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X-CSE-ConnectionGUID: 2N3ycHd5Qje8lygncrwJgA== X-CSE-MsgGUID: fSrqBtR2TL+ZF3+ryhODBQ== X-IronPort-AV: E=McAfee;i="6800,10657,11635"; a="68067081" X-IronPort-AV: E=Sophos;i="6.20,256,1758610800"; d="scan'208";a="68067081" Received: from fmviesa007.fm.intel.com ([10.60.135.147]) by orvoesa113.jf.intel.com with ESMTP/TLS/ECDHE-RSA-AES256-GCM-SHA384; 19 Dec 2025 10:48:41 -0800 X-CSE-ConnectionGUID: aWifCGEITieFrucIBlYJfA== X-CSE-MsgGUID: Uu3zU71YTteLVTZOO/93aA== X-ExtLoop1: 1 X-IronPort-AV: E=Sophos;i="6.21,161,1763452800"; d="scan'208";a="198513468" Received: from schen9-mobl4.amr.corp.intel.com (HELO [10.125.111.100]) ([10.125.111.100]) by fmviesa007-auth.fm.intel.com with ESMTP/TLS/ECDHE-RSA-AES256-GCM-SHA384; 19 Dec 2025 10:48:39 -0800 Message-ID: <04886fe0-a796-4265-abd9-56bfe3a0aa0c@intel.com> Date: Fri, 19 Dec 2025 10:48:38 -0800 Precedence: bulk X-Mailing-List: linux-coco@lists.linux.dev List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 User-Agent: Mozilla Thunderbird Subject: Re: [PATCH v2 2/7] KVM: x86: Extract VMXON and EFER.SVME enablement to kernel To: Sean Christopherson Cc: Thomas Gleixner , Ingo Molnar , Borislav Petkov , Dave Hansen , x86@kernel.org, Kiryl Shutsemau , Paolo Bonzini , linux-kernel@vger.kernel.org, linux-coco@lists.linux.dev, kvm@vger.kernel.org, Chao Gao , Dan Williams References: <20251206011054.494190-1-seanjc@google.com> <20251206011054.494190-3-seanjc@google.com> <90837ad5-c9a6-42da-a5a8-fcd2d870dac8@intel.com> From: Dave Hansen Content-Language: en-US Autocrypt: addr=dave.hansen@intel.com; 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charset=UTF-8 Content-Transfer-Encoding: 7bit On 12/19/25 10:35, Sean Christopherson wrote: > I haven't tested yet, but I've got this: > > struct x86_virt_ops { > int feature; > int (*enable_virtualization_cpu)(void); > int (*disable_virtualization_cpu)(void); > void (*emergency_disable_virtualization_cpu)(void); > }; > static struct x86_virt_ops virt_ops __ro_after_init; > > and then usage like: > > int x86_virt_get_ref(int feat) > { > int r; > > if (!virt_ops.feature || virt_ops.feature != feat) > return -EOPNOTSUPP; > > if (this_cpu_inc_return(virtualization_nr_users) > 1) > return 0; > > r = virt_ops.enable_virtualization_cpu(); > if (r) > WARN_ON_ONCE(this_cpu_dec_return(virtualization_nr_users)); > > return r; > } > EXPORT_SYMBOL_GPL(x86_virt_get_ref); Yeah, that's much easier to follow, and fixes the naming collision thanks!