From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from mgamail.intel.com (mgamail.intel.com [192.198.163.16]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by smtp.subspace.kernel.org (Postfix) with ESMTPS id 6AE053F44C1; Wed, 1 Jul 2026 09:20:27 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.client-ip=192.198.163.16 ARC-Seal:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1782897629; cv=none; b=uLHcOYoe8syZzdkUQ5CyzDomQW9fQ2ZLxfErWoukUjV0aj3OtjOsZvdnueqkg/Rz200oU5s/D9WAPnAxBkSGI/OEt7mnCxn2PWrLhM4/EhohAvY4bEw0NqRcq1XaAp4EsYcV0nqXgQMu5fxRRqUWCvG/Kv5A6JE5oKCuFi1HpJc= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1782897629; c=relaxed/simple; bh=7J8U0aOHIOgQWuEsjj2TtWJ9iF88n4wrQKbJKxMJsMU=; h=Message-ID:Date:MIME-Version:Subject:To:Cc:References:From: In-Reply-To:Content-Type; b=ldxrJTCrg3x79lqPCjdegEfZXSYvK5Rbk/vM1qgIM4w/Sl6/nw2PzZH0cLu9Q5XoQ8izDCcpP9MJY2JVhnPMJMswFfd24p0S+atKunJ5ytcRCq3dZXINXvBqTCxjRtXsql4c2aUnm/oTkfMVXdfVc1KH1VOEhwqedG5bWPd5Iyg= ARC-Authentication-Results:i=1; smtp.subspace.kernel.org; dmarc=pass (p=none dis=none) header.from=intel.com; spf=pass smtp.mailfrom=intel.com; dkim=pass (2048-bit key) header.d=intel.com header.i=@intel.com header.b=XK4MnQt0; arc=none smtp.client-ip=192.198.163.16 Authentication-Results: smtp.subspace.kernel.org; dmarc=pass (p=none dis=none) header.from=intel.com Authentication-Results: smtp.subspace.kernel.org; spf=pass smtp.mailfrom=intel.com Authentication-Results: smtp.subspace.kernel.org; dkim=pass (2048-bit key) header.d=intel.com header.i=@intel.com header.b="XK4MnQt0" DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=intel.com; i=@intel.com; q=dns/txt; s=Intel; t=1782897627; x=1814433627; h=message-id:date:mime-version:subject:to:cc:references: from:in-reply-to:content-transfer-encoding; bh=7J8U0aOHIOgQWuEsjj2TtWJ9iF88n4wrQKbJKxMJsMU=; b=XK4MnQt0hZ8LWZuZ6RjBzlNeIcRwghVNNP1FEkE24t80Sbq9Sv/YOBJt 2ISsnY5b5dq1uD+T8KszohM8SMxjOCZc85oeJIUkrnVM4L45Y1qvTW0CV AAZoDcXNqLicQIvX400s1twrImbknyYTlr/VZAjJJO2KHmhzmlmlzZ+6t PP5SkYR1PE8He9sVnadRvuwjYKvwkh62gpO935v95+GXD0uxd/z0lAcn/ gIckyqH59sU0Cg0DqIVJFPCH3VCTOSc+u87BQ5db5KOBKtqDHdGA50vUy 9q+Krp6rErXm/6JYARhwJ238IjfovKp4PaFzTHGdW1Pznwqbk68Z0+B2r Q==; X-CSE-ConnectionGUID: DS4iwU16RXqNnhiehz54jA== X-CSE-MsgGUID: 8UIGvcxyS56IUW484EstBQ== X-IronPort-AV: E=McAfee;i="6800,10657,11833"; a="71148513" X-IronPort-AV: E=Sophos;i="6.24,235,1774335600"; d="scan'208";a="71148513" Received: from orviesa007.jf.intel.com ([10.64.159.147]) by fmvoesa110.fm.intel.com with ESMTP/TLS/ECDHE-RSA-AES256-GCM-SHA384; 01 Jul 2026 02:20:26 -0700 X-CSE-ConnectionGUID: GCoFRbeXS+CWkw/DTSBMHg== X-CSE-MsgGUID: g0z9xiZWQNWS5ThC6q4GpA== X-ExtLoop1: 1 X-IronPort-AV: E=Sophos;i="6.24,235,1774335600"; d="scan'208";a="252647190" Received: from unknown (HELO [10.239.158.49]) ([10.239.158.49]) by orviesa007-auth.jf.intel.com with ESMTP/TLS/ECDHE-RSA-AES256-GCM-SHA384; 01 Jul 2026 02:19:59 -0700 Message-ID: <739e6834-40b3-405b-ada4-d31c38d8416a@intel.com> Date: Wed, 1 Jul 2026 17:19:54 +0800 Precedence: bulk X-Mailing-List: linux-trace-kernel@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 User-Agent: Mozilla Thunderbird Subject: Re: [PATCH v8 06/46] KVM: Enumerate support for PRIVATE memory iff kvm_arch_has_private_mem is defined To: ackerleytng@google.com, aik@amd.com, andrew.jones@linux.dev, binbin.wu@linux.intel.com, brauner@kernel.org, chao.p.peng@linux.intel.com, david@kernel.org, jmattson@google.com, jthoughton@google.com, michael.roth@amd.com, oupton@kernel.org, pankaj.gupta@amd.com, qperret@google.com, rick.p.edgecombe@intel.com, rientjes@google.com, shivankg@amd.com, steven.price@arm.com, tabba@google.com, willy@infradead.org, wyihan@google.com, yan.y.zhao@intel.com, forkloop@google.com, pratyush@kernel.org, suzuki.poulose@arm.com, aneesh.kumar@kernel.org, liam@infradead.org, Paolo Bonzini , Sean Christopherson , Thomas Gleixner , Ingo Molnar , Borislav Petkov , Dave Hansen , x86@kernel.org, "H. Peter Anvin" , Steven Rostedt , Masami Hiramatsu , Mathieu Desnoyers , Jonathan Corbet , Shuah Khan , Shuah Khan , Vishal Annapurve , Andrew Morton , Chris Li , Kairui Song , Kemeng Shi , Nhat Pham , Barry Song , Axel Rasmussen , Yuanchu Xie , Wei Xu , Youngjun Park , Qi Zheng , Shakeel Butt , Kiryl Shutsemau , Baoquan He , Jason Gunthorpe , Vlastimil Babka Cc: kvm@vger.kernel.org, linux-kernel@vger.kernel.org, linux-trace-kernel@vger.kernel.org, linux-doc@vger.kernel.org, linux-kselftest@vger.kernel.org, linux-mm@kvack.org, linux-coco@lists.linux.dev References: <20260618-gmem-inplace-conversion-v8-0-9d2959357853@google.com> <20260618-gmem-inplace-conversion-v8-6-9d2959357853@google.com> Content-Language: en-US From: Xiaoyao Li In-Reply-To: <20260618-gmem-inplace-conversion-v8-6-9d2959357853@google.com> Content-Type: text/plain; charset=UTF-8; format=flowed Content-Transfer-Encoding: 7bit On 6/19/2026 8:31 AM, Ackerley Tng via B4 Relay wrote: > From: Ackerley Tng > > Explicitly guard reporting support for KVM_MEMORY_ATTRIBUTE_PRIVATE based > on kvm_arch_has_private_mem being #defined in anticipation of decoupling > kvm_supported_mem_attributes() from CONFIG_KVM_VM_MEMORY_ATTRIBUTES. Well, after this series, kvm_supported_mem_attributes() is renamed to kvm_supported_vm_mem_attributes(), and it's still under CONFIG_KVM_VM_MEMORY_ATTRIBUTES. > guest_memfd support for memory attributes will be unconditional to avoid > yet more macros (all architectures that support guest_memfd are expected to > use per-gmem attributes at some point), at which point enumerating support > KVM_MEMORY_ATTRIBUTE_PRIVATE based solely on memory attributes being > supported _somewhere_ would result in KVM over-reporting support on arm64. I don't understand it. This patch only changes the behavior of kvm_supported_mem_attributes(), the usage of which is guarded by CONFIG_KVM_VM_MEMORY_ATTRIBUTES. This is config is only visible to x86 due to patch 03. How does it affect arm64? > Signed-off-by: Sean Christopherson > Reviewed-by: Fuad Tabba > Signed-off-by: Ackerley Tng > --- > virt/kvm/kvm_main.c | 2 ++ > 1 file changed, 2 insertions(+) > > diff --git a/virt/kvm/kvm_main.c b/virt/kvm/kvm_main.c > index 1ccc4895a4c26..7b989b659cf82 100644 > --- a/virt/kvm/kvm_main.c > +++ b/virt/kvm/kvm_main.c > @@ -2421,8 +2421,10 @@ static int kvm_vm_ioctl_clear_dirty_log(struct kvm *kvm, > #ifdef CONFIG_KVM_VM_MEMORY_ATTRIBUTES > static u64 kvm_supported_mem_attributes(struct kvm *kvm) > { > +#ifdef kvm_arch_has_private_mem > if (!kvm || kvm_arch_has_private_mem(kvm)) > return KVM_MEMORY_ATTRIBUTE_PRIVATE; > +#endif > > return 0; > } >