Re: [GIT PULL] KVM/arm64 updates for 6.2

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On 12/5/22 16:58, Marc Zyngier wrote:
- There is a lot of selftest conflicts with your own branch, see:

   https://lore.kernel.org/r/20221201112432.4cb9ae42@xxxxxxxxxxxxxxxx
   https://lore.kernel.org/r/20221201113626.438f13c5@xxxxxxxxxxxxxxxx
   https://lore.kernel.org/r/20221201115741.7de32422@xxxxxxxxxxxxxxxx
   https://lore.kernel.org/r/20221201120939.3c19f004@xxxxxxxxxxxxxxxx
   https://lore.kernel.org/r/20221201131623.18ebc8d8@xxxxxxxxxxxxxxxx

   for a rather exhaustive collection.

Yeah, I saw them in Stephen's messages but missed your reply.

In retrospect, at least Gavin's series for memslot_perf_test should have
been applied by both of us with a topic branch, but there's so many
conflicts all over the place that it's hard to single out one series.
It just happens.

The only conflict in non-x86 code is the following one, please check
if I got it right.

diff --git a/tools/testing/selftests/kvm/aarch64/page_fault_test.c b/tools/testing/selftests/kvm/aarch64/page_fault_test.c
index 05bb6a6369c2..0cda70bef5d5 100644
--- a/tools/testing/selftests/kvm/aarch64/page_fault_test.c
+++ b/tools/testing/selftests/kvm/aarch64/page_fault_test.c
@@ -609,6 +609,8 @@ static void setup_memslots(struct kvm_vm *vm, struct test_params *p)
 				    data_size / guest_page_size,
 				    p->test_desc->data_memslot_flags);
 	vm->memslots[MEM_REGION_TEST_DATA] = TEST_DATA_MEMSLOT;
+
+	ucall_init(vm, data_gpa + data_size);
 }
static void setup_default_handlers(struct test_desc *test)
@@ -704,8 +706,6 @@ static void run_test(enum vm_guest_mode mode, void *arg)
setup_gva_maps(vm); - ucall_init(vm, NULL);
-
 	reset_event_counts();
/*


Special care is needed here because the test uses ____vm_create().

I haven't pushed to kvm/next yet to give you time to check, so the
merge is currently in kvm/queue only.

- For the 6.3 cycle, we are going to experiment with Oliver taking
   care of most of the patch herding. I'm sure he'll do a great job,
   but if there is the odd mistake, please cut him some slack and blame
   me instead.

Absolutely - you both have all the slack you need, synchronization
is harder than it seems.

Paolo

Please pull,

	M.

The following changes since commit f0c4d9fc9cc9462659728d168387191387e903cc:

   Linux 6.1-rc4 (2022-11-06 15:07:11 -0800)

are available in the Git repository at:

   git://git.kernel.org/pub/scm/linux/kernel/git/kvmarm/kvmarm.git tags/kvmarm-6.2

for you to fetch changes up to 753d734f3f347e7fc49b819472bbf61dcfc1a16f:

   Merge remote-tracking branch 'arm64/for-next/sysregs' into kvmarm-master/next (2022-12-05 14:39:53 +0000)

----------------------------------------------------------------
KVM/arm64 updates for 6.2

- Enable the per-vcpu dirty-ring tracking mechanism, together with an
   option to keep the good old dirty log around for pages that are
   dirtied by something other than a vcpu.

- Switch to the relaxed parallel fault handling, using RCU to delay
   page table reclaim and giving better performance under load.

- Relax the MTE ABI, allowing a VMM to use the MAP_SHARED mapping
   option, which multi-process VMMs such as crosvm rely on.

- Merge the pKVM shadow vcpu state tracking that allows the hypervisor
   to have its own view of a vcpu, keeping that state private.

- Add support for the PMUv3p5 architecture revision, bringing support
   for 64bit counters on systems that support it, and fix the
   no-quite-compliant CHAIN-ed counter support for the machines that
   actually exist out there.

- Fix a handful of minor issues around 52bit VA/PA support (64kB pages
   only) as a prefix of the oncoming support for 4kB and 16kB pages.

- Add/Enable/Fix a bunch of selftests covering memslots, breakpoints,
   stage-2 faults and access tracking. You name it, we got it, we
   probably broke it.

- Pick a small set of documentation and spelling fixes, because no
   good merge window would be complete without those.

As a side effect, this tag also drags:

- The 'kvmarm-fixes-6.1-3' tag as a dependency to the dirty-ring
   series

- A shared branch with the arm64 tree that repaints all the system
   registers to match the ARM ARM's naming, and resulting in
   interesting conflicts

----------------------------------------------------------------
Anshuman Khandual (1):
       KVM: arm64: PMU: Replace version number '0' with ID_AA64DFR0_EL1_PMUVer_NI

Catalin Marinas (4):
       mm: Do not enable PG_arch_2 for all 64-bit architectures
       arm64: mte: Fix/clarify the PG_mte_tagged semantics
       KVM: arm64: Simplify the sanitise_mte_tags() logic
       arm64: mte: Lock a page for MTE tag initialisation

Fuad Tabba (3):
       KVM: arm64: Add hyp_spinlock_t static initializer
       KVM: arm64: Add infrastructure to create and track pKVM instances at EL2
       KVM: arm64: Instantiate pKVM hypervisor VM and vCPU structures from EL1

Gavin Shan (14):
       KVM: x86: Introduce KVM_REQ_DIRTY_RING_SOFT_FULL
       KVM: Move declaration of kvm_cpu_dirty_log_size() to kvm_dirty_ring.h
       KVM: Support dirty ring in conjunction with bitmap
       KVM: arm64: Enable ring-based dirty memory tracking
       KVM: selftests: Use host page size to map ring buffer in dirty_log_test
       KVM: selftests: Clear dirty ring states between two modes in dirty_log_test
       KVM: selftests: Automate choosing dirty ring size in dirty_log_test
       KVM: selftests: memslot_perf_test: Use data->nslots in prepare_vm()
       KVM: selftests: memslot_perf_test: Consolidate loop conditions in prepare_vm()
       KVM: selftests: memslot_perf_test: Probe memory slots for once
       KVM: selftests: memslot_perf_test: Support variable guest page size
       KVM: selftests: memslot_perf_test: Consolidate memory
       KVM: selftests: memslot_perf_test: Report optimal memory slots
       KVM: Push dirty information unconditionally to backup bitmap

James Morse (38):
       arm64/sysreg: Standardise naming for ID_MMFR0_EL1
       arm64/sysreg: Standardise naming for ID_MMFR4_EL1
       arm64/sysreg: Standardise naming for ID_MMFR5_EL1
       arm64/sysreg: Standardise naming for ID_ISAR0_EL1
       arm64/sysreg: Standardise naming for ID_ISAR4_EL1
       arm64/sysreg: Standardise naming for ID_ISAR5_EL1
       arm64/sysreg: Standardise naming for ID_ISAR6_EL1
       arm64/sysreg: Standardise naming for ID_PFR0_EL1
       arm64/sysreg: Standardise naming for ID_PFR1_EL1
       arm64/sysreg: Standardise naming for ID_PFR2_EL1
       arm64/sysreg: Standardise naming for ID_DFR0_EL1
       arm64/sysreg: Standardise naming for ID_DFR1_EL1
       arm64/sysreg: Standardise naming for MVFR0_EL1
       arm64/sysreg: Standardise naming for MVFR1_EL1
       arm64/sysreg: Standardise naming for MVFR2_EL1
       arm64/sysreg: Extend the maximum width of a register and symbol name
       arm64/sysreg: Convert ID_MMFR0_EL1 to automatic generation
       arm64/sysreg: Convert ID_MMFR1_EL1 to automatic generation
       arm64/sysreg: Convert ID_MMFR2_EL1 to automatic generation
       arm64/sysreg: Convert ID_MMFR3_EL1 to automatic generation
       arm64/sysreg: Convert ID_MMFR4_EL1 to automatic generation
       arm64/sysreg: Convert ID_ISAR0_EL1 to automatic generation
       arm64/sysreg: Convert ID_ISAR1_EL1 to automatic generation
       arm64/sysreg: Convert ID_ISAR2_EL1 to automatic generation
       arm64/sysreg: Convert ID_ISAR3_EL1 to automatic generation
       arm64/sysreg: Convert ID_ISAR4_EL1 to automatic generation
       arm64/sysreg: Convert ID_ISAR5_EL1 to automatic generation
       arm64/sysreg: Convert ID_ISAR6_EL1 to automatic generation
       arm64/sysreg: Convert ID_PFR0_EL1 to automatic generation
       arm64/sysreg: Convert ID_PFR1_EL1 to automatic generation
       arm64/sysreg: Convert ID_PFR2_EL1 to automatic generation
       arm64/sysreg: Convert MVFR0_EL1 to automatic generation
       arm64/sysreg: Convert MVFR1_EL1 to automatic generation
       arm64/sysreg: Convert MVFR2_EL1 to automatic generation
       arm64/sysreg: Convert ID_MMFR5_EL1 to automatic generation
       arm64/sysreg: Convert ID_AFR0_EL1 to automatic generation
       arm64/sysreg: Convert ID_DFR0_EL1 to automatic generation
       arm64/sysreg: Convert ID_DFR1_EL1 to automatic generation

Marc Zyngier (32):
       Merge tag 'kvmarm-fixes-6.1-3' into kvm-arm64/dirty-ring
       arm64: Add ID_DFR0_EL1.PerfMon values for PMUv3p7 and IMP_DEF
       KVM: arm64: PMU: Align chained counter implementation with architecture pseudocode
       KVM: arm64: PMU: Always advertise the CHAIN event
       KVM: arm64: PMU: Distinguish between 64bit counter and 64bit overflow
       KVM: arm64: PMU: Narrow the overflow checking when required
       KVM: arm64: PMU: Only narrow counters that are not 64bit wide
       KVM: arm64: PMU: Add counter_index_to_*reg() helpers
       KVM: arm64: PMU: Simplify setting a counter to a specific value
       KVM: arm64: PMU: Do not let AArch32 change the counters' top 32 bits
       KVM: arm64: PMU: Move the ID_AA64DFR0_EL1.PMUver limit to VM creation
       KVM: arm64: PMU: Allow ID_AA64DFR0_EL1.PMUver to be set from userspace
       KVM: arm64: PMU: Allow ID_DFR0_EL1.PerfMon to be set from userspace
       KVM: arm64: PMU: Implement PMUv3p5 long counter support
       KVM: arm64: PMU: Allow PMUv3p5 to be exposed to the guest
       KVM: arm64: PMU: Simplify vcpu computation on perf overflow notification
       KVM: arm64: PMU: Make kvm_pmc the main data structure
       KVM: arm64: PMU: Simplify PMCR_EL0 reset handling
       KVM: arm64: PMU: Sanitise PMCR_EL0.LP on first vcpu run
       KVM: arm64: PMU: Fix period computation for 64bit counters with 32bit overflow
       Merge branch kvm-arm64/selftest/memslot-fixes into kvmarm-master/next
       Merge branch kvm-arm64/selftest/linked-bps into kvmarm-master/next
       Merge branch kvm-arm64/selftest/s2-faults into kvmarm-master/next
       Merge branch kvm-arm64/selftest/access-tracking into kvmarm-master/next
       Merge branch kvm-arm64/52bit-fixes into kvmarm-master/next
       Merge branch kvm-arm64/dirty-ring into kvmarm-master/next
       Merge branch kvm-arm64/parallel-faults into kvmarm-master/next
       Merge branch kvm-arm64/pkvm-vcpu-state into kvmarm-master/next
       Merge branch kvm-arm64/mte-map-shared into kvmarm-master/next
       Merge branch kvm-arm64/pmu-unchained into kvmarm-master/next
       Merge branch kvm-arm64/misc-6.2 into kvmarm-master/next
       Merge remote-tracking branch 'arm64/for-next/sysregs' into kvmarm-master/next

Oliver Upton (19):
       KVM: arm64: Combine visitor arguments into a context structure
       KVM: arm64: Stash observed pte value in visitor context
       KVM: arm64: Pass mm_ops through the visitor context
       KVM: arm64: Don't pass kvm_pgtable through kvm_pgtable_walk_data
       KVM: arm64: Add a helper to tear down unlinked stage-2 subtrees
       KVM: arm64: Use an opaque type for pteps
       KVM: arm64: Tear down unlinked stage-2 subtree after break-before-make
       KVM: arm64: Protect stage-2 traversal with RCU
       KVM: arm64: Atomically update stage 2 leaf attributes in parallel walks
       KVM: arm64: Split init and set for table PTE
       KVM: arm64: Make block->table PTE changes parallel-aware
       KVM: arm64: Make leaf->leaf PTE changes parallel-aware
       KVM: arm64: Make table->block changes parallel-aware
       KVM: arm64: Handle stage-2 faults in parallel
       KVM: arm64: Take a pointer to walker data in kvm_dereference_pteref()
       KVM: arm64: Don't acquire RCU read lock for exclusive table walks
       KVM: arm64: Reject shared table walks in the hyp code
       KVM: selftests: Have perf_test_util signal when to stop vCPUs
       KVM: selftests: Build access_tracking_perf_test for arm64

Peter Collingbourne (4):
       mm: Add PG_arch_3 page flag
       KVM: arm64: unify the tests for VMAs in memslots when MTE is enabled
       KVM: arm64: permit all VM_MTE_ALLOWED mappings with MTE enabled
       Documentation: document the ABI changes for KVM_CAP_ARM_MTE

Quentin Perret (14):
       KVM: arm64: Move hyp refcount manipulation helpers to common header file
       KVM: arm64: Allow attaching of non-coalescable pages to a hyp pool
       KVM: arm64: Back the hypervisor 'struct hyp_page' array for all memory
       KVM: arm64: Fix-up hyp stage-1 refcounts for all pages mapped at EL2
       KVM: arm64: Prevent the donation of no-map pages
       KVM: arm64: Add helpers to pin memory shared with the hypervisor at EL2
       KVM: arm64: Add per-cpu fixmap infrastructure at EL2
       KVM: arm64: Add generic hyp_memcache helpers
       KVM: arm64: Consolidate stage-2 initialisation into a single function
       KVM: arm64: Instantiate guest stage-2 page-tables at EL2
       KVM: arm64: Return guest memory from EL2 via dedicated teardown memcache
       KVM: arm64: Unmap 'kvm_arm_hyp_percpu_base' from the host
       KVM: arm64: Explicitly map 'kvm_vgic_global_state' at EL2
       KVM: arm64: Don't unnecessarily map host kernel sections at EL2

Reiji Watanabe (9):
       KVM: arm64: selftests: Use FIELD_GET() to extract ID register fields
       KVM: arm64: selftests: Add write_dbg{b,w}{c,v}r helpers in debug-exceptions
       KVM: arm64: selftests: Remove the hard-coded {b,w}pn#0 from debug-exceptions
       KVM: arm64: selftests: Add helpers to enable debug exceptions
       KVM: arm64: selftests: Stop unnecessary test stage tracking of debug-exceptions
       KVM: arm64: selftests: Change debug_version() to take ID_AA64DFR0_EL1
       KVM: arm64: selftests: Add a test case for a linked breakpoint
       KVM: arm64: selftests: Add a test case for a linked watchpoint
       KVM: arm64: selftests: Test with every breakpoint/watchpoint

Ricardo Koller (14):
       KVM: selftests: Add a userfaultfd library
       KVM: selftests: aarch64: Add virt_get_pte_hva() library function
       KVM: selftests: Add missing close and munmap in __vm_mem_region_delete()
       KVM: selftests: aarch64: Construct DEFAULT_MAIR_EL1 using sysreg.h macros
       tools: Copy bitfield.h from the kernel sources
       KVM: selftests: Stash backing_src_type in struct userspace_mem_region
       KVM: selftests: Add vm->memslots[] and enum kvm_mem_region_type
       KVM: selftests: Fix alignment in virt_arch_pgd_alloc() and vm_vaddr_alloc()
       KVM: selftests: Use the right memslot for code, page-tables, and data allocations
       KVM: selftests: aarch64: Add aarch64/page_fault_test
       KVM: selftests: aarch64: Add userfaultfd tests into page_fault_test
       KVM: selftests: aarch64: Add dirty logging tests into page_fault_test
       KVM: selftests: aarch64: Add readonly memslot tests into page_fault_test
       KVM: selftests: aarch64: Add mix of tests into page_fault_test

Ryan Roberts (3):
       KVM: arm64: Fix kvm init failure when mode!=vhe and VA_BITS=52.
       KVM: arm64: Fix PAR_TO_HPFAR() to work independently of PA_BITS.
       KVM: arm64: Fix benign bug with incorrect use of VA_BITS

Usama Arif (1):
       KVM: arm64: Fix pvtime documentation

Will Deacon (9):
       KVM: arm64: Unify identifiers used to distinguish host and hypervisor
       KVM: arm64: Implement do_donate() helper for donating memory
       KVM: arm64: Include asm/kvm_mmu.h in nvhe/mem_protect.h
       KVM: arm64: Rename 'host_kvm' to 'host_mmu'
       KVM: arm64: Initialise hypervisor copies of host symbols unconditionally
       KVM: arm64: Provide I-cache invalidation by virtual address at EL2
       KVM: arm64: Maintain a copy of 'kvm_arm_vmid_bits' at EL2
       KVM: arm64: Use the pKVM hyp vCPU structure in handle___kvm_vcpu_run()
       arm64/sysreg: Remove duplicate definitions from asm/sysreg.h

Zhiyuan Dai (1):
       KVM: arm64: Fix typo in comment

  Documentation/virt/kvm/api.rst                     |   41 +-
  Documentation/virt/kvm/arm/pvtime.rst              |   14 +-
  Documentation/virt/kvm/devices/arm-vgic-its.rst    |    5 +-
  Documentation/virt/kvm/devices/vcpu.rst            |    2 +
  arch/arm64/Kconfig                                 |    1 +
  arch/arm64/include/asm/kvm_arm.h                   |    8 +-
  arch/arm64/include/asm/kvm_asm.h                   |    7 +-
  arch/arm64/include/asm/kvm_host.h                  |   76 +-
  arch/arm64/include/asm/kvm_hyp.h                   |    3 +
  arch/arm64/include/asm/kvm_mmu.h                   |    2 +-
  arch/arm64/include/asm/kvm_pgtable.h               |  175 ++-
  arch/arm64/include/asm/kvm_pkvm.h                  |   38 +
  arch/arm64/include/asm/mte.h                       |   65 +-
  arch/arm64/include/asm/pgtable.h                   |    4 +-
  arch/arm64/include/asm/sysreg.h                    |  138 ---
  arch/arm64/include/uapi/asm/kvm.h                  |    1 +
  arch/arm64/kernel/cpufeature.c                     |  212 ++--
  arch/arm64/kernel/elfcore.c                        |    2 +-
  arch/arm64/kernel/hibernate.c                      |    2 +-
  arch/arm64/kernel/image-vars.h                     |   15 -
  arch/arm64/kernel/mte.c                            |   21 +-
  arch/arm64/kvm/Kconfig                             |    2 +
  arch/arm64/kvm/arm.c                               |   90 +-
  arch/arm64/kvm/guest.c                             |   18 +-
  arch/arm64/kvm/hyp/hyp-constants.c                 |    3 +
  arch/arm64/kvm/hyp/include/nvhe/mem_protect.h      |   25 +-
  arch/arm64/kvm/hyp/include/nvhe/memory.h           |   27 +
  arch/arm64/kvm/hyp/include/nvhe/mm.h               |   18 +-
  arch/arm64/kvm/hyp/include/nvhe/pkvm.h             |   68 ++
  arch/arm64/kvm/hyp/include/nvhe/spinlock.h         |   10 +-
  arch/arm64/kvm/hyp/nvhe/cache.S                    |   11 +
  arch/arm64/kvm/hyp/nvhe/hyp-main.c                 |  110 +-
  arch/arm64/kvm/hyp/nvhe/hyp-smp.c                  |    2 +
  arch/arm64/kvm/hyp/nvhe/mem_protect.c              |  521 ++++++++-
  arch/arm64/kvm/hyp/nvhe/mm.c                       |  167 ++-
  arch/arm64/kvm/hyp/nvhe/page_alloc.c               |   29 +-
  arch/arm64/kvm/hyp/nvhe/pkvm.c                     |  436 ++++++++
  arch/arm64/kvm/hyp/nvhe/setup.c                    |   98 +-
  arch/arm64/kvm/hyp/pgtable.c                       |  652 ++++++------
  arch/arm64/kvm/hyp/vhe/Makefile                    |    2 +-
  arch/arm64/kvm/mmu.c                               |  193 ++--
  arch/arm64/kvm/pkvm.c                              |  138 ++-
  arch/arm64/kvm/pmu-emul.c                          |  482 ++++-----
  arch/arm64/kvm/reset.c                             |   29 -
  arch/arm64/kvm/sys_regs.c                          |  157 ++-
  arch/arm64/kvm/vgic/vgic-its.c                     |   20 +
  arch/arm64/lib/mte.S                               |    2 +-
  arch/arm64/mm/copypage.c                           |    7 +-
  arch/arm64/mm/fault.c                              |    4 +-
  arch/arm64/mm/mteswap.c                            |   16 +-
  arch/arm64/tools/gen-sysreg.awk                    |    2 +-
  arch/arm64/tools/sysreg                            |  754 +++++++++++++
  arch/x86/include/asm/kvm_host.h                    |    2 -
  arch/x86/kvm/x86.c                                 |   15 +-
  fs/proc/page.c                                     |    3 +-
  include/kvm/arm_pmu.h                              |   15 +-
  include/kvm/arm_vgic.h                             |    1 +
  include/linux/kernel-page-flags.h                  |    1 +
  include/linux/kvm_dirty_ring.h                     |   20 +-
  include/linux/kvm_host.h                           |   10 +-
  include/linux/page-flags.h                         |    3 +-
  include/trace/events/mmflags.h                     |    9 +-
  include/uapi/linux/kvm.h                           |    1 +
  mm/Kconfig                                         |    8 +
  mm/huge_memory.c                                   |    3 +-
  tools/include/linux/bitfield.h                     |  176 ++++
  tools/testing/selftests/kvm/.gitignore             |    1 +
  tools/testing/selftests/kvm/Makefile               |    3 +
  .../selftests/kvm/aarch64/aarch32_id_regs.c        |    3 +-
  .../selftests/kvm/aarch64/debug-exceptions.c       |  311 ++++--
  .../selftests/kvm/aarch64/page_fault_test.c        | 1112 ++++++++++++++++++++
  .../selftests/kvm/access_tracking_perf_test.c      |    8 +-
  tools/testing/selftests/kvm/demand_paging_test.c   |  228 +---
  tools/testing/selftests/kvm/dirty_log_test.c       |   53 +-
  .../selftests/kvm/include/aarch64/processor.h      |   35 +-
  .../testing/selftests/kvm/include/kvm_util_base.h  |   31 +-
  .../testing/selftests/kvm/include/perf_test_util.h |    3 +
  .../selftests/kvm/include/userfaultfd_util.h       |   45 +
  .../testing/selftests/kvm/lib/aarch64/processor.c  |   55 +-
  tools/testing/selftests/kvm/lib/elf.c              |    3 +-
  tools/testing/selftests/kvm/lib/kvm_util.c         |   84 +-
  tools/testing/selftests/kvm/lib/perf_test_util.c   |    3 +
  tools/testing/selftests/kvm/lib/riscv/processor.c  |   29 +-
  tools/testing/selftests/kvm/lib/s390x/processor.c  |    8 +-
  tools/testing/selftests/kvm/lib/userfaultfd_util.c |  186 ++++
  tools/testing/selftests/kvm/lib/x86_64/processor.c |   13 +-
  .../kvm/memslot_modification_stress_test.c         |    6 +-
  tools/testing/selftests/kvm/memslot_perf_test.c    |  317 ++++--
  virt/kvm/Kconfig                                   |    6 +
  virt/kvm/dirty_ring.c                              |   46 +-
  virt/kvm/kvm_main.c                                |   65 +-
  91 files changed, 6073 insertions(+), 1773 deletions(-)
  create mode 100644 arch/arm64/kvm/hyp/include/nvhe/pkvm.h
  create mode 100644 tools/include/linux/bitfield.h
  create mode 100644 tools/testing/selftests/kvm/aarch64/page_fault_test.c
  create mode 100644 tools/testing/selftests/kvm/include/userfaultfd_util.h
  create mode 100644 tools/testing/selftests/kvm/lib/userfaultfd_util.c





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