linux-kernel - RE: [v3 12/26] KVM: Initialize VT-d Posted-Interrupts Descriptor

lists.openwall.net		lists / announce owl-users owl-dev john-users john-dev passwdqc-users yescrypt popa3d-users / oss-security kernel-hardening musl sabotage tlsify passwords / crypt-dev xvendor / Bugtraq Full-Disclosure linux-kernel linux-netdev linux-ext4 linux-hardening linux-cve-announce PHC
Open Source and information security mailing list archives

Hash Suite: Windows password security audit tool. GUI, reports in PDF.

[<prev] [next>] [<thread-prev] [thread-next>] [day] [month] [year] [list]

Date:	Thu, 18 Dec 2014 15:19:40 +0000
From:	"Zhang, Yang Z" <yang.z.zhang@...el.com>
To:	"Wu, Feng" <feng.wu@...el.com>,
	"tglx@...utronix.de" <tglx@...utronix.de>,
	"mingo@...hat.com" <mingo@...hat.com>,
	"hpa@...or.com" <hpa@...or.com>, "x86@...nel.org" <x86@...nel.org>,
	"gleb@...nel.org" <gleb@...nel.org>,
	"pbonzini@...hat.com" <pbonzini@...hat.com>,
	"dwmw2@...radead.org" <dwmw2@...radead.org>,
	"joro@...tes.org" <joro@...tes.org>,
	"alex.williamson@...hat.com" <alex.williamson@...hat.com>,
	"jiang.liu@...ux.intel.com" <jiang.liu@...ux.intel.com>
CC:	"eric.auger@...aro.org" <eric.auger@...aro.org>,
	"linux-kernel@...r.kernel.org" <linux-kernel@...r.kernel.org>,
	"iommu@...ts.linux-foundation.org" <iommu@...ts.linux-foundation.org>,
	"kvm@...r.kernel.org" <kvm@...r.kernel.org>,
	"Wu, Feng" <feng.wu@...el.com>
Subject: RE: [v3 12/26] KVM: Initialize VT-d Posted-Interrupts Descriptor

Feng Wu wrote on 2014-12-12:
> This patch initializes the VT-d Posted-Interrupts Descriptor.
> 
> Signed-off-by: Feng Wu <feng.wu@...el.com>
> ---
>  arch/x86/kvm/vmx.c | 27 +++++++++++++++++++++++++++
>  1 file changed, 27 insertions(+)
> diff --git a/arch/x86/kvm/vmx.c b/arch/x86/kvm/vmx.c index
> 0b1383e..66ca275 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"
> @@ -4433,6 +4434,30 @@ static void ept_set_mmio_spte_mask(void)
>  	kvm_mmu_set_mmio_spte_mask((0x3ull << 62) | 0x6ull);  }
> +static void pi_desc_init(struct vcpu_vmx *vmx) {
> +	unsigned int dest;
> +
> +	if (!irq_remapping_cap(IRQ_POSTING_CAP))
> +		return;
> +
> +	/*
> +	 * Initialize Posted-Interrupt Descriptor
> +	 */
> +
> +	pi_clear_sn(&vmx->pi_desc);
> +	vmx->pi_desc.nv = POSTED_INTR_VECTOR;

Here.

> +
> +	/* Physical mode for Notificaiton Event */
> +	vmx->pi_desc.ndm = 0;

And from here..

> +	dest = cpu_physical_id(vmx->vcpu.cpu);
> +
> +	if (x2apic_enabled())
> +		vmx->pi_desc.ndst = dest;
> +	else
> +		vmx->pi_desc.ndst = (dest << 8) & 0xFF00; }
> +

..to here are useless. The right place to update PI descriptor is where vcpu got loaded not in initialization.

>  /*
>   * Sets up the vmcs for emulated real mode.
>   */
> @@ -4476,6 +4501,8 @@ 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)));
> +
> +		pi_desc_init(vmx);
>  	}
>  
>  	if (ple_gap) {


Best regards,
Yang


--
To unsubscribe from this list: send the line "unsubscribe linux-kernel" in
the body of a message to majordomo@...r.kernel.org
More majordomo info at  http://vger.kernel.org/majordomo-info.html
Please read the FAQ at  http://www.tux.org/lkml/