kernel/linux.git/include/kvm/arm_pmu.h, branch v5.9.2

KVM: arm/arm64: Introduce kvm_pmu_vcpu_init() to setup PMU counter index

2019-07-23T08:23:44+00:00

We use "pmc->idx" and the "chained" bitmap to determine if the pmc is chained, in kvm_pmu_pmc_is_chained(). But idx might be uninitialized (and random) when we doing this decision, through a KVM_ARM_VCPU_INIT ioctl -> kvm_pmu_vcpu_reset(). And the test_bit() against this random idx will potentially hit a KASAN BUG [1]. In general, idx is the static property of a PMU counter that is not expected to be modified across resets, as suggested by Julien. It looks more reasonable if we can setup the PMU counter idx for a vcpu in its creation time. Introduce a new function - kvm_pmu_vcpu_init() for this basic setup. Oh, and the KASAN BUG will get fixed this way. [1] https://www.spinics.net/lists/kvm-arm/msg36700.html Fixes: 80f393a23be6 ("KVM: arm/arm64: Support chained PMU counters") Suggested-by: Andrew Murray Suggested-by: Julien Thierry Acked-by: Julien Thierry Signed-off-by: Zenghui Yu Signed-off-by: Marc Zyngier

KVM: arm/arm64: Support chained PMU counters

2019-07-05T12:56:22+00:00

ARMv8 provides support for chained PMU counters, where an event type of 0x001E is set for odd-numbered counters, the event counter will increment by one for each overflow of the preceding even-numbered counter. Let's emulate this in KVM by creating a 64 bit perf counter when a user chains two emulated counters together. For chained events we only support generating an overflow interrupt on the high counter. We use the attributes of the low counter to determine the attributes of the perf event. Suggested-by: Marc Zyngier Signed-off-by: Andrew Murray Reviewed-by: Julien Thierry Reviewed-by: Suzuki K Poulose Signed-off-by: Marc Zyngier

KVM: arm/arm64: Remove pmc->bitmask

2019-07-05T12:56:18+00:00

We currently use pmc->bitmask to determine the width of the pmc - however it's superfluous as the pmc index already describes if the pmc is a cycle counter or event counter. The architecture clearly describes the widths of these counters. Let's remove the bitmask to simplify the code. Signed-off-by: Andrew Murray Signed-off-by: Marc Zyngier

KVM: arm/arm64: Rename kvm_pmu_{enable/disable}_counter functions

2019-07-05T12:56:04+00:00

The kvm_pmu_{enable/disable}_counter functions can enable/disable multiple counters at once as they operate on a bitmask. Let's make this clearer by renaming the function. Suggested-by: Suzuki K Poulose Signed-off-by: Andrew Murray Reviewed-by: Julien Thierry Reviewed-by: Suzuki K Poulose Signed-off-by: Marc Zyngier

treewide: Replace GPLv2 boilerplate/reference with SPDX - rule 234

2019-06-19T15:09:07+00:00

Based on 1 normalized pattern(s): this program is free software you can redistribute it and or modify it under the terms of the gnu general public license version 2 as published by the free software foundation this program is distributed in the hope that it will be useful but without any warranty without even the implied warranty of merchantability or fitness for a particular purpose see the gnu general public license for more details you should have received a copy of the gnu general public license along with this program if not see http www gnu org licenses extracted by the scancode license scanner the SPDX license identifier GPL-2.0-only has been chosen to replace the boilerplate/reference in 503 file(s). Signed-off-by: Thomas Gleixner Reviewed-by: Alexios Zavras Reviewed-by: Allison Randal Reviewed-by: Enrico Weigelt Cc: linux-spdx@vger.kernel.org Link: https://lkml.kernel.org/r/20190602204653.811534538@linutronix.de Signed-off-by: Greg Kroah-Hartman

KVM: arm/arm64: PMU: Fix overflow interrupt injection

2017-07-25T13:18:01+00:00

kvm_pmu_overflow_set() is called from perf's interrupt handler, making the call of kvm_vgic_inject_irq() from it introduced with "KVM: arm/arm64: PMU: remove request-less vcpu kick" a really bad idea, as it's quite easy to try and retake a lock that the interrupted context is already holding. The fix is to use a vcpu kick, leaving the interrupt injection to kvm_pmu_sync_hwstate(), like it was doing before the refactoring. We don't just revert, though, because before the kick was request-less, leaving the vcpu exposed to the request-less vcpu kick race, and also because the kick was used unnecessarily from register access handlers. Reviewed-by: Christoffer Dall Signed-off-by: Andrew Jones Signed-off-by: Marc Zyngier

KVM: arm64: Allow creating the PMU without the in-kernel GIC

2017-06-08T14:59:44+00:00

Since we got support for devices in userspace which allows reporting the PMU overflow output status to userspace, we should actually allow creating the PMU on systems without an in-kernel irqchip, which in turn requires us to slightly clarify error codes for the ABI and move things around for the initialization phase. Signed-off-by: Christoffer Dall Reviewed-by: Marc Zyngier

KVM: arm/arm64: Report PMU overflow interrupts to userspace irqchip

2017-04-09T14:49:39+00:00

When not using an in-kernel VGIC, but instead emulating an interrupt controller in userspace, we should report the PMU overflow status to that userspace interrupt controller using the KVM_CAP_ARM_USER_IRQ feature. Reviewed-by: Alexander Graf Reviewed-by: Marc Zyngier Signed-off-by: Christoffer Dall

arm64: KVM: fix build with CONFIG_ARM_PMU disabled

2016-06-27T10:55:51+00:00

When CONFIG_ARM_PMU is disabled, we get the following build error: arch/arm64/kvm/sys_regs.c: In function 'pmu_counter_idx_valid': arch/arm64/kvm/sys_regs.c:564:27: error: 'ARMV8_PMU_CYCLE_IDX' undeclared (first use in this function) if (idx >= val && idx != ARMV8_PMU_CYCLE_IDX) ^ arch/arm64/kvm/sys_regs.c:564:27: note: each undeclared identifier is reported only once for each function it appears in arch/arm64/kvm/sys_regs.c: In function 'access_pmu_evcntr': arch/arm64/kvm/sys_regs.c:592:10: error: 'ARMV8_PMU_CYCLE_IDX' undeclared (first use in this function) idx = ARMV8_PMU_CYCLE_IDX; ^ arch/arm64/kvm/sys_regs.c: In function 'access_pmu_evtyper': arch/arm64/kvm/sys_regs.c:638:14: error: 'ARMV8_PMU_CYCLE_IDX' undeclared (first use in this function) if (idx == ARMV8_PMU_CYCLE_IDX) ^ arch/arm64/kvm/hyp/switch.c:86:15: error: 'ARMV8_PMU_USERENR_MASK' undeclared (first use in this function) write_sysreg(ARMV8_PMU_USERENR_MASK, pmuserenr_el0); This patch fixes the build with CONFIG_ARM_PMU disabled. Cc: Christoffer Dall Cc: Marc Zyngier Signed-off-by: Sudeep Holla Signed-off-by: Christoffer Dall

arm64: KVM: Add a new vcpu device control group for PMUv3

2016-02-29T18:34:21+00:00

To configure the virtual PMUv3 overflow interrupt number, we use the vcpu kvm_device ioctl, encapsulating the KVM_ARM_VCPU_PMU_V3_IRQ attribute within the KVM_ARM_VCPU_PMU_V3_CTRL group. After configuring the PMUv3, call the vcpu ioctl with attribute KVM_ARM_VCPU_PMU_V3_INIT to initialize the PMUv3. Signed-off-by: Shannon Zhao Acked-by: Peter Maydell Reviewed-by: Andrew Jones Reviewed-by: Christoffer Dall Signed-off-by: Marc Zyngier