therefore, the recommended and only supported way of using NEON/VFP in the
kernel is by adhering to the following rules:
* isolate the NEON code in a separate compilation unit and compile it with
- '-mfpu=neon -mfloat-abi=softfp';
+ '-march=armv7-a -mfpu=neon -mfloat-abi=softfp';
* issue the calls to kernel_neon_begin(), kernel_neon_end() as well as the calls
into the unit containing the NEON code from a compilation unit which is *not*
built with the GCC flag '-mfpu=neon' set.
diff --git a/Documentation/devicetree/bindings/clock/actions,owl-cmu.txt b/Documentation/devicetree/bindings/clock/actions,owl-cmu.txt
index 2ef86ae96df8..d19885b7c73f 100644
--- a/Documentation/devicetree/bindings/clock/actions,owl-cmu.txt
+++ b/Documentation/devicetree/bindings/clock/actions,owl-cmu.txt
@@ -2,13 +2,14 @@
The Actions Semi Owl Clock Management Unit generates and supplies clock
to various controllers within the SoC. The clock binding described here is
-applicable to S900 and S700 SoC's.
+applicable to S900, S700 and S500 SoC's.
Required Properties:
- compatible: should be one of the following,
"actions,s900-cmu"
"actions,s700-cmu"
+ "actions,s500-cmu"
- reg: physical base address of the controller and length of memory mapped
region.
- clocks: Reference to the parent clocks ("hosc", "losc")
@@ -19,8 +20,8 @@ Each clock is assigned an identifier, and client nodes can use this identifier
to specify the clock which they consume.
All available clocks are defined as preprocessor macros in corresponding
-dt-bindings/clock/actions,s900-cmu.h or actions,s700-cmu.h header and can be
-used in device tree sources.
+dt-bindings/clock/actions,s900-cmu.h or actions,s700-cmu.h or
+actions,s500-cmu.h header and can be used in device tree sources.
External clocks:
diff --git a/Documentation/devicetree/bindings/clock/amlogic,gxbb-aoclkc.txt b/Documentation/devicetree/bindings/clock/amlogic,gxbb-aoclkc.txt
index 79511d7bb321..c41f0be5d438 100644
--- a/Documentation/devicetree/bindings/clock/amlogic,gxbb-aoclkc.txt
+++ b/Documentation/devicetree/bindings/clock/amlogic,gxbb-aoclkc.txt
@@ -10,6 +10,7 @@ Required Properties:
- GXL (S905X, S905D) : "amlogic,meson-gxl-aoclkc"
- GXM (S912) : "amlogic,meson-gxm-aoclkc"
- AXG (A113D, A113X) : "amlogic,meson-axg-aoclkc"
+ - G12A (S905X2, S905D2, S905Y2) : "amlogic,meson-g12a-aoclkc"
followed by the common "amlogic,meson-gx-aoclkc"
- clocks: list of clock phandle, one for each entry clock-names.
- clock-names: should contain the following:
diff --git a/Documentation/devicetree/bindings/clock/amlogic,gxbb-clkc.txt b/Documentation/devicetree/bindings/clock/amlogic,gxbb-clkc.txt
index a6871953bf04..5c8b105be4d6 100644
--- a/Documentation/devicetree/bindings/clock/amlogic,gxbb-clkc.txt
+++ b/Documentation/devicetree/bindings/clock/amlogic,gxbb-clkc.txt
@@ -9,6 +9,7 @@ Required Properties:
"amlogic,gxbb-clkc" for GXBB SoC,
"amlogic,gxl-clkc" for GXL and GXM SoC,
"amlogic,axg-clkc" for AXG SoC.
+ "amlogic,g12a-clkc" for G12A SoC.
- clocks : list of clock phandle, one for each entry clock-names.
- clock-names : should contain the following:
* "xtal": the platform xtal
diff --git a/Documentation/devicetree/bindings/clock/exynos5433-clock.txt b/Documentation/devicetree/bindings/clock/exynos5433-clock.txt
index 50d5897c9849..183c327a7d6b 100644
--- a/Documentation/devicetree/bindings/clock/exynos5433-clock.txt
+++ b/Documentation/devicetree/bindings/clock/exynos5433-clock.txt
@@ -50,6 +50,8 @@ Required Properties:
IPs.
- "samsung,exynos5433-cmu-cam1" - clock controller compatible for CMU_CAM1
which generates clocks for Cortex-A5/MIPI_CSIS2/FIMC-LITE_C/FIMC-FD IPs.
+ - "samsung,exynos5433-cmu-imem" - clock controller compatible for CMU_IMEM
+ which generates clocks for SSS (Security SubSystem) and SlimSSS IPs.
- reg: physical base address of the controller and length of memory mapped
region.
@@ -168,6 +170,12 @@ Required Properties:
- aclk_cam1_400
- aclk_cam1_552
+ Input clocks for imem clock controller:
+ - oscclk
+ - aclk_imem_sssx_266
+ - aclk_imem_266
+ - aclk_imem_200
+
Optional properties:
- power-domains: a phandle to respective power domain node as described by
generic PM domain bindings (see power/power_domain.txt for more
@@ -469,6 +477,21 @@ Example 2: Examples of clock controller nodes are listed below.
power-domains = <&pd_cam1>;
};
+ cmu_imem: clock-controller@11060000 {
+ compatible = "samsung,exynos5433-cmu-imem";
+ reg = <0x11060000 0x1000>;
+ #clock-cells = <1>;
+
+ clock-names = "oscclk",
+ "aclk_imem_sssx_266",
+ "aclk_imem_266",
+ "aclk_imem_200";
+ clocks = <&xxti>,
+ <&cmu_top CLK_DIV_ACLK_IMEM_SSSX_266>,
+ <&cmu_top CLK_DIV_ACLK_IMEM_266>,
+ <&cmu_top CLK_DIV_ACLK_IMEM_200>;
+ };
+
Example 3: UART controller node that consumes the clock generated by the clock
controller.
diff --git a/Documentation/devicetree/bindings/clock/fixed-clock.txt b/Documentation/devicetree/bindings/clock/fixed-clock.txt
deleted file mode 100644
index 0641a663ad69..000000000000
--- a/Documentation/devicetree/bindings/clock/fixed-clock.txt
+++ /dev/null
@@ -1,23 +0,0 @@
-Binding for simple fixed-rate clock sources.
-
-This binding uses the common clock binding[1].
-
-[1] Documentation/devicetree/bindings/clock/clock-bindings.txt
-
-Required properties:
-- compatible : shall be "fixed-clock".
-- #clock-cells : from common clock binding; shall be set to 0.
-- clock-frequency : frequency of clock in Hz. Should be a single cell.
-
-Optional properties:
-- clock-accuracy : accuracy of clock in ppb (parts per billion).
- Should be a single cell.
-- clock-output-names : From common clock binding.
-
-Example:
- clock {
- compatible = "fixed-clock";
- #clock-cells = <0>;
- clock-frequency = <1000000000>;
- clock-accuracy = <100>;
- };
diff --git a/Documentation/devicetree/bindings/clock/fixed-clock.yaml b/Documentation/devicetree/bindings/clock/fixed-clock.yaml
new file mode 100644
index 000000000000..b657ecd0ef1c
--- /dev/null
+++ b/Documentation/devicetree/bindings/clock/fixed-clock.yaml
@@ -0,0 +1,44 @@
+# SPDX-License-Identifier: GPL-2.0
+%YAML 1.2
+---
+$id: http://devicetree.org/schemas/clock/fixed-clock.yaml#
+$schema: http://devicetree.org/meta-schemas/core.yaml#
+
+title: Binding for simple fixed-rate clock sources
+
+maintainers:
+ - Michael Turquette <mturquette@baylibre.com>
+ - Stephen Boyd <sboyd@kernel.org>
+
+properties:
+ compatible:
+ const: fixed-clock
+
+ "#clock-cells":
+ const: 0
+
+ clock-frequency: true
+
+ clock-accuracy:
+ description: accuracy of clock in ppb (parts per billion).
+ $ref: /schemas/types.yaml#/definitions/uint32
+
+ clock-output-names:
+ maxItems: 1
+
+required:
+ - compatible
+ - "#clock-cells"
+ - clock-frequency
+
+additionalProperties: false
+
+examples:
+ - |
+ clock {
+ compatible = "fixed-clock";
+ #clock-cells = <0>;
+ clock-frequency = <1000000000>;
+ clock-accuracy = <100>;
+ };
+...
diff --git a/Documentation/devicetree/bindings/clock/fixed-factor-clock.txt b/Documentation/devicetree/bindings/clock/fixed-factor-clock.txt
deleted file mode 100644
index 189467a7188a..000000000000
--- a/Documentation/devicetree/bindings/clock/fixed-factor-clock.txt
+++ /dev/null
@@ -1,28 +0,0 @@
-Binding for simple fixed factor rate clock sources.
-
-This binding uses the common clock binding[1].
-
-[1] Documentation/devicetree/bindings/clock/clock-bindings.txt
-
-Required properties:
-- compatible : shall be "fixed-factor-clock".
-- #clock-cells : from common clock binding; shall be set to 0.
-- clock-div: fixed divider.
-- clock-mult: fixed multiplier.
-- clocks: parent clock.
-
-Optional properties:
-- clock-output-names : From common clock binding.
-
-Some clocks that require special treatments are also handled by that
-driver, with the compatibles:
- - allwinner,sun4i-a10-pll3-2x-clk
-
-Example:
- clock {
- compatible = "fixed-factor-clock";
- clocks = <&parentclk>;
- #clock-cells = <0>;
- clock-div = <2>;
- clock-mult = <1>;
- };
diff --git a/Documentation/devicetree/bindings/clock/fixed-factor-clock.yaml b/Documentation/devicetree/bindings/clock/fixed-factor-clock.yaml
new file mode 100644
index 000000000000..b567f8092f8c
--- /dev/null
+++ b/Documentation/devicetree/bindings/clock/fixed-factor-clock.yaml
@@ -0,0 +1,56 @@
+# SPDX-License-Identifier: GPL-2.0
+%YAML 1.2
+---
+$id: http://devicetree.org/schemas/clock/fixed-factor-clock.yaml#
+$schema: http://devicetree.org/meta-schemas/core.yaml#
+
+title: Binding for simple fixed factor rate clock sources
+
+maintainers:
+ - Michael Turquette <mturquette@baylibre.com>
+ - Stephen Boyd <sboyd@kernel.org>
+
+properties:
+ compatible:
+ enum:
+ - allwinner,sun4i-a10-pll3-2x-clk
+ - fixed-factor-clock
+
+ "#clock-cells":
+ const: 0
+
+ clocks:
+ maxItems: 1
+
+ clock-div:
+ description: Fixed divider
+ allOf:
+ - $ref: /schemas/types.yaml#/definitions/uint32
+ - minimum: 1
+
+ clock-mult:
+ description: Fixed multiplier
+ $ref: /schemas/types.yaml#/definitions/uint32
+
+ clock-output-names:
+ maxItems: 1
+
+required:
+ - compatible
+ - clocks
+ - "#clock-cells"
+ - clock-div
+ - clock-mult
+
+additionalProperties: false
+
+examples:
+ - |
+ clock {
+ compatible = "fixed-factor-clock";
+ clocks = <&parentclk>;
+ #clock-cells = <0>;
+ clock-div = <2>;
+ clock-mult = <1>;
+ };
+...
diff --git a/Documentation/devicetree/bindings/clock/fixed-mmio-clock.txt b/Documentation/devicetree/bindings/clock/fixed-mmio-clock.txt
new file mode 100644
index 000000000000..c359367fd1a9
--- /dev/null
+++ b/Documentation/devicetree/bindings/clock/fixed-mmio-clock.txt
@@ -0,0 +1,24 @@
+Binding for simple memory mapped io fixed-rate clock sources.
+The driver reads a clock frequency value from a single 32-bit memory mapped
+I/O register and registers it as a fixed rate clock.
+
+It was designed for test systems, like FPGA, not for complete, finished SoCs.
+
+This binding uses the common clock binding[1].
+
+[1] Documentation/devicetree/bindings/clock/clock-bindings.txt
+
+Required properties:
+- compatible : shall be "fixed-mmio-clock".
+- #clock-cells : from common clock binding; shall be set to 0.
+- reg : Address and length of the clock value register set.
+
+Optional properties:
+- clock-output-names : From common clock binding.
+
+Example:
+sysclock: sysclock@fd020004 {
+ #clock-cells = <0>;
+ compatible = "fixed-mmio-clock";
+ reg = <0xfd020004 0x4>;
+};
diff --git a/Documentation/devicetree/bindings/clock/imx8mm-clock.txt b/Documentation/devicetree/bindings/clock/imx8mm-clock.txt
new file mode 100644
index 000000000000..8e4ab9e619a1
--- /dev/null
+++ b/Documentation/devicetree/bindings/clock/imx8mm-clock.txt
@@ -0,0 +1,29 @@
+* Clock bindings for NXP i.MX8M Mini
+
+Required properties:
+- compatible: Should be "fsl,imx8mm-ccm"
+- reg: Address and length of the register set
+- #clock-cells: Should be <1>
+- clocks: list of clock specifiers, must contain an entry for each required
+ entry in clock-names
+- clock-names: should include the following entries:
+ - "osc_32k"
+ - "osc_24m"
+ - "clk_ext1"
+ - "clk_ext2"
+ - "clk_ext3"
+ - "clk_ext4"
+
+clk: clock-controller@30380000 {
+ compatible = "fsl,imx8mm-ccm";
+ reg = <0x0 0x30380000 0x0 0x10000>;
+ #clock-cells = <1>;
+ clocks = <&osc_32k>, <&osc_24m>, <&clk_ext1>, <&clk_ext2>,
+ <&clk_ext3>, <&clk_ext4>;
+ clock-names = "osc_32k", "osc_24m", "clk_ext1", "clk_ext2",
+ "clk_ext3", "clk_ext4";
+};
+
+The clock consumer should specify the desired clock by having the clock
+ID in its "clocks" phandle cell. See include/dt-bindings/clock/imx8mm-clock.h
+for the full list of i.MX8M Mini clock IDs.
diff --git a/Documentation/devicetree/bindings/clock/qcom,rpmcc.txt b/Documentation/devicetree/bindings/clock/qcom,rpmcc.txt
index 87b4949e9bc8..944719bd586f 100644
--- a/Documentation/devicetree/bindings/clock/qcom,rpmcc.txt
+++ b/Documentation/devicetree/bindings/clock/qcom,rpmcc.txt
@@ -16,6 +16,7 @@ Required properties :
"qcom,rpmcc-msm8974", "qcom,rpmcc"
"qcom,rpmcc-apq8064", "qcom,rpmcc"
"qcom,rpmcc-msm8996", "qcom,rpmcc"
+ "qcom,rpmcc-msm8998", "qcom,rpmcc"
"qcom,rpmcc-qcs404", "qcom,rpmcc"
- #clock-cells : shall contain 1
diff --git a/Documentation/devicetree/bindings/display/ssd1307fb.txt b/Documentation/devicetree/bindings/display/ssd1307fb.txt
index 209d931ef16c..b67f8caa212c 100644
--- a/Documentation/devicetree/bindings/display/ssd1307fb.txt
+++ b/Documentation/devicetree/bindings/display/ssd1307fb.txt
@@ -36,7 +36,6 @@ ssd1307: oled@3c {
reg = <0x3c>;
pwms = <&pwm 4 3000>;
reset-gpios = <&gpio2 7>;
- reset-active-low;
};
ssd1306: oled@3c {
@@ -44,7 +43,6 @@ ssd1306: oled@3c {
reg = <0x3c>;
pwms = <&pwm 4 3000>;
reset-gpios = <&gpio2 7>;
- reset-active-low;
solomon,com-lrremap;
solomon,com-invdir;
solomon,com-offset = <32>;
diff --git a/Documentation/devicetree/bindings/dma/dma.txt b/Documentation/devicetree/bindings/dma/dma.txt
index 6312fb00ce8d..eeb4e4d1771e 100644
--- a/Documentation/devicetree/bindings/dma/dma.txt
+++ b/Documentation/devicetree/bindings/dma/dma.txt
@@ -16,6 +16,9 @@ Optional properties:
- dma-channels: Number of DMA channels supported by the controller.
- dma-requests: Number of DMA request signals supported by the
controller.
+- dma-channel-mask: Bitmask of available DMA channels in ascending order
+ that are not reserved by firmware and are available to
+ the kernel. i.e. first channel corresponds to LSB.
Example:
@@ -29,6 +32,7 @@ Example:
#dma-cells = <1>;
dma-channels = <32>;
dma-requests = <127>;
+ dma-channel-mask = <0xfffe>
};
* DMA router
diff --git a/Documentation/devicetree/bindings/dma/fsl-qdma.txt b/Documentation/devicetree/bindings/dma/fsl-qdma.txt
new file mode 100644
index 000000000000..6a0ff9059e72
--- /dev/null
+++ b/Documentation/devicetree/bindings/dma/fsl-qdma.txt
@@ -0,0 +1,57 @@
+NXP Layerscape SoC qDMA Controller
+==================================
+
+This device follows the generic DMA bindings defined in dma/dma.txt.
+
+Required properties:
+
+- compatible: Must be one of
+ "fsl,ls1021a-qdma": for LS1021A Board
+ "fsl,ls1043a-qdma": for ls1043A Board
+ "fsl,ls1046a-qdma": for ls1046A Board
+- reg: Should contain the register's base address and length.
+- interrupts: Should contain a reference to the interrupt used by this
+ device.
+- interrupt-names: Should contain interrupt names:
+ "qdma-queue0": the block0 interrupt
+ "qdma-queue1": the block1 interrupt
+ "qdma-queue2": the block2 interrupt
+ "qdma-queue3": the block3 interrupt
+ "qdma-error": the error interrupt
+- fsl,dma-queues: Should contain number of queues supported.
+- dma-channels: Number of DMA channels supported
+- block-number: the virtual block number
+- block-offset: the offset of different virtual block
+- status-sizes: status queue size of per virtual block
+- queue-sizes: command queue size of per virtual block, the size number
+ based on queues
+
+Optional properties:
+
+- dma-channels: Number of DMA channels supported by the controller.
+- big-endian: If present registers and hardware scatter/gather descriptors
+ of the qDMA are implemented in big endian mode, otherwise in little
+ mode.
+
+Examples:
+
+ qdma: dma-controller@8390000 {
+ compatible = "fsl,ls1021a-qdma";
+ reg = <0x0 0x8388000 0x0 0x1000>, /* Controller regs */
+ <0x0 0x8389000 0x0 0x1000>, /* Status regs */
+ <0x0 0x838a000 0x0 0x2000>; /* Block regs */
+ interrupts = <GIC_SPI 185 IRQ_TYPE_LEVEL_HIGH>,
+ <GIC_SPI 76 IRQ_TYPE_LEVEL_HIGH>,
+ <GIC_SPI 77 IRQ_TYPE_LEVEL_HIGH>;
+ interrupt-names = "qdma-error",
+ "qdma-queue0", "qdma-queue1";
+ dma-channels = <8>;
+ block-number = <2>;
+ block-offset = <0x1000>;
+ fsl,dma-queues = <2>;
+ status-sizes = <64>;
+ queue-sizes = <64 64>;
+ big-endian;
+ };
+
+DMA clients must use the format described in dma/dma.txt file.
diff --git a/Documentation/devicetree/bindings/dma/k3dma.txt b/Documentation/devicetree/bindings/dma/k3dma.txt
index 4945aeac4dc4..10a2f15b08a3 100644
--- a/Documentation/devicetree/bindings/dma/k3dma.txt
+++ b/Documentation/devicetree/bindings/dma/k3dma.txt
@@ -3,7 +3,9 @@
See dma.txt first
Required properties:
-- compatible: Should be "hisilicon,k3-dma-1.0"
+- compatible: Must be one of
+- "hisilicon,k3-dma-1.0"
+- "hisilicon,hisi-pcm-asp-dma-1.0"
- reg: Should contain DMA registers location and length.
- interrupts: Should contain one interrupt shared by all channel
- #dma-cells: see dma.txt, should be 1, para number
diff --git a/Documentation/devicetree/bindings/dma/snps-dma.txt b/Documentation/devicetree/bindings/dma/snps-dma.txt
index db757df7057d..0bedceed1963 100644
--- a/Documentation/devicetree/bindings/dma/snps-dma.txt
+++ b/Documentation/devicetree/bindings/dma/snps-dma.txt
@@ -23,8 +23,6 @@ Deprecated properties:
Optional properties:
-- is_private: The device channels should be marked as private and not for by the
- general purpose DMA channel allocator. False if not passed.
- multi-block: Multi block transfers supported by hardware. Array property with
one cell per channel. 0: not supported, 1 (default): supported.
- snps,dma-protection-control: AHB HPROT[3:1] protection setting.
diff --git a/Documentation/devicetree/bindings/dma/sprd-dma.txt b/Documentation/devicetree/bindings/dma/sprd-dma.txt
index 7a10fea2e51b..adccea9941f1 100644
--- a/Documentation/devicetree/bindings/dma/sprd-dma.txt
+++ b/Documentation/devicetree/bindings/dma/sprd-dma.txt
@@ -31,7 +31,7 @@ DMA clients connected to the Spreadtrum DMA controller must use the format
described in the dma.txt file, using a two-cell specifier for each channel.
The two cells in order are:
1. A phandle pointing to the DMA controller.
-2. The channel id.
+2. The slave id.
spi0: spi@70a00000{
...
diff --git a/Documentation/devicetree/bindings/dma/xilinx/xilinx_dma.txt b/Documentation/devicetree/bindings/dma/xilinx/xilinx_dma.txt
index 174af2c45e77..93b6d961dd4f 100644
--- a/Documentation/devicetree/bindings/dma/xilinx/xilinx_dma.txt
+++ b/Documentation/devicetree/bindings/dma/xilinx/xilinx_dma.txt
@@ -37,10 +37,11 @@ Required properties:
Required properties for VDMA:
- xlnx,num-fstores: Should be the number of framebuffers as configured in h/w.
-Optional properties:
-- xlnx,include-sg: Tells configured for Scatter-mode in
- the hardware.
Optional properties for AXI DMA:
+- xlnx,sg-length-width: Should be set to the width in bits of the length
+ register as configured in h/w. Takes values {8...26}. If the property
+ is missing or invalid then the default value 23 is used. This is the
+ maximum value that is supported by all IP versions.
- xlnx,mcdma: Tells whether configured for multi-channel mode in the hardware.
Optional properties for VDMA:
- xlnx,flush-fsync: Tells which channel to Flush on Frame sync.
diff --git a/Documentation/devicetree/bindings/net/dsa/dsa.txt b/Documentation/devicetree/bindings/net/dsa/dsa.txt
index 35694c0c376b..d66a5292b9d3 100644
--- a/Documentation/devicetree/bindings/net/dsa/dsa.txt
+++ b/Documentation/devicetree/bindings/net/dsa/dsa.txt
@@ -71,6 +71,10 @@ properties, described in binding documents:
Documentation/devicetree/bindings/net/fixed-link.txt
for details.
+- local-mac-address : See
+ Documentation/devicetree/bindings/net/ethernet.txt
+ for details.
+
Example
The following example shows three switches on three MDIO busses,
@@ -97,6 +101,7 @@ linked into one DSA cluster.
port@1 {
reg = <1>;
label = "lan1";
+ local-mac-address = [00 00 00 00 00 00];
};
port@2 {
diff --git a/Documentation/devicetree/bindings/remoteproc/qcom,adsp-pil.txt b/Documentation/devicetree/bindings/remoteproc/qcom,adsp-pil.txt
index a842a782b557..66af2c30944f 100644
--- a/Documentation/devicetree/bindings/remoteproc/qcom,adsp-pil.txt
+++ b/Documentation/devicetree/bindings/remoteproc/qcom,adsp-pil.txt
@@ -35,7 +35,7 @@ on the Qualcomm Technology Inc. ADSP Hexagon core.
Value type: <stringlist>
Definition: List of clock input name strings sorted in the same
order as the clocks property. Definition must have
- "xo", "sway_cbcr", "lpass_aon", "lpass_ahbs_aon_cbcr",
+ "xo", "sway_cbcr", "lpass_ahbs_aon_cbcr",
"lpass_ahbm_aon_cbcr", "qdsp6ss_xo", "qdsp6ss_sleep"
and "qdsp6ss_core".
@@ -100,13 +100,12 @@ ADSP, as it is found on SDM845 boards.
clocks = <&rpmhcc RPMH_CXO_CLK>,
<&gcc GCC_LPASS_SWAY_CLK>,
- <&lpasscc LPASS_AUDIO_WRAPPER_AON_CLK>,
<&lpasscc LPASS_Q6SS_AHBS_AON_CLK>,
<&lpasscc LPASS_Q6SS_AHBM_AON_CLK>,
<&lpasscc LPASS_QDSP6SS_XO_CLK>,
<&lpasscc LPASS_QDSP6SS_SLEEP_CLK>,
<&lpasscc LPASS_QDSP6SS_CORE_CLK>;
- clock-names = "xo", "sway_cbcr", "lpass_aon",
+ clock-names = "xo", "sway_cbcr",
"lpass_ahbs_aon_cbcr",
"lpass_ahbm_aon_cbcr", "qdsp6ss_xo",
"qdsp6ss_sleep", "qdsp6ss_core";
diff --git a/Documentation/devicetree/bindings/remoteproc/qcom,adsp.txt b/Documentation/devicetree/bindings/remoteproc/qcom,adsp.txt
index 9c0cff3a5ed8..292dfda9770d 100644
--- a/Documentation/devicetree/bindings/remoteproc/qcom,adsp.txt
+++ b/Documentation/devicetree/bindings/remoteproc/qcom,adsp.txt
@@ -19,13 +19,30 @@ on the Qualcomm ADSP Hexagon core.
- interrupts-extended:
Usage: required
Value type: <prop-encoded-array>
- Definition: must list the watchdog, fatal IRQs ready, handover and
- stop-ack IRQs
+ Definition: reference to the interrupts that match interrupt-names
- interrupt-names:
Usage: required
Value type: <stringlist>
- Definition: must be "wdog", "fatal", "ready", "handover", "stop-ack"
+ Definition: The interrupts needed depends on the compatible
+ string:
+ qcom,msm8974-adsp-pil:
+ qcom,msm8996-adsp-pil:
+ qcom,msm8996-slpi-pil:
+ qcom,qcs404-adsp-pas:
+ qcom,qcs404-cdsp-pas:
+ qcom,sdm845-adsp-pas:
+ qcom,sdm845-cdsp-pas:
+ must be "wdog", "fatal", "ready", "handover", "stop-ack"
+ qcom,qcs404-wcss-pas:
+ must be "wdog", "fatal", "ready", "handover", "stop-ack",
+ "shutdown-ack"
+
+- firmware-name:
+ Usage: optional
+ Value type: <string>
+ Definition: must list the relative firmware image path for the
+ Hexagon Core.
- clocks:
Usage: required
diff --git a/Documentation/devicetree/bindings/remoteproc/qcom,q6v5.txt b/Documentation/devicetree/bindings/remoteproc/qcom,q6v5.txt
index 9ff5b0309417..41ca5df5be5a 100644
--- a/Documentation/devicetree/bindings/remoteproc/qcom,q6v5.txt
+++ b/Documentation/devicetree/bindings/remoteproc/qcom,q6v5.txt
@@ -28,24 +28,51 @@ on the Qualcomm Hexagon core.
- interrupts-extended:
Usage: required
Value type: <prop-encoded-array>
- Definition: must list the watchdog, fatal IRQs ready, handover and
- stop-ack IRQs
+ Definition: reference to the interrupts that match interrupt-names
- interrupt-names:
Usage: required
Value type: <stringlist>
- Definition: must be "wdog", "fatal", "ready", "handover", "stop-ack"
+ Definition: The interrupts needed depends on the the compatible
+ string:
+ qcom,q6v5-pil:
+ qcom,ipq8074-wcss-pil:
+ qcom,msm8916-mss-pil:
+ qcom,msm8974-mss-pil:
+ must be "wdog", "fatal", "ready", "handover", "stop-ack"
+ qcom,msm8996-mss-pil:
+ qcom,sdm845-mss-pil:
+ must be "wdog", "fatal", "ready", "handover", "stop-ack",
+ "shutdown-ack"
+
+- firmware-name:
+ Usage: optional
+ Value type: <stringlist>
+ Definition: must list the relative firmware image paths for mba and
+ modem. They are used for booting and authenticating the
+ Hexagon core.
- clocks:
Usage: required
Value type: <phandle>
- Definition: reference to the iface, bus and mem clocks to be held on
- behalf of the booting of the Hexagon core
+ Definition: reference to the clocks that match clock-names
- clock-names:
Usage: required
Value type: <stringlist>
- Definition: must be "iface", "bus", "mem"
+ Definition: The clocks needed depend on the compatible string:
+ qcom,ipq8074-wcss-pil:
+ no clock names required
+ qcom,q6v5-pil:
+ qcom,msm8916-mss-pil:
+ qcom,msm8974-mss-pil:
+ must be "iface", "bus", "mem", "xo"
+ qcom,msm8996-mss-pil:
+ must be "iface", "bus", "mem", "xo", "gpll0_mss",
+ "snoc_axi", "mnoc_axi", "pnoc", "qdss"
+ qcom,sdm845-mss-pil:
+ must be "iface", "bus", "mem", "xo", "gpll0_mss",
+ "snoc_axi", "mnoc_axi", "prng"
- resets:
Usage: required
@@ -65,6 +92,19 @@ on the Qualcomm Hexagon core.
must be "mss_restart", "pdc_reset" for the modem
sub-system on SDM845 SoCs
+For the compatible strings below the following supplies are required:
+ "qcom,q6v5-pil"
+ "qcom,msm8916-mss-pil",
+- cx-supply:
+- mx-supply:
+- pll-supply:
+ Usage: required
+ Value type: <phandle>
+ Definition: reference to the regulators to be held on behalf of the
+ booting of the Hexagon core
+
+For the compatible string below the following supplies are required:
+ "qcom,msm8974-mss-pil"
- cx-supply:
- mss-supply:
- mx-supply:
@@ -74,6 +114,33 @@ on the Qualcomm Hexagon core.
Definition: reference to the regulators to be held on behalf of the
booting of the Hexagon core
+For the compatible string below the following supplies are required:
+ "qcom,msm8996-mss-pil"
+- pll-supply:
+ Usage: required
+ Value type: <phandle>
+ Definition: reference to the regulators to be held on behalf of the
+ booting of the Hexagon core
+
+- power-domains:
+ Usage: required
+ Value type: <phandle>
+ Definition: reference to power-domains that match power-domain-names
+
+- power-domain-names:
+ Usage: required
+ Value type: <stringlist>
+ Definition: The power-domains needed depend on the compatible string:
+ qcom,q6v5-pil:
+ qcom,ipq8074-wcss-pil:
+ qcom,msm8916-mss-pil:
+ qcom,msm8974-mss-pil:
+ no power-domain names required
+ qcom,msm8996-mss-pil:
+ must be "cx", "mx"
+ qcom,sdm845-mss-pil:
+ must be "cx", "mx", "mss", "load_state"
+
- qcom,smem-states:
Usage: required
Value type: <phandle>
diff --git a/Documentation/driver-api/dmaengine/client.rst b/Documentation/driver-api/dmaengine/client.rst
index d728e50105eb..45953f171500 100644
--- a/Documentation/driver-api/dmaengine/client.rst
+++ b/Documentation/driver-api/dmaengine/client.rst
@@ -172,7 +172,7 @@ The details of these operations are:
After calling ``dmaengine_submit()`` the submitted transfer descriptor
(``struct dma_async_tx_descriptor``) belongs to the DMA engine.
- Consequentially, the client must consider invalid the pointer to that
+ Consequently, the client must consider invalid the pointer to that
descriptor.
5. Issue pending DMA requests and wait for callback notification
diff --git a/Documentation/driver-api/dmaengine/dmatest.rst b/Documentation/driver-api/dmaengine/dmatest.rst
index 8d81f1a7169b..e78d070bb468 100644
--- a/Documentation/driver-api/dmaengine/dmatest.rst
+++ b/Documentation/driver-api/dmaengine/dmatest.rst
@@ -59,6 +59,7 @@ parameter, that specific channel is requested using the dmaengine and a thread
is created with the existing parameters. This thread is set as pending
and will be executed once run is set to 1. Any parameters set after the thread
is created are not applied.
+
.. hint::
available channel list could be extracted by running the following command::
diff --git a/Documentation/driver-model/devres.txt b/Documentation/driver-model/devres.txt
index b277cafce71e..d7d6f01e81ff 100644
--- a/Documentation/driver-model/devres.txt
+++ b/Documentation/driver-model/devres.txt
@@ -242,9 +242,11 @@ certainly invest a bit more effort into libata core layer).
CLOCK
devm_clk_get()
+ devm_clk_get_optional()
devm_clk_put()
devm_clk_hw_register()
devm_of_clk_add_hw_provider()
+ devm_clk_hw_register_clkdev()
DMA
dmaenginem_async_device_register()
diff --git a/Documentation/filesystems/cifs/TODO b/Documentation/filesystems/cifs/TODO
index 66b3f54aa6dc..9267f3fb131f 100644
--- a/Documentation/filesystems/cifs/TODO
+++ b/Documentation/filesystems/cifs/TODO
@@ -111,7 +111,8 @@ negotiated size) and send larger write sizes to modern servers.
5) Continue to extend the smb3 "buildbot" which does automated xfstesting
against Windows, Samba and Azure currently - to add additional tests and
-to allow the buildbot to execute the tests faster.
+to allow the buildbot to execute the tests faster. The URL for the
+buildbot is: http://smb3-test-rhel-75.southcentralus.cloudapp.azure.com
6) Address various coverity warnings (most are not bugs per-se, but
the more warnings are addressed, the easier it is to spot real
diff --git a/Documentation/filesystems/cifs/cifs.txt b/Documentation/filesystems/cifs/cifs.txt
index 67756607246e..1be3d21c286e 100644
--- a/Documentation/filesystems/cifs/cifs.txt
+++ b/Documentation/filesystems/cifs/cifs.txt
@@ -1,16 +1,21 @@
This is the client VFS module for the SMB3 NAS protocol as well
- older dialects such as the Common Internet File System (CIFS)
+ as for older dialects such as the Common Internet File System (CIFS)
protocol which was the successor to the Server Message Block
(SMB) protocol, the native file sharing mechanism for most early
PC operating systems. New and improved versions of CIFS are now
- called SMB2 and SMB3. These dialects are also supported by the
- CIFS VFS module. CIFS is fully supported by network
- file servers such as Windows 2000, 2003, 2008, 2012 and 2016
- as well by Samba (which provides excellent CIFS
- server support for Linux and many other operating systems), Apple
- systems, as well as most Network Attached Storage vendors, so
- this network filesystem client can mount to a wide variety of
- servers.
+ called SMB2 and SMB3. Use of SMB3 (and later, including SMB3.1.1)
+ is strongly preferred over using older dialects like CIFS due to
+ security reaasons. All modern dialects, including the most recent,
+ SMB3.1.1 are supported by the CIFS VFS module. The SMB3 protocol
+ is implemented and supported by all major file servers
+ such as all modern versions of Windows (including Windows 2016
+ Server), as well as by Samba (which provides excellent
+ CIFS/SMB2/SMB3 server support and tools for Linux and many other
+ operating systems). Apple systems also support SMB3 well, as
+ do most Network Attached Storage vendors, so this network
+ filesystem client can mount to a wide variety of systems.
+ It also supports mounting to the cloud (for example
+ Microsoft Azure), including the necessary security features.
The intent of this module is to provide the most advanced network
file system function for SMB3 compliant servers, including advanced
@@ -24,12 +29,17 @@
cluster file systems for fileserving in some Linux to Linux environments,
not just in Linux to Windows (or Linux to Mac) environments.
- This filesystem has an mount utility (mount.cifs) that can be obtained from
+ This filesystem has a mount utility (mount.cifs) and various user space
+ tools (including smbinfo and setcifsacl) that can be obtained from
- https://ftp.samba.org/pub/linux-cifs/cifs-utils/
+ https://git.samba.org/?p=cifs-utils.git
+ or
+ git://git.samba.org/cifs-utils.git
- It must be installed in the directory with the other mount helpers.
+ mount.cifs should be installed in the directory with the other mount helpers.
For more information on the module see the project wiki page at
+ https://wiki.samba.org/index.php/LinuxCIFS
+ and
https://wiki.samba.org/index.php/LinuxCIFS_utils
diff --git a/Documentation/filesystems/f2fs.txt b/Documentation/filesystems/f2fs.txt
index e46c2147ddf8..f7b5e4ff0de3 100644
--- a/Documentation/filesystems/f2fs.txt
+++ b/Documentation/filesystems/f2fs.txt
@@ -126,6 +126,8 @@ disable_ext_identify Disable the extension list configured by mkfs, so f2fs
does not aware of cold files such as media files.
inline_xattr Enable the inline xattrs feature.
noinline_xattr Disable the inline xattrs feature.
+inline_xattr_size=%u Support configuring inline xattr size, it depends on
+ flexible inline xattr feature.
inline_data Enable the inline data feature: New created small(<~3.4k)
files can be written into inode block.
inline_dentry Enable the inline dir feature: data in new created
diff --git a/Documentation/virtual/kvm/api.txt b/Documentation/virtual/kvm/api.txt
index 356156f5c52d..7de9eee73fcd 100644
--- a/Documentation/virtual/kvm/api.txt
+++ b/Documentation/virtual/kvm/api.txt
@@ -45,6 +45,23 @@ the API. The only supported use is one virtual machine per process,
and one vcpu per thread.
+It is important to note that althought VM ioctls may only be issued from
+the process that created the VM, a VM's lifecycle is associated with its
+file descriptor, not its creator (process). In other words, the VM and
+its resources, *including the associated address space*, are not freed
+until the last reference to the VM's file descriptor has been released.
+For example, if fork() is issued after ioctl(KVM_CREATE_VM), the VM will
+not be freed until both the parent (original) process and its child have
+put their references to the VM's file descriptor.
+
+Because a VM's resources are not freed until the last reference to its
+file descriptor is released, creating additional references to a VM via
+via fork(), dup(), etc... without careful consideration is strongly
+discouraged and may have unwanted side effects, e.g. memory allocated
+by and on behalf of the VM's process may not be freed/unaccounted when
+the VM is shut down.
+
+
3. Extensions
-------------
diff --git a/Documentation/virtual/kvm/halt-polling.txt b/Documentation/virtual/kvm/halt-polling.txt
index 4a8418318769..4f791b128dd2 100644
--- a/Documentation/virtual/kvm/halt-polling.txt
+++ b/Documentation/virtual/kvm/halt-polling.txt
@@ -53,7 +53,8 @@ the global max polling interval then the polling interval can be increased in
the hope that next time during the longer polling interval the wake up source
will be received while the host is polling and the latency benefits will be
received. The polling interval is grown in the function grow_halt_poll_ns() and
-is multiplied by the module parameter halt_poll_ns_grow.
+is multiplied by the module parameters halt_poll_ns_grow and
+halt_poll_ns_grow_start.
In the event that the total block time was greater than the global max polling
interval then the host will never poll for long enough (limited by the global
@@ -80,22 +81,30 @@ shrunk. These variables are defined in include/linux/kvm_host.h and as module
parameters in virt/kvm/kvm_main.c, or arch/powerpc/kvm/book3s_hv.c in the
powerpc kvm-hv case.
-Module Parameter | Description | Default Value
+Module Parameter | Description | Default Value
--------------------------------------------------------------------------------
-halt_poll_ns | The global max polling interval | KVM_HALT_POLL_NS_DEFAULT
- | which defines the ceiling value |
- | of the polling interval for | (per arch value)
- | each vcpu. |
+halt_poll_ns | The global max polling | KVM_HALT_POLL_NS_DEFAULT
+ | interval which defines |
+ | the ceiling value of the |
+ | polling interval for | (per arch value)
+ | each vcpu. |
--------------------------------------------------------------------------------
-halt_poll_ns_grow | The value by which the halt | 2
- | polling interval is multiplied |
- | in the grow_halt_poll_ns() |
- | function. |
+halt_poll_ns_grow | The value by which the | 2
+ | halt polling interval is |
+ | multiplied in the |
+ | grow_halt_poll_ns() |
+ | function. |
--------------------------------------------------------------------------------
-halt_poll_ns_shrink | The value by which the halt | 0
- | polling interval is divided in |
- | the shrink_halt_poll_ns() |
- | function. |
+halt_poll_ns_grow_start | The initial value to grow | 10000
+ | to from zero in the |
+ | grow_halt_poll_ns() |
+ | function. |
+--------------------------------------------------------------------------------
+halt_poll_ns_shrink | The value by which the | 0
+ | halt polling interval is |
+ | divided in the |
+ | shrink_halt_poll_ns() |
+ | function. |
--------------------------------------------------------------------------------
These module parameters can be set from the debugfs files in:
diff --git a/Documentation/virtual/kvm/mmu.txt b/Documentation/virtual/kvm/mmu.txt
index e507a9e0421e..f365102c80f5 100644
--- a/Documentation/virtual/kvm/mmu.txt
+++ b/Documentation/virtual/kvm/mmu.txt
@@ -224,10 +224,6 @@ Shadow pages contain the following information:
A bitmap indicating which sptes in spt point (directly or indirectly) at
pages that may be unsynchronized. Used to quickly locate all unsychronized
pages reachable from a given page.
- mmu_valid_gen:
- Generation number of the page. It is compared with kvm->arch.mmu_valid_gen
- during hash table lookup, and used to skip invalidated shadow pages (see
- "Zapping all pages" below.)
clear_spte_count:
Only present on 32-bit hosts, where a 64-bit spte cannot be written
atomically. The reader uses this while running out of the MMU lock
@@ -402,27 +398,6 @@ causes its disallow_lpage to be incremented, thus preventing instantiation of
a large spte. The frames at the end of an unaligned memory slot have
artificially inflated ->disallow_lpages so they can never be instantiated.
-Zapping all pages (page generation count)
-=========================================
-
-For the large memory guests, walking and zapping all pages is really slow
-(because there are a lot of pages), and also blocks memory accesses of
-all VCPUs because it needs to hold the MMU lock.
-
-To make it be more scalable, kvm maintains a global generation number
-which is stored in kvm->arch.mmu_valid_gen. Every shadow page stores
-the current global generation-number into sp->mmu_valid_gen when it
-is created. Pages with a mismatching generation number are "obsolete".
-
-When KVM need zap all shadow pages sptes, it just simply increases the global
-generation-number then reload root shadow pages on all vcpus. As the VCPUs
-create new shadow page tables, the old pages are not used because of the
-mismatching generation number.
-
-KVM then walks through all pages and zaps obsolete pages. While the zap
-operation needs to take the MMU lock, the lock can be released periodically
-so that the VCPUs can make progress.
-
Fast invalidation of MMIO sptes
===============================
@@ -435,8 +410,7 @@ shadow pages, and is made more scalable with a similar technique.
MMIO sptes have a few spare bits, which are used to store a
generation number. The global generation number is stored in
kvm_memslots(kvm)->generation, and increased whenever guest memory info
-changes. This generation number is distinct from the one described in
-the previous section.
+changes.
When KVM finds an MMIO spte, it checks the generation number of the spte.
If the generation number of the spte does not equal the global generation
@@ -452,13 +426,16 @@ stored into the MMIO spte. Thus, the MMIO spte might be created based on
out-of-date information, but with an up-to-date generation number.
To avoid this, the generation number is incremented again after synchronize_srcu
-returns; thus, the low bit of kvm_memslots(kvm)->generation is only 1 during a
+returns; thus, bit 63 of kvm_memslots(kvm)->generation set to 1 only during a
memslot update, while some SRCU readers might be using the old copy. We do not
want to use an MMIO sptes created with an odd generation number, and we can do
-this without losing a bit in the MMIO spte. The low bit of the generation
-is not stored in MMIO spte, and presumed zero when it is extracted out of the
-spte. If KVM is unlucky and creates an MMIO spte while the low bit is 1,
-the next access to the spte will always be a cache miss.
+this without losing a bit in the MMIO spte. The "update in-progress" bit of the
+generation is not stored in MMIO spte, and is so is implicitly zero when the
+generation is extracted out of the spte. If KVM is unlucky and creates an MMIO
+spte while an update is in-progress, the next access to the spte will always be
+a cache miss. For example, a subsequent access during the update window will
+miss due to the in-progress flag diverging, while an access after the update
+window closes will have a higher generation number (as compared to the spte).
Further reading