linux-kernel - Re: [PART1 V5 07/13] KVM: x86: Detect and Initialize AVIC support

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:	Tue, 10 May 2016 11:14:47 +0200
From:	Borislav Petkov <bp@...en8.de>
To:	Suravee Suthikulpanit <Suravee.Suthikulpanit@....com>
Cc:	pbonzini@...hat.com, rkrcmar@...hat.com, joro@...tes.org,
	gleb@...nel.org, alex.williamson@...hat.com, kvm@...r.kernel.org,
	linux-kernel@...r.kernel.org, wei@...hat.com,
	sherry.hurwitz@....com
Subject: Re: [PART1 V5 07/13] KVM: x86: Detect and Initialize AVIC support

On Wed, May 04, 2016 at 02:09:46PM -0500, Suravee Suthikulpanit wrote:
> This patch introduces AVIC-related data structure, and AVIC
> initialization code.
> 
> There are three main data structures for AVIC:
>     * Virtual APIC (vAPIC) backing page (per-VCPU)
>     * Physical APIC ID table (per-VM)
>     * Logical APIC ID table (per-VM)
> 
> Currently, AVIC is disabled by default. Users can manually
> enable AVIC via kernel boot option kvm-amd.avic=1 or during
> kvm-amd module loading with parameter avic=1.
> 
> Signed-off-by: Suravee Suthikulpanit <suravee.suthikulpanit@....com>
> ---
>  arch/x86/include/asm/kvm_host.h |   4 +
>  arch/x86/include/asm/svm.h      |   3 +
>  arch/x86/kvm/svm.c              | 224 +++++++++++++++++++++++++++++++++++++++-
>  3 files changed, 230 insertions(+), 1 deletion(-)

...

> @@ -162,8 +173,19 @@ struct vcpu_svm {
>  
>  	/* cached guest cpuid flags for faster access */
>  	bool nrips_enabled	: 1;
> +
> +	struct page *avic_backing_page;
> +	u64 *avic_physical_id_cache;
>  };
>  
> +#define AVIC_LOGICAL_ID_ENTRY_GUEST_PHYSICAL_ID_MASK	(0xFF)
> +#define AVIC_LOGICAL_ID_ENTRY_VALID_MASK		(1 << 31)
> +
> +#define AVIC_PHYSICAL_ID_ENTRY_HOST_PHYSICAL_ID_MASK	(0xFFULL)
> +#define AVIC_PHYSICAL_ID_ENTRY_BACKING_PAGE_MASK	(0xFFFFFFFFFFULL << 12)
> +#define AVIC_PHYSICAL_ID_ENTRY_IS_RUNNING_MASK		(1ULL << 62)
> +#define AVIC_PHYSICAL_ID_ENTRY_VALID_MASK		(1ULL << 63)

Those defines could be shortened a little. Maybe

#define AVIC_PHYSID_HOST_PHYS_MASK
#define AVIC_PHYSID_BACKING_PG_MASK

and so on...

-- 
Regards/Gruss,
    Boris.

ECO tip #101: Trim your mails when you reply.