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| author | Miguel Ojeda <ojeda@kernel.org> | 2026-04-08 09:46:01 +0200 |
|---|---|---|
| committer | Miguel Ojeda <ojeda@kernel.org> | 2026-04-08 10:44:11 +0200 |
| commit | b06b348e855383ed80e041299f3925cdd7dff3da (patch) | |
| tree | 711ca958418fe1b8253929f163fc4b279498111a /Documentation | |
| parent | f4231eb25cd215882d4a5da9110d3772c2644b6c (diff) | |
| parent | ddb1444d3335129ae87d9796ab1debf41c0ee51b (diff) | |
| download | linux-next-b06b348e855383ed80e041299f3925cdd7dff3da.tar.gz linux-next-b06b348e855383ed80e041299f3925cdd7dff3da.zip | |
Merge tag 'rust-timekeeping-for-v7.1' of https://github.com/Rust-for-Linux/linux into rust-next
Pull timekeeping updates from Andreas Hindborg:
- Expand the example section in the 'HrTimer' documentation.
- Mark the 'ClockSource' trait as unsafe to ensure valid values for
'ktime_get()'.
- Add 'Delta::from_nanos()'.
This is a back merge since the pull request has a newer base -- we will
avoid that in the future.
And, given it is a back merge, it happens to resolve the "subtle" conflict
around '--remap-path-{prefix,scope}' that I discussed in linux-next [1],
plus a few other common conflicts. The result matches what we did for
next-20260407.
The actual diffstat (i.e. using a temporary merge of upstream first) is:
rust/kernel/time.rs | 32 ++++-
rust/kernel/time/hrtimer.rs | 336 ++++++++++++++++++++++++++++++++++++++++++++
2 files changed, 362 insertions(+), 6 deletions(-)
Link: https://lore.kernel.org/linux-next/CANiq72kdxB=W3_CV1U44oOK3SssztPo2wLDZt6LP94TEO+Kj4g@mail.gmail.com/ [1]
* tag 'rust-timekeeping-for-v7.1' of https://github.com/Rust-for-Linux/linux:
hrtimer: add usage examples to documentation
rust: time: make ClockSource unsafe trait
rust/time: Add Delta::from_nanos()
Diffstat (limited to 'Documentation')
17 files changed, 380 insertions, 146 deletions
diff --git a/Documentation/ABI/testing/sysfs-block-zram b/Documentation/ABI/testing/sysfs-block-zram index e538d4850d61..64c03010e951 100644 --- a/Documentation/ABI/testing/sysfs-block-zram +++ b/Documentation/ABI/testing/sysfs-block-zram @@ -151,11 +151,11 @@ Description: The algorithm_params file is write-only and is used to setup compression algorithm parameters. -What: /sys/block/zram<id>/writeback_compressed +What: /sys/block/zram<id>/compressed_writeback Date: Decemeber 2025 Contact: Richard Chang <richardycc@google.com> Description: - The writeback_compressed device atrribute toggles compressed + The compressed_writeback device atrribute toggles compressed writeback feature. What: /sys/block/zram<id>/writeback_batch_size diff --git a/Documentation/admin-guide/blockdev/zram.rst b/Documentation/admin-guide/blockdev/zram.rst index 94bb7f2245ee..451fa00d3004 100644 --- a/Documentation/admin-guide/blockdev/zram.rst +++ b/Documentation/admin-guide/blockdev/zram.rst @@ -216,7 +216,7 @@ writeback_limit WO specifies the maximum amount of write IO zram writeback_limit_enable RW show and set writeback_limit feature writeback_batch_size RW show and set maximum number of in-flight writeback operations -writeback_compressed RW show and set compressed writeback feature +compressed_writeback RW show and set compressed writeback feature comp_algorithm RW show and change the compression algorithm algorithm_params WO setup compression algorithm parameters compact WO trigger memory compaction @@ -439,11 +439,11 @@ budget in next setting is user's job. By default zram stores written back pages in decompressed (raw) form, which means that writeback operation involves decompression of the page before writing it to the backing device. This behavior can be changed by enabling -`writeback_compressed` feature, which causes zram to write compressed pages +`compressed_writeback` feature, which causes zram to write compressed pages to the backing device, thus avoiding decompression overhead. To enable this feature, execute:: - $ echo yes > /sys/block/zramX/writeback_compressed + $ echo yes > /sys/block/zramX/compressed_writeback Note that this feature should be configured before the `zramX` device is initialized. diff --git a/Documentation/admin-guide/kernel-parameters.txt b/Documentation/admin-guide/kernel-parameters.txt index 55ffc0f8858a..03a550630644 100644 --- a/Documentation/admin-guide/kernel-parameters.txt +++ b/Documentation/admin-guide/kernel-parameters.txt @@ -8196,6 +8196,9 @@ Kernel parameters p = USB_QUIRK_SHORT_SET_ADDRESS_REQ_TIMEOUT (Reduce timeout of the SET_ADDRESS request from 5000 ms to 500 ms); + q = USB_QUIRK_FORCE_ONE_CONFIG (Device + claims zero configurations, + forcing to 1); Example: quirks=0781:5580:bk,0a5c:5834:gij usbhid.mousepoll= diff --git a/Documentation/dev-tools/kunit/run_wrapper.rst b/Documentation/dev-tools/kunit/run_wrapper.rst index 3c0b585dcfff..770bb09a475a 100644 --- a/Documentation/dev-tools/kunit/run_wrapper.rst +++ b/Documentation/dev-tools/kunit/run_wrapper.rst @@ -336,6 +336,8 @@ command line arguments: - ``--list_tests_attr``: If set, lists all tests that will be run and all of their attributes. +- ``--list_suites``: If set, lists all suites that will be run. + Command-line completion ============================== diff --git a/Documentation/devicetree/bindings/display/msm/dp-controller.yaml b/Documentation/devicetree/bindings/display/msm/dp-controller.yaml index ebda78db87a6..02ddfaab5f56 100644 --- a/Documentation/devicetree/bindings/display/msm/dp-controller.yaml +++ b/Documentation/devicetree/bindings/display/msm/dp-controller.yaml @@ -253,7 +253,6 @@ allOf: enum: # these platforms support 2 streams MST on some interfaces, # others are SST only - - qcom,glymur-dp - qcom,sc8280xp-dp - qcom,x1e80100-dp then: @@ -310,6 +309,26 @@ allOf: minItems: 6 maxItems: 8 + - if: + properties: + compatible: + contains: + enum: + # these platforms support 2 streams MST on some interfaces, + # others are SST only, but all controllers have 4 ports + - qcom,glymur-dp + then: + properties: + reg: + minItems: 9 + maxItems: 9 + clocks: + minItems: 5 + maxItems: 6 + clocks-names: + minItems: 5 + maxItems: 6 + unevaluatedProperties: false examples: diff --git a/Documentation/devicetree/bindings/display/msm/qcom,glymur-mdss.yaml b/Documentation/devicetree/bindings/display/msm/qcom,glymur-mdss.yaml index 2329ed96e6cb..64dde43373ac 100644 --- a/Documentation/devicetree/bindings/display/msm/qcom,glymur-mdss.yaml +++ b/Documentation/devicetree/bindings/display/msm/qcom,glymur-mdss.yaml @@ -176,13 +176,17 @@ examples: }; }; - displayport-controller@ae90000 { + displayport-controller@af54000 { compatible = "qcom,glymur-dp"; - reg = <0xae90000 0x200>, - <0xae90200 0x200>, - <0xae90400 0x600>, - <0xae91000 0x400>, - <0xae91400 0x400>; + reg = <0xaf54000 0x200>, + <0xaf54200 0x200>, + <0xaf55000 0xc00>, + <0xaf56000 0x400>, + <0xaf57000 0x400>, + <0xaf58000 0x400>, + <0xaf59000 0x400>, + <0xaf5a000 0x600>, + <0xaf5b000 0x600>; interrupt-parent = <&mdss>; interrupts = <12>; diff --git a/Documentation/devicetree/bindings/display/msm/qcom,sm8750-mdss.yaml b/Documentation/devicetree/bindings/display/msm/qcom,sm8750-mdss.yaml index d55fda9a523e..a38c2261ef1a 100644 --- a/Documentation/devicetree/bindings/display/msm/qcom,sm8750-mdss.yaml +++ b/Documentation/devicetree/bindings/display/msm/qcom,sm8750-mdss.yaml @@ -10,7 +10,7 @@ maintainers: - Krzysztof Kozlowski <krzk@kernel.org> description: - SM8650 MSM Mobile Display Subsystem(MDSS), which encapsulates sub-blocks like + SM8750 MSM Mobile Display Subsystem(MDSS), which encapsulates sub-blocks like DPU display controller, DSI and DP interfaces etc. $ref: /schemas/display/msm/mdss-common.yaml# diff --git a/Documentation/devicetree/bindings/i2c/snps,designware-i2c.yaml b/Documentation/devicetree/bindings/i2c/snps,designware-i2c.yaml index 914200188809..082fdc2e69ea 100644 --- a/Documentation/devicetree/bindings/i2c/snps,designware-i2c.yaml +++ b/Documentation/devicetree/bindings/i2c/snps,designware-i2c.yaml @@ -7,7 +7,7 @@ $schema: http://devicetree.org/meta-schemas/core.yaml# title: Synopsys DesignWare APB I2C Controller maintainers: - - Jarkko Nikula <jarkko.nikula@linux.intel.com> + - Mika Westerberg <mika.westerberg@linux.intel.com> allOf: - $ref: /schemas/i2c/i2c-controller.yaml# diff --git a/Documentation/devicetree/bindings/mtd/st,spear600-smi.yaml b/Documentation/devicetree/bindings/mtd/st,spear600-smi.yaml index 8fe27aae7527..e7385d906591 100644 --- a/Documentation/devicetree/bindings/mtd/st,spear600-smi.yaml +++ b/Documentation/devicetree/bindings/mtd/st,spear600-smi.yaml @@ -19,9 +19,6 @@ description: Flash sub nodes describe the memory range and optional per-flash properties. -allOf: - - $ref: mtd.yaml# - properties: compatible: const: st,spear600-smi @@ -42,14 +39,29 @@ properties: $ref: /schemas/types.yaml#/definitions/uint32 description: Functional clock rate of the SMI controller in Hz. - st,smi-fast-mode: - type: boolean - description: Indicates that the attached flash supports fast read mode. +patternProperties: + "^flash@.*$": + $ref: /schemas/mtd/mtd.yaml# + + properties: + reg: + maxItems: 1 + + st,smi-fast-mode: + type: boolean + description: Indicates that the attached flash supports fast read mode. + + unevaluatedProperties: false + + required: + - reg required: - compatible - reg - clock-rate + - "#address-cells" + - "#size-cells" unevaluatedProperties: false @@ -64,7 +76,7 @@ examples: interrupts = <12>; clock-rate = <50000000>; /* 50 MHz */ - flash@f8000000 { + flash@fc000000 { reg = <0xfc000000 0x1000>; st,smi-fast-mode; }; diff --git a/Documentation/devicetree/bindings/powerpc/fsl/fsl,mpc83xx.yaml b/Documentation/devicetree/bindings/powerpc/fsl/fsl,mpc83xx.yaml new file mode 100644 index 000000000000..9e37d155c582 --- /dev/null +++ b/Documentation/devicetree/bindings/powerpc/fsl/fsl,mpc83xx.yaml @@ -0,0 +1,93 @@ +# SPDX-License-Identifier: (GPL-2.0-only OR BSD-2-Clause) +%YAML 1.2 +--- +$id: http://devicetree.org/schemas/powerpc/fsl/fsl,mpc83xx.yaml# +$schema: http://devicetree.org/meta-schemas/core.yaml# + +title: Freescale PowerQUICC II Pro (MPC83xx) platforms + +maintainers: + - J. Neuschäfer <j.ne@posteo.net> + +properties: + $nodename: + const: '/' + compatible: + oneOf: + - description: MPC83xx Reference Design Boards + items: + - enum: + - fsl,mpc8308rdb + - fsl,mpc8315erdb + - fsl,mpc8360rdk + - fsl,mpc8377rdb + - fsl,mpc8377wlan + - fsl,mpc8378rdb + - fsl,mpc8379rdb + + - description: MPC8313E Reference Design Board + items: + - const: MPC8313ERDB + - const: MPC831xRDB + - const: MPC83xxRDB + + - description: MPC8323E Reference Design Board + items: + - const: MPC8323ERDB + - const: MPC832xRDB + - const: MPC83xxRDB + + - description: MPC8349E-mITX(-GP) Reference Design Platform + items: + - enum: + - MPC8349EMITX + - MPC8349EMITXGP + - const: MPC834xMITX + - const: MPC83xxMITX + + - description: Keymile KMETER1 board + const: keymile,KMETER1 + + - description: MPC8308 P1M board + const: denx,mpc8308_p1m + +patternProperties: + "^soc@.*$": + type: object + properties: + compatible: + oneOf: + - items: + - enum: + - fsl,mpc8315-immr + - fsl,mpc8308-immr + - const: simple-bus + - items: + - const: fsl,mpc8360-immr + - const: fsl,immr + - const: fsl,soc + - const: simple-bus + - const: simple-bus + +additionalProperties: true + +examples: + - | + / { + compatible = "fsl,mpc8315erdb"; + model = "MPC8315E-RDB"; + #address-cells = <1>; + #size-cells = <1>; + + soc@e0000000 { + compatible = "fsl,mpc8315-immr", "simple-bus"; + reg = <0xe0000000 0x00000200>; + #address-cells = <1>; + #size-cells = <1>; + device_type = "soc"; + ranges = <0 0xe0000000 0x00100000>; + bus-frequency = <0>; + }; + }; + +... diff --git a/Documentation/devicetree/bindings/regulator/regulator.yaml b/Documentation/devicetree/bindings/regulator/regulator.yaml index 042e56396399..019aeb664cae 100644 --- a/Documentation/devicetree/bindings/regulator/regulator.yaml +++ b/Documentation/devicetree/bindings/regulator/regulator.yaml @@ -168,7 +168,7 @@ properties: offset from voltage set to regulator. regulator-uv-protection-microvolt: - description: Set over under voltage protection limit. This is a limit where + description: Set under voltage protection limit. This is a limit where hardware performs emergency shutdown. Zero can be passed to disable protection and value '1' indicates that protection should be enabled but limit setting can be omitted. Limit is given as microvolt offset from @@ -182,7 +182,7 @@ properties: is given as microvolt offset from voltage set to regulator. regulator-uv-warn-microvolt: - description: Set over under voltage warning limit. This is a limit where + description: Set under voltage warning limit. This is a limit where hardware is assumed still to be functional but approaching limit where it gets damaged. Recovery actions should be initiated. Zero can be passed to disable detection and value '1' indicates that detection should diff --git a/Documentation/devicetree/bindings/spi/allwinner,sun6i-a31-spi.yaml b/Documentation/devicetree/bindings/spi/allwinner,sun6i-a31-spi.yaml index a6067030c5ed..6af4ff233158 100644 --- a/Documentation/devicetree/bindings/spi/allwinner,sun6i-a31-spi.yaml +++ b/Documentation/devicetree/bindings/spi/allwinner,sun6i-a31-spi.yaml @@ -6,9 +6,6 @@ $schema: http://devicetree.org/meta-schemas/core.yaml# title: Allwinner A31 SPI Controller -allOf: - - $ref: spi-controller.yaml - maintainers: - Chen-Yu Tsai <wens@csie.org> - Maxime Ripard <mripard@kernel.org> @@ -82,11 +79,11 @@ patternProperties: spi-rx-bus-width: items: - - const: 1 + enum: [0, 1, 2, 4] spi-tx-bus-width: items: - - const: 1 + enum: [0, 1, 2, 4] required: - compatible @@ -95,6 +92,28 @@ required: - clocks - clock-names +allOf: + - $ref: spi-controller.yaml + - if: + not: + properties: + compatible: + contains: + enum: + - allwinner,sun50i-r329-spi + - allwinner,sun55i-a523-spi + then: + patternProperties: + "^.*@[0-9a-f]+": + properties: + spi-rx-bus-width: + items: + enum: [0, 1] + + spi-tx-bus-width: + items: + enum: [0, 1] + unevaluatedProperties: false examples: diff --git a/Documentation/driver-api/driver-model/binding.rst b/Documentation/driver-api/driver-model/binding.rst index d1d311a4011f..fa0888c2b3b9 100644 --- a/Documentation/driver-api/driver-model/binding.rst +++ b/Documentation/driver-api/driver-model/binding.rst @@ -99,3 +99,51 @@ of the driver is decremented. All symlinks between the two are removed. When a driver is removed, the list of devices that it supports is iterated over, and the driver's remove callback is called for each one. The device is removed from that list and the symlinks removed. + + +Driver Override +~~~~~~~~~~~~~~~ + +Userspace may override the standard matching by writing a driver name to +a device's ``driver_override`` sysfs attribute. When set, only a driver +whose name matches the override will be considered during binding. This +bypasses all bus-specific matching (OF, ACPI, ID tables, etc.). + +The override may be cleared by writing an empty string, which returns +the device to standard matching rules. Writing to ``driver_override`` +does not automatically unbind the device from its current driver or +make any attempt to load the specified driver. + +Buses opt into this mechanism by setting the ``driver_override`` flag in +their ``struct bus_type``:: + + const struct bus_type example_bus_type = { + ... + .driver_override = true, + }; + +When the flag is set, the driver core automatically creates the +``driver_override`` sysfs attribute for every device on that bus. + +The bus's ``match()`` callback should check the override before performing +its own matching, using ``device_match_driver_override()``:: + + static int example_match(struct device *dev, const struct device_driver *drv) + { + int ret; + + ret = device_match_driver_override(dev, drv); + if (ret >= 0) + return ret; + + /* Fall through to bus-specific matching... */ + } + +``device_match_driver_override()`` returns > 0 if the override matches +the given driver, 0 if the override is set but does not match, or < 0 if +no override is set at all. + +Additional helpers are available: + +- ``device_set_driver_override()`` - set or clear the override from kernel code. +- ``device_has_driver_override()`` - check whether an override is set. diff --git a/Documentation/netlink/specs/net_shaper.yaml b/Documentation/netlink/specs/net_shaper.yaml index 0b1b54be48f9..3f2ad772b64b 100644 --- a/Documentation/netlink/specs/net_shaper.yaml +++ b/Documentation/netlink/specs/net_shaper.yaml @@ -247,8 +247,8 @@ operations: flags: [admin-perm] do: - pre: net-shaper-nl-pre-doit - post: net-shaper-nl-post-doit + pre: net-shaper-nl-pre-doit-write + post: net-shaper-nl-post-doit-write request: attributes: - ifindex @@ -278,8 +278,8 @@ operations: flags: [admin-perm] do: - pre: net-shaper-nl-pre-doit - post: net-shaper-nl-post-doit + pre: net-shaper-nl-pre-doit-write + post: net-shaper-nl-post-doit-write request: attributes: *ns-binding @@ -309,8 +309,8 @@ operations: flags: [admin-perm] do: - pre: net-shaper-nl-pre-doit - post: net-shaper-nl-post-doit + pre: net-shaper-nl-pre-doit-write + post: net-shaper-nl-post-doit-write request: attributes: - ifindex diff --git a/Documentation/scheduler/sched-ext.rst b/Documentation/scheduler/sched-ext.rst index 9e2882d937b4..d74c2c2b9ef3 100644 --- a/Documentation/scheduler/sched-ext.rst +++ b/Documentation/scheduler/sched-ext.rst @@ -43,7 +43,6 @@ options should be enabled to use sched_ext: CONFIG_DEBUG_INFO_BTF=y CONFIG_BPF_JIT_ALWAYS_ON=y CONFIG_BPF_JIT_DEFAULT_ON=y - CONFIG_PAHOLE_HAS_BTF_TAG=y sched_ext is used only when the BPF scheduler is loaded and running. @@ -58,7 +57,8 @@ in ``ops->flags``, all ``SCHED_NORMAL``, ``SCHED_BATCH``, ``SCHED_IDLE``, and However, when the BPF scheduler is loaded and ``SCX_OPS_SWITCH_PARTIAL`` is set in ``ops->flags``, only tasks with the ``SCHED_EXT`` policy are scheduled by sched_ext, while tasks with ``SCHED_NORMAL``, ``SCHED_BATCH`` and -``SCHED_IDLE`` policies are scheduled by the fair-class scheduler. +``SCHED_IDLE`` policies are scheduled by the fair-class scheduler which has +higher sched_class precedence than ``SCHED_EXT``. Terminating the sched_ext scheduler program, triggering `SysRq-S`, or detection of any internal error including stalled runnable tasks aborts the @@ -345,6 +345,8 @@ Where to Look The functions prefixed with ``scx_bpf_`` can be called from the BPF scheduler. +* ``kernel/sched/ext_idle.c`` contains the built-in idle CPU selection policy. + * ``tools/sched_ext/`` hosts example BPF scheduler implementations. * ``scx_simple[.bpf].c``: Minimal global FIFO scheduler example using a @@ -353,13 +355,35 @@ Where to Look * ``scx_qmap[.bpf].c``: A multi-level FIFO scheduler supporting five levels of priority implemented with ``BPF_MAP_TYPE_QUEUE``. + * ``scx_central[.bpf].c``: A central FIFO scheduler where all scheduling + decisions are made on one CPU, demonstrating ``LOCAL_ON`` dispatching, + tickless operation, and kthread preemption. + + * ``scx_cpu0[.bpf].c``: A scheduler that queues all tasks to a shared DSQ + and only dispatches them on CPU0 in FIFO order. Useful for testing bypass + behavior. + + * ``scx_flatcg[.bpf].c``: A flattened cgroup hierarchy scheduler + implementing hierarchical weight-based cgroup CPU control by compounding + each cgroup's share at every level into a single flat scheduling layer. + + * ``scx_pair[.bpf].c``: A core-scheduling example that always makes + sibling CPU pairs execute tasks from the same CPU cgroup. + + * ``scx_sdt[.bpf].c``: A variation of ``scx_simple`` demonstrating BPF + arena memory management for per-task data. + + * ``scx_userland[.bpf].c``: A minimal scheduler demonstrating user space + scheduling. Tasks with CPU affinity are direct-dispatched in FIFO order; + all others are scheduled in user space by a simple vruntime scheduler. + ABI Instability =============== The APIs provided by sched_ext to BPF schedulers programs have no stability guarantees. This includes the ops table callbacks and constants defined in ``include/linux/sched/ext.h``, as well as the ``scx_bpf_`` kfuncs defined in -``kernel/sched/ext.c``. +``kernel/sched/ext.c`` and ``kernel/sched/ext_idle.c``. While we will attempt to provide a relatively stable API surface when possible, they are subject to change without warning between kernel diff --git a/Documentation/virt/kvm/api.rst b/Documentation/virt/kvm/api.rst index 6f85e1b321dd..032516783e96 100644 --- a/Documentation/virt/kvm/api.rst +++ b/Documentation/virt/kvm/api.rst @@ -8435,115 +8435,123 @@ KVM_CHECK_EXTENSION. The valid bits in cap.args[0] are: -=================================== ============================================ - KVM_X86_QUIRK_LINT0_REENABLED By default, the reset value for the LVT - LINT0 register is 0x700 (APIC_MODE_EXTINT). - When this quirk is disabled, the reset value - is 0x10000 (APIC_LVT_MASKED). - - KVM_X86_QUIRK_CD_NW_CLEARED By default, KVM clears CR0.CD and CR0.NW on - AMD CPUs to workaround buggy guest firmware - that runs in perpetuity with CR0.CD, i.e. - with caches in "no fill" mode. - - When this quirk is disabled, KVM does not - change the value of CR0.CD and CR0.NW. - - KVM_X86_QUIRK_LAPIC_MMIO_HOLE By default, the MMIO LAPIC interface is - available even when configured for x2APIC - mode. When this quirk is disabled, KVM - disables the MMIO LAPIC interface if the - LAPIC is in x2APIC mode. - - KVM_X86_QUIRK_OUT_7E_INC_RIP By default, KVM pre-increments %rip before - exiting to userspace for an OUT instruction - to port 0x7e. When this quirk is disabled, - KVM does not pre-increment %rip before - exiting to userspace. - - KVM_X86_QUIRK_MISC_ENABLE_NO_MWAIT When this quirk is disabled, KVM sets - CPUID.01H:ECX[bit 3] (MONITOR/MWAIT) if - IA32_MISC_ENABLE[bit 18] (MWAIT) is set. - Additionally, when this quirk is disabled, - KVM clears CPUID.01H:ECX[bit 3] if - IA32_MISC_ENABLE[bit 18] is cleared. - - KVM_X86_QUIRK_FIX_HYPERCALL_INSN By default, KVM rewrites guest - VMMCALL/VMCALL instructions to match the - vendor's hypercall instruction for the - system. When this quirk is disabled, KVM - will no longer rewrite invalid guest - hypercall instructions. Executing the - incorrect hypercall instruction will - generate a #UD within the guest. - -KVM_X86_QUIRK_MWAIT_NEVER_UD_FAULTS By default, KVM emulates MONITOR/MWAIT (if - they are intercepted) as NOPs regardless of - whether or not MONITOR/MWAIT are supported - according to guest CPUID. When this quirk - is disabled and KVM_X86_DISABLE_EXITS_MWAIT - is not set (MONITOR/MWAIT are intercepted), - KVM will inject a #UD on MONITOR/MWAIT if - they're unsupported per guest CPUID. Note, - KVM will modify MONITOR/MWAIT support in - guest CPUID on writes to MISC_ENABLE if - KVM_X86_QUIRK_MISC_ENABLE_NO_MWAIT is - disabled. - -KVM_X86_QUIRK_SLOT_ZAP_ALL By default, for KVM_X86_DEFAULT_VM VMs, KVM - invalidates all SPTEs in all memslots and - address spaces when a memslot is deleted or - moved. When this quirk is disabled (or the - VM type isn't KVM_X86_DEFAULT_VM), KVM only - ensures the backing memory of the deleted - or moved memslot isn't reachable, i.e KVM - _may_ invalidate only SPTEs related to the - memslot. - -KVM_X86_QUIRK_STUFF_FEATURE_MSRS By default, at vCPU creation, KVM sets the - vCPU's MSR_IA32_PERF_CAPABILITIES (0x345), - MSR_IA32_ARCH_CAPABILITIES (0x10a), - MSR_PLATFORM_INFO (0xce), and all VMX MSRs - (0x480..0x492) to the maximal capabilities - supported by KVM. KVM also sets - MSR_IA32_UCODE_REV (0x8b) to an arbitrary - value (which is different for Intel vs. - AMD). Lastly, when guest CPUID is set (by - userspace), KVM modifies select VMX MSR - fields to force consistency between guest - CPUID and L2's effective ISA. When this - quirk is disabled, KVM zeroes the vCPU's MSR - values (with two exceptions, see below), - i.e. treats the feature MSRs like CPUID - leaves and gives userspace full control of - the vCPU model definition. This quirk does - not affect VMX MSRs CR0/CR4_FIXED1 (0x487 - and 0x489), as KVM does now allow them to - be set by userspace (KVM sets them based on - guest CPUID, for safety purposes). - -KVM_X86_QUIRK_IGNORE_GUEST_PAT By default, on Intel platforms, KVM ignores - guest PAT and forces the effective memory - type to WB in EPT. The quirk is not available - on Intel platforms which are incapable of - safely honoring guest PAT (i.e., without CPU - self-snoop, KVM always ignores guest PAT and - forces effective memory type to WB). It is - also ignored on AMD platforms or, on Intel, - when a VM has non-coherent DMA devices - assigned; KVM always honors guest PAT in - such case. The quirk is needed to avoid - slowdowns on certain Intel Xeon platforms - (e.g. ICX, SPR) where self-snoop feature is - supported but UC is slow enough to cause - issues with some older guests that use - UC instead of WC to map the video RAM. - Userspace can disable the quirk to honor - guest PAT if it knows that there is no such - guest software, for example if it does not - expose a bochs graphics device (which is - known to have had a buggy driver). -=================================== ============================================ +======================================== ================================================ +KVM_X86_QUIRK_LINT0_REENABLED By default, the reset value for the LVT + LINT0 register is 0x700 (APIC_MODE_EXTINT). + When this quirk is disabled, the reset value + is 0x10000 (APIC_LVT_MASKED). + +KVM_X86_QUIRK_CD_NW_CLEARED By default, KVM clears CR0.CD and CR0.NW on + AMD CPUs to workaround buggy guest firmware + that runs in perpetuity with CR0.CD, i.e. + with caches in "no fill" mode. + + When this quirk is disabled, KVM does not + change the value of CR0.CD and CR0.NW. + +KVM_X86_QUIRK_LAPIC_MMIO_HOLE By default, the MMIO LAPIC interface is + available even when configured for x2APIC + mode. When this quirk is disabled, KVM + disables the MMIO LAPIC interface if the + LAPIC is in x2APIC mode. + +KVM_X86_QUIRK_OUT_7E_INC_RIP By default, KVM pre-increments %rip before + exiting to userspace for an OUT instruction + to port 0x7e. When this quirk is disabled, + KVM does not pre-increment %rip before + exiting to userspace. + +KVM_X86_QUIRK_MISC_ENABLE_NO_MWAIT When this quirk is disabled, KVM sets + CPUID.01H:ECX[bit 3] (MONITOR/MWAIT) if + IA32_MISC_ENABLE[bit 18] (MWAIT) is set. + Additionally, when this quirk is disabled, + KVM clears CPUID.01H:ECX[bit 3] if + IA32_MISC_ENABLE[bit 18] is cleared. + +KVM_X86_QUIRK_FIX_HYPERCALL_INSN By default, KVM rewrites guest + VMMCALL/VMCALL instructions to match the + vendor's hypercall instruction for the + system. When this quirk is disabled, KVM + will no longer rewrite invalid guest + hypercall instructions. Executing the + incorrect hypercall instruction will + generate a #UD within the guest. + +KVM_X86_QUIRK_MWAIT_NEVER_UD_FAULTS By default, KVM emulates MONITOR/MWAIT (if + they are intercepted) as NOPs regardless of + whether or not MONITOR/MWAIT are supported + according to guest CPUID. When this quirk + is disabled and KVM_X86_DISABLE_EXITS_MWAIT + is not set (MONITOR/MWAIT are intercepted), + KVM will inject a #UD on MONITOR/MWAIT if + they're unsupported per guest CPUID. Note, + KVM will modify MONITOR/MWAIT support in + guest CPUID on writes to MISC_ENABLE if + KVM_X86_QUIRK_MISC_ENABLE_NO_MWAIT is + disabled. + +KVM_X86_QUIRK_SLOT_ZAP_ALL By default, for KVM_X86_DEFAULT_VM VMs, KVM + invalidates all SPTEs in all memslots and + address spaces when a memslot is deleted or + moved. When this quirk is disabled (or the + VM type isn't KVM_X86_DEFAULT_VM), KVM only + ensures the backing memory of the deleted + or moved memslot isn't reachable, i.e KVM + _may_ invalidate only SPTEs related to the + memslot. + +KVM_X86_QUIRK_STUFF_FEATURE_MSRS By default, at vCPU creation, KVM sets the + vCPU's MSR_IA32_PERF_CAPABILITIES (0x345), + MSR_IA32_ARCH_CAPABILITIES (0x10a), + MSR_PLATFORM_INFO (0xce), and all VMX MSRs + (0x480..0x492) to the maximal capabilities + supported by KVM. KVM also sets + MSR_IA32_UCODE_REV (0x8b) to an arbitrary + value (which is different for Intel vs. + AMD). Lastly, when guest CPUID is set (by + userspace), KVM modifies select VMX MSR + fields to force consistency between guest + CPUID and L2's effective ISA. When this + quirk is disabled, KVM zeroes the vCPU's MSR + values (with two exceptions, see below), + i.e. treats the feature MSRs like CPUID + leaves and gives userspace full control of + the vCPU model definition. This quirk does + not affect VMX MSRs CR0/CR4_FIXED1 (0x487 + and 0x489), as KVM does now allow them to + be set by userspace (KVM sets them based on + guest CPUID, for safety purposes). + +KVM_X86_QUIRK_IGNORE_GUEST_PAT By default, on Intel platforms, KVM ignores + guest PAT and forces the effective memory + type to WB in EPT. The quirk is not available + on Intel platforms which are incapable of + safely honoring guest PAT (i.e., without CPU + self-snoop, KVM always ignores guest PAT and + forces effective memory type to WB). It is + also ignored on AMD platforms or, on Intel, + when a VM has non-coherent DMA devices + assigned; KVM always honors guest PAT in + such case. The quirk is needed to avoid + slowdowns on certain Intel Xeon platforms + (e.g. ICX, SPR) where self-snoop feature is + supported but UC is slow enough to cause + issues with some older guests that use + UC instead of WC to map the video RAM. + Userspace can disable the quirk to honor + guest PAT if it knows that there is no such + guest software, for example if it does not + expose a bochs graphics device (which is + known to have had a buggy driver). + +KVM_X86_QUIRK_VMCS12_ALLOW_FREEZE_IN_SMM By default, KVM relaxes the consistency + check for GUEST_IA32_DEBUGCTL in vmcs12 + to allow FREEZE_IN_SMM to be set. When + this quirk is disabled, KVM requires this + bit to be cleared. Note that the vmcs02 + bit is still completely controlled by the + host, regardless of the quirk setting. +======================================== ================================================ 7.32 KVM_CAP_MAX_VCPU_ID ------------------------ diff --git a/Documentation/virt/kvm/locking.rst b/Documentation/virt/kvm/locking.rst index ae8bce7fecbe..662231e958a0 100644 --- a/Documentation/virt/kvm/locking.rst +++ b/Documentation/virt/kvm/locking.rst @@ -17,6 +17,8 @@ The acquisition orders for mutexes are as follows: - kvm->lock is taken outside kvm->slots_lock and kvm->irq_lock +- vcpu->mutex is taken outside kvm->slots_lock and kvm->slots_arch_lock + - kvm->slots_lock is taken outside kvm->irq_lock, though acquiring them together is quite rare. |