Commit Graph

225 Commits

Author SHA1 Message Date
Bibo Mao
5a873d77ba LoongArch: KVM: Move unconditional delay into timer clear scenery
When timer interrupt arrives in guest kernel, guest kernel clears the
timer interrupt and program timer with the next incoming event.

During this stage, timer tick is -1 and timer interrupt status is
disabled in ESTAT register. KVM hypervisor need write zero with timer
tick register and wait timer interrupt injection from HW side, and
then clear timer interrupt.

So there is 2 cycle delay in KVM hypervisor to emulate such scenery,
and the delay is unnecessary if there is no need to clear the timer
interrupt.

Here move 2 cycle delay into timer clear scenery and add timer ESTAT
checking after delay, and set max timer expire value if timer interrupt
does not arrive still.

Cc: stable@vger.kernel.org
Signed-off-by: Bibo Mao <maobibo@loongson.cn>
Signed-off-by: Huacai Chen <chenhuacai@loongson.cn>
2026-05-04 09:00:48 +08:00
Bibo Mao
2433f3f572 LoongArch: KVM: Fix HW timer interrupt lost when inject interrupt by software
With passthrough HW timer, timer interrupt is injected by HW. When
inject emulated CPU interrupt by software such SIP0/SIP1/IPI, HW timer
interrupt may be lost.

Here check whether there is timer tick value inversion before and after
injecting emulated CPU interrupt by software, timer enabling by reading
timer cfg register is skipped. If the timer tick value is detected with
changing, then timer should be enabled. And inject a timer interrupt by
software if there is.

Cc: <stable@vger.kernel.org>
Fixes: f45ad5b8aa ("LoongArch: KVM: Implement vcpu interrupt operations").
Signed-off-by: Bibo Mao <maobibo@loongson.cn>
Signed-off-by: Huacai Chen <chenhuacai@loongson.cn>
2026-05-04 09:00:48 +08:00
Bibo Mao
6debfff785 LoongArch: KVM: Move AVEC interrupt injection into switch loop
When AVEC interrupt controller is emulated in user space, AVEC interrupt
is injected by software like SIP0/SIP1/TI/IPI interrupts. Here also move
the AVEC interrupt injection in switch loop.

Cc: stable@vger.kernel.org
Signed-off-by: Bibo Mao <maobibo@loongson.cn>
Signed-off-by: Huacai Chen <chenhuacai@loongson.cn>
2026-05-04 09:00:48 +08:00
Tao Cui
81e18777d6 LoongArch: KVM: Use kvm_set_pte() in kvm_flush_pte()
kvm_flush_pte() is the only caller that directly assigns *pte instead
of using the kvm_set_pte() wrapper. Use the wrapper for consistency with
the rest of the file.

No functional change intended.

Cc: stable@vger.kernel.org
Reviewed-by: Bibo Mao <maobibo@loongson.cn>
Signed-off-by: Tao Cui <cuitao@kylinos.cn>
Signed-off-by: Huacai Chen <chenhuacai@loongson.cn>
2026-05-04 09:00:38 +08:00
Tao Cui
f26faae96c LoongArch: KVM: Fix missing EMULATE_FAIL in kvm_emu_mmio_read()
In the ldptr (0x24...0x27) opcode decoding path, the default case only
breaks out but without setting "ret" value to EMULATE_FAIL. This leaves
run->mmio.len uninitialized (stale from a previous MMIO operation) while
"ret" value remains EMULATE_DO_MMIO, causing the code to proceed with an
incorrect MMIO length.

Add "ret = EMULATE_FAIL" to match the other default branches in the same
function (e.g. the 0x28...0x2e and 0x38 cases).

Cc: stable@vger.kernel.org
Reviewed-by: Bibo Mao <maobibo@loongson.cn>
Signed-off-by: Tao Cui <cuitao@kylinos.cn>
Signed-off-by: Huacai Chen <chenhuacai@loongson.cn>
2026-05-04 09:00:38 +08:00
Qiang Ma
b3e31a6650 LoongArch: KVM: Cap KVM_CAP_NR_VCPUS by KVM_CAP_MAX_VCPUS
It doesn't make sense to return the recommended maximum number of vCPUs
which exceeds the maximum possible number of vCPUs.

Other architectures have already done this, such as commit 57a2e13ebd
("KVM: MIPS: Cap KVM_CAP_NR_VCPUS by KVM_CAP_MAX_VCPUS")

Cc: stable@vger.kernel.org
Reviewed-by: Bibo Mao <maobibo@loongson.cn>
Signed-off-by: Qiang Ma <maqianga@uniontech.com>
Signed-off-by: Huacai Chen <chenhuacai@loongson.cn>
2026-05-04 09:00:37 +08:00
Xianglai Li
b323a441da LoongArch: KVM: Fix "unreliable stack" for kvm_exc_entry
Insert the appropriate UNWIND hint into the kvm_exc_entry assembly
function to guide the generation of correct ORC table entries, thereby
solving the timeout problem ("unreliable stack") while loading the
livepatch-sample module on a physical machine running virtual machines
with multiple vcpus.

Cc: stable@vger.kernel.org
Signed-off-by: Xianglai Li <lixianglai@loongson.cn>
Signed-off-by: Huacai Chen <chenhuacai@loongson.cn>
2026-05-04 09:00:37 +08:00
Xianglai Li
5203012fa6 LoongArch: KVM: Compile switch.S directly into the kernel
If we directly compile the switch.S file into the kernel, the address of
the kvm_exc_entry function will definitely be within the DMW memory area.
Therefore, we will no longer need to perform a copy relocation of the
kvm_exc_entry.

So this patch compiles switch.S directly into the kernel, and then remove
the copy relocation execution logic for the kvm_exc_entry function.

Cc: stable@vger.kernel.org
Signed-off-by: Xianglai Li <lixianglai@loongson.cn>
Signed-off-by: Huacai Chen <chenhuacai@loongson.cn>
2026-05-04 09:00:37 +08:00
Linus Torvalds
ff57d59200 LoongArch changes for v7.1
1, Adjust build infrastructure for 32BIT/64BIT;
 2, Add HIGHMEM (PKMAP and FIX_KMAP) support;
 3, Show and handle CPU vulnerabilites correctly;
 4, Batch the icache maintenance for jump_label;
 5, Add more atomic instructions support for BPF JIT;
 6, Add more features (e.g. fsession) support for BPF trampoline;
 7, Some bug fixes and other small changes.
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Merge tag 'loongarch-7.1' of git://git.kernel.org/pub/scm/linux/kernel/git/chenhuacai/linux-loongson

Pull LoongArch updates from Huacai Chen:

 - Adjust build infrastructure for 32BIT/64BIT

 - Add HIGHMEM (PKMAP and FIX_KMAP) support

 - Show and handle CPU vulnerabilites correctly

 - Batch the icache maintenance for jump_label

 - Add more atomic instructions support for BPF JIT

 - Add more features (e.g. fsession) support for BPF trampoline

 - Some bug fixes and other small changes

* tag 'loongarch-7.1' of git://git.kernel.org/pub/scm/linux/kernel/git/chenhuacai/linux-loongson: (21 commits)
  selftests/bpf: Enable CAN_USE_LOAD_ACQ_STORE_REL for LoongArch
  LoongArch: BPF: Add fsession support for trampolines
  LoongArch: BPF: Introduce emit_store_stack_imm64() helper
  LoongArch: BPF: Support up to 12 function arguments for trampoline
  LoongArch: BPF: Support small struct arguments for trampoline
  LoongArch: BPF: Open code and remove invoke_bpf_mod_ret()
  LoongArch: BPF: Support load-acquire and store-release instructions
  LoongArch: BPF: Support 8 and 16 bit read-modify-write instructions
  LoongArch: BPF: Add the default case in emit_atomic() and rename it
  LoongArch: Define instruction formats for AM{SWAP/ADD}.{B/H} and DBAR
  LoongArch: Batch the icache maintenance for jump_label
  LoongArch: Add flush_icache_all()/local_flush_icache_all()
  LoongArch: Add spectre boundry for syscall dispatch table
  LoongArch: Show CPU vulnerabilites correctly
  LoongArch: Make arch_irq_work_has_interrupt() true only if IPI HW exist
  LoongArch: Use get_random_canary() for stack canary init
  LoongArch: Improve the logging of disabling KASLR
  LoongArch: Align FPU register state to 32 bytes
  LoongArch: Handle CONFIG_32BIT in syscall_get_arch()
  LoongArch: Add HIGHMEM (PKMAP and FIX_KMAP) support
  ...
2026-04-24 09:54:45 -07:00
Huacai Chen
3d9aba6618 LoongArch: Adjust build infrastructure for 32BIT/64BIT
Adjust build infrastructure (Kconfig, Makefile and ld scripts) to let
us enable both 32BIT/64BIT kernel build.

Reviewed-by: Arnd Bergmann <arnd@arndb.de>
Signed-off-by: Jiaxun Yang <jiaxun.yang@flygoat.com>
Signed-off-by: Huacai Chen <chenhuacai@loongson.cn>
2026-04-22 15:44:26 +08:00
Linus Torvalds
01f492e181 Arm:
- Add support for tracing in the standalone EL2 hypervisor code, which
   should help both debugging and performance analysis.  This uses the
   new infrastructure for 'remote' trace buffers that can be exposed
   by non-kernel entities such as firmware, and which came through the
   tracing tree.
 
 - Add support for GICv5 Per Processor Interrupts (PPIs), as the starting
   point for supporting the new GIC architecture in KVM.
 
 - Finally add support for pKVM protected guests, where pages are unmapped
   from the host as they are faulted into the guest and can be shared back
   from the guest using pKVM hypercalls.  Protected guests are created
   using a new machine type identifier.  As the elusive guestmem has not
   yet delivered on its promises, anonymous memory is also supported.
 
   This is only a first step towards full isolation from the host; for
   example, the CPU register state and DMA accesses are not yet isolated.
   Because this does not really yet bring fully what it promises, it is
   hidden behind CONFIG_ARM_PKVM_GUEST + 'kvm-arm.mode=protected', and
   also triggers TAINT_USER when a VM is created.  Caveat emptor.
 
 - Rework the dreaded user_mem_abort() function to make it more
   maintainable, reducing the amount of state being exposed to the
   various helpers and rendering a substantial amount of state immutable.
 
 - Expand the Stage-2 page table dumper to support NV shadow page tables
   on a per-VM basis.
 
 - Tidy up the pKVM PSCI proxy code to be slightly less hard to follow.
 
 - Fix both SPE and TRBE in non-VHE configurations so that they do not
   generate spurious, out of context table walks that ultimately lead
   to very bad HW lockups.
 
 - A small set of patches fixing the Stage-2 MMU freeing in error cases.
 
 - Tighten-up accepted SMC immediate value to be only #0 for host
   SMCCC calls.
 
 - The usual cleanups and other selftest churn.
 
 LoongArch:
 
 - Use CSR_CRMD_PLV for kvm_arch_vcpu_in_kernel().
 
 - Add DMSINTC irqchip in kernel support.
 
 RISC-V:
 
 - Fix steal time shared memory alignment checks
 
 - Fix vector context allocation leak
 
 - Fix array out-of-bounds in pmu_ctr_read() and pmu_fw_ctr_read_hi()
 
 - Fix double-free of sdata in kvm_pmu_clear_snapshot_area()
 
 - Fix integer overflow in kvm_pmu_validate_counter_mask()
 
 - Fix shift-out-of-bounds in make_xfence_request()
 
 - Fix lost write protection on huge pages during dirty logging
 
 - Split huge pages during fault handling for dirty logging
 
 - Skip CSR restore if VCPU is reloaded on the same core
 
 - Implement kvm_arch_has_default_irqchip() for KVM selftests
 
 - Factored-out ISA checks into separate sources
 
 - Added hideleg to struct kvm_vcpu_config
 
 - Factored-out VCPU config into separate sources
 
 - Support configuration of per-VM HGATP mode from KVM user space
 
 s390:
 
 - Support for ESA (31-bit) guests inside nested hypervisors.
 
 - Remove restriction on memslot alignment, which is not needed anymore with
   the new gmap code.
 
 - Fix LPSW/E to update the bear (which of course is the breaking event
   address register).
 
 x86:
 
 - Shut up various UBSAN warnings on reading module parameter before they
   were initialized.
 
 - Don't zero-allocate page tables that are used for splitting hugepages in
   the TDP MMU, as KVM is guaranteed to set all SPTEs in the page table and
   thus write all bytes.
 
 - As an optimization, bail early when trying to unsync 4KiB mappings if the
   target gfn can just be mapped with a 2MiB hugepage.
 
 x86 generic:
 
 - Copy single-chunk MMIO write values into struct kvm_vcpu (more precisely
   struct kvm_mmio_fragment) to fix use-after-free stack bugs where KVM
   would dereference stack pointer after an exit to userspace.
 
 - Clean up and comment the emulated MMIO code to try to make it easier to
   maintain (not necessarily "easy", but "easier").
 
 - Move VMXON+VMXOFF and EFER.SVME toggling out of KVM (not *all* of VMX
   and SVM enabling) as it is needed for trusted I/O.
 
 - Advertise support for AVX512 Bit Matrix Multiply (BMM) instructions
 
 - Immediately fail the build if a required #define is missing in one of
   KVM's headers that is included multiple times.
 
 - Reject SET_GUEST_DEBUG with -EBUSY if there's an already injected
   exception, mostly to prevent syzkaller from abusing the uAPI to
   trigger WARNs, but also because it can help prevent userspace from
   unintentionally crashing the VM.
 
 - Exempt SMM from CPUID faulting on Intel, as per the spec.
 
 - Misc hardening and cleanup changes.
 
 x86 (AMD):
 
 - Fix and optimize IRQ window inhibit handling for AVIC; make it per-vCPU
   so that KVM doesn't prematurely re-enable AVIC if multiple
   vCPUs have to-be-injected IRQs.
 
 - Clean up and optimize the OSVW handling, avoiding a bug in which KVM would
   overwrite state when enabling virtualization on multiple CPUs in parallel.
   This should not be a problem because OSVW should usually be the same for
   all CPUs.
 
 - Drop a WARN in KVM_MEMORY_ENCRYPT_REG_REGION where KVM complains about a
   "too large" size based purely on user input.
 
 - Clean up and harden the pinning code for KVM_MEMORY_ENCRYPT_REG_REGION.
 
 - Disallow synchronizing a VMSA of an already-launched/encrypted vCPU, as
   doing so for an SNP guest will crash the host due to an RMP violation
   page fault.
 
 - Overhaul KVM's APIs for detecting SEV+ guests so that VM-scoped queries
   are required to hold kvm->lock, and enforce it by lockdep.  Fix various
   bugs where sev_guest() was not ensured to be stable for the whole
   duration of a function or ioctl.
 
 - Convert a pile of kvm->lock SEV code to guard().
 
 - Play nicer with userspace that does not enable KVM_CAP_EXCEPTION_PAYLOAD,
   for which KVM needs to set CR2 and DR6 as a response to ioctls such as
   KVM_GET_VCPU_EVENTS (even if the payload would end up in EXITINFO2
   rather than CR2, for example).  Only set CR2 and DR6 when consumption of
   the payload is imminent, but on the other hand force delivery of the
   payload in all paths where userspace retrieves CR2 or DR6.
 
 - Use vcpu->arch.cr2 when updating vmcb12's CR2 on nested #VMEXIT instead
   of vmcb02->save.cr2.  The value is out of sync after a save/restore
   or after a #PF is injected into L2.
 
 - Fix a class of nSVM bugs where some fields written by the CPU are not
   synchronized from vmcb02 to cached vmcb12 after VMRUN, and so are not
   up-to-date when saved by KVM_GET_NESTED_STATE.
 
 - Fix a class of bugs where the ordering between KVM_SET_NESTED_STATE and
   KVM_SET_{S}REGS could cause vmcb02 to be incorrectly initialized after
   save+restore.
 
 - Add a variety of missing nSVM consistency checks.
 
 - Fix several bugs where KVM failed to correctly update VMCB fields on
   nested #VMEXIT.
 
 - Fix several bugs where KVM failed to correctly synthesize #UD or #GP for
   SVM-related instructions.
 
 - Add support for save+restore of virtualized LBRs (on SVM).
 
 - Refactor various helpers and macros to improve clarity and (hopefully)
   make the code easier to maintain.
 
 - Aggressively sanitize fields when copying from vmcb12, to guard against
   unintentionally allowing L1 to utilize yet-to-be-defined features.
 
 - Fix several bugs where KVM botched rAX legality checks when emulating SVM
   instructions.  There are remaining issues in that KVM doesn't handle size
   prefix overrides for 64-bit guests.
 
 - Fail emulation of VMRUN/VMLOAD/VMSAVE if mapping vmcb12 fails instead of
   somewhat arbitrarily synthesizing #GP (i.e. don't double down on AMD's
   architectural but sketchy behavior of generating #GP for "unsupported"
   addresses).
 
 - Cache all used vmcb12 fields to further harden against TOCTOU bugs.
 
 x86 (Intel):
 
 - Drop obsolete branch hint prefixes from the VMX instruction macros.
 
 - Use ASM_INPUT_RM() in __vmcs_writel() to coerce clang into using a
   register input when appropriate.
 
 - Code cleanups.
 
 guest_memfd:
 
 - Don't mark guest_memfd folios as accessed, as guest_memfd doesn't support
   reclaim, the memory is unevictable, and there is no storage to write
   back to.
 
 LoongArch selftests:
 
 - Add KVM PMU test cases
 
 s390 selftests:
 
 - Enable more memory selftests.
 
 x86 selftests:
 
 - Add support for Hygon CPUs in KVM selftests.
 
 - Fix a bug in the MSR test where it would get false failures on AMD/Hygon
   CPUs with exactly one of RDPID or RDTSCP.
 
 - Add an MADV_COLLAPSE testcase for guest_memfd as a regression test for a
   bug where the kernel would attempt to collapse guest_memfd folios against
   KVM's will.
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Merge tag 'for-linus' of git://git.kernel.org/pub/scm/virt/kvm/kvm

Pull kvm updates from Paolo Bonzini:
 "Arm:

   - Add support for tracing in the standalone EL2 hypervisor code,
     which should help both debugging and performance analysis. This
     uses the new infrastructure for 'remote' trace buffers that can be
     exposed by non-kernel entities such as firmware, and which came
     through the tracing tree

   - Add support for GICv5 Per Processor Interrupts (PPIs), as the
     starting point for supporting the new GIC architecture in KVM

   - Finally add support for pKVM protected guests, where pages are
     unmapped from the host as they are faulted into the guest and can
     be shared back from the guest using pKVM hypercalls. Protected
     guests are created using a new machine type identifier. As the
     elusive guestmem has not yet delivered on its promises, anonymous
     memory is also supported

     This is only a first step towards full isolation from the host; for
     example, the CPU register state and DMA accesses are not yet
     isolated. Because this does not really yet bring fully what it
     promises, it is hidden behind CONFIG_ARM_PKVM_GUEST +
     'kvm-arm.mode=protected', and also triggers TAINT_USER when a VM is
     created. Caveat emptor

   - Rework the dreaded user_mem_abort() function to make it more
     maintainable, reducing the amount of state being exposed to the
     various helpers and rendering a substantial amount of state
     immutable

   - Expand the Stage-2 page table dumper to support NV shadow page
     tables on a per-VM basis

   - Tidy up the pKVM PSCI proxy code to be slightly less hard to
     follow

   - Fix both SPE and TRBE in non-VHE configurations so that they do not
     generate spurious, out of context table walks that ultimately lead
     to very bad HW lockups

   - A small set of patches fixing the Stage-2 MMU freeing in error
     cases

   - Tighten-up accepted SMC immediate value to be only #0 for host
     SMCCC calls

   - The usual cleanups and other selftest churn

  LoongArch:

   - Use CSR_CRMD_PLV for kvm_arch_vcpu_in_kernel()

   - Add DMSINTC irqchip in kernel support

  RISC-V:

   - Fix steal time shared memory alignment checks

   - Fix vector context allocation leak

   - Fix array out-of-bounds in pmu_ctr_read() and pmu_fw_ctr_read_hi()

   - Fix double-free of sdata in kvm_pmu_clear_snapshot_area()

   - Fix integer overflow in kvm_pmu_validate_counter_mask()

   - Fix shift-out-of-bounds in make_xfence_request()

   - Fix lost write protection on huge pages during dirty logging

   - Split huge pages during fault handling for dirty logging

   - Skip CSR restore if VCPU is reloaded on the same core

   - Implement kvm_arch_has_default_irqchip() for KVM selftests

   - Factored-out ISA checks into separate sources

   - Added hideleg to struct kvm_vcpu_config

   - Factored-out VCPU config into separate sources

   - Support configuration of per-VM HGATP mode from KVM user space

  s390:

   - Support for ESA (31-bit) guests inside nested hypervisors

   - Remove restriction on memslot alignment, which is not needed
     anymore with the new gmap code

   - Fix LPSW/E to update the bear (which of course is the breaking
     event address register)

  x86:

   - Shut up various UBSAN warnings on reading module parameter before
     they were initialized

   - Don't zero-allocate page tables that are used for splitting
     hugepages in the TDP MMU, as KVM is guaranteed to set all SPTEs in
     the page table and thus write all bytes

   - As an optimization, bail early when trying to unsync 4KiB mappings
     if the target gfn can just be mapped with a 2MiB hugepage

  x86 generic:

   - Copy single-chunk MMIO write values into struct kvm_vcpu (more
     precisely struct kvm_mmio_fragment) to fix use-after-free stack
     bugs where KVM would dereference stack pointer after an exit to
     userspace

   - Clean up and comment the emulated MMIO code to try to make it
     easier to maintain (not necessarily "easy", but "easier")

   - Move VMXON+VMXOFF and EFER.SVME toggling out of KVM (not *all* of
     VMX and SVM enabling) as it is needed for trusted I/O

   - Advertise support for AVX512 Bit Matrix Multiply (BMM) instructions

   - Immediately fail the build if a required #define is missing in one
     of KVM's headers that is included multiple times

   - Reject SET_GUEST_DEBUG with -EBUSY if there's an already injected
     exception, mostly to prevent syzkaller from abusing the uAPI to
     trigger WARNs, but also because it can help prevent userspace from
     unintentionally crashing the VM

   - Exempt SMM from CPUID faulting on Intel, as per the spec

   - Misc hardening and cleanup changes

  x86 (AMD):

   - Fix and optimize IRQ window inhibit handling for AVIC; make it
     per-vCPU so that KVM doesn't prematurely re-enable AVIC if multiple
     vCPUs have to-be-injected IRQs

   - Clean up and optimize the OSVW handling, avoiding a bug in which
     KVM would overwrite state when enabling virtualization on multiple
     CPUs in parallel. This should not be a problem because OSVW should
     usually be the same for all CPUs

   - Drop a WARN in KVM_MEMORY_ENCRYPT_REG_REGION where KVM complains
     about a "too large" size based purely on user input

   - Clean up and harden the pinning code for KVM_MEMORY_ENCRYPT_REG_REGION

   - Disallow synchronizing a VMSA of an already-launched/encrypted
     vCPU, as doing so for an SNP guest will crash the host due to an
     RMP violation page fault

   - Overhaul KVM's APIs for detecting SEV+ guests so that VM-scoped
     queries are required to hold kvm->lock, and enforce it by lockdep.
     Fix various bugs where sev_guest() was not ensured to be stable for
     the whole duration of a function or ioctl

   - Convert a pile of kvm->lock SEV code to guard()

   - Play nicer with userspace that does not enable
     KVM_CAP_EXCEPTION_PAYLOAD, for which KVM needs to set CR2 and DR6
     as a response to ioctls such as KVM_GET_VCPU_EVENTS (even if the
     payload would end up in EXITINFO2 rather than CR2, for example).
     Only set CR2 and DR6 when consumption of the payload is imminent,
     but on the other hand force delivery of the payload in all paths
     where userspace retrieves CR2 or DR6

   - Use vcpu->arch.cr2 when updating vmcb12's CR2 on nested #VMEXIT
     instead of vmcb02->save.cr2. The value is out of sync after a
     save/restore or after a #PF is injected into L2

   - Fix a class of nSVM bugs where some fields written by the CPU are
     not synchronized from vmcb02 to cached vmcb12 after VMRUN, and so
     are not up-to-date when saved by KVM_GET_NESTED_STATE

   - Fix a class of bugs where the ordering between KVM_SET_NESTED_STATE
     and KVM_SET_{S}REGS could cause vmcb02 to be incorrectly
     initialized after save+restore

   - Add a variety of missing nSVM consistency checks

   - Fix several bugs where KVM failed to correctly update VMCB fields
     on nested #VMEXIT

   - Fix several bugs where KVM failed to correctly synthesize #UD or
     #GP for SVM-related instructions

   - Add support for save+restore of virtualized LBRs (on SVM)

   - Refactor various helpers and macros to improve clarity and
     (hopefully) make the code easier to maintain

   - Aggressively sanitize fields when copying from vmcb12, to guard
     against unintentionally allowing L1 to utilize yet-to-be-defined
     features

   - Fix several bugs where KVM botched rAX legality checks when
     emulating SVM instructions. There are remaining issues in that KVM
     doesn't handle size prefix overrides for 64-bit guests

   - Fail emulation of VMRUN/VMLOAD/VMSAVE if mapping vmcb12 fails
     instead of somewhat arbitrarily synthesizing #GP (i.e. don't double
     down on AMD's architectural but sketchy behavior of generating #GP
     for "unsupported" addresses)

   - Cache all used vmcb12 fields to further harden against TOCTOU bugs

  x86 (Intel):

   - Drop obsolete branch hint prefixes from the VMX instruction macros

   - Use ASM_INPUT_RM() in __vmcs_writel() to coerce clang into using a
     register input when appropriate

   - Code cleanups

  guest_memfd:

   - Don't mark guest_memfd folios as accessed, as guest_memfd doesn't
     support reclaim, the memory is unevictable, and there is no storage
     to write back to

  LoongArch selftests:

   - Add KVM PMU test cases

  s390 selftests:

   - Enable more memory selftests

  x86 selftests:

   - Add support for Hygon CPUs in KVM selftests

   - Fix a bug in the MSR test where it would get false failures on
     AMD/Hygon CPUs with exactly one of RDPID or RDTSCP

   - Add an MADV_COLLAPSE testcase for guest_memfd as a regression test
     for a bug where the kernel would attempt to collapse guest_memfd
     folios against KVM's will"

* tag 'for-linus' of git://git.kernel.org/pub/scm/virt/kvm/kvm: (373 commits)
  KVM: x86: use inlines instead of macros for is_sev_*guest
  x86/virt: Treat SVM as unsupported when running as an SEV+ guest
  KVM: SEV: Goto an existing error label if charging misc_cg for an ASID fails
  KVM: SVM: Move lock-protected allocation of SEV ASID into a separate helper
  KVM: SEV: use mutex guard in snp_handle_guest_req()
  KVM: SEV: use mutex guard in sev_mem_enc_unregister_region()
  KVM: SEV: use mutex guard in sev_mem_enc_ioctl()
  KVM: SEV: use mutex guard in snp_launch_update()
  KVM: SEV: Assert that kvm->lock is held when querying SEV+ support
  KVM: SEV: Document that checking for SEV+ guests when reclaiming memory is "safe"
  KVM: SEV: Hide "struct kvm_sev_info" behind CONFIG_KVM_AMD_SEV=y
  KVM: SEV: WARN on unhandled VM type when initializing VM
  KVM: LoongArch: selftests: Add PMU overflow interrupt test
  KVM: LoongArch: selftests: Add basic PMU event counting test
  KVM: LoongArch: selftests: Add cpucfg read/write helpers
  LoongArch: KVM: Add DMSINTC inject msi to vCPU
  LoongArch: KVM: Add DMSINTC device support
  LoongArch: KVM: Make vcpu_is_preempted() as a macro rather than function
  LoongArch: KVM: Move host CSR_GSTAT save and restore in context switch
  LoongArch: KVM: Move host CSR_EENTRY save and restore in context switch
  ...
2026-04-17 07:18:03 -07:00
Linus Torvalds
a970ed1881 bitmap updates for v7.1
- new API: bitmap_weight_from() and bitmap_weighted_xor() (Yury);
  - drop unused __find_nth_andnot_bit() (Yury);
  - new tests and test improvements (Andy, Akinobu, Yury);
  - fixes for count_zeroes API (Yury);
  - cleanup bitmap_print_to_pagebuf() mess (Yury);
  - documentation updates (Andy, Kai, Kit).
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Merge tag 'bitmap-for-v7.1' of https://github.com/norov/linux

Pull bitmap updates from Yury Norov:

 - new API: bitmap_weight_from() and bitmap_weighted_xor() (Yury)

 - drop unused __find_nth_andnot_bit() (Yury)

 - new tests and test improvements (Andy, Akinobu, Yury)

 - fixes for count_zeroes API (Yury)

 - cleanup bitmap_print_to_pagebuf() mess (Yury)

 - documentation updates (Andy, Kai, Kit).

* tag 'bitmap-for-v7.1' of https://github.com/norov/linux: (24 commits)
  bitops: Update kernel-doc for sign_extendXX()
  powerpc/xive: simplify xive_spapr_debug_show()
  thermal: intel: switch cpumask_get() to using cpumask_print_to_pagebuf()
  coresight: don't use bitmap_print_to_pagebuf()
  lib/prime_numbers: drop temporary buffer in dump_primes()
  drm/xe: switch xe_pagefault_queue_init() to using bitmap_weighted_or()
  ice: use bitmap_empty() in ice_vf_has_no_qs_ena
  ice: use bitmap_weighted_xor() in ice_find_free_recp_res_idx()
  bitmap: introduce bitmap_weighted_xor()
  bitmap: add test_zero_nbits()
  bitmap: exclude nbits == 0 cases from bitmap test
  bitmap: test bitmap_weight() for more
  asm-generic/bitops: Fix a comment typo in instrumented-atomic.h
  bitops: fix kernel-doc parameter name for parity8()
  lib: count_zeros: unify count_{leading,trailing}_zeros()
  lib: count_zeros: fix 32/64-bit inconsistency in count_trailing_zeros()
  lib: crypto: fix comments for count_leading_zeros()
  x86/topology: use bitmap_weight_from()
  bitmap: add bitmap_weight_from()
  lib/find_bit_benchmark: avoid clearing randomly filled bitmap in test_find_first_bit()
  ...
2026-04-14 08:55:18 -07:00
Song Gao
03de5eecb0 LoongArch: KVM: Add DMSINTC inject msi to vCPU
Implement irqfd that deliver msi to vCPU and vCPU dmsintc irq injection.
Add pch_msi_set_irq() choice dmsintc to set msi irq by the msg_addr and
implement dmsintc set msi irq.

Signed-off-by: Song Gao <gaosong@loongson.cn>
Signed-off-by: Huacai Chen <chenhuacai@loongson.cn>
2026-04-09 18:56:37 +08:00
Song Gao
229132c309 LoongArch: KVM: Add DMSINTC device support
Add device model for DMSINTC interrupt controller, implement basic
create/destroy/set_attr interfaces, and register device model to kvm
device table.

Reviewed-by: Bibo Mao <maobibo@loongson.cn>
Signed-off-by: Song Gao <gaosong@loongson.cn>
Signed-off-by: Huacai Chen <chenhuacai@loongson.cn>
2026-04-09 18:56:37 +08:00
Bibo Mao
aac656857e LoongArch: KVM: Move host CSR_GSTAT save and restore in context switch
CSR register LOONGARCH_CSR_GSTAT stores guest VMID information. With
existing implementation method, VMID is per vCPU, similar with ASID in
kernel. LOONGARCH_CSR_GSTAT is written at VM entry even if VMID is not
changed.

Here move LOONGARCH_CSR_GSTAT save/restore in vCPU context switch, and
update LOONGARCH_CSR_GSTAT only when VMID is updated at VM entry. At
most time VM enter/exit is much more frequent than vCPU thread context
switch.

Signed-off-by: Bibo Mao <maobibo@loongson.cn>
Signed-off-by: Huacai Chen <chenhuacai@loongson.cn>
2026-04-09 18:56:36 +08:00
Bibo Mao
f62eb9ca8d LoongArch: KVM: Move host CSR_EENTRY save and restore in context switch
CSR register LOONGARCH_CSR_EENTRY is shared between host CPU and guest
vCPU, KVM need save and restore LOONGARCH_CSR_EENTRY register. Here move
LOONGARCH_CSR_EENTRY saving in to context switch function rather than VM
entry.

At most time VM enter/exit is much more frequent than vCPU thread context
switch.

Signed-off-by: Bibo Mao <maobibo@loongson.cn>
Signed-off-by: Huacai Chen <chenhuacai@loongson.cn>
2026-04-09 18:56:36 +08:00
Bibo Mao
14d2714d65 LoongArch: KVM: Check kvm_request_pending() in kvm_late_check_requests()
Add kvm_request_pending() checking firstly in kvm_late_check_requests(),
at most time there is no pending request, then the following pending bit
checking can be skipped.

Also embed function kvm_check_pmu() in to kvm_late_check_requests(), and
put it after the kvm_request_pending() checking.

Signed-off-by: Bibo Mao <maobibo@loongson.cn>
Signed-off-by: Huacai Chen <chenhuacai@loongson.cn>
2026-04-09 18:56:36 +08:00
Tao Cui
da773ea3f5 LoongArch: KVM: Use CSR_CRMD_PLV in kvm_arch_vcpu_in_kernel()
The function reads LOONGARCH_CSR_CRMD but uses CSR_PRMD_PPLV to
extract the privilege level. While both masks have the same value
(0x3), CSR_CRMD_PLV is the semantically correct constant for CRMD.

Cc: stable@vger.kernel.org
Reviewed-by: Bibo Mao <maobibo@loongson.cn>
Signed-off-by: Tao Cui <cuitao@kylinos.cn>
Signed-off-by: Huacai Chen <chenhuacai@loongson.cn>
2026-04-09 18:56:36 +08:00
Bibo Mao
6bcfb7f46d LoongArch: KVM: Fix base address calculation in kvm_eiointc_regs_access()
In function kvm_eiointc_regs_access(), the register base address is
caculated from array base address plus offset, the offset is absolute
value from the base address. The data type of array base address is
u64, it should be converted into the "void *" type and then plus the
offset.

Cc: <stable@vger.kernel.org>
Fixes: d3e43a1f34 ("LoongArch: KVM: Use 64-bit register definition for EIOINTC").
Reported-by: Aurelien Jarno <aurel32@debian.org>
Link: https://bugs.debian.org/cgi-bin/bugreport.cgi?bug=1131431
Signed-off-by: Bibo Mao <maobibo@loongson.cn>
Signed-off-by: Huacai Chen <chenhuacai@loongson.cn>
2026-03-26 14:29:09 +08:00
Huacai Chen
b97bd69eb0 LoongArch: KVM: Handle the case that EIOINTC's coremap is empty
EIOINTC's coremap in eiointc_update_sw_coremap() can be empty, currently
we get a cpuid with -1 in this case, but we actually need 0 because it's
similar as the case that cpuid >= 4.

This fix an out-of-bounds access to kvm_arch::phyid_map::phys_map[].

Cc: <stable@vger.kernel.org>
Fixes: 3956a52bc0 ("LoongArch: KVM: Add EIOINTC read and write functions")
Reported-by: Aurelien Jarno <aurel32@debian.org>
Link: https://bugs.debian.org/cgi-bin/bugreport.cgi?bug=1131431
Signed-off-by: Huacai Chen <chenhuacai@loongson.cn>
2026-03-26 14:29:09 +08:00
Huacai Chen
2db06c15d8 LoongArch: KVM: Make kvm_get_vcpu_by_cpuid() more robust
kvm_get_vcpu_by_cpuid() takes a cpuid parameter whose type is int, so
cpuid can be negative. Let kvm_get_vcpu_by_cpuid() return NULL for this
case so as to make it more robust.

This fix an out-of-bounds access to kvm_arch::phyid_map::phys_map[].

Cc: <stable@vger.kernel.org>
Fixes: 73516e9da5 ("LoongArch: KVM: Add vcpu mapping from physical cpuid")
Reported-by: Aurelien Jarno <aurel32@debian.org>
Link: https://bugs.debian.org/cgi-bin/bugreport.cgi?bug=1131431
Signed-off-by: Huacai Chen <chenhuacai@loongson.cn>
2026-03-26 14:29:09 +08:00
Yury Norov
be56db15fc lib: count_zeros: unify count_{leading,trailing}_zeros()
The 'leading' helper returns BITS_PER_LONG if x == 0, while 'trailing'
one returns COUNT_TRAILING_ZEROS_0, which turns to be -1.

None of the current users explicitly check the returned value for
COUNT_TRAILING_ZEROS_0, except the loongarch, which tests implicitly
for the '>= 0'.

So, align count_trailing_zeros() with the count_leading_zeros(), and
simplify the loongarch handling.

Reviewed-by: Andy Shevchenko <andriy.shevchenko@intel.com>
Signed-off-by: Yury Norov <ynorov@nvidia.com>
2026-03-23 13:33:51 -04:00
Bibo Mao
c252c12d1f LoongArch: KVM: Fix typo issue in kvm_vm_init_features()
Most of VM feature detections are integer OR operations, and integer
assignment operation will clear previous integer OR operation. So here
change all integer assignment operations to integer OR operations.

Fixes: 82db90bf46 ("LoongArch: KVM: Move feature detection in kvm_vm_init_features()")
Signed-off-by: Bibo Mao <maobibo@loongson.cn>
Signed-off-by: Huacai Chen <chenhuacai@loongson.cn>
2026-03-16 10:36:02 +08:00
Paolo Bonzini
94fe3e6515 KVM generic changes for 7.0
- Remove a subtle pseudo-overlay of kvm_stats_desc, which, aside from being
    unnecessary and confusing, triggered compiler warnings due to
    -Wflex-array-member-not-at-end.
 
  - Document that vcpu->mutex is take outside of kvm->slots_lock and
    kvm->slots_arch_lock, which is intentional and desirable despite being
    rather unintuitive.
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Merge tag 'kvm-x86-generic-7.0-rc3' of https://github.com/kvm-x86/linux into HEAD

KVM generic changes for 7.0

 - Remove a subtle pseudo-overlay of kvm_stats_desc, which, aside from being
   unnecessary and confusing, triggered compiler warnings due to
   -Wflex-array-member-not-at-end.

 - Document that vcpu->mutex is take outside of kvm->slots_lock and
   kvm->slots_arch_lock, which is intentional and desirable despite being
   rather unintuitive.
2026-03-11 18:01:55 +01:00
Paolo Bonzini
70295a479d KVM: always define KVM_CAP_SYNC_MMU
KVM_CAP_SYNC_MMU is provided by KVM's MMU notifiers, which are now always
available.  Move the definition from individual architectures to common
code.

Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
2026-02-28 15:31:35 +01:00
Paolo Bonzini
407fd8b8d8 KVM: remove CONFIG_KVM_GENERIC_MMU_NOTIFIER
All architectures now use MMU notifier for KVM page table management.
Remove the Kconfig symbol and the code that is used when it is
disabled.

Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
2026-02-28 15:31:35 +01:00
Linus Torvalds
bf4afc53b7 Convert 'alloc_obj' family to use the new default GFP_KERNEL argument
This was done entirely with mindless brute force, using

    git grep -l '\<k[vmz]*alloc_objs*(.*, GFP_KERNEL)' |
        xargs sed -i 's/\(alloc_objs*(.*\), GFP_KERNEL)/\1)/'

to convert the new alloc_obj() users that had a simple GFP_KERNEL
argument to just drop that argument.

Note that due to the extreme simplicity of the scripting, any slightly
more complex cases spread over multiple lines would not be triggered:
they definitely exist, but this covers the vast bulk of the cases, and
the resulting diff is also then easier to check automatically.

For the same reason the 'flex' versions will be done as a separate
conversion.

Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2026-02-21 17:09:51 -08:00
Kees Cook
69050f8d6d treewide: Replace kmalloc with kmalloc_obj for non-scalar types
This is the result of running the Coccinelle script from
scripts/coccinelle/api/kmalloc_objs.cocci. The script is designed to
avoid scalar types (which need careful case-by-case checking), and
instead replace kmalloc-family calls that allocate struct or union
object instances:

Single allocations:	kmalloc(sizeof(TYPE), ...)
are replaced with:	kmalloc_obj(TYPE, ...)

Array allocations:	kmalloc_array(COUNT, sizeof(TYPE), ...)
are replaced with:	kmalloc_objs(TYPE, COUNT, ...)

Flex array allocations:	kmalloc(struct_size(PTR, FAM, COUNT), ...)
are replaced with:	kmalloc_flex(*PTR, FAM, COUNT, ...)

(where TYPE may also be *VAR)

The resulting allocations no longer return "void *", instead returning
"TYPE *".

Signed-off-by: Kees Cook <kees@kernel.org>
2026-02-21 01:02:28 -08:00
Paolo Bonzini
bf2c3138ae Merge tag 'kvm-x86-pmu-6.20' of https://github.com/kvm-x86/linux into HEAD
KVM mediated PMU support for 6.20

Add support for mediated PMUs, where KVM gives the guest full ownership of PMU
hardware (contexted switched around the fastpath run loop) and allows direct
access to data MSRs and PMCs (restricted by the vPMU model), but intercepts
access to control registers, e.g. to enforce event filtering and to prevent the
guest from profiling sensitive host state.

To keep overall complexity reasonable, mediated PMU usage is all or nothing
for a given instance of KVM (controlled via module param).  The Mediated PMU
is disabled default, partly to maintain backwards compatilibity for existing
setup, partly because there are tradeoffs when running with a mediated PMU that
may be non-starters for some use cases, e.g. the host loses the ability to
profile guests with mediated PMUs, the fastpath run loop is also a blind spot,
entry/exit transitions are more expensive, etc.

Versus the emulated PMU, where KVM is "just another perf user", the mediated
PMU delivers more accurate profiling and monitoring (no risk of contention and
thus dropped events), with significantly less overhead (fewer exits and faster
emulation/programming of event selectors) E.g. when running Specint-2017 on
a single-socket Sapphire Rapids with 56 cores and no-SMT, and using perf from
within the guest:

  Perf command:
  a. basic-sampling: perf record -F 1000 -e 6-instructions  -a --overwrite
  b. multiplex-sampling: perf record -F 1000 -e 10-instructions -a --overwrite

  Guest performance overhead:
  ---------------------------------------------------------------------------
  | Test case          | emulated vPMU | all passthrough | passthrough with |
  |                    |               |                 | event filters    |
  ---------------------------------------------------------------------------
  | basic-sampling     |   33.62%      |    4.24%        |   6.21%          |
  ---------------------------------------------------------------------------
  | multiplex-sampling |   79.32%      |    7.34%        |   10.45%         |
  ---------------------------------------------------------------------------
2026-02-11 12:45:40 -05:00
Bibo Mao
9b486cdd03 LoongArch: KVM: Add paravirt preempt feature in hypervisor side
Feature KVM_FEATURE_PREEMPT is added to show whether vCPU is preempted
or not. It is to help guest OS scheduling or lock checking etc. Here
add KVM_FEATURE_PREEMPT feature and use one byte as preempted flag in
the steal time structure.

Signed-off-by: Bibo Mao <maobibo@loongson.cn>
Signed-off-by: Huacai Chen <chenhuacai@loongson.cn>
2026-02-06 09:28:01 +08:00
Bibo Mao
2faec60a48 LoongArch: KVM: Set default return value in KVM IO bus ops
When in-kernel irqchip is enabled, its register area is registered in
the KVM IO bus list with API kvm_io_bus_register_dev(). In MMIO/IOCSR
register access emulation, kvm_io_bus_read()/kvm_io_bus_write() is
called firstly. If it returns 0, it means that the in-kernel irqchip
handles the emulation already, else it returns to user-mode VMM and
lets VMM emulate the register access.

Once in-kernel irqchip is enabled, it should return 0 if the address
is within range of the registered KVM IO bus. It should not return to
user-mode VMM since VMM does not know how to handle it, and irqchip is
handled in kernel already.

Here set default return value with 0 in KVM IO bus operations.

Signed-off-by: Bibo Mao <maobibo@loongson.cn>
Signed-off-by: Huacai Chen <chenhuacai@loongson.cn>
2026-02-06 09:28:00 +08:00
Bibo Mao
382c38c9ec LoongArch: KVM: Add FPU/LBT delay load support
FPU/LBT are lazy enabled with KVM hypervisor. After FPU/LBT enabled and
loaded, vCPU can be preempted and FPU/LBT will be lost again, there will
be unnecessary FPU/LBT exceptions, load and store stuff. Here delay the
FPU/LBT load until the guest entry.

Signed-off-by: Bibo Mao <maobibo@loongson.cn>
Signed-off-by: Huacai Chen <chenhuacai@loongson.cn>
2026-02-06 09:28:00 +08:00
Bibo Mao
b1388a9598 LoongArch: KVM: Move LBT capability check in exception handler
Like FPU exception handler, check LBT capability in the LBT exception
handler rather than function kvm_own_lbt().

Signed-off-by: Bibo Mao <maobibo@loongson.cn>
Signed-off-by: Huacai Chen <chenhuacai@loongson.cn>
2026-02-06 09:27:47 +08:00
Bibo Mao
37da26e0e8 LoongArch: KVM: Move LASX capability check in exception handler
Like FPU exception handler, check LASX capability in the LASX exception
handler rather than function kvm_own_lasx(). Since LASX capability in
the function kvm_guest_has_lasx() implies FPU and LSX capability, only
checking kvm_guest_has_lasx() is OK here.

Signed-off-by: Bibo Mao <maobibo@loongson.cn>
Signed-off-by: Huacai Chen <chenhuacai@loongson.cn>
2026-02-06 09:27:47 +08:00
Bibo Mao
89b5dc5397 LoongArch: KVM: Move LSX capability check in exception handler
Like FPU exception handler, check LSX capability in the LSX exception
handler rather than function kvm_own_lsx(). Since LSX capability in
the function kvm_guest_has_lsx() implies FPU capability, only checking
kvm_guest_has_lsx() is OK here.

Signed-off-by: Bibo Mao <maobibo@loongson.cn>
Signed-off-by: Huacai Chen <chenhuacai@loongson.cn>
2026-02-06 09:27:47 +08:00
Bibo Mao
c5cb12b81a LoongArch: KVM: Handle LOONGARCH_CSR_IPR during vCPU context switch
Register LOONGARCH_CSR_IPR is interrupt priority setting for nested
interrupt handling. Though LoongArch Linux AVEC driver does not use
this register, KVM hypervisor needs to save and restore this it during
vCPU context switch. Because Linux AVEC driver may use this register
in future, or other OS may use it.

Signed-off-by: Bibo Mao <maobibo@loongson.cn>
Signed-off-by: Huacai Chen <chenhuacai@loongson.cn>
2026-02-06 09:27:46 +08:00
Bibo Mao
c2f94dafe1 LoongArch: KVM: Check VM msgint feature during interrupt handling
During message interrupt handling and relative CSR registers saving and
restore, it is better to check VM msgint feature rather than host msgint
feature, because VM may disable this feature even if host supports this.

Signed-off-by: Bibo Mao <maobibo@loongson.cn>
Signed-off-by: Huacai Chen <chenhuacai@loongson.cn>
2026-02-06 09:27:46 +08:00
Bibo Mao
31966edb9a LoongArch: KVM: Add msgint registers in kvm_init_gcsr_flag()
Add flag HW_GCSR with msgint registers in function kvm_init_gcsr_flag().

Signed-off-by: Bibo Mao <maobibo@loongson.cn>
Signed-off-by: Huacai Chen <chenhuacai@loongson.cn>
2026-02-06 09:27:46 +08:00
Bibo Mao
82db90bf46 LoongArch: KVM: Move feature detection in kvm_vm_init_features()
VM feature detection is sparsed in function kvm_vm_init_features() and
kvm_vm_feature_has_attr(). Here move all the features detection in
function kvm_vm_init_features(), and there is only feature checking in
function kvm_vm_feature_has_attr().

Signed-off-by: Bibo Mao <maobibo@loongson.cn>
Signed-off-by: Huacai Chen <chenhuacai@loongson.cn>
2026-02-06 09:27:46 +08:00
Bibo Mao
de0c51370b LoongArch: KVM: Add more CPUCFG mask bits
With new CPU cores there are more features supported which are indicated
in CPUCFG2 bits 24:30 and CPUCFG3 bits 17:23. The KVM hypervisor cannot
enable or disable (most of) these features and there is no KVM exception
when instructions of these features are executed in guest mode.

Here add more CPUCFG mask support with LA664 CPU type.

Signed-off-by: Bibo Mao <maobibo@loongson.cn>
Signed-off-by: Huacai Chen <chenhuacai@loongson.cn>
2026-02-06 09:27:46 +08:00
Qiang Ma
1cf342a7c3 LoongArch: KVM: Fix kvm_device leak in kvm_pch_pic_destroy()
In kvm_ioctl_create_device(), kvm_device has allocated memory,
kvm_device->destroy() seems to be supposed to free its kvm_device
struct, but kvm_pch_pic_destroy() is not currently doing this, that
would lead to a memory leak.

So, fix it.

Cc: stable@vger.kernel.org
Reviewed-by: Bibo Mao <maobibo@loongson.cn>
Signed-off-by: Qiang Ma <maqianga@uniontech.com>
Signed-off-by: Huacai Chen <chenhuacai@loongson.cn>
2026-01-17 10:57:03 +08:00
Qiang Ma
7d8553fc75 LoongArch: KVM: Fix kvm_device leak in kvm_eiointc_destroy()
In kvm_ioctl_create_device(), kvm_device has allocated memory,
kvm_device->destroy() seems to be supposed to free its kvm_device
struct, but kvm_eiointc_destroy() is not currently doing this, that
would lead to a memory leak.

So, fix it.

Cc: stable@vger.kernel.org
Reviewed-by: Bibo Mao <maobibo@loongson.cn>
Signed-off-by: Qiang Ma <maqianga@uniontech.com>
Signed-off-by: Huacai Chen <chenhuacai@loongson.cn>
2026-01-17 10:57:02 +08:00
Qiang Ma
0bf58cb728 LoongArch: KVM: Fix kvm_device leak in kvm_ipi_destroy()
In kvm_ioctl_create_device(), kvm_device has allocated memory,
kvm_device->destroy() seems to be supposed to free its kvm_device
struct, but kvm_ipi_destroy() is not currently doing this, that
would lead to a memory leak.

So, fix it.

Cc: stable@vger.kernel.org
Reviewed-by: Bibo Mao <maobibo@loongson.cn>
Signed-off-by: Qiang Ma <maqianga@uniontech.com>
Signed-off-by: Huacai Chen <chenhuacai@loongson.cn>
2026-01-17 10:57:02 +08:00
Sean Christopherson
4b24910c05 KVM: Add a simplified wrapper for registering perf callbacks
Add a parameter-less API for registering perf callbacks in anticipation of
introducing another x86-only parameter for handling mediated PMU PMIs.

No functional change intended.

Acked-by: Anup Patel <anup@brainfault.org>
Tested-by: Xudong Hao <xudong.hao@intel.com>
Tested-by: Manali Shukla <manali.shukla@amd.com>
Link: https://patch.msgid.link/20251206001720.468579-15-seanjc@google.com
Signed-off-by: Sean Christopherson <seanjc@google.com>
2026-01-08 11:51:39 -08:00
Sean Christopherson
da142f3d37 KVM: Remove subtle "struct kvm_stats_desc" pseudo-overlay
Remove KVM's internal pseudo-overlay of kvm_stats_desc, which subtly
aliases the flexible name[] in the uAPI definition with a fixed-size array
of the same name.  The unusual embedded structure results in compiler
warnings due to -Wflex-array-member-not-at-end, and also necessitates an
extra level of dereferencing in KVM.  To avoid the "overlay", define the
uAPI structure to have a fixed-size name when building for the kernel.

Opportunistically clean up the indentation for the stats macros, and
replace spaces with tabs.

No functional change intended.

Reported-by: Gustavo A. R. Silva <gustavoars@kernel.org>
Closes: https://lore.kernel.org/all/aPfNKRpLfhmhYqfP@kspp
Acked-by: Marc Zyngier <maz@kernel.org>
Acked-by: Christian Borntraeger <borntraeger@linux.ibm.com>
[..]
Acked-by: Anup Patel <anup@brainfault.org>
Reviewed-by: Bibo Mao <maobibo@loongson.cn>
Acked-by: Gustavo A. R. Silva <gustavoars@kernel.org>
Link: https://patch.msgid.link/20251205232655.445294-1-seanjc@google.com
Signed-off-by: Sean Christopherson <seanjc@google.com>
2026-01-08 10:40:48 -08:00
Linus Torvalds
9551a26f17 LoongArch changes for v6.19
1, Add basic LoongArch32 support;
 2, Select HAVE_ARCH_BITREVERSE in Kconfig;
 3, Fix build and boot for CONFIG_RANDSTRUCT;
 4, Correct the calculation logic of thread_count;
 5, Some bug fixes and other small changes.
 
 Note: Build infrastructures of LoongArch32 are not enabled yet, because
 we need to adjust irqchip drivers and wait for GNU toolchain be upstream
 first.
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Merge tag 'loongarch-6.19' of git://git.kernel.org/pub/scm/linux/kernel/git/chenhuacai/linux-loongson

Pull LoongArch updates from Huacai Chen:

 - Add basic LoongArch32 support

   Note: Build infrastructures of LoongArch32 are not enabled yet,
   because we need to adjust irqchip drivers and wait for GNU toolchain
   be upstream first.

 - Select HAVE_ARCH_BITREVERSE in Kconfig

 - Fix build and boot for CONFIG_RANDSTRUCT

 - Correct the calculation logic of thread_count

 - Some bug fixes and other small changes

* tag 'loongarch-6.19' of git://git.kernel.org/pub/scm/linux/kernel/git/chenhuacai/linux-loongson: (22 commits)
  LoongArch: Adjust default config files for 32BIT/64BIT
  LoongArch: Adjust VDSO/VSYSCALL for 32BIT/64BIT
  LoongArch: Adjust misc routines for 32BIT/64BIT
  LoongArch: Adjust user accessors for 32BIT/64BIT
  LoongArch: Adjust system call for 32BIT/64BIT
  LoongArch: Adjust module loader for 32BIT/64BIT
  LoongArch: Adjust time routines for 32BIT/64BIT
  LoongArch: Adjust process management for 32BIT/64BIT
  LoongArch: Adjust memory management for 32BIT/64BIT
  LoongArch: Adjust boot & setup for 32BIT/64BIT
  LoongArch: Adjust common macro definitions for 32BIT/64BIT
  LoongArch: Add adaptive CSR accessors for 32BIT/64BIT
  LoongArch: Add atomic operations for 32BIT/64BIT
  LoongArch: Add new PCI ID for pci_fixup_vgadev()
  LoongArch: Add and use some macros for AVEC
  LoongArch: Correct the calculation logic of thread_count
  LoongArch: Use unsigned long for _end and _text
  LoongArch: Use __pmd()/__pte() for swap entry conversions
  LoongArch: Fix arch_dup_task_struct() for CONFIG_RANDSTRUCT
  LoongArch: Fix build errors for CONFIG_RANDSTRUCT
  ...
2025-12-13 05:44:03 +12:00
Huacai Chen
ced7814d3a LoongArch: Adjust time routines for 32BIT/64BIT
Adjust time routines for both 32BIT and 64BIT, including: rdtime_h() /
rdtime_l() definitions for 32BIT and rdtime_d() definition for 64BIT,
get_cycles() and get_cycles64() definitions for 32BIT/64BIT, show time
frequency info ("CPU MHz" and "BogoMIPS") in /proc/cpuinfo, etc.

Use do_div() for division which works on both 32BIT and 64BIT platforms.

Reviewed-by: Arnd Bergmann <arnd@arndb.de>
Signed-off-by: Jiaxun Yang <jiaxun.yang@flygoat.com>
Signed-off-by: Huacai Chen <chenhuacai@loongson.cn>
2025-12-08 18:09:17 +08:00
Paolo Bonzini
8040280405 LoongArch KVM changes for v6.19
1. Get VM PMU capability from HW GCFG register.
 2. Add AVEC basic support.
 3. Use 64-bit register definition for EIOINTC.
 4. Add KVM timer test cases for tools/selftests.
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Merge tag 'loongarch-kvm-6.19' of git://git.kernel.org/pub/scm/linux/kernel/git/chenhuacai/linux-loongson into HEAD

LoongArch KVM changes for v6.19

1. Get VM PMU capability from HW GCFG register.
2. Add AVEC basic support.
3. Use 64-bit register definition for EIOINTC.
4. Add KVM timer test cases for tools/selftests.
2025-12-02 18:34:22 +01:00
Bibo Mao
d3e43a1f34 LoongArch: KVM: Use 64-bit register definition for EIOINTC
With in-kernel emulated eiointc driver, hardware register can be
accessed by different size, there is reg_u8/reg_u16/reg_u32/reg_u64
union type with EIOINTC register.

Here use 64-bit type with register definition and remove union type
since most registers are accessed with 64-bit method. And this makes
EIOINTC emulated driver simpler.

Signed-off-by: Bibo Mao <maobibo@loongson.cn>
Signed-off-by: Huacai Chen <chenhuacai@loongson.cn>
2025-11-27 11:00:18 +08:00
Song Gao
7bcd8d0b22 LoongArch: KVM: Add AVEC basic support
Check whether the host CPU supported AVEC, and save/restore CSR_MSGIS0-
CSR_MSGIS3 when necessary.

Reviewed-by: Bibo Mao <maobibo@loongson.cn>
Signed-off-by: Song Gao <gaosong@loongson.cn>
Signed-off-by: Huacai Chen <chenhuacai@loongson.cn>
2025-11-27 11:00:18 +08:00