linux/include/kvm/arm_pmu.h
Zenghui Yu bca031e2c8 KVM: arm/arm64: Introduce kvm_pmu_vcpu_init() to setup PMU counter index
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: 80f393a23b ("KVM: arm/arm64: Support chained PMU counters")
Suggested-by: Andrew Murray <andrew.murray@arm.com>
Suggested-by: Julien Thierry <julien.thierry@arm.com>
Acked-by: Julien Thierry <julien.thierry@arm.com>
Signed-off-by: Zenghui Yu <yuzenghui@huawei.com>
Signed-off-by: Marc Zyngier <marc.zyngier@arm.com>
2019-07-23 09:23:44 +01:00

114 lines
3.8 KiB
C

/* SPDX-License-Identifier: GPL-2.0-only */
/*
* Copyright (C) 2015 Linaro Ltd.
* Author: Shannon Zhao <shannon.zhao@linaro.org>
*/
#ifndef __ASM_ARM_KVM_PMU_H
#define __ASM_ARM_KVM_PMU_H
#include <linux/perf_event.h>
#include <asm/perf_event.h>
#define ARMV8_PMU_CYCLE_IDX (ARMV8_PMU_MAX_COUNTERS - 1)
#define ARMV8_PMU_MAX_COUNTER_PAIRS ((ARMV8_PMU_MAX_COUNTERS + 1) >> 1)
#ifdef CONFIG_KVM_ARM_PMU
struct kvm_pmc {
u8 idx; /* index into the pmu->pmc array */
struct perf_event *perf_event;
};
struct kvm_pmu {
int irq_num;
struct kvm_pmc pmc[ARMV8_PMU_MAX_COUNTERS];
DECLARE_BITMAP(chained, ARMV8_PMU_MAX_COUNTER_PAIRS);
bool ready;
bool created;
bool irq_level;
};
#define kvm_arm_pmu_v3_ready(v) ((v)->arch.pmu.ready)
#define kvm_arm_pmu_irq_initialized(v) ((v)->arch.pmu.irq_num >= VGIC_NR_SGIS)
u64 kvm_pmu_get_counter_value(struct kvm_vcpu *vcpu, u64 select_idx);
void kvm_pmu_set_counter_value(struct kvm_vcpu *vcpu, u64 select_idx, u64 val);
u64 kvm_pmu_valid_counter_mask(struct kvm_vcpu *vcpu);
void kvm_pmu_vcpu_init(struct kvm_vcpu *vcpu);
void kvm_pmu_vcpu_reset(struct kvm_vcpu *vcpu);
void kvm_pmu_vcpu_destroy(struct kvm_vcpu *vcpu);
void kvm_pmu_disable_counter_mask(struct kvm_vcpu *vcpu, u64 val);
void kvm_pmu_enable_counter_mask(struct kvm_vcpu *vcpu, u64 val);
void kvm_pmu_flush_hwstate(struct kvm_vcpu *vcpu);
void kvm_pmu_sync_hwstate(struct kvm_vcpu *vcpu);
bool kvm_pmu_should_notify_user(struct kvm_vcpu *vcpu);
void kvm_pmu_update_run(struct kvm_vcpu *vcpu);
void kvm_pmu_software_increment(struct kvm_vcpu *vcpu, u64 val);
void kvm_pmu_handle_pmcr(struct kvm_vcpu *vcpu, u64 val);
void kvm_pmu_set_counter_event_type(struct kvm_vcpu *vcpu, u64 data,
u64 select_idx);
bool kvm_arm_support_pmu_v3(void);
int kvm_arm_pmu_v3_set_attr(struct kvm_vcpu *vcpu,
struct kvm_device_attr *attr);
int kvm_arm_pmu_v3_get_attr(struct kvm_vcpu *vcpu,
struct kvm_device_attr *attr);
int kvm_arm_pmu_v3_has_attr(struct kvm_vcpu *vcpu,
struct kvm_device_attr *attr);
int kvm_arm_pmu_v3_enable(struct kvm_vcpu *vcpu);
#else
struct kvm_pmu {
};
#define kvm_arm_pmu_v3_ready(v) (false)
#define kvm_arm_pmu_irq_initialized(v) (false)
static inline u64 kvm_pmu_get_counter_value(struct kvm_vcpu *vcpu,
u64 select_idx)
{
return 0;
}
static inline void kvm_pmu_set_counter_value(struct kvm_vcpu *vcpu,
u64 select_idx, u64 val) {}
static inline u64 kvm_pmu_valid_counter_mask(struct kvm_vcpu *vcpu)
{
return 0;
}
static inline void kvm_pmu_vcpu_init(struct kvm_vcpu *vcpu) {}
static inline void kvm_pmu_vcpu_reset(struct kvm_vcpu *vcpu) {}
static inline void kvm_pmu_vcpu_destroy(struct kvm_vcpu *vcpu) {}
static inline void kvm_pmu_disable_counter_mask(struct kvm_vcpu *vcpu, u64 val) {}
static inline void kvm_pmu_enable_counter_mask(struct kvm_vcpu *vcpu, u64 val) {}
static inline void kvm_pmu_flush_hwstate(struct kvm_vcpu *vcpu) {}
static inline void kvm_pmu_sync_hwstate(struct kvm_vcpu *vcpu) {}
static inline bool kvm_pmu_should_notify_user(struct kvm_vcpu *vcpu)
{
return false;
}
static inline void kvm_pmu_update_run(struct kvm_vcpu *vcpu) {}
static inline void kvm_pmu_software_increment(struct kvm_vcpu *vcpu, u64 val) {}
static inline void kvm_pmu_handle_pmcr(struct kvm_vcpu *vcpu, u64 val) {}
static inline void kvm_pmu_set_counter_event_type(struct kvm_vcpu *vcpu,
u64 data, u64 select_idx) {}
static inline bool kvm_arm_support_pmu_v3(void) { return false; }
static inline int kvm_arm_pmu_v3_set_attr(struct kvm_vcpu *vcpu,
struct kvm_device_attr *attr)
{
return -ENXIO;
}
static inline int kvm_arm_pmu_v3_get_attr(struct kvm_vcpu *vcpu,
struct kvm_device_attr *attr)
{
return -ENXIO;
}
static inline int kvm_arm_pmu_v3_has_attr(struct kvm_vcpu *vcpu,
struct kvm_device_attr *attr)
{
return -ENXIO;
}
static inline int kvm_arm_pmu_v3_enable(struct kvm_vcpu *vcpu)
{
return 0;
}
#endif
#endif