1. 24 3月, 2020 1 次提交
  2. 29 10月, 2019 3 次提交
  3. 22 10月, 2019 1 次提交
  4. 25 8月, 2019 1 次提交
  5. 19 8月, 2019 1 次提交
  6. 05 8月, 2019 1 次提交
    • M
      KVM: arm/arm64: Sync ICH_VMCR_EL2 back when about to block · 5eeaf10e
      Marc Zyngier 提交于
      Since commit commit 328e5664 ("KVM: arm/arm64: vgic: Defer
      touching GICH_VMCR to vcpu_load/put"), we leave ICH_VMCR_EL2 (or
      its GICv2 equivalent) loaded as long as we can, only syncing it
      back when we're scheduled out.
      
      There is a small snag with that though: kvm_vgic_vcpu_pending_irq(),
      which is indirectly called from kvm_vcpu_check_block(), needs to
      evaluate the guest's view of ICC_PMR_EL1. At the point were we
      call kvm_vcpu_check_block(), the vcpu is still loaded, and whatever
      changes to PMR is not visible in memory until we do a vcpu_put().
      
      Things go really south if the guest does the following:
      
      	mov x0, #0	// or any small value masking interrupts
      	msr ICC_PMR_EL1, x0
      
      	[vcpu preempted, then rescheduled, VMCR sampled]
      
      	mov x0, #ff	// allow all interrupts
      	msr ICC_PMR_EL1, x0
      	wfi		// traps to EL2, so samping of VMCR
      
      	[interrupt arrives just after WFI]
      
      Here, the hypervisor's view of PMR is zero, while the guest has enabled
      its interrupts. kvm_vgic_vcpu_pending_irq() will then say that no
      interrupts are pending (despite an interrupt being received) and we'll
      block for no reason. If the guest doesn't have a periodic interrupt
      firing once it has blocked, it will stay there forever.
      
      To avoid this unfortuante situation, let's resync VMCR from
      kvm_arch_vcpu_blocking(), ensuring that a following kvm_vcpu_check_block()
      will observe the latest value of PMR.
      
      This has been found by booting an arm64 Linux guest with the pseudo NMI
      feature, and thus using interrupt priorities to mask interrupts instead
      of the usual PSTATE masking.
      
      Cc: stable@vger.kernel.org # 4.12
      Fixes: 328e5664 ("KVM: arm/arm64: vgic: Defer touching GICH_VMCR to vcpu_load/put")
      Signed-off-by: NMarc Zyngier <maz@kernel.org>
      5eeaf10e
  7. 23 7月, 2019 1 次提交
  8. 05 7月, 2019 3 次提交
  9. 19 6月, 2019 1 次提交
  10. 05 6月, 2019 2 次提交
  11. 20 2月, 2019 5 次提交
  12. 24 1月, 2019 3 次提交
  13. 20 12月, 2018 1 次提交
  14. 12 8月, 2018 1 次提交
  15. 21 7月, 2018 3 次提交
  16. 25 5月, 2018 3 次提交
  17. 27 4月, 2018 1 次提交
    • M
      KVM: arm/arm64: vgic: Fix source vcpu issues for GICv2 SGI · 53692908
      Marc Zyngier 提交于
      Now that we make sure we don't inject multiple instances of the
      same GICv2 SGI at the same time, we've made another bug more
      obvious:
      
      If we exit with an active SGI, we completely lose track of which
      vcpu it came from. On the next entry, we restore it with 0 as a
      source, and if that wasn't the right one, too bad. While this
      doesn't seem to trouble GIC-400, the architectural model gets
      offended and doesn't deactivate the interrupt on EOI.
      
      Another connected issue is that we will happilly make pending
      an interrupt from another vcpu, overriding the above zero with
      something that is just as inconsistent. Don't do that.
      
      The final issue is that we signal a maintenance interrupt when
      no pending interrupts are present in the LR. Assuming we've fixed
      the two issues above, we end-up in a situation where we keep
      exiting as soon as we've reached the active state, and not be
      able to inject the following pending.
      
      The fix comes in 3 parts:
      - GICv2 SGIs have their source vcpu saved if they are active on
        exit, and restored on entry
      - Multi-SGIs cannot go via the Pending+Active state, as this would
        corrupt the source field
      - Multi-SGIs are converted to using MI on EOI instead of NPIE
      
      Fixes: 16ca6a60 ("KVM: arm/arm64: vgic: Don't populate multiple LRs with the same vintid")
      Reported-by: NMark Rutland <mark.rutland@arm.com>
      Tested-by: NMark Rutland <mark.rutland@arm.com>
      Reviewed-by: NChristoffer Dall <christoffer.dall@arm.com>
      Signed-off-by: NMarc Zyngier <marc.zyngier@arm.com>
      53692908
  18. 20 4月, 2018 1 次提交
    • M
      arm/arm64: KVM: Add PSCI version selection API · 85bd0ba1
      Marc Zyngier 提交于
      Although we've implemented PSCI 0.1, 0.2 and 1.0, we expose either 0.1
      or 1.0 to a guest, defaulting to the latest version of the PSCI
      implementation that is compatible with the requested version. This is
      no different from doing a firmware upgrade on KVM.
      
      But in order to give a chance to hypothetical badly implemented guests
      that would have a fit by discovering something other than PSCI 0.2,
      let's provide a new API that allows userspace to pick one particular
      version of the API.
      
      This is implemented as a new class of "firmware" registers, where
      we expose the PSCI version. This allows the PSCI version to be
      save/restored as part of a guest migration, and also set to
      any supported version if the guest requires it.
      
      Cc: stable@vger.kernel.org #4.16
      Reviewed-by: NChristoffer Dall <cdall@kernel.org>
      Signed-off-by: NMarc Zyngier <marc.zyngier@arm.com>
      85bd0ba1
  19. 19 3月, 2018 2 次提交
  20. 15 3月, 2018 1 次提交
    • C
      KVM: arm/arm64: Reset mapped IRQs on VM reset · 413aa807
      Christoffer Dall 提交于
      We currently don't allow resetting mapped IRQs from userspace, because
      their state is controlled by the hardware.  But we do need to reset the
      state when the VM is reset, so we provide a function for the 'owner' of
      the mapped interrupt to reset the interrupt state.
      
      Currently only the timer uses mapped interrupts, so we call this
      function from the timer reset logic.
      
      Cc: stable@vger.kernel.org
      Fixes: 4c60e360 ("KVM: arm/arm64: Provide a get_input_level for the arch timer")
      Signed-off-by: NChristoffer Dall <cdall@kernel.org>
      Signed-off-by: NMarc Zyngier <marc.zyngier@arm.com>
      413aa807
  21. 07 2月, 2018 4 次提交