[GIT PULL] KVM/arm64 fixes for 6.3, part #2

* [GIT PULL] KVM/arm64 fixes for 6.3, part #2
@ 2023-03-17  3:09 Oliver Upton
  2023-03-24 18:16 ` Oliver Upton
  0 siblings, 1 reply; 6+ messages in thread
From: Oliver Upton @ 2023-03-17  3:09 UTC (permalink / raw)
  To: Paolo Bonzini
  Cc: maz, reijiw, dmatlack, james.morse, suzuki.poulose, yuzenghui,
	kvmarm, kvm

Hi Paolo,

Another week, another set of fixes for KVM/arm64.

Description can be found in the tag, but the teardown race when walking
host page tables is particularly nasty and currently causing problems
for folks. The fix is quite simple by disabling interrupts when walking
host page tables, as the thread must be IPI'ed before the table memory
can actually be freed.

Please pull,

Oliver

The following changes since commit 47053904e18282af4525a02e3e0f519f014fc7f9:

  KVM: arm64: timers: Convert per-vcpu virtual offset to a global value (2023-03-11 02:00:40 -0800)

are available in the Git repository at:

  git://git.kernel.org/pub/scm/linux/kernel/git/kvmarm/kvmarm.git tags/kvmarm-fixes-6.3-2

for you to fetch changes up to 8c2e8ac8ad4be68409e806ce1cc78fc7a04539f3:

  KVM: arm64: Check for kvm_vma_mte_allowed in the critical section (2023-03-16 23:42:56 +0000)

----------------------------------------------------------------
KVM/arm64 fixes for 6.3, part #2

Fixes for a rather interesting set of bugs relating to the MMU:

 - Read the MMU notifier seq before dropping the mmap lock to guard
   against reading a potentially stale VMA

 - Disable interrupts when walking user page tables to protect against
   the page table being freed

 - Read the MTE permissions for the VMA within the mmap lock critical
   section, avoiding the use of a potentally stale VMA pointer

Additionally, some fixes targeting the vPMU:

 - Return the sum of the current perf event value and PMC snapshot for
   reads from userspace

 - Don't save the value of guest writes to PMCR_EL0.{C,P}, which could
   otherwise lead to userspace erroneously resetting the vPMU during VM
   save/restore

----------------------------------------------------------------
David Matlack (1):
      KVM: arm64: Retry fault if vma_lookup() results become invalid

Marc Zyngier (2):
      KVM: arm64: Disable interrupts while walking userspace PTs
      KVM: arm64: Check for kvm_vma_mte_allowed in the critical section

Reiji Watanabe (2):
      KVM: arm64: PMU: Fix GET_ONE_REG for vPMC regs to return the current value
      KVM: arm64: PMU: Don't save PMCR_EL0.{C,P} for the vCPU

 arch/arm64/kvm/mmu.c      | 99 ++++++++++++++++++++++++++++++-----------------
 arch/arm64/kvm/pmu-emul.c |  3 +-
 arch/arm64/kvm/sys_regs.c | 21 +++++++++-
 3 files changed, 85 insertions(+), 38 deletions(-)

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