kernel/linux.git/include/kvm/arm_arch_timer.h, branch v6.12.80

Merge tag 'kvmarm-6.7' of git://git.kernel.org/pub/scm/linux/kernel/git/kvmarm/kvmarm into HEAD

2023-10-31T20:37:07+00:00

KVM/arm64 updates for 6.7 - Generalized infrastructure for 'writable' ID registers, effectively allowing userspace to opt-out of certain vCPU features for its guest - Optimization for vSGI injection, opportunistically compressing MPIDR to vCPU mapping into a table - Improvements to KVM's PMU emulation, allowing userspace to select the number of PMCs available to a VM - Guest support for memory operation instructions (FEAT_MOPS) - Cleanups to handling feature flags in KVM_ARM_VCPU_INIT, squashing bugs and getting rid of useless code - Changes to the way the SMCCC filter is constructed, avoiding wasted memory allocations when not in use - Load the stage-2 MMU context at vcpu_load() for VHE systems, reducing the overhead of errata mitigations - Miscellaneous kernel and selftest fixes

KVM: arm64: timers: Correctly handle TGE flip with CNTPOFF_EL2

2023-10-12T15:55:21+00:00

Contrary to common belief, HCR_EL2.TGE has a direct and immediate effect on the way the EL0 physical counter is offset. Flipping TGE from 1 to 0 while at EL2 immediately changes the way the counter compared to the CVAL limit. This means that we cannot directly save/restore the guest's view of CVAL, but that we instead must treat it as if CNTPOFF didn't exist. Only in the world switch, once we figure out that we do have CNTPOFF, can we must the offset back and forth depending on the polarity of TGE. Fixes: 2b4825a86940 ("KVM: arm64: timers: Use CNTPOFF_EL2 to offset the physical timer") Reported-by: Ganapatrao Kulkarni Tested-by: Ganapatrao Kulkarni Signed-off-by: Marc Zyngier

KVM: arm64: Remove unused return value from kvm_reset_vcpu()

2023-09-21T18:13:29+00:00

Get rid of the return value for kvm_reset_vcpu() as there are no longer any cases where it returns a nonzero value. Link: https://lore.kernel.org/r/20230920195036.1169791-8-oliver.upton@linux.dev Signed-off-by: Oliver Upton

Merge branch kvm-arm64/timer-vm-offsets into kvmarm-master/next

2023-04-21T08:36:40+00:00

* kvm-arm64/timer-vm-offsets: (21 commits) : . : This series aims at satisfying multiple goals: : : - allow a VMM to atomically restore a timer offset for a whole VM : instead of updating the offset each time a vcpu get its counter : written : : - allow a VMM to save/restore the physical timer context, something : that we cannot do at the moment due to the lack of offsetting : : - provide a framework that is suitable for NV support, where we get : both global and per timer, per vcpu offsetting, and manage : interrupts in a less braindead way. : : Conflict resolution involves using the new per-vcpu config lock instead : of the home-grown timer lock. : . KVM: arm64: Handle 32bit CNTPCTSS traps KVM: arm64: selftests: Augment existing timer test to handle variable offset KVM: arm64: selftests: Deal with spurious timer interrupts KVM: arm64: selftests: Add physical timer registers to the sysreg list KVM: arm64: nv: timers: Support hyp timer emulation KVM: arm64: nv: timers: Add a per-timer, per-vcpu offset KVM: arm64: Document KVM_ARM_SET_CNT_OFFSETS and co KVM: arm64: timers: Abstract the number of valid timers per vcpu KVM: arm64: timers: Fast-track CNTPCT_EL0 trap handling KVM: arm64: Elide kern_hyp_va() in VHE-specific parts of the hypervisor KVM: arm64: timers: Move the timer IRQs into arch_timer_vm_data KVM: arm64: timers: Abstract per-timer IRQ access KVM: arm64: timers: Rationalise per-vcpu timer init KVM: arm64: timers: Allow save/restoring of the physical timer KVM: arm64: timers: Allow userspace to set the global counter offset KVM: arm64: Expose {un,}lock_all_vcpus() to the rest of KVM KVM: arm64: timers: Allow physical offset without CNTPOFF_EL2 KVM: arm64: timers: Use CNTPOFF_EL2 to offset the physical timer arm64: Add HAS_ECV_CNTPOFF capability arm64: Add CNTPOFF_EL2 register definition ... Signed-off-by: Marc Zyngier

KVM: arm64: nv: timers: Support hyp timer emulation

2023-03-30T18:01:10+00:00

Emulating EL2 also means emulating the EL2 timers. To do so, we expand our timer framework to deal with at most 4 timers. At any given time, two timers are using the HW timers, and the two others are purely emulated. The role of deciding which is which at any given time is left to a mapping function which is called every time we need to make such a decision. Reviewed-by: Colton Lewis Co-developed-by: Christoffer Dall Signed-off-by: Christoffer Dall Signed-off-by: Marc Zyngier Link: https://lore.kernel.org/r/20230330174800.2677007-18-maz@kernel.org

KVM: arm64: nv: timers: Add a per-timer, per-vcpu offset

2023-03-30T18:01:10+00:00

Being able to set a global offset isn't enough. With NV, we also need to a per-vcpu, per-timer offset (for example, CNTVCT_EL0 being offset by CNTVOFF_EL2). Use a similar method as the VM-wide offset to have a timer point to the shadow register that contains the offset value. Reviewed-by: Colton Lewis Signed-off-by: Marc Zyngier Link: https://lore.kernel.org/r/20230330174800.2677007-17-maz@kernel.org

KVM: arm64: timers: Move the timer IRQs into arch_timer_vm_data

2023-03-30T18:01:10+00:00

Having the timer IRQs duplicated into each vcpu isn't great, and becomes absolutely awful with NV. So let's move these into the per-VM arch_timer_vm_data structure. This simplifies a lot of code, but requires us to introduce a mutex so that we can reason about userspace trying to change an interrupt number while another vcpu is running, something that wasn't really well handled so far. Reviewed-by: Colton Lewis Signed-off-by: Marc Zyngier Link: https://lore.kernel.org/r/20230330174800.2677007-12-maz@kernel.org

KVM: arm64: timers: Abstract per-timer IRQ access

2023-03-30T18:01:10+00:00

As we are about to move the location of the per-timer IRQ into the VM structure, abstract the location of the IRQ behind an accessor. This will make the repainting sligntly less painful. Reviewed-by: Colton Lewis Signed-off-by: Marc Zyngier Link: https://lore.kernel.org/r/20230330174800.2677007-11-maz@kernel.org

KVM: arm64: timers: Rationalise per-vcpu timer init

2023-03-30T18:01:10+00:00

The way we initialise our timer contexts may be satisfactory for two timers, but will be getting pretty annoying with four. Cleanup the whole thing by removing the code duplication and getting rid of unused IRQ configuration elements. Reviewed-by: Colton Lewis Signed-off-by: Marc Zyngier Link: https://lore.kernel.org/r/20230330174800.2677007-10-maz@kernel.org

KVM: arm64: timers: Use CNTPOFF_EL2 to offset the physical timer

2023-03-30T18:01:09+00:00

With ECV and CNTPOFF_EL2, it is very easy to offer an offset for the physical timer. So let's do just that. Nothing can set the offset yet, so this should have no effect whatsoever (famous last words...). Reviewed-by: Colton Lewis Signed-off-by: Marc Zyngier Link: https://lore.kernel.org/r/20230330174800.2677007-5-maz@kernel.org