| Message ID | 1461568306-14624-3-git-send-email-zhaoshenglong@huawei.com |
|---|---|
| State | Superseded |
| Headers | show |
On Mon, Apr 25, 2016 at 03:11:45PM +0800, Shannon Zhao wrote: > From: Shannon Zhao <shannon.zhao@linaro.org> > > Add a virtual PMU device for virt machine while use PPI 7 for PMU > overflow interrupt number. > > Signed-off-by: Shannon Zhao <shannon.zhao@linaro.org> > --- > hw/arm/virt.c | 34 ++++++++++++++++++++++++++++++++++ > include/hw/arm/virt.h | 4 ++++ > include/sysemu/kvm.h | 1 + > stubs/kvm.c | 5 +++++ > target-arm/kvm64.c | 39 +++++++++++++++++++++++++++++++++++++++ > 5 files changed, 83 insertions(+) > > diff --git a/hw/arm/virt.c b/hw/arm/virt.c > index 56d35c7..c3632d8 100644 > --- a/hw/arm/virt.c > +++ b/hw/arm/virt.c > @@ -428,6 +428,38 @@ static void fdt_add_gic_node(VirtBoardInfo *vbi, int type) > qemu_fdt_setprop_cell(vbi->fdt, "/intc", "phandle", vbi->gic_phandle); > } > > +static void fdt_add_pmu_nodes(const VirtBoardInfo *vbi, int gictype) > +{ > + CPUState *cpu; > + ARMCPU *armcpu; > + uint32_t irqflags = GIC_FDT_IRQ_FLAGS_LEVEL_HI; > + > + CPU_FOREACH(cpu) { > + armcpu = ARM_CPU(cpu); > + if (!armcpu->has_pmu) { > + return; > + } > + > + kvm_arm_pmu_create(cpu, PPI(VIRTUAL_PMU_IRQ)); I think we need to return a failure code from kvm_arm_pmu_create, and then do if (!kvm_arm_pmu_create(...)) { return; } Otherwise we create a /pmu node for the guest that won't work. > + } > + > + if (gictype == 2) { > + irqflags = deposit32(irqflags, GIC_FDT_IRQ_PPI_CPU_START, > + GIC_FDT_IRQ_PPI_CPU_WIDTH, > + (1 << vbi->smp_cpus) - 1); So, if we're using gicv3, then we're level triggered and these cpu mask bits aren't defined by the arm,gic-v3.txt bindings spec. Good. If we're using gicv2, then we're edge triggered and this mask is defined. Assuming the GIC implementation requires using edge triggered interrupts (as the comment in fdt_add_timer_nodes says), then OK. > + } > + > + armcpu = ARM_CPU(qemu_get_cpu(0)); > + qemu_fdt_add_subnode(vbi->fdt, "/pmu"); > + if (arm_feature(&armcpu->env, ARM_FEATURE_V8)) { > + const char compat[] = "arm,armv8-pmuv3"; > + qemu_fdt_setprop(vbi->fdt, "/pmu", "compatible", > + compat, sizeof(compat)); > + qemu_fdt_setprop_cells(vbi->fdt, "/pmu", "interrupts", > + GIC_FDT_IRQ_TYPE_PPI, VIRTUAL_PMU_IRQ, irqflags); > + } > +} > + > static void create_v2m(VirtBoardInfo *vbi, qemu_irq *pic) > { > int i; > @@ -1246,6 +1278,8 @@ static void machvirt_init(MachineState *machine) > > create_gic(vbi, pic, gic_version, vms->secure); > > + fdt_add_pmu_nodes(vbi, gic_version); > + > create_uart(vbi, pic, VIRT_UART, sysmem); > > if (vms->secure) { > diff --git a/include/hw/arm/virt.h b/include/hw/arm/virt.h > index ecd8589..b50f095 100644 > --- a/include/hw/arm/virt.h > +++ b/include/hw/arm/virt.h > @@ -40,6 +40,10 @@ > #define ARCH_TIMER_NS_EL1_IRQ 14 > #define ARCH_TIMER_NS_EL2_IRQ 10 > > +#define VIRTUAL_PMU_IRQ 7 > + > +#define PPI(irq) ((irq) + 16) > + > enum { > VIRT_FLASH, > VIRT_MEM, > diff --git a/include/sysemu/kvm.h b/include/sysemu/kvm.h > index 0e18f15..90c2c54 100644 > --- a/include/sysemu/kvm.h > +++ b/include/sysemu/kvm.h > @@ -523,4 +523,5 @@ int kvm_set_one_reg(CPUState *cs, uint64_t id, void *source); > * Returns: 0 on success, or a negative errno on failure. > */ > int kvm_get_one_reg(CPUState *cs, uint64_t id, void *target); > +void kvm_arm_pmu_create(CPUState *cs, int irq); > #endif > diff --git a/stubs/kvm.c b/stubs/kvm.c > index ddd6204..58a348a 100644 > --- a/stubs/kvm.c > +++ b/stubs/kvm.c > @@ -6,3 +6,8 @@ int kvm_arch_irqchip_create(MachineState *ms, KVMState *s) > { > return 0; > } > + > +void kvm_arm_pmu_create(CPUState *cs, int irq) > +{ > + return; > +} > diff --git a/target-arm/kvm64.c b/target-arm/kvm64.c > index b364789..22fe2a3 100644 > --- a/target-arm/kvm64.c > +++ b/target-arm/kvm64.c > @@ -382,6 +382,45 @@ static CPUWatchpoint *find_hw_watchpoint(CPUState *cpu, target_ulong addr) > return NULL; > } > > +static bool kvm_arm_pmu_support_ctrl(CPUState *cs, struct kvm_device_attr *attr) > +{ > + return kvm_vcpu_ioctl(cs, KVM_HAS_DEVICE_ATTR, attr) == 0; > +} > + > +void kvm_arm_pmu_create(CPUState *cs, int irq) > +{ > + int err; > + > + struct kvm_device_attr attr = { > + .group = KVM_ARM_VCPU_PMU_V3_CTRL, > + .addr = (intptr_t)&irq, > + .attr = KVM_ARM_VCPU_PMU_V3_IRQ, > + .flags = 0, > + }; > + > + if (!kvm_arm_pmu_support_ctrl(cs, &attr)) { > + return; > + } > + > + err = kvm_vcpu_ioctl(cs, KVM_SET_DEVICE_ATTR, &attr); > + if (err < 0) { > + fprintf(stderr, "KVM_SET_DEVICE_ATTR failed: %s\n", > + strerror(-err)); > + abort(); > + } > + > + attr.group = KVM_ARM_VCPU_PMU_V3_CTRL; > + attr.attr = KVM_ARM_VCPU_PMU_V3_INIT; > + attr.addr = 0; > + attr.flags = 0; > + > + err = kvm_vcpu_ioctl(cs, KVM_SET_DEVICE_ATTR, &attr); > + if (err < 0) { > + fprintf(stderr, "KVM_SET_DEVICE_ATTR failed: %s\n", > + strerror(-err)); > + abort(); > + } > +} > > static inline void set_feature(uint64_t *features, int feature) > { > -- > 2.0.4 > > > Thanks, drew
On Mon, Apr 25, 2016 at 07:37:13PM +0800, Shannon Zhao wrote: > > > On 2016/4/25 17:22, Andrew Jones wrote: > > On Mon, Apr 25, 2016 at 03:11:45PM +0800, Shannon Zhao wrote: > >> > From: Shannon Zhao <shannon.zhao@linaro.org> > >> > > >> > Add a virtual PMU device for virt machine while use PPI 7 for PMU > >> > overflow interrupt number. > >> > > >> > Signed-off-by: Shannon Zhao <shannon.zhao@linaro.org> > >> > --- > >> > hw/arm/virt.c | 34 ++++++++++++++++++++++++++++++++++ > >> > include/hw/arm/virt.h | 4 ++++ > >> > include/sysemu/kvm.h | 1 + > >> > stubs/kvm.c | 5 +++++ > >> > target-arm/kvm64.c | 39 +++++++++++++++++++++++++++++++++++++++ > >> > 5 files changed, 83 insertions(+) > >> > > >> > diff --git a/hw/arm/virt.c b/hw/arm/virt.c > >> > index 56d35c7..c3632d8 100644 > >> > --- a/hw/arm/virt.c > >> > +++ b/hw/arm/virt.c > >> > @@ -428,6 +428,38 @@ static void fdt_add_gic_node(VirtBoardInfo *vbi, int type) > >> > qemu_fdt_setprop_cell(vbi->fdt, "/intc", "phandle", vbi->gic_phandle); > >> > } > >> > > >> > +static void fdt_add_pmu_nodes(const VirtBoardInfo *vbi, int gictype) > >> > +{ > >> > + CPUState *cpu; > >> > + ARMCPU *armcpu; > >> > + uint32_t irqflags = GIC_FDT_IRQ_FLAGS_LEVEL_HI; > >> > + > >> > + CPU_FOREACH(cpu) { > >> > + armcpu = ARM_CPU(cpu); > >> > + if (!armcpu->has_pmu) { > >> > + return; > >> > + } > >> > + > >> > + kvm_arm_pmu_create(cpu, PPI(VIRTUAL_PMU_IRQ)); > > I think we need to return a failure code from kvm_arm_pmu_create, and > > then do > > > > if (!kvm_arm_pmu_create(...)) { > > return; > > } > > > > Otherwise we create a /pmu node for the guest that won't work. > > > Ok, will update. > > >> > + } > >> > + > >> > + if (gictype == 2) { > >> > + irqflags = deposit32(irqflags, GIC_FDT_IRQ_PPI_CPU_START, > >> > + GIC_FDT_IRQ_PPI_CPU_WIDTH, > >> > + (1 << vbi->smp_cpus) - 1); > > So, if we're using gicv3, then we're level triggered and these cpu > > mask bits aren't defined by the arm,gic-v3.txt bindings spec. Good. > > > > If we're using gicv2, then we're edge triggered and this mask is > > defined. Assuming the GIC implementation requires using edge > > triggered interrupts (as the comment in fdt_add_timer_nodes says), > > then OK. > > > IIRC the comments in fdt_add_timer_nodes are not correct now since KVM > makes PPI level triggered. > > /* Note that on A15 h/w these interrupts are level-triggered, > * but for the GIC implementation provided by both QEMU and KVM > * they are edge-triggered. > */ OK, in that case the comment should be updated to say something like "used to", but I suspect it's too late for the timer to switch to level at this point anyway, unless KVM can be probed to determine if level is OK. However, for PMU, we know that if the PMU feature exists, then level is OK, so if we want a level triggered interrupt for PMU, then we should change the giv2 irqflags assignment to an '|=' of the cpu mask. Thanks, drew
On 2016年04月25日 19:52, Andrew Jones wrote: > On Mon, Apr 25, 2016 at 07:37:13PM +0800, Shannon Zhao wrote: >> > >> > >> > On 2016/4/25 17:22, Andrew Jones wrote: >>> > > On Mon, Apr 25, 2016 at 03:11:45PM +0800, Shannon Zhao wrote: >>>>> > >> > From: Shannon Zhao <shannon.zhao@linaro.org> >>>>> > >> > >>>>> > >> > Add a virtual PMU device for virt machine while use PPI 7 for PMU >>>>> > >> > overflow interrupt number. >>>>> > >> > >>>>> > >> > Signed-off-by: Shannon Zhao <shannon.zhao@linaro.org> >>>>> > >> > --- >>>>> > >> > hw/arm/virt.c | 34 ++++++++++++++++++++++++++++++++++ >>>>> > >> > include/hw/arm/virt.h | 4 ++++ >>>>> > >> > include/sysemu/kvm.h | 1 + >>>>> > >> > stubs/kvm.c | 5 +++++ >>>>> > >> > target-arm/kvm64.c | 39 +++++++++++++++++++++++++++++++++++++++ >>>>> > >> > 5 files changed, 83 insertions(+) >>>>> > >> > >>>>> > >> > diff --git a/hw/arm/virt.c b/hw/arm/virt.c >>>>> > >> > index 56d35c7..c3632d8 100644 >>>>> > >> > --- a/hw/arm/virt.c >>>>> > >> > +++ b/hw/arm/virt.c >>>>> > >> > @@ -428,6 +428,38 @@ static void fdt_add_gic_node(VirtBoardInfo *vbi, int type) >>>>> > >> > qemu_fdt_setprop_cell(vbi->fdt, "/intc", "phandle", vbi->gic_phandle); >>>>> > >> > } >>>>> > >> > >>>>> > >> > +static void fdt_add_pmu_nodes(const VirtBoardInfo *vbi, int gictype) >>>>> > >> > +{ >>>>> > >> > + CPUState *cpu; >>>>> > >> > + ARMCPU *armcpu; >>>>> > >> > + uint32_t irqflags = GIC_FDT_IRQ_FLAGS_LEVEL_HI; >>>>> > >> > + >>>>> > >> > + CPU_FOREACH(cpu) { >>>>> > >> > + armcpu = ARM_CPU(cpu); >>>>> > >> > + if (!armcpu->has_pmu) { >>>>> > >> > + return; >>>>> > >> > + } >>>>> > >> > + >>>>> > >> > + kvm_arm_pmu_create(cpu, PPI(VIRTUAL_PMU_IRQ)); >>> > > I think we need to return a failure code from kvm_arm_pmu_create, and >>> > > then do >>> > > >>> > > if (!kvm_arm_pmu_create(...)) { >>> > > return; >>> > > } >>> > > >>> > > Otherwise we create a /pmu node for the guest that won't work. >>> > > >> > Ok, will update. >> > >>>>> > >> > + } >>>>> > >> > + >>>>> > >> > + if (gictype == 2) { >>>>> > >> > + irqflags = deposit32(irqflags, GIC_FDT_IRQ_PPI_CPU_START, >>>>> > >> > + GIC_FDT_IRQ_PPI_CPU_WIDTH, >>>>> > >> > + (1 << vbi->smp_cpus) - 1); >>> > > So, if we're using gicv3, then we're level triggered and these cpu >>> > > mask bits aren't defined by the arm,gic-v3.txt bindings spec. Good. >>> > > >>> > > If we're using gicv2, then we're edge triggered and this mask is >>> > > defined. Assuming the GIC implementation requires using edge >>> > > triggered interrupts (as the comment in fdt_add_timer_nodes says), >>> > > then OK. >>> > > >> > IIRC the comments in fdt_add_timer_nodes are not correct now since KVM >> > makes PPI level triggered. >> > >> > /* Note that on A15 h/w these interrupts are level-triggered, >> > * but for the GIC implementation provided by both QEMU and KVM >> > * they are edge-triggered. >> > */ > OK, in that case the comment should be updated to say something like > "used to", but I suspect it's too late for the timer to switch to > level at this point anyway, unless KVM can be probed to determine if > level is OK. > > However, for PMU, we know that if the PMU feature exists, then level is > OK, so if we want a level triggered interrupt for PMU, then we should > change the giv2 irqflags assignment to an '|=' of the cpu mask. Since for gicv2, the maximum of vbi->smp_cpus is 8, so it will not overflow and the result of deposit32 is right, I think. Thanks, -- Shannon
On Mon, Apr 25, 2016 at 09:54:50PM +0800, Shannon Zhao wrote: > On 2016年04月25日 19:52, Andrew Jones wrote: > > On Mon, Apr 25, 2016 at 07:37:13PM +0800, Shannon Zhao wrote: > >> > > >> > > >> > On 2016/4/25 17:22, Andrew Jones wrote: > >>> > > On Mon, Apr 25, 2016 at 03:11:45PM +0800, Shannon Zhao wrote: > >>>>> > >> > From: Shannon Zhao <shannon.zhao@linaro.org> > >>>>> > >> > > >>>>> > >> > Add a virtual PMU device for virt machine while use PPI 7 for PMU > >>>>> > >> > overflow interrupt number. > >>>>> > >> > > >>>>> > >> > Signed-off-by: Shannon Zhao <shannon.zhao@linaro.org> > >>>>> > >> > --- > >>>>> > >> > hw/arm/virt.c | 34 ++++++++++++++++++++++++++++++++++ > >>>>> > >> > include/hw/arm/virt.h | 4 ++++ > >>>>> > >> > include/sysemu/kvm.h | 1 + > >>>>> > >> > stubs/kvm.c | 5 +++++ > >>>>> > >> > target-arm/kvm64.c | 39 +++++++++++++++++++++++++++++++++++++++ > >>>>> > >> > 5 files changed, 83 insertions(+) > >>>>> > >> > > >>>>> > >> > diff --git a/hw/arm/virt.c b/hw/arm/virt.c > >>>>> > >> > index 56d35c7..c3632d8 100644 > >>>>> > >> > --- a/hw/arm/virt.c > >>>>> > >> > +++ b/hw/arm/virt.c > >>>>> > >> > @@ -428,6 +428,38 @@ static void fdt_add_gic_node(VirtBoardInfo *vbi, int type) > >>>>> > >> > qemu_fdt_setprop_cell(vbi->fdt, "/intc", "phandle", vbi->gic_phandle); > >>>>> > >> > } > >>>>> > >> > > >>>>> > >> > +static void fdt_add_pmu_nodes(const VirtBoardInfo *vbi, int gictype) > >>>>> > >> > +{ > >>>>> > >> > + CPUState *cpu; > >>>>> > >> > + ARMCPU *armcpu; > >>>>> > >> > + uint32_t irqflags = GIC_FDT_IRQ_FLAGS_LEVEL_HI; > >>>>> > >> > + > >>>>> > >> > + CPU_FOREACH(cpu) { > >>>>> > >> > + armcpu = ARM_CPU(cpu); > >>>>> > >> > + if (!armcpu->has_pmu) { > >>>>> > >> > + return; > >>>>> > >> > + } > >>>>> > >> > + > >>>>> > >> > + kvm_arm_pmu_create(cpu, PPI(VIRTUAL_PMU_IRQ)); > >>> > > I think we need to return a failure code from kvm_arm_pmu_create, and > >>> > > then do > >>> > > > >>> > > if (!kvm_arm_pmu_create(...)) { > >>> > > return; > >>> > > } > >>> > > > >>> > > Otherwise we create a /pmu node for the guest that won't work. > >>> > > > >> > Ok, will update. > >> > > >>>>> > >> > + } > >>>>> > >> > + > >>>>> > >> > + if (gictype == 2) { > >>>>> > >> > + irqflags = deposit32(irqflags, GIC_FDT_IRQ_PPI_CPU_START, > >>>>> > >> > + GIC_FDT_IRQ_PPI_CPU_WIDTH, > >>>>> > >> > + (1 << vbi->smp_cpus) - 1); > >>> > > So, if we're using gicv3, then we're level triggered and these cpu > >>> > > mask bits aren't defined by the arm,gic-v3.txt bindings spec. Good. > >>> > > > >>> > > If we're using gicv2, then we're edge triggered and this mask is > >>> > > defined. Assuming the GIC implementation requires using edge > >>> > > triggered interrupts (as the comment in fdt_add_timer_nodes says), > >>> > > then OK. > >>> > > > >> > IIRC the comments in fdt_add_timer_nodes are not correct now since KVM > >> > makes PPI level triggered. > >> > > >> > /* Note that on A15 h/w these interrupts are level-triggered, > >> > * but for the GIC implementation provided by both QEMU and KVM > >> > * they are edge-triggered. > >> > */ > > OK, in that case the comment should be updated to say something like > > "used to", but I suspect it's too late for the timer to switch to > > level at this point anyway, unless KVM can be probed to determine if > > level is OK. > > > > However, for PMU, we know that if the PMU feature exists, then level is > > OK, so if we want a level triggered interrupt for PMU, then we should > > change the giv2 irqflags assignment to an '|=' of the cpu mask. > Since for gicv2, the maximum of vbi->smp_cpus is 8, so it will not > overflow and the result of deposit32 is right, I think. Yes. I was actually referring to the level flag, thinking it was getting overwritten with zero, but now I see in deposit32's description that "Bits of @value outside the bit field are not modified." So this is fine. Thanks, drew
diff --git a/hw/arm/virt.c b/hw/arm/virt.c index 56d35c7..c3632d8 100644 --- a/hw/arm/virt.c +++ b/hw/arm/virt.c @@ -428,6 +428,38 @@ static void fdt_add_gic_node(VirtBoardInfo *vbi, int type) qemu_fdt_setprop_cell(vbi->fdt, "/intc", "phandle", vbi->gic_phandle); } +static void fdt_add_pmu_nodes(const VirtBoardInfo *vbi, int gictype) +{ + CPUState *cpu; + ARMCPU *armcpu; + uint32_t irqflags = GIC_FDT_IRQ_FLAGS_LEVEL_HI; + + CPU_FOREACH(cpu) { + armcpu = ARM_CPU(cpu); + if (!armcpu->has_pmu) { + return; + } + + kvm_arm_pmu_create(cpu, PPI(VIRTUAL_PMU_IRQ)); + } + + if (gictype == 2) { + irqflags = deposit32(irqflags, GIC_FDT_IRQ_PPI_CPU_START, + GIC_FDT_IRQ_PPI_CPU_WIDTH, + (1 << vbi->smp_cpus) - 1); + } + + armcpu = ARM_CPU(qemu_get_cpu(0)); + qemu_fdt_add_subnode(vbi->fdt, "/pmu"); + if (arm_feature(&armcpu->env, ARM_FEATURE_V8)) { + const char compat[] = "arm,armv8-pmuv3"; + qemu_fdt_setprop(vbi->fdt, "/pmu", "compatible", + compat, sizeof(compat)); + qemu_fdt_setprop_cells(vbi->fdt, "/pmu", "interrupts", + GIC_FDT_IRQ_TYPE_PPI, VIRTUAL_PMU_IRQ, irqflags); + } +} + static void create_v2m(VirtBoardInfo *vbi, qemu_irq *pic) { int i; @@ -1246,6 +1278,8 @@ static void machvirt_init(MachineState *machine) create_gic(vbi, pic, gic_version, vms->secure); + fdt_add_pmu_nodes(vbi, gic_version); + create_uart(vbi, pic, VIRT_UART, sysmem); if (vms->secure) { diff --git a/include/hw/arm/virt.h b/include/hw/arm/virt.h index ecd8589..b50f095 100644 --- a/include/hw/arm/virt.h +++ b/include/hw/arm/virt.h @@ -40,6 +40,10 @@ #define ARCH_TIMER_NS_EL1_IRQ 14 #define ARCH_TIMER_NS_EL2_IRQ 10 +#define VIRTUAL_PMU_IRQ 7 + +#define PPI(irq) ((irq) + 16) + enum { VIRT_FLASH, VIRT_MEM, diff --git a/include/sysemu/kvm.h b/include/sysemu/kvm.h index 0e18f15..90c2c54 100644 --- a/include/sysemu/kvm.h +++ b/include/sysemu/kvm.h @@ -523,4 +523,5 @@ int kvm_set_one_reg(CPUState *cs, uint64_t id, void *source); * Returns: 0 on success, or a negative errno on failure. */ int kvm_get_one_reg(CPUState *cs, uint64_t id, void *target); +void kvm_arm_pmu_create(CPUState *cs, int irq); #endif diff --git a/stubs/kvm.c b/stubs/kvm.c index ddd6204..58a348a 100644 --- a/stubs/kvm.c +++ b/stubs/kvm.c @@ -6,3 +6,8 @@ int kvm_arch_irqchip_create(MachineState *ms, KVMState *s) { return 0; } + +void kvm_arm_pmu_create(CPUState *cs, int irq) +{ + return; +} diff --git a/target-arm/kvm64.c b/target-arm/kvm64.c index b364789..22fe2a3 100644 --- a/target-arm/kvm64.c +++ b/target-arm/kvm64.c @@ -382,6 +382,45 @@ static CPUWatchpoint *find_hw_watchpoint(CPUState *cpu, target_ulong addr) return NULL; } +static bool kvm_arm_pmu_support_ctrl(CPUState *cs, struct kvm_device_attr *attr) +{ + return kvm_vcpu_ioctl(cs, KVM_HAS_DEVICE_ATTR, attr) == 0; +} + +void kvm_arm_pmu_create(CPUState *cs, int irq) +{ + int err; + + struct kvm_device_attr attr = { + .group = KVM_ARM_VCPU_PMU_V3_CTRL, + .addr = (intptr_t)&irq, + .attr = KVM_ARM_VCPU_PMU_V3_IRQ, + .flags = 0, + }; + + if (!kvm_arm_pmu_support_ctrl(cs, &attr)) { + return; + } + + err = kvm_vcpu_ioctl(cs, KVM_SET_DEVICE_ATTR, &attr); + if (err < 0) { + fprintf(stderr, "KVM_SET_DEVICE_ATTR failed: %s\n", + strerror(-err)); + abort(); + } + + attr.group = KVM_ARM_VCPU_PMU_V3_CTRL; + attr.attr = KVM_ARM_VCPU_PMU_V3_INIT; + attr.addr = 0; + attr.flags = 0; + + err = kvm_vcpu_ioctl(cs, KVM_SET_DEVICE_ATTR, &attr); + if (err < 0) { + fprintf(stderr, "KVM_SET_DEVICE_ATTR failed: %s\n", + strerror(-err)); + abort(); + } +} static inline void set_feature(uint64_t *features, int feature) {