Commit Graph
16 Commits
Author SHA1 Message Date
Bibo Mao c43dce6f13 LoongArch: KVM: Make vcpu_is_preempted() as a macro rather than function
vcpu_is_preempted() is performance sensitive that called in function
osq_lock(), here make it as a macro. So that parameter is not parsed
at most time, it can avoid cache line thrashing across numa nodes.

Here is part of UnixBench result on Loongson-3C5000 DualWay machine with
32 cores and 2 numa nodes.

          original    inline   macro
execl     7025.7      6991.2   7242.3
fstime    474.6       703.1    1071

From the test result, making vcpu_is_preempted() as a macro is the best,
and there is some improvment compared with the original function method.

Signed-off-by: Bibo Mao <maobibo@loongson.cn>
Signed-off-by: Huacai Chen <chenhuacai@loongson.cn>
2026-04-09 18:56:36 +08:00
Linus Torvalds cb5573868e Merge tag 'for-linus' of git://git.kernel.org/pub/scm/virt/kvm/kvm
Pull KVM updates from Paolo Bonzini:
 "Loongarch:

   - Add more CPUCFG mask bits

   - Improve feature detection

   - Add lazy load support for FPU and binary translation (LBT) register
     state

   - Fix return value for memory reads from and writes to in-kernel
     devices

   - Add support for detecting preemption from within a guest

   - Add KVM steal time test case to tools/selftests

  ARM:

   - Add support for FEAT_IDST, allowing ID registers that are not
     implemented to be reported as a normal trap rather than as an UNDEF
     exception

   - Add sanitisation of the VTCR_EL2 register, fixing a number of
     UXN/PXN/XN bugs in the process

   - Full handling of RESx bits, instead of only RES0, and resulting in
     SCTLR_EL2 being added to the list of sanitised registers

   - More pKVM fixes for features that are not supposed to be exposed to
     guests

   - Make sure that MTE being disabled on the pKVM host doesn't give it
     the ability to attack the hypervisor

   - Allow pKVM's host stage-2 mappings to use the Force Write Back
     version of the memory attributes by using the "pass-through'
     encoding

   - Fix trapping of ICC_DIR_EL1 on GICv5 hosts emulating GICv3 for the
     guest

   - Preliminary work for guest GICv5 support

   - A bunch of debugfs fixes, removing pointless custom iterators
     stored in guest data structures

   - A small set of FPSIMD cleanups

   - Selftest fixes addressing the incorrect alignment of page
     allocation

   - Other assorted low-impact fixes and spelling fixes

  RISC-V:

   - Fixes for issues discoverd by KVM API fuzzing in
     kvm_riscv_aia_imsic_has_attr(), kvm_riscv_aia_imsic_rw_attr(), and
     kvm_riscv_vcpu_aia_imsic_update()

   - Allow Zalasr, Zilsd and Zclsd extensions for Guest/VM

   - Transparent huge page support for hypervisor page tables

   - Adjust the number of available guest irq files based on MMIO
     register sizes found in the device tree or the ACPI tables

   - Add RISC-V specific paging modes to KVM selftests

   - Detect paging mode at runtime for selftests

  s390:

   - Performance improvement for vSIE (aka nested virtualization)

   - Completely new memory management. s390 was a special snowflake that
     enlisted help from the architecture's page table management to
     build hypervisor page tables, in particular enabling sharing the
     last level of page tables. This however was a lot of code (~3K
     lines) in order to support KVM, and also blocked several features.
     The biggest advantages is that the page size of userspace is
     completely independent of the page size used by the guest:
     userspace can mix normal pages, THPs and hugetlbfs as it sees fit,
     and in fact transparent hugepages were not possible before. It's
     also now possible to have nested guests and guests with huge pages
     running on the same host

   - Maintainership change for s390 vfio-pci

   - Small quality of life improvement for protected guests

  x86:

   - Add support for giving the guest full ownership of PMU hardware
     (contexted switched around the fastpath run loop) and allowing
     direct access to data MSRs and PMCs (restricted by the vPMU model).

     KVM still intercepts access to control registers, e.g. to enforce
     event filtering and to prevent the guest from profiling sensitive
     host state. This is more accurate, since it has no risk of
     contention and thus dropped events, and also has significantly less
     overhead.

     For more information, see the commit message for merge commit
     bf2c3138ae ("Merge tag 'kvm-x86-pmu-6.20' ...")

   - Disallow changing the virtual CPU model if L2 is active, for all
     the same reasons KVM disallows change the model after the first
     KVM_RUN

   - Fix a bug where KVM would incorrectly reject host accesses to PV
     MSRs when running with KVM_CAP_ENFORCE_PV_FEATURE_CPUID enabled,
     even if those were advertised as supported to userspace,

   - Fix a bug with protected guest state (SEV-ES/SNP and TDX) VMs,
     where KVM would attempt to read CR3 configuring an async #PF entry

   - Fail the build if EXPORT_SYMBOL_GPL or EXPORT_SYMBOL is used in KVM
     (for x86 only) to enforce usage of EXPORT_SYMBOL_FOR_KVM_INTERNAL.
     Only a few exports that are intended for external usage, and those
     are allowed explicitly

   - When checking nested events after a vCPU is unblocked, ignore
     -EBUSY instead of WARNing. Userspace can sometimes put the vCPU
     into what should be an impossible state, and spurious exit to
     userspace on -EBUSY does not really do anything to solve the issue

   - Also throw in the towel and drop the WARN on INIT/SIPI being
     blocked when vCPU is in Wait-For-SIPI, which also resulted in
     playing whack-a-mole with syzkaller stuffing architecturally
     impossible states into KVM

   - Add support for new Intel instructions that don't require anything
     beyond enumerating feature flags to userspace

   - Grab SRCU when reading PDPTRs in KVM_GET_SREGS2

   - Add WARNs to guard against modifying KVM's CPU caps outside of the
     intended setup flow, as nested VMX in particular is sensitive to
     unexpected changes in KVM's golden configuration

   - Add a quirk to allow userspace to opt-in to actually suppress EOI
     broadcasts when the suppression feature is enabled by the guest
     (currently limited to split IRQCHIP, i.e. userspace I/O APIC).
     Sadly, simply fixing KVM to honor Suppress EOI Broadcasts isn't an
     option as some userspaces have come to rely on KVM's buggy behavior
     (KVM advertises Supress EOI Broadcast irrespective of whether or
     not userspace I/O APIC supports Directed EOIs)

   - Clean up KVM's handling of marking mapped vCPU pages dirty

   - Drop a pile of *ancient* sanity checks hidden behind in KVM's
     unused ASSERT() macro, most of which could be trivially triggered
     by the guest and/or user, and all of which were useless

   - Fold "struct dest_map" into its sole user, "struct rtc_status", to
     make it more obvious what the weird parameter is used for, and to
     allow fropping these RTC shenanigans if CONFIG_KVM_IOAPIC=n

   - Bury all of ioapic.h, i8254.h and related ioctls (including
     KVM_CREATE_IRQCHIP) behind CONFIG_KVM_IOAPIC=y

   - Add a regression test for recent APICv update fixes

   - Handle "hardware APIC ISR", a.k.a. SVI, updates in
     kvm_apic_update_apicv() to consolidate the updates, and to
     co-locate SVI updates with the updates for KVM's own cache of ISR
     information

   - Drop a dead function declaration

   - Minor cleanups

  x86 (Intel):

   - Rework KVM's handling of VMCS updates while L2 is active to
     temporarily switch to vmcs01 instead of deferring the update until
     the next nested VM-Exit.

     The deferred updates approach directly contributed to several bugs,
     was proving to be a maintenance burden due to the difficulty in
     auditing the correctness of deferred updates, and was polluting
     "struct nested_vmx" with a growing pile of booleans

   - Fix an SGX bug where KVM would incorrectly try to handle EPCM page
     faults, and instead always reflect them into the guest. Since KVM
     doesn't shadow EPCM entries, EPCM violations cannot be due to KVM
     interference and can't be resolved by KVM

   - Fix a bug where KVM would register its posted interrupt wakeup
     handler even if loading kvm-intel.ko ultimately failed

   - Disallow access to vmcb12 fields that aren't fully supported,
     mostly to avoid weirdness and complexity for FRED and other
     features, where KVM wants enable VMCS shadowing for fields that
     conditionally exist

   - Print out the "bad" offsets and values if kvm-intel.ko refuses to
     load (or refuses to online a CPU) due to a VMCS config mismatch

  x86 (AMD):

   - Drop a user-triggerable WARN on nested_svm_load_cr3() failure

   - Add support for virtualizing ERAPS. Note, correct virtualization of
     ERAPS relies on an upcoming, publicly announced change in the APM
     to reduce the set of conditions where hardware (i.e. KVM) *must*
     flush the RAP

   - Ignore nSVM intercepts for instructions that are not supported
     according to L1's virtual CPU model

   - Add support for expedited writes to the fast MMIO bus, a la VMX's
     fastpath for EPT Misconfig

   - Don't set GIF when clearing EFER.SVME, as GIF exists independently
     of SVM, and allow userspace to restore nested state with GIF=0

   - Treat exit_code as an unsigned 64-bit value through all of KVM

   - Add support for fetching SNP certificates from userspace

   - Fix a bug where KVM would use vmcb02 instead of vmcb01 when
     emulating VMLOAD or VMSAVE on behalf of L2

   - Misc fixes and cleanups

  x86 selftests:

   - Add a regression test for TPR<=>CR8 synchronization and IRQ masking

   - Overhaul selftest's MMU infrastructure to genericize stage-2 MMU
     support, and extend x86's infrastructure to support EPT and NPT
     (for L2 guests)

   - Extend several nested VMX tests to also cover nested SVM

   - Add a selftest for nested VMLOAD/VMSAVE

   - Rework the nested dirty log test, originally added as a regression
     test for PML where KVM logged L2 GPAs instead of L1 GPAs, to
     improve test coverage and to hopefully make the test easier to
     understand and maintain

  guest_memfd:

   - Remove kvm_gmem_populate()'s preparation tracking and half-baked
     hugepage handling. SEV/SNP was the only user of the tracking and it
     can do it via the RMP

   - Retroactively document and enforce (for SNP) that
     KVM_SEV_SNP_LAUNCH_UPDATE and KVM_TDX_INIT_MEM_REGION require the
     source page to be 4KiB aligned, to avoid non-trivial complexity for
     something that no known VMM seems to be doing and to avoid an API
     special case for in-place conversion, which simply can't support
     unaligned sources

   - When populating guest_memfd memory, GUP the source page in common
     code and pass the refcounted page to the vendor callback, instead
     of letting vendor code do the heavy lifting. Doing so avoids a
     looming deadlock bug with in-place due an AB-BA conflict betwee
     mmap_lock and guest_memfd's filemap invalidate lock

  Generic:

   - Fix a bug where KVM would ignore the vCPU's selected address space
     when creating a vCPU-specific mapping of guest memory. Actually
     this bug could not be hit even on x86, the only architecture with
     multiple address spaces, but it's a bug nevertheless"

* tag 'for-linus' of git://git.kernel.org/pub/scm/virt/kvm/kvm: (267 commits)
  KVM: s390: Increase permitted SE header size to 1 MiB
  MAINTAINERS: Replace backup for s390 vfio-pci
  KVM: s390: vsie: Fix race in acquire_gmap_shadow()
  KVM: s390: vsie: Fix race in walk_guest_tables()
  KVM: s390: Use guest address to mark guest page dirty
  irqchip/riscv-imsic: Adjust the number of available guest irq files
  RISC-V: KVM: Transparent huge page support
  RISC-V: KVM: selftests: Add Zalasr extensions to get-reg-list test
  RISC-V: KVM: Allow Zalasr extensions for Guest/VM
  KVM: riscv: selftests: Add riscv vm satp modes
  KVM: riscv: selftests: add Zilsd and Zclsd extension to get-reg-list test
  riscv: KVM: allow Zilsd and Zclsd extensions for Guest/VM
  RISC-V: KVM: Skip IMSIC update if vCPU IMSIC state is not initialized
  RISC-V: KVM: Fix null pointer dereference in kvm_riscv_aia_imsic_rw_attr()
  RISC-V: KVM: Fix null pointer dereference in kvm_riscv_aia_imsic_has_attr()
  RISC-V: KVM: Remove unnecessary 'ret' assignment
  KVM: s390: Add explicit padding to struct kvm_s390_keyop
  KVM: LoongArch: selftests: Add steal time test case
  LoongArch: KVM: Add paravirt vcpu_is_preempted() support in guest side
  LoongArch: KVM: Add paravirt preempt feature in hypervisor side
  ...
2026-02-13 11:31:15 -08:00
Bibo Mao 872d277a1e LoongArch: KVM: Add paravirt vcpu_is_preempted() support in guest side
Function vcpu_is_preempted() is used to check whether vCPU is preempted
or not. Here add the implementation with vcpu_is_preempted() when option
CONFIG_PARAVIRT is enabled.

Acked-by: Juergen Gross <jgross@suse.com>
Signed-off-by: Bibo Mao <maobibo@loongson.cn>
Signed-off-by: Huacai Chen <chenhuacai@loongson.cn>
2026-02-06 09:28:01 +08:00
Juergen Gross b8431b901e loongarch/paravirt: Use common code for paravirt_steal_clock()
Remove the arch specific variant of paravirt_steal_clock() and use
the common one instead.

Signed-off-by: Juergen Gross <jgross@suse.com>
Signed-off-by: Borislav Petkov (AMD) <bp@alien8.de>
Reviewed-by: Bibo Mao <maobibo@loongson.cn>
Acked-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Link: https://patch.msgid.link/20260105110520.21356-10-jgross@suse.com
2026-01-12 16:47:20 +01:00
Juergen Gross e6b2aa6d40 sched: Move clock related paravirt code to kernel/sched
Paravirt clock related functions are available in multiple archs.

In order to share the common parts, move the common static keys
to kernel/sched/ and remove them from the arch specific files.

Make a common paravirt_steal_clock() implementation available in
kernel/sched/cputime.c, guarding it with a new config option
CONFIG_HAVE_PV_STEAL_CLOCK_GEN, which can be selected by an arch
in case it wants to use that common variant.

Signed-off-by: Juergen Gross <jgross@suse.com>
Signed-off-by: Borislav Petkov (AMD) <bp@alien8.de>
Acked-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Link: https://patch.msgid.link/20260105110520.21356-7-jgross@suse.com
2026-01-12 15:39:14 +01:00
Huacai Chen 7d69294b8a LoongArch: Fix build warnings about export.h
After commit a934a57a42 ("scripts/misc-check: check missing #include
<linux/export.h> when W=1") and 7d95680d64 ("scripts/misc-check:
check unnecessary #include <linux/export.h> when W=1"), we get some build
warnings with W=1:

arch/loongarch/kernel/acpi.c: warning: EXPORT_SYMBOL() is used, but #include <linux/export.h> is missing
arch/loongarch/kernel/alternative.c: warning: EXPORT_SYMBOL() is used, but #include <linux/export.h> is missing
arch/loongarch/kernel/kfpu.c: warning: EXPORT_SYMBOL() is used, but #include <linux/export.h> is missing
arch/loongarch/kernel/traps.c: warning: EXPORT_SYMBOL() is used, but #include <linux/export.h> is missing
arch/loongarch/kernel/unwind_guess.c: warning: EXPORT_SYMBOL() is used, but #include <linux/export.h> is missing
arch/loongarch/kernel/unwind_orc.c: warning: EXPORT_SYMBOL() is used, but #include <linux/export.h> is missing
arch/loongarch/kernel/unwind_prologue.c: warning: EXPORT_SYMBOL() is used, but #include <linux/export.h> is missing
arch/loongarch/lib/crc32-loongarch.c: warning: EXPORT_SYMBOL() is used, but #include <linux/export.h> is missing
arch/loongarch/lib/csum.c: warning: EXPORT_SYMBOL() is used, but #include <linux/export.h> is missing
arch/loongarch/kernel/elf.c: warning: EXPORT_SYMBOL() is not used, but #include <linux/export.h> is present
arch/loongarch/kernel/paravirt.c: warning: EXPORT_SYMBOL() is not used, but #include <linux/export.h> is present
arch/loongarch/pci/pci.c: warning: EXPORT_SYMBOL() is not used, but #include <linux/export.h> is present

So fix these build warnings for LoongArch.

Reviewed-by: Masahiro Yamada <masahiroy@kernel.org>
Signed-off-by: Huacai Chen <chenhuacai@loongson.cn>
2025-06-26 20:07:18 +08:00
Bibo Mao 6ce031e5d6 LoongArch: Fix AP booting issue in VM mode
Native IPI is used for AP booting, because it is the booting interface
between OS and BIOS firmware. The paravirt IPI is only used inside OS,
and native IPI is necessary to boot AP.

When booting AP, we write the kernel entry address in the HW mailbox of
AP and send IPI interrupt to it. AP executes idle instruction and waits
for interrupts or SW events, then clears IPI interrupt and jumps to the
kernel entry from HW mailbox.

Between writing HW mailbox and sending IPI, AP can be woken up by SW
events and jumps to the kernel entry, so ACTION_BOOT_CPU IPI interrupt
will keep pending during AP booting. And native IPI interrupt handler
needs be registered so that it can clear pending native IPI, else there
will be endless interrupts during AP booting stage.

Here native IPI interrupt is initialized even if paravirt IPI is used.

Cc: stable@vger.kernel.org
Fixes: 74c16b2e2b ("LoongArch: KVM: Add PV IPI support on guest side")
Signed-off-by: Bibo Mao <maobibo@loongson.cn>
Signed-off-by: Huacai Chen <chenhuacai@loongson.cn>
2024-11-12 16:35:39 +08:00
Linus Torvalds cb69d86550 Merge tag 'irq-core-2024-09-16' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip
Pull irq updates from Thomas Gleixner:
 "Core:

   - Remove a global lock in the affinity setting code

     The lock protects a cpumask for intermediate results and the lock
     causes a bottleneck on simultaneous start of multiple virtual
     machines. Replace the lock and the static cpumask with a per CPU
     cpumask which is nicely serialized by raw spinlock held when
     executing this code.

   - Provide support for giving a suffix to interrupt domain names.

     That's required to support devices with subfunctions so that the
     domain names are distinct even if they originate from the same
     device node.

   - The usual set of cleanups and enhancements all over the place

  Drivers:

   - Support for longarch AVEC interrupt chip

   - Refurbishment of the Armada driver so it can be extended for new
     variants.

   - The usual set of cleanups and enhancements all over the place"

* tag 'irq-core-2024-09-16' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip: (73 commits)
  genirq: Use cpumask_intersects()
  genirq/cpuhotplug: Use cpumask_intersects()
  irqchip/apple-aic: Only access system registers on SoCs which provide them
  irqchip/apple-aic: Add a new "Global fast IPIs only" feature level
  irqchip/apple-aic: Skip unnecessary enabling of use_fast_ipi
  dt-bindings: apple,aic: Document A7-A11 compatibles
  irqdomain: Use IS_ERR_OR_NULL() in irq_domain_trim_hierarchy()
  genirq/msi: Use kmemdup_array() instead of kmemdup()
  genirq/proc: Change the return value for set affinity permission error
  genirq/proc: Use irq_move_pending() in show_irq_affinity()
  genirq/proc: Correctly set file permissions for affinity control files
  genirq: Get rid of global lock in irq_do_set_affinity()
  genirq: Fix typo in struct comment
  irqchip/loongarch-avec: Add AVEC irqchip support
  irqchip/loongson-pch-msi: Prepare get_pch_msi_handle() for AVECINTC
  irqchip/loongson-eiointc: Rename CPUHP_AP_IRQ_LOONGARCH_STARTING
  LoongArch: Architectural preparation for AVEC irqchip
  LoongArch: Move irqchip function prototypes to irq-loongson.h
  irqchip/loongson-pch-msi: Switch to MSI parent domains
  softirq: Remove unused 'action' parameter from action callback
  ...
2024-09-17 07:09:17 +02:00
Bibo Mao 3abb708ec0 LoongArch: KVM: Implement function kvm_para_has_feature()
Implement function kvm_para_has_feature() to detect supported paravirt
features. It can be used by device driver to detect and enable paravirt
features, such as the EIOINTC irqchip driver is able to detect feature
KVM_FEATURE_VIRT_EXTIOI and do some optimization.

Signed-off-by: Bibo Mao <maobibo@loongson.cn>
Signed-off-by: Huacai Chen <chenhuacai@loongson.cn>
2024-09-12 22:56:14 +08:00
Bibo Mao cdc118f802 LoongArch: KVM: Enable paravirt feature control from VMM
Export kernel paravirt features to user space, so that VMM can control
each single paravirt feature. By default paravirt features will be the
same with kvm supported features if VMM does not set it.

Also a new feature KVM_FEATURE_VIRT_EXTIOI is added which can be set
from user space. This feature indicates that the virt EIOINTC can route
interrupts to 256 vCPUs, rather than 4 vCPUs like with real HW.

Signed-off-by: Bibo Mao <maobibo@loongson.cn>
Signed-off-by: Huacai Chen <chenhuacai@loongson.cn>
2024-09-12 20:53:40 +08:00
Bibo Mao e5ba90abb2 LoongArch: Revert qspinlock to test-and-set simple lock on VM
Similar with x86, when VM is detected, revert to a simple test-and-set
lock to avoid the horrors of queue preemption.

Tested on 3C5000 Dual-way machine with 32 cores and 2 numa nodes,
test case is kcbench on kernel mainline 6.10, the detailed command is
"kcbench --src /root/src/linux"

Performance on host machine
                      kernel compile time       performance impact
   Original           150.29 seconds
   With patch         150.19 seconds            almost no impact

Performance on virtual machine:
1. 1 VM with 32 vCPUs and 2 numa node, numa node pinned
                      kernel compile time       performance impact
   Original           170.87 seconds
   With patch         171.73 seconds            almost no impact

2. 2 VMs, each VM with 32 vCPUs and 2 numa node, numa node pinned
                      kernel compile time       performance impact
   Original           2362.04 seconds
   With patch         354.73  seconds            +565%

Signed-off-by: Bibo Mao <maobibo@loongson.cn>
Signed-off-by: Huacai Chen <chenhuacai@loongson.cn>
2024-09-11 23:26:32 +08:00
Tianyang Zhang ae16f05c92 irqchip/loongarch-avec: Add AVEC irqchip support
Introduce the advanced extended interrupt controllers (AVECINTC). This
feature will allow each core to have 256 independent interrupt vectors
and MSI interrupts can be independently routed to any vector on any CPU.

The whole topology of irqchips in LoongArch machines looks like this if
AVECINTC is supported:

  +-----+     +-----------------------+     +-------+
  | IPI | --> |        CPUINTC        | <-- | Timer |
  +-----+     +-----------------------+     +-------+
               ^          ^          ^
               |          |          |
        +---------+ +----------+ +---------+     +-------+
        | EIOINTC | | AVECINTC | | LIOINTC | <-- | UARTs |
        +---------+ +----------+ +---------+     +-------+
             ^            ^
             |            |
        +---------+  +---------+
        | PCH-PIC |  | PCH-MSI |
        +---------+  +---------+
          ^     ^           ^
          |     |           |
  +---------+ +---------+ +---------+
  | Devices | | PCH-LPC | | Devices |
  +---------+ +---------+ +---------+
                   ^
                   |
              +---------+
              | Devices |
              +---------+

Co-developed-by: Jianmin Lv <lvjianmin@loongson.cn>
Signed-off-by: Jianmin Lv <lvjianmin@loongson.cn>
Co-developed-by: Liupu Wang <wangliupu@loongson.cn>
Signed-off-by: Liupu Wang <wangliupu@loongson.cn>
Co-developed-by: Huacai Chen <chenhuacai@loongson.cn>
Signed-off-by: Huacai Chen <chenhuacai@loongson.cn>
Signed-off-by: Tianyang Zhang <zhangtianyang@loongson.cn>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Link: https://lore.kernel.org/all/20240823104337.25577-2-zhangtianyang@loongson.cn
2024-08-23 20:40:27 +02:00
Linus Torvalds a362ade892 Merge tag 'loongarch-6.11' of git://git.kernel.org/pub/scm/linux/kernel/git/chenhuacai/linux-loongson
Pull LoongArch updates from Huacai Chen:

 - Define __ARCH_WANT_NEW_STAT in unistd.h

 - Always enumerate MADT and setup logical-physical CPU mapping

 - Add irq_work support via self IPIs

 - Add RANDOMIZE_KSTACK_OFFSET support

 - Add ARCH_HAS_PTE_DEVMAP support

 - Add ARCH_HAS_DEBUG_VM_PGTABLE support

 - Add writecombine support for DMW-based ioremap()

 - Add architectural preparation for CPUFreq

 - Add ACPI standard hardware register based S3 support

 - Add support for relocating the kernel with RELR relocation

 - Some bug fixes and other small changes

* tag 'loongarch-6.11' of git://git.kernel.org/pub/scm/linux/kernel/git/chenhuacai/linux-loongson:
  LoongArch: Make the users of larch_insn_gen_break() constant
  LoongArch: Check TIF_LOAD_WATCH to enable user space watchpoint
  LoongArch: Use rustc option -Zdirect-access-external-data
  LoongArch: Add support for relocating the kernel with RELR relocation
  LoongArch: Remove a redundant checking in relocator
  LoongArch: Use correct API to map cmdline in relocate_kernel()
  LoongArch: Automatically disable KASLR for hibernation
  LoongArch: Add ACPI standard hardware register based S3 support
  LoongArch: Add architectural preparation for CPUFreq
  LoongArch: Add writecombine support for DMW-based ioremap()
  LoongArch: Add ARCH_HAS_DEBUG_VM_PGTABLE support
  LoongArch: Add ARCH_HAS_PTE_DEVMAP support
  LoongArch: Add RANDOMIZE_KSTACK_OFFSET support
  LoongArch: Add irq_work support via self IPIs
  LoongArch: Always enumerate MADT and setup logical-physical CPU mapping
  LoongArch: Define __ARCH_WANT_NEW_STAT in unistd.h
2024-07-22 13:44:22 -07:00
Huacai Chen 08f417db70 LoongArch: Add irq_work support via self IPIs
Add irq_work support for LoongArch via self IPIs. This make it possible
to run works in hardware interrupt context, which is a prerequisite for
NOHZ_FULL.

Implement:
 - arch_irq_work_raise()
 - arch_irq_work_has_interrupt()

Reviewed-by: Guo Ren <guoren@kernel.org>
Signed-off-by: Huacai Chen <chenhuacai@loongson.cn>
2024-07-20 22:40:58 +08:00
Bibo Mao 03779999ac LoongArch: KVM: Add PV steal time support in guest side
Per-cpu struct kvm_steal_time is added here, its size is 64 bytes and
also defined as 64 bytes, so that the whole structure is in one physical
page.

When a VCPU is online, function pv_enable_steal_time() is called. This
function will pass guest physical address of struct kvm_steal_time and
tells hypervisor to enable steal time. When a vcpu is offline, physical
address is set as 0 and tells hypervisor to disable steal time.

Here is an output of vmstat on guest when there is workload on both host
and guest. It shows steal time stat information.

procs -----------memory---------- -----io---- -system-- ------cpu-----
 r  b   swpd   free  inact active   bi    bo   in   cs us sy id wa st
15  1      0 7583616 184112  72208    20    0  162   52 31  6 43  0 20
17  0      0 7583616 184704  72192    0     0 6318 6885  5 60  8  5 22
16  0      0 7583616 185392  72144    0     0 1766 1081  0 49  0  1 50
16  0      0 7583616 184816  72304    0     0 6300 6166  4 62 12  2 20
18  0      0 7583632 184480  72240    0     0 2814 1754  2 58  4  1 35

Signed-off-by: Bibo Mao <maobibo@loongson.cn>
Signed-off-by: Huacai Chen <chenhuacai@loongson.cn>
2024-07-09 16:25:51 +08:00
Bibo Mao 74c16b2e2b LoongArch: KVM: Add PV IPI support on guest side
PARAVIRT config option and PV IPI is added for the guest side, function
pv_ipi_init() is used to add IPI sending and IPI receiving hooks. This
function firstly checks whether system runs in VM mode, and if kernel
runs in VM mode, it will call function kvm_para_available() to detect
the current hypervirsor type (now only KVM type detection is supported).
The paravirt functions can work only if current hypervisor type is KVM,
since there is only KVM supported on LoongArch now.

PV IPI uses virtual IPI sender and virtual IPI receiver functions. With
virtual IPI sender, IPI message is stored in memory rather than emulated
HW. IPI multicast is also supported, and 128 vcpus can received IPIs
at the same time like X86 KVM method. Hypercall method is used for IPI
sending.

With virtual IPI receiver, HW SWI0 is used rather than real IPI HW.
Since VCPU has separate HW SWI0 like HW timer, there is no trap in IPI
interrupt acknowledge. Since IPI message is stored in memory, there is
no trap in getting IPI message.

Signed-off-by: Bibo Mao <maobibo@loongson.cn>
Signed-off-by: Huacai Chen <chenhuacai@loongson.cn>
2024-05-06 22:00:47 +08:00