diff options
Diffstat (limited to 'Documentation')
| -rw-r--r-- | Documentation/ABI/testing/sysfs-devices-system-cpu | 9 | ||||
| -rw-r--r-- | Documentation/admin-guide/kernel-parameters.txt | 11 | ||||
| -rw-r--r-- | Documentation/arm64/asymmetric-32bit.rst | 155 | ||||
| -rw-r--r-- | Documentation/arm64/index.rst | 1 | ||||
| -rw-r--r-- | Documentation/bpf/libbpf/libbpf_naming_convention.rst | 4 | ||||
| -rw-r--r-- | Documentation/devicetree/bindings/iio/st,st-sensors.yaml | 41 | ||||
| -rw-r--r-- | Documentation/gpu/rfc/i915_gem_lmem.rst | 109 | ||||
| -rw-r--r-- | Documentation/i2c/index.rst | 1 | ||||
| -rw-r--r-- | Documentation/networking/netdev-FAQ.rst | 17 | ||||
| -rw-r--r-- | Documentation/networking/nf_conntrack-sysctl.rst | 10 | ||||
| -rw-r--r-- | Documentation/networking/operstates.rst | 6 | ||||
| -rw-r--r-- | Documentation/userspace-api/seccomp_filter.rst | 2 | ||||
| -rw-r--r-- | Documentation/virt/kvm/api.rst | 30 | ||||
| -rw-r--r-- | Documentation/virt/kvm/locking.rst | 8 |
14 files changed, 220 insertions, 184 deletions
diff --git a/Documentation/ABI/testing/sysfs-devices-system-cpu b/Documentation/ABI/testing/sysfs-devices-system-cpu index edb19b31d710..b46ef147616a 100644 --- a/Documentation/ABI/testing/sysfs-devices-system-cpu +++ b/Documentation/ABI/testing/sysfs-devices-system-cpu @@ -494,6 +494,15 @@ Description: AArch64 CPU registers 'identification' directory exposes the CPU ID registers for identifying model and revision of the CPU. +What: /sys/devices/system/cpu/aarch32_el0 +Date: May 2021 +Contact: Linux ARM Kernel Mailing list <linux-arm-kernel@lists.infradead.org> +Description: Identifies the subset of CPUs in the system that can execute + AArch32 (32-bit ARM) applications. If present, the same format as + /sys/devices/system/cpu/{offline,online,possible,present} is used. + If absent, then all or none of the CPUs can execute AArch32 + applications and execve() will behave accordingly. + What: /sys/devices/system/cpu/cpu#/cpu_capacity Date: December 2016 Contact: Linux kernel mailing list <linux-kernel@vger.kernel.org> diff --git a/Documentation/admin-guide/kernel-parameters.txt b/Documentation/admin-guide/kernel-parameters.txt index 6f257e39d89e..309e68aaff7d 100644 --- a/Documentation/admin-guide/kernel-parameters.txt +++ b/Documentation/admin-guide/kernel-parameters.txt @@ -287,6 +287,17 @@ do not want to use tracing_snapshot_alloc() as it needs to be done where GFP_KERNEL allocations are allowed. + allow_mismatched_32bit_el0 [ARM64] + Allow execve() of 32-bit applications and setting of the + PER_LINUX32 personality on systems where only a strict + subset of the CPUs support 32-bit EL0. When this + parameter is present, the set of CPUs supporting 32-bit + EL0 is indicated by /sys/devices/system/cpu/aarch32_el0 + and hot-unplug operations may be restricted. + + See Documentation/arm64/asymmetric-32bit.rst for more + information. + amd_iommu= [HW,X86-64] Pass parameters to the AMD IOMMU driver in the system. Possible values are: diff --git a/Documentation/arm64/asymmetric-32bit.rst b/Documentation/arm64/asymmetric-32bit.rst new file mode 100644 index 000000000000..64a0b505da7d --- /dev/null +++ b/Documentation/arm64/asymmetric-32bit.rst @@ -0,0 +1,155 @@ +====================== +Asymmetric 32-bit SoCs +====================== + +Author: Will Deacon <will@kernel.org> + +This document describes the impact of asymmetric 32-bit SoCs on the +execution of 32-bit (``AArch32``) applications. + +Date: 2021-05-17 + +Introduction +============ + +Some Armv9 SoCs suffer from a big.LITTLE misfeature where only a subset +of the CPUs are capable of executing 32-bit user applications. On such +a system, Linux by default treats the asymmetry as a "mismatch" and +disables support for both the ``PER_LINUX32`` personality and +``execve(2)`` of 32-bit ELF binaries, with the latter returning +``-ENOEXEC``. If the mismatch is detected during late onlining of a +64-bit-only CPU, then the onlining operation fails and the new CPU is +unavailable for scheduling. + +Surprisingly, these SoCs have been produced with the intention of +running legacy 32-bit binaries. Unsurprisingly, that doesn't work very +well with the default behaviour of Linux. + +It seems inevitable that future SoCs will drop 32-bit support +altogether, so if you're stuck in the unenviable position of needing to +run 32-bit code on one of these transitionary platforms then you would +be wise to consider alternatives such as recompilation, emulation or +retirement. If neither of those options are practical, then read on. + +Enabling kernel support +======================= + +Since the kernel support is not completely transparent to userspace, +allowing 32-bit tasks to run on an asymmetric 32-bit system requires an +explicit "opt-in" and can be enabled by passing the +``allow_mismatched_32bit_el0`` parameter on the kernel command-line. + +For the remainder of this document we will refer to an *asymmetric +system* to mean an asymmetric 32-bit SoC running Linux with this kernel +command-line option enabled. + +Userspace impact +================ + +32-bit tasks running on an asymmetric system behave in mostly the same +way as on a homogeneous system, with a few key differences relating to +CPU affinity. + +sysfs +----- + +The subset of CPUs capable of running 32-bit tasks is described in +``/sys/devices/system/cpu/aarch32_el0`` and is documented further in +``Documentation/ABI/testing/sysfs-devices-system-cpu``. + +**Note:** CPUs are advertised by this file as they are detected and so +late-onlining of 32-bit-capable CPUs can result in the file contents +being modified by the kernel at runtime. Once advertised, CPUs are never +removed from the file. + +``execve(2)`` +------------- + +On a homogeneous system, the CPU affinity of a task is preserved across +``execve(2)``. This is not always possible on an asymmetric system, +specifically when the new program being executed is 32-bit yet the +affinity mask contains 64-bit-only CPUs. In this situation, the kernel +determines the new affinity mask as follows: + + 1. If the 32-bit-capable subset of the affinity mask is not empty, + then the affinity is restricted to that subset and the old affinity + mask is saved. This saved mask is inherited over ``fork(2)`` and + preserved across ``execve(2)`` of 32-bit programs. + + **Note:** This step does not apply to ``SCHED_DEADLINE`` tasks. + See `SCHED_DEADLINE`_. + + 2. Otherwise, the cpuset hierarchy of the task is walked until an + ancestor is found containing at least one 32-bit-capable CPU. The + affinity of the task is then changed to match the 32-bit-capable + subset of the cpuset determined by the walk. + + 3. On failure (i.e. out of memory), the affinity is changed to the set + of all 32-bit-capable CPUs of which the kernel is aware. + +A subsequent ``execve(2)`` of a 64-bit program by the 32-bit task will +invalidate the affinity mask saved in (1) and attempt to restore the CPU +affinity of the task using the saved mask if it was previously valid. +This restoration may fail due to intervening changes to the deadline +policy or cpuset hierarchy, in which case the ``execve(2)`` continues +with the affinity unchanged. + +Calls to ``sched_setaffinity(2)`` for a 32-bit task will consider only +the 32-bit-capable CPUs of the requested affinity mask. On success, the +affinity for the task is updated and any saved mask from a prior +``execve(2)`` is invalidated. + +``SCHED_DEADLINE`` +------------------ + +Explicit admission of a 32-bit deadline task to the default root domain +(e.g. by calling ``sched_setattr(2)``) is rejected on an asymmetric +32-bit system unless admission control is disabled by writing -1 to +``/proc/sys/kernel/sched_rt_runtime_us``. + +``execve(2)`` of a 32-bit program from a 64-bit deadline task will +return ``-ENOEXEC`` if the root domain for the task contains any +64-bit-only CPUs and admission control is enabled. Concurrent offlining +of 32-bit-capable CPUs may still necessitate the procedure described in +`execve(2)`_, in which case step (1) is skipped and a warning is +emitted on the console. + +**Note:** It is recommended that a set of 32-bit-capable CPUs are placed +into a separate root domain if ``SCHED_DEADLINE`` is to be used with +32-bit tasks on an asymmetric system. Failure to do so is likely to +result in missed deadlines. + +Cpusets +------- + +The affinity of a 32-bit task on an asymmetric system may include CPUs +that are not explicitly allowed by the cpuset to which it is attached. +This can occur as a result of the following two situations: + + - A 64-bit task attached to a cpuset which allows only 64-bit CPUs + executes a 32-bit program. + + - All of the 32-bit-capable CPUs allowed by a cpuset containing a + 32-bit task are offlined. + +In both of these cases, the new affinity is calculated according to step +(2) of the process described in `execve(2)`_ and the cpuset hierarchy is +unchanged irrespective of the cgroup version. + +CPU hotplug +----------- + +On an asymmetric system, the first detected 32-bit-capable CPU is +prevented from being offlined by userspace and any such attempt will +return ``-EPERM``. Note that suspend is still permitted even if the +primary CPU (i.e. CPU 0) is 64-bit-only. + +KVM +--- + +Although KVM will not advertise 32-bit EL0 support to any vCPUs on an +asymmetric system, a broken guest at EL1 could still attempt to execute +32-bit code at EL0. In this case, an exit from a vCPU thread in 32-bit +mode will return to host userspace with an ``exit_reason`` of +``KVM_EXIT_FAIL_ENTRY`` and will remain non-runnable until successfully +re-initialised by a subsequent ``KVM_ARM_VCPU_INIT`` operation. diff --git a/Documentation/arm64/index.rst b/Documentation/arm64/index.rst index 97d65ba12a35..4f840bac083e 100644 --- a/Documentation/arm64/index.rst +++ b/Documentation/arm64/index.rst @@ -10,6 +10,7 @@ ARM64 Architecture acpi_object_usage amu arm-acpi + asymmetric-32bit booting cpu-feature-registers elf_hwcaps diff --git a/Documentation/bpf/libbpf/libbpf_naming_convention.rst b/Documentation/bpf/libbpf/libbpf_naming_convention.rst index 3de1d51e41da..6bf9c5ac7576 100644 --- a/Documentation/bpf/libbpf/libbpf_naming_convention.rst +++ b/Documentation/bpf/libbpf/libbpf_naming_convention.rst @@ -108,7 +108,7 @@ This bump in ABI version is at most once per kernel development cycle. For example, if current state of ``libbpf.map`` is: -.. code-block:: c +.. code-block:: none LIBBPF_0.0.1 { global: @@ -121,7 +121,7 @@ For example, if current state of ``libbpf.map`` is: , and a new symbol ``bpf_func_c`` is being introduced, then ``libbpf.map`` should be changed like this: -.. code-block:: c +.. code-block:: none LIBBPF_0.0.1 { global: diff --git a/Documentation/devicetree/bindings/iio/st,st-sensors.yaml b/Documentation/devicetree/bindings/iio/st,st-sensors.yaml index b2a1e42c56fa..71de5631ebae 100644 --- a/Documentation/devicetree/bindings/iio/st,st-sensors.yaml +++ b/Documentation/devicetree/bindings/iio/st,st-sensors.yaml @@ -152,47 +152,6 @@ allOf: maxItems: 1 st,drdy-int-pin: false - - if: - properties: - compatible: - enum: - # Two intertial interrupts i.e. accelerometer/gyro interrupts - - st,h3lis331dl-accel - - st,l3g4200d-gyro - - st,l3g4is-gyro - - st,l3gd20-gyro - - st,l3gd20h-gyro - - st,lis2de12 - - st,lis2dw12 - - st,lis2hh12 - - st,lis2dh12-accel - - st,lis331dl-accel - - st,lis331dlh-accel - - st,lis3de - - st,lis3dh-accel - - st,lis3dhh - - st,lis3mdl-magn - - st,lng2dm-accel - - st,lps331ap-press - - st,lsm303agr-accel - - st,lsm303dlh-accel - - st,lsm303dlhc-accel - - st,lsm303dlm-accel - - st,lsm330-accel - - st,lsm330-gyro - - st,lsm330d-accel - - st,lsm330d-gyro - - st,lsm330dl-accel - - st,lsm330dl-gyro - - st,lsm330dlc-accel - - st,lsm330dlc-gyro - - st,lsm9ds0-gyro - - st,lsm9ds1-magn - then: - properties: - interrupts: - maxItems: 2 - required: - compatible - reg diff --git a/Documentation/gpu/rfc/i915_gem_lmem.rst b/Documentation/gpu/rfc/i915_gem_lmem.rst index 675ba8620d66..b421a3c1806e 100644 --- a/Documentation/gpu/rfc/i915_gem_lmem.rst +++ b/Documentation/gpu/rfc/i915_gem_lmem.rst @@ -18,114 +18,5 @@ real, with all the uAPI bits is: * Route shmem backend over to TTM SYSTEM for discrete * TTM purgeable object support * Move i915 buddy allocator over to TTM - * MMAP ioctl mode(see `I915 MMAP`_) - * SET/GET ioctl caching(see `I915 SET/GET CACHING`_) * Send RFC(with mesa-dev on cc) for final sign off on the uAPI * Add pciid for DG1 and turn on uAPI for real - -New object placement and region query uAPI -========================================== -Starting from DG1 we need to give userspace the ability to allocate buffers from -device local-memory. Currently the driver supports gem_create, which can place -buffers in system memory via shmem, and the usual assortment of other -interfaces, like dumb buffers and userptr. - -To support this new capability, while also providing a uAPI which will work -beyond just DG1, we propose to offer three new bits of uAPI: - -DRM_I915_QUERY_MEMORY_REGIONS ------------------------------ -New query ID which allows userspace to discover the list of supported memory -regions(like system-memory and local-memory) for a given device. We identify -each region with a class and instance pair, which should be unique. The class -here would be DEVICE or SYSTEM, and the instance would be zero, on platforms -like DG1. - -Side note: The class/instance design is borrowed from our existing engine uAPI, -where we describe every physical engine in terms of its class, and the -particular instance, since we can have more than one per class. - -In the future we also want to expose more information which can further -describe the capabilities of a region. - -.. kernel-doc:: include/uapi/drm/i915_drm.h - :functions: drm_i915_gem_memory_class drm_i915_gem_memory_class_instance drm_i915_memory_region_info drm_i915_query_memory_regions - -GEM_CREATE_EXT --------------- -New ioctl which is basically just gem_create but now allows userspace to provide -a chain of possible extensions. Note that if we don't provide any extensions and -set flags=0 then we get the exact same behaviour as gem_create. - -Side note: We also need to support PXP[1] in the near future, which is also -applicable to integrated platforms, and adds its own gem_create_ext extension, -which basically lets userspace mark a buffer as "protected". - -.. kernel-doc:: include/uapi/drm/i915_drm.h - :functions: drm_i915_gem_create_ext - -I915_GEM_CREATE_EXT_MEMORY_REGIONS ----------------------------------- -Implemented as an extension for gem_create_ext, we would now allow userspace to -optionally provide an immutable list of preferred placements at creation time, -in priority order, for a given buffer object. For the placements we expect -them each to use the class/instance encoding, as per the output of the regions -query. Having the list in priority order will be useful in the future when -placing an object, say during eviction. - -.. kernel-doc:: include/uapi/drm/i915_drm.h - :functions: drm_i915_gem_create_ext_memory_regions - -One fair criticism here is that this seems a little over-engineered[2]. If we -just consider DG1 then yes, a simple gem_create.flags or something is totally -all that's needed to tell the kernel to allocate the buffer in local-memory or -whatever. However looking to the future we need uAPI which can also support -upcoming Xe HP multi-tile architecture in a sane way, where there can be -multiple local-memory instances for a given device, and so using both class and -instance in our uAPI to describe regions is desirable, although specifically -for DG1 it's uninteresting, since we only have a single local-memory instance. - -Existing uAPI issues -==================== -Some potential issues we still need to resolve. - -I915 MMAP ---------- -In i915 there are multiple ways to MMAP GEM object, including mapping the same -object using different mapping types(WC vs WB), i.e multiple active mmaps per -object. TTM expects one MMAP at most for the lifetime of the object. If it -turns out that we have to backpedal here, there might be some potential -userspace fallout. - -I915 SET/GET CACHING --------------------- -In i915 we have set/get_caching ioctl. TTM doesn't let us to change this, but -DG1 doesn't support non-snooped pcie transactions, so we can just always -allocate as WB for smem-only buffers. If/when our hw gains support for -non-snooped pcie transactions then we must fix this mode at allocation time as -a new GEM extension. - -This is related to the mmap problem, because in general (meaning, when we're -not running on intel cpus) the cpu mmap must not, ever, be inconsistent with -allocation mode. - -Possible idea is to let the kernel picks the mmap mode for userspace from the -following table: - -smem-only: WB. Userspace does not need to call clflush. - -smem+lmem: We only ever allow a single mode, so simply allocate this as uncached -memory, and always give userspace a WC mapping. GPU still does snooped access -here(assuming we can't turn it off like on DG1), which is a bit inefficient. - -lmem only: always WC - -This means on discrete you only get a single mmap mode, all others must be -rejected. That's probably going to be a new default mode or something like -that. - -Links -===== -[1] https://patchwork.freedesktop.org/series/86798/ - -[2] https://gitlab.freedesktop.org/mesa/mesa/-/merge_requests/5599#note_553791 diff --git a/Documentation/i2c/index.rst b/Documentation/i2c/index.rst index 8b76217e370a..6270f1fd7d4e 100644 --- a/Documentation/i2c/index.rst +++ b/Documentation/i2c/index.rst @@ -17,6 +17,7 @@ Introduction busses/index i2c-topology muxes/i2c-mux-gpio + i2c-sysfs Writing device drivers ====================== diff --git a/Documentation/networking/netdev-FAQ.rst b/Documentation/networking/netdev-FAQ.rst index 91b2cf712801..e26532f49760 100644 --- a/Documentation/networking/netdev-FAQ.rst +++ b/Documentation/networking/netdev-FAQ.rst @@ -228,6 +228,23 @@ before posting to the mailing list. The patchwork build bot instance gets overloaded very easily and netdev@vger really doesn't need more traffic if we can help it. +netdevsim is great, can I extend it for my out-of-tree tests? +------------------------------------------------------------- + +No, `netdevsim` is a test vehicle solely for upstream tests. +(Please add your tests under tools/testing/selftests/.) + +We also give no guarantees that `netdevsim` won't change in the future +in a way which would break what would normally be considered uAPI. + +Is netdevsim considered a "user" of an API? +------------------------------------------- + +Linux kernel has a long standing rule that no API should be added unless +it has a real, in-tree user. Mock-ups and tests based on `netdevsim` are +strongly encouraged when adding new APIs, but `netdevsim` in itself +is **not** considered a use case/user. + Any other tips to help ensure my net/net-next patch gets OK'd? -------------------------------------------------------------- Attention to detail. Re-read your own work as if you were the diff --git a/Documentation/networking/nf_conntrack-sysctl.rst b/Documentation/networking/nf_conntrack-sysctl.rst index d31ed6c1cb0d..024d784157c8 100644 --- a/Documentation/networking/nf_conntrack-sysctl.rst +++ b/Documentation/networking/nf_conntrack-sysctl.rst @@ -191,19 +191,9 @@ nf_flowtable_tcp_timeout - INTEGER (seconds) TCP connections may be offloaded from nf conntrack to nf flow table. Once aged, the connection is returned to nf conntrack with tcp pickup timeout. -nf_flowtable_tcp_pickup - INTEGER (seconds) - default 120 - - TCP connection timeout after being aged from nf flow table offload. - nf_flowtable_udp_timeout - INTEGER (seconds) default 30 Control offload timeout for udp connections. UDP connections may be offloaded from nf conntrack to nf flow table. Once aged, the connection is returned to nf conntrack with udp pickup timeout. - -nf_flowtable_udp_pickup - INTEGER (seconds) - default 30 - - UDP connection timeout after being aged from nf flow table offload. diff --git a/Documentation/networking/operstates.rst b/Documentation/networking/operstates.rst index 9c918f7cb0e8..1ee2141e8ef1 100644 --- a/Documentation/networking/operstates.rst +++ b/Documentation/networking/operstates.rst @@ -73,7 +73,9 @@ IF_OPER_LOWERLAYERDOWN (3): state (f.e. VLAN). IF_OPER_TESTING (4): - Unused in current kernel. + Interface is in testing mode, for example executing driver self-tests + or media (cable) test. It can't be used for normal traffic until tests + complete. IF_OPER_DORMANT (5): Interface is L1 up, but waiting for an external event, f.e. for a @@ -111,7 +113,7 @@ it as lower layer. Note that for certain kind of soft-devices, which are not managing any real hardware, it is possible to set this bit from userspace. One -should use TVL IFLA_CARRIER to do so. +should use TLV IFLA_CARRIER to do so. netif_carrier_ok() can be used to query that bit. diff --git a/Documentation/userspace-api/seccomp_filter.rst b/Documentation/userspace-api/seccomp_filter.rst index d61219889e49..539e9d4a4860 100644 --- a/Documentation/userspace-api/seccomp_filter.rst +++ b/Documentation/userspace-api/seccomp_filter.rst @@ -263,7 +263,7 @@ Userspace can also add file descriptors to the notifying process via ``ioctl(SECCOMP_IOCTL_NOTIF_ADDFD)``. The ``id`` member of ``struct seccomp_notif_addfd`` should be the same ``id`` as in ``struct seccomp_notif``. The ``newfd_flags`` flag may be used to set flags -like O_EXEC on the file descriptor in the notifying process. If the supervisor +like O_CLOEXEC on the file descriptor in the notifying process. If the supervisor wants to inject the file descriptor with a specific number, the ``SECCOMP_ADDFD_FLAG_SETFD`` flag can be used, and set the ``newfd`` member to the specific number to use. If that file descriptor is already open in the diff --git a/Documentation/virt/kvm/api.rst b/Documentation/virt/kvm/api.rst index c7b165ca70b6..dae68e68ca23 100644 --- a/Documentation/virt/kvm/api.rst +++ b/Documentation/virt/kvm/api.rst @@ -855,7 +855,7 @@ in-kernel irqchip (GIC), and for in-kernel irqchip can tell the GIC to use PPIs designated for specific cpus. The irq field is interpreted like this:: - bits: | 31 ... 28 | 27 ... 24 | 23 ... 16 | 15 ... 0 | + bits: | 31 ... 28 | 27 ... 24 | 23 ... 16 | 15 ... 0 | field: | vcpu2_index | irq_type | vcpu_index | irq_id | The irq_type field has the following values: @@ -2149,10 +2149,10 @@ prior to calling the KVM_RUN ioctl. Errors: ====== ============================================================ - ENOENT no such register - EINVAL invalid register ID, or no such register or used with VMs in + ENOENT no such register + EINVAL invalid register ID, or no such register or used with VMs in protected virtualization mode on s390 - EPERM (arm64) register access not allowed before vcpu finalization + EPERM (arm64) register access not allowed before vcpu finalization ====== ============================================================ (These error codes are indicative only: do not rely on a specific error @@ -2590,10 +2590,10 @@ following id bit patterns:: Errors include: ======== ============================================================ - ENOENT no such register - EINVAL invalid register ID, or no such register or used with VMs in + ENOENT no such register + EINVAL invalid register ID, or no such register or used with VMs in protected virtualization mode on s390 - EPERM (arm64) register access not allowed before vcpu finalization + EPERM (arm64) register access not allowed before vcpu finalization ======== ============================================================ (These error codes are indicative only: do not rely on a specific error @@ -3112,13 +3112,13 @@ current state. "addr" is ignored. Errors: ====== ================================================================= - EINVAL the target is unknown, or the combination of features is invalid. - ENOENT a features bit specified is unknown. + EINVAL the target is unknown, or the combination of features is invalid. + ENOENT a features bit specified is unknown. ====== ================================================================= This tells KVM what type of CPU to present to the guest, and what -optional features it should have. This will cause a reset of the cpu -registers to their initial values. If this is not called, KVM_RUN will +optional features it should have. This will cause a reset of the cpu +registers to their initial values. If this is not called, KVM_RUN will return ENOEXEC for that vcpu. The initial values are defined as: @@ -3239,8 +3239,8 @@ VCPU matching underlying host. Errors: ===== ============================================================== - E2BIG the reg index list is too big to fit in the array specified by - the user (the number required will be written into n). + E2BIG the reg index list is too big to fit in the array specified by + the user (the number required will be written into n). ===== ============================================================== :: @@ -3288,7 +3288,7 @@ specific device. ARM/arm64 divides the id field into two parts, a device id and an address type id specific to the individual device:: - bits: | 63 ... 32 | 31 ... 16 | 15 ... 0 | + bits: | 63 ... 32 | 31 ... 16 | 15 ... 0 | field: | 0x00000000 | device id | addr type id | ARM/arm64 currently only require this when using the in-kernel GIC @@ -7049,7 +7049,7 @@ In combination with KVM_CAP_X86_USER_SPACE_MSR, this allows user space to trap and emulate MSRs that are outside of the scope of KVM as well as limit the attack surface on KVM's MSR emulation code. -8.28 KVM_CAP_ENFORCE_PV_CPUID +8.28 KVM_CAP_ENFORCE_PV_FEATURE_CPUID ----------------------------- Architectures: x86 diff --git a/Documentation/virt/kvm/locking.rst b/Documentation/virt/kvm/locking.rst index 35eca377543d..88fa495abbac 100644 --- a/Documentation/virt/kvm/locking.rst +++ b/Documentation/virt/kvm/locking.rst @@ -25,10 +25,10 @@ On x86: - vcpu->mutex is taken outside kvm->arch.hyperv.hv_lock -- kvm->arch.mmu_lock is an rwlock. kvm->arch.tdp_mmu_pages_lock is - taken inside kvm->arch.mmu_lock, and cannot be taken without already - holding kvm->arch.mmu_lock (typically with ``read_lock``, otherwise - there's no need to take kvm->arch.tdp_mmu_pages_lock at all). +- kvm->arch.mmu_lock is an rwlock. kvm->arch.tdp_mmu_pages_lock and + kvm->arch.mmu_unsync_pages_lock are taken inside kvm->arch.mmu_lock, and + cannot be taken without already holding kvm->arch.mmu_lock (typically with + ``read_lock`` for the TDP MMU, thus the need for additional spinlocks). Everything else is a leaf: no other lock is taken inside the critical sections. |