> -----Original Message----- > From: Alex Williamson [mailto:alex.williamson@xxxxxxxxxx] > Sent: Tuesday, November 11, 2014 5:57 AM > To: Wu, Feng > Cc: gleb@xxxxxxxxxx; pbonzini@xxxxxxxxxx; dwmw2@xxxxxxxxxxxxx; > joro@xxxxxxxxxx; tglx@xxxxxxxxxxxxx; mingo@xxxxxxxxxx; hpa@xxxxxxxxx; > x86@xxxxxxxxxx; kvm@xxxxxxxxxxxxxxx; iommu@xxxxxxxxxxxxxxxxxxxxxxxxxx; > linux-kernel@xxxxxxxxxxxxxxx > Subject: Re: [PATCH 02/13] KVM: Initialize VT-d Posted-Interrtups Descriptor > > On Mon, 2014-11-10 at 14:26 +0800, Feng Wu wrote: > > This patch initialize the VT-d Posted-interrupt Descritpor. > > > > Signed-off-by: Feng Wu <feng.wu@xxxxxxxxx> > > --- > > arch/x86/include/asm/irq_remapping.h | 1 + > > arch/x86/kernel/apic/apic.c | 1 + > > arch/x86/kvm/vmx.c | 56 > ++++++++++++++++++++++++++++++++- > > 3 files changed, 56 insertions(+), 2 deletions(-) > > > > diff --git a/arch/x86/include/asm/irq_remapping.h > b/arch/x86/include/asm/irq_remapping.h > > index b7747c4..a3cc437 100644 > > --- a/arch/x86/include/asm/irq_remapping.h > > +++ b/arch/x86/include/asm/irq_remapping.h > > @@ -57,6 +57,7 @@ extern bool setup_remapped_irq(int irq, > > struct irq_chip *chip); > > > > void irq_remap_modify_chip_defaults(struct irq_chip *chip); > > +extern int irq_post_enabled; > > > > #else /* CONFIG_IRQ_REMAP */ > > > > diff --git a/arch/x86/kernel/apic/apic.c b/arch/x86/kernel/apic/apic.c > > index ba6cc04..987408d 100644 > > --- a/arch/x86/kernel/apic/apic.c > > +++ b/arch/x86/kernel/apic/apic.c > > @@ -162,6 +162,7 @@ __setup("apicpmtimer", setup_apicpmtimer); > > #endif > > > > int x2apic_mode; > > +EXPORT_SYMBOL_GPL(x2apic_mode); > > #ifdef CONFIG_X86_X2APIC > > /* x2apic enabled before OS handover */ > > int x2apic_preenabled; > > diff --git a/arch/x86/kvm/vmx.c b/arch/x86/kvm/vmx.c > > index 3e556c6..a4670d3 100644 > > --- a/arch/x86/kvm/vmx.c > > +++ b/arch/x86/kvm/vmx.c > > @@ -45,6 +45,7 @@ > > #include <asm/perf_event.h> > > #include <asm/debugreg.h> > > #include <asm/kexec.h> > > +#include <asm/irq_remapping.h> > > > > #include "trace.h" > > > > @@ -408,13 +409,32 @@ struct nested_vmx { > > }; > > > > #define POSTED_INTR_ON 0 > > +#define POSTED_INTR_SN 1 > > + > > /* Posted-Interrupt Descriptor */ > > struct pi_desc { > > u32 pir[8]; /* Posted interrupt requested */ > > - u32 control; /* bit 0 of control is outstanding notification bit */ > > - u32 rsvd[7]; > > + union { > > + struct { > > + u64 on : 1, > > + sn : 1, > > + rsvd_1 : 13, > > + ndm : 1, > > + nv : 8, > > + rsvd_2 : 8, > > + ndst : 32; > > + }; > > + u64 control; > > + }; > > + u32 rsvd[6]; > > } __aligned(64); > > > > +static void pi_clear_sn(struct pi_desc *pi_desc) > > +{ > > + return clear_bit(POSTED_INTR_SN, > > + (unsigned long *)&pi_desc->control); > > +} > > + > > static bool pi_test_and_set_on(struct pi_desc *pi_desc) > > { > > return test_and_set_bit(POSTED_INTR_ON, > > @@ -4396,6 +4416,33 @@ static void ept_set_mmio_spte_mask(void) > > kvm_mmu_set_mmio_spte_mask((0x3ull << 62) | 0x6ull); > > } > > > > +static bool pi_desc_init(struct vcpu_vmx *vmx) > > +{ > > + unsigned int dest; > > + > > + if (irq_post_enabled == 0) > > + return true; > > + > > + /* > > + * Initialize Posted-Interrupt Descriptor > > + */ > > + > > + pi_clear_sn(&vmx->pi_desc); > > + vmx->pi_desc.nv = POSTED_INTR_VECTOR; > > + > > + /* Physical mode for Notificaiton Event */ > > + vmx->pi_desc.ndm = 0; > > + dest = cpu_physical_id(vmx->vcpu.cpu); > > + > > + if (x2apic_mode) > > + vmx->pi_desc.ndst = dest; > > + else > > + vmx->pi_desc.ndst = (dest << 8) & 0xFF00; > > + > > + return true; > > Why does this bother to return anything since it can only return true? Yes, I will make this function void. Thanks for the comments! Thanks, Feng > > > +} > > + > > + > > /* > > * Sets up the vmcs for emulated real mode. > > */ > > @@ -4439,6 +4486,11 @@ static int vmx_vcpu_setup(struct vcpu_vmx > *vmx) > > > > vmcs_write64(POSTED_INTR_NV, POSTED_INTR_VECTOR); > > vmcs_write64(POSTED_INTR_DESC_ADDR, __pa((&vmx->pi_desc))); > > + > > + if (!pi_desc_init(vmx)) { > > And therefore this cannot happen. > > > + printk(KERN_ERR "Initialize PI descriptor error!\n"); > > + return 1; > > This is the wrong error anyway, vmx_create_vcpu() returns ERR_PTR(1) > which fails the reverse IS_ERR() > > Thanks, > Alex > > > + } > > } > > > > if (ple_gap) { > > ��.n��������+%������w��{.n�����o�^n�r������&��z�ޗ�zf���h���~����������_��+v���)ߣ�
