From 7d20e6815bf5ab678a55673224340b39218be510 Mon Sep 17 00:00:00 2001 From: =?UTF-8?q?Philippe=20Mathieu-Daud=C3=A9?= Date: Tue, 23 Jun 2020 11:06:22 +0200 Subject: [PATCH] target/arm: Check supported KVM features globally (not per vCPU) MIME-Version: 1.0 Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 8bit Since commit d70c996df23f, when enabling the PMU we get: $ qemu-system-aarch64 -cpu host,pmu=on -M virt,accel=kvm,gic-version=3 Segmentation fault (core dumped) Thread 1 "qemu-system-aar" received signal SIGSEGV, Segmentation fault. 0x0000aaaaaae356d0 in kvm_ioctl (s=0x0, type=44547) at accel/kvm/kvm-all.c:2588 2588 ret = ioctl(s->fd, type, arg); (gdb) bt #0 0x0000aaaaaae356d0 in kvm_ioctl (s=0x0, type=44547) at accel/kvm/kvm-all.c:2588 #1 0x0000aaaaaae31568 in kvm_check_extension (s=0x0, extension=126) at accel/kvm/kvm-all.c:916 #2 0x0000aaaaaafce254 in kvm_arm_pmu_supported (cpu=0xaaaaac214ab0) at target/arm/kvm.c:213 #3 0x0000aaaaaafc0f94 in arm_set_pmu (obj=0xaaaaac214ab0, value=true, errp=0xffffffffe438) at target/arm/cpu.c:1111 #4 0x0000aaaaab5533ac in property_set_bool (obj=0xaaaaac214ab0, v=0xaaaaac223a80, name=0xaaaaac11a970 "pmu", opaque=0xaaaaac222730, errp=0xffffffffe438) at qom/object.c:2170 #5 0x0000aaaaab5512f0 in object_property_set (obj=0xaaaaac214ab0, v=0xaaaaac223a80, name=0xaaaaac11a970 "pmu", errp=0xffffffffe438) at qom/object.c:1328 #6 0x0000aaaaab551e10 in object_property_parse (obj=0xaaaaac214ab0, string=0xaaaaac11b4c0 "on", name=0xaaaaac11a970 "pmu", errp=0xffffffffe438) at qom/object.c:1561 #7 0x0000aaaaab54ee8c in object_apply_global_props (obj=0xaaaaac214ab0, props=0xaaaaac018e20, errp=0xaaaaabd6fd88 ) at qom/object.c:407 #8 0x0000aaaaab1dd5a4 in qdev_prop_set_globals (dev=0xaaaaac214ab0) at hw/core/qdev-properties.c:1218 #9 0x0000aaaaab1d9fac in device_post_init (obj=0xaaaaac214ab0) at hw/core/qdev.c:1050 ... #15 0x0000aaaaab54f310 in object_initialize_with_type (obj=0xaaaaac214ab0, size=52208, type=0xaaaaabe237f0) at qom/object.c:512 #16 0x0000aaaaab54fa24 in object_new_with_type (type=0xaaaaabe237f0) at qom/object.c:687 #17 0x0000aaaaab54fa80 in object_new (typename=0xaaaaabe23970 "host-arm-cpu") at qom/object.c:702 #18 0x0000aaaaaaf04a74 in machvirt_init (machine=0xaaaaac0a8550) at hw/arm/virt.c:1770 #19 0x0000aaaaab1e8720 in machine_run_board_init (machine=0xaaaaac0a8550) at hw/core/machine.c:1138 #20 0x0000aaaaaaf95394 in qemu_init (argc=5, argv=0xffffffffea58, envp=0xffffffffea88) at softmmu/vl.c:4348 #21 0x0000aaaaaada3f74 in main (argc=, argv=, envp=) at softmmu/main.c:48 This is because in frame #2, cpu->kvm_state is still NULL (the vCPU is not yet realized). KVM has a hard requirement of all cores supporting the same feature set. We only need to check if the accelerator supports a feature, not each vCPU individually. Fix by removing the 'CPUState *cpu' argument from the kvm_arm__supported() functions. Fixes: d70c996df23f ('Use CPUState::kvm_state in kvm_arm_pmu_supported') Reported-by: Haibo Xu Reviewed-by: Andrew Jones Acked-by: Paolo Bonzini Signed-off-by: Philippe Mathieu-Daudé Suggested-by: Paolo Bonzini Signed-off-by: Philippe Mathieu-Daudé Signed-off-by: Peter Maydell --- target/arm/cpu.c | 2 +- target/arm/cpu64.c | 10 +++++----- target/arm/kvm.c | 4 ++-- target/arm/kvm64.c | 14 +++++--------- target/arm/kvm_arm.h | 21 +++++++++------------ 5 files changed, 22 insertions(+), 29 deletions(-) diff --git a/target/arm/cpu.c b/target/arm/cpu.c index 5b7a36b5d7..e44e18062c 100644 --- a/target/arm/cpu.c +++ b/target/arm/cpu.c @@ -1108,7 +1108,7 @@ static void arm_set_pmu(Object *obj, bool value, Error **errp) ARMCPU *cpu = ARM_CPU(obj); if (value) { - if (kvm_enabled() && !kvm_arm_pmu_supported(CPU(cpu))) { + if (kvm_enabled() && !kvm_arm_pmu_supported()) { error_setg(errp, "'pmu' feature not supported by KVM on this host"); return; } diff --git a/target/arm/cpu64.c b/target/arm/cpu64.c index 778cecc2e6..a0c1d8894b 100644 --- a/target/arm/cpu64.c +++ b/target/arm/cpu64.c @@ -266,7 +266,7 @@ void arm_cpu_sve_finalize(ARMCPU *cpu, Error **errp) /* Collect the set of vector lengths supported by KVM. */ bitmap_zero(kvm_supported, ARM_MAX_VQ); - if (kvm_enabled() && kvm_arm_sve_supported(CPU(cpu))) { + if (kvm_enabled() && kvm_arm_sve_supported()) { kvm_arm_sve_get_vls(CPU(cpu), kvm_supported); } else if (kvm_enabled()) { assert(!cpu_isar_feature(aa64_sve, cpu)); @@ -473,7 +473,7 @@ static void cpu_max_set_sve_max_vq(Object *obj, Visitor *v, const char *name, return; } - if (kvm_enabled() && !kvm_arm_sve_supported(CPU(cpu))) { + if (kvm_enabled() && !kvm_arm_sve_supported()) { error_setg(errp, "cannot set sve-max-vq"); error_append_hint(errp, "SVE not supported by KVM on this host\n"); return; @@ -519,7 +519,7 @@ static void cpu_arm_set_sve_vq(Object *obj, Visitor *v, const char *name, return; } - if (value && kvm_enabled() && !kvm_arm_sve_supported(CPU(cpu))) { + if (value && kvm_enabled() && !kvm_arm_sve_supported()) { error_setg(errp, "cannot enable %s", name); error_append_hint(errp, "SVE not supported by KVM on this host\n"); return; @@ -556,7 +556,7 @@ static void cpu_arm_set_sve(Object *obj, Visitor *v, const char *name, return; } - if (value && kvm_enabled() && !kvm_arm_sve_supported(CPU(cpu))) { + if (value && kvm_enabled() && !kvm_arm_sve_supported()) { error_setg(errp, "'sve' feature not supported by KVM on this host"); return; } @@ -751,7 +751,7 @@ static void aarch64_cpu_set_aarch64(Object *obj, bool value, Error **errp) * uniform execution state like do_interrupt. */ if (value == false) { - if (!kvm_enabled() || !kvm_arm_aarch32_supported(CPU(cpu))) { + if (!kvm_enabled() || !kvm_arm_aarch32_supported()) { error_setg(errp, "'aarch64' feature cannot be disabled " "unless KVM is enabled and 32-bit EL1 " "is supported"); diff --git a/target/arm/kvm.c b/target/arm/kvm.c index eef3bbd1cc..7c672c78b8 100644 --- a/target/arm/kvm.c +++ b/target/arm/kvm.c @@ -208,9 +208,9 @@ void kvm_arm_add_vcpu_properties(Object *obj) } } -bool kvm_arm_pmu_supported(CPUState *cpu) +bool kvm_arm_pmu_supported(void) { - return kvm_check_extension(cpu->kvm_state, KVM_CAP_ARM_PMU_V3); + return kvm_check_extension(kvm_state, KVM_CAP_ARM_PMU_V3); } int kvm_arm_get_max_vm_ipa_size(MachineState *ms) diff --git a/target/arm/kvm64.c b/target/arm/kvm64.c index f09ed9f4df..3dc494aaa7 100644 --- a/target/arm/kvm64.c +++ b/target/arm/kvm64.c @@ -652,18 +652,14 @@ bool kvm_arm_get_host_cpu_features(ARMHostCPUFeatures *ahcf) return true; } -bool kvm_arm_aarch32_supported(CPUState *cpu) +bool kvm_arm_aarch32_supported(void) { - KVMState *s = KVM_STATE(current_accel()); - - return kvm_check_extension(s, KVM_CAP_ARM_EL1_32BIT); + return kvm_check_extension(kvm_state, KVM_CAP_ARM_EL1_32BIT); } -bool kvm_arm_sve_supported(CPUState *cpu) +bool kvm_arm_sve_supported(void) { - KVMState *s = KVM_STATE(current_accel()); - - return kvm_check_extension(s, KVM_CAP_ARM_SVE); + return kvm_check_extension(kvm_state, KVM_CAP_ARM_SVE); } QEMU_BUILD_BUG_ON(KVM_ARM64_SVE_VQ_MIN != 1); @@ -798,7 +794,7 @@ int kvm_arch_init_vcpu(CPUState *cs) env->features &= ~(1ULL << ARM_FEATURE_PMU); } if (cpu_isar_feature(aa64_sve, cpu)) { - assert(kvm_arm_sve_supported(cs)); + assert(kvm_arm_sve_supported()); cpu->kvm_init_features[0] |= 1 << KVM_ARM_VCPU_SVE; } diff --git a/target/arm/kvm_arm.h b/target/arm/kvm_arm.h index 48bf5e16d5..a4ce4fd93d 100644 --- a/target/arm/kvm_arm.h +++ b/target/arm/kvm_arm.h @@ -269,29 +269,26 @@ void kvm_arm_add_vcpu_properties(Object *obj); /** * kvm_arm_aarch32_supported: - * @cs: CPUState * - * Returns: true if the KVM VCPU can enable AArch32 mode + * Returns: true if KVM can enable AArch32 mode * and false otherwise. */ -bool kvm_arm_aarch32_supported(CPUState *cs); +bool kvm_arm_aarch32_supported(void); /** * kvm_arm_pmu_supported: - * @cs: CPUState * - * Returns: true if the KVM VCPU can enable its PMU + * Returns: true if KVM can enable the PMU * and false otherwise. */ -bool kvm_arm_pmu_supported(CPUState *cs); +bool kvm_arm_pmu_supported(void); /** * kvm_arm_sve_supported: - * @cs: CPUState * - * Returns true if the KVM VCPU can enable SVE and false otherwise. + * Returns true if KVM can enable SVE and false otherwise. */ -bool kvm_arm_sve_supported(CPUState *cs); +bool kvm_arm_sve_supported(void); /** * kvm_arm_get_max_vm_ipa_size: @@ -359,17 +356,17 @@ static inline void kvm_arm_set_cpu_features_from_host(ARMCPU *cpu) static inline void kvm_arm_add_vcpu_properties(Object *obj) {} -static inline bool kvm_arm_aarch32_supported(CPUState *cs) +static inline bool kvm_arm_aarch32_supported(void) { return false; } -static inline bool kvm_arm_pmu_supported(CPUState *cs) +static inline bool kvm_arm_pmu_supported(void) { return false; } -static inline bool kvm_arm_sve_supported(CPUState *cs) +static inline bool kvm_arm_sve_supported(void) { return false; }