From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: X-Spam-Checker-Version: SpamAssassin 3.4.0 (2014-02-07) on aws-us-west-2-korg-lkml-1.web.codeaurora.org Received: from kanga.kvack.org (kanga.kvack.org [205.233.56.17]) (using TLSv1 with cipher DHE-RSA-AES256-SHA (256/256 bits)) (No client certificate requested) by smtp.lore.kernel.org (Postfix) with ESMTPS id EB171CCF9E5 for ; Mon, 27 Oct 2025 12:49:02 +0000 (UTC) Received: by kanga.kvack.org (Postfix) id 252318004E; Mon, 27 Oct 2025 08:49:02 -0400 (EDT) Received: by kanga.kvack.org (Postfix, from userid 40) id 229B68000A; Mon, 27 Oct 2025 08:49:02 -0400 (EDT) X-Delivered-To: int-list-linux-mm@kvack.org Received: by kanga.kvack.org (Postfix, from userid 63042) id 13F7D8004E; Mon, 27 Oct 2025 08:49:02 -0400 (EDT) X-Delivered-To: linux-mm@kvack.org Received: from relay.hostedemail.com (smtprelay0013.hostedemail.com [216.40.44.13]) by kanga.kvack.org (Postfix) with ESMTP id 00D6F8000A for ; Mon, 27 Oct 2025 08:49:01 -0400 (EDT) Received: from smtpin27.hostedemail.com (a10.router.float.18 [10.200.18.1]) by unirelay03.hostedemail.com (Postfix) with ESMTP id 99256B9FE7 for ; Mon, 27 Oct 2025 12:49:01 +0000 (UTC) X-FDA: 84043874082.27.CCD25DA Received: from mail-pg1-f201.google.com (mail-pg1-f201.google.com [209.85.215.201]) by imf28.hostedemail.com (Postfix) with ESMTP id D2245C0003 for ; Mon, 27 Oct 2025 12:48:59 +0000 (UTC) Authentication-Results: imf28.hostedemail.com; dkim=pass header.d=google.com header.s=20230601 header.b=N4t0OS5M; spf=pass (imf28.hostedemail.com: domain of 3Omr_aAsKCFs35D7KE7RMG99HH9E7.5HFEBGNQ-FFDO35D.HK9@flex--ackerleytng.bounces.google.com designates 209.85.215.201 as permitted sender) smtp.mailfrom=3Omr_aAsKCFs35D7KE7RMG99HH9E7.5HFEBGNQ-FFDO35D.HK9@flex--ackerleytng.bounces.google.com; dmarc=pass (policy=reject) header.from=google.com ARC-Message-Signature: i=1; a=rsa-sha256; c=relaxed/relaxed; d=hostedemail.com; s=arc-20220608; t=1761569339; h=from:from:sender:reply-to:subject:subject:date:date: message-id:message-id:to:to:cc:cc:mime-version:mime-version: content-type:content-type:content-transfer-encoding: in-reply-to:in-reply-to:references:references:dkim-signature; bh=TpsH9gx/luUFZveFm6voMll1yjdVEPjIbyyyxybZ4HQ=; b=apbQAHqQUxspbdYKQ/YEuI2gslry6Yjsb8ZtWIHv90vbOdFIgXuvKfae0oFfjf8cTABGp6 Rq8IujmI3d8YMbRl6f1/TdpM9nR7IU9rj0rlBBPY+9SlQtgElxVj+BzoO3XGcj4uziKEI4 JLJGOpsXS2NjW00N57KXftWQE5qKz9E= ARC-Authentication-Results: i=1; imf28.hostedemail.com; dkim=pass header.d=google.com header.s=20230601 header.b=N4t0OS5M; spf=pass (imf28.hostedemail.com: domain of 3Omr_aAsKCFs35D7KE7RMG99HH9E7.5HFEBGNQ-FFDO35D.HK9@flex--ackerleytng.bounces.google.com designates 209.85.215.201 as permitted sender) smtp.mailfrom=3Omr_aAsKCFs35D7KE7RMG99HH9E7.5HFEBGNQ-FFDO35D.HK9@flex--ackerleytng.bounces.google.com; dmarc=pass (policy=reject) header.from=google.com ARC-Seal: i=1; s=arc-20220608; d=hostedemail.com; t=1761569339; a=rsa-sha256; cv=none; b=gyZGijXFX9YghUzTXeDSEO+QQfsAFk/mpLJpHpCvmIBy4JIznBmvLSKeDm9SbnkTYiXBbE ETOABdNMRGpInPUFbb3RnBQsoeTevzXkM9UgyZGiz4Vt4tEUK7CwQIaSVQUYH/e+SPYxtV UGDKfGx1yZA9VF468GVq3V03ZPR0hxs= Received: by mail-pg1-f201.google.com with SMTP id 41be03b00d2f7-b6cf1b799dcso3278727a12.2 for ; Mon, 27 Oct 2025 05:48:59 -0700 (PDT) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=google.com; s=20230601; t=1761569338; x=1762174138; darn=kvack.org; h=cc:to:from:subject:message-id:references:mime-version:in-reply-to :date:from:to:cc:subject:date:message-id:reply-to; bh=TpsH9gx/luUFZveFm6voMll1yjdVEPjIbyyyxybZ4HQ=; b=N4t0OS5McZM7QWcK/z+0c/H/pJLvJmnBGAdDp9l7i8/pSy4IL4lB2+e3kHzG0w54Ei 2txBPTy0clivsOyZsKLoCUauj6q8ciJf1ib9uSvGcc9yMs+EuotOhHgId0Eq0Bp29tDS 9RW/ghkelCq7J5hx/ASpaIgRqVBEo67Lj38vAX5VdCPFqZBGR/Bah9fk0GWPHh1AoYuT xYsIW3AqaX2Xe3645hTHeqko8e94JrE3Zh7N8UHhONtuvp5mbtBJwksVmAsbGpj3MozY NNSllvpzWIr8REJGXkH2CM1IMenK7PrTbiNoWdQgddmrswal5bjqMakytZtIlVjafJpP OAzw== X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20230601; t=1761569338; x=1762174138; h=cc:to:from:subject:message-id:references:mime-version:in-reply-to :date:x-gm-message-state:from:to:cc:subject:date:message-id:reply-to; bh=TpsH9gx/luUFZveFm6voMll1yjdVEPjIbyyyxybZ4HQ=; b=tkumvs7BJGqjr7hSGucKZdq3uQznMJacVSGf351ULXpPYIHMGxiEtO6FAQqfnYP5Sk QJvnhMToGcpgraGmU5n/Mz17gjPkmkRAttnrwr2biVqlfWE2dzkFfqWUf7dAOIsWoQqR KsQY69QBxus9a8yVpM8OgMPRGke9ajLXBiB2ImbM/nv3wIDljrXqpS8V4EQ/W5ta6A48 kHCUYWaR7bD2igxa52sSdiHI7kQEcqWZDCghcUjLQjQQIQKIY2+nsjMyek9ylT7lFbx4 UMziwux9zrizcjbILip8TjdyvY4aOoTP+aUC5mW0KbCT9d3E9aSkWO+Wzr/01NUUTNjt ISAw== X-Forwarded-Encrypted: i=1; AJvYcCX76gbIIEo2lAYWNE9n26pdE4AVXDO9QxWBzMA6+WHdfS9VDsumjMvUB5f/rWE2MvaGXbBJuGauyA==@kvack.org X-Gm-Message-State: AOJu0YzBGdy3KQihVjSJcDb/G9CqL2p4TrT+ffpj3i8SO5NxEyWfquh4 5qMHzwGv8uZXV6RQtQEcCk8pRldwDuK/5ljd5mLTXF4Qql8L2555j8HYVbovGQAhrpuKhubzQGH Thn6yau6xA9Zv8FLBVQleNzy8/Q== X-Google-Smtp-Source: AGHT+IE8aJKICvS5xOA+BTAY6bjRh41q0VtmGZijtJh7qHPsEmdIFH7jOAvP+FEHmW/GVGRbcG4XOU1+vDg6R+rrXQ== X-Received: from plbmg14.prod.google.com ([2002:a17:903:348e:b0:268:e12a:2266]) (user=ackerleytng job=prod-delivery.src-stubby-dispatcher) by 2002:a17:902:d60d:b0:270:e595:a440 with SMTP id d9443c01a7336-290c9cd4b48mr418021645ad.25.1761569338212; Mon, 27 Oct 2025 05:48:58 -0700 (PDT) Date: Mon, 27 Oct 2025 05:48:56 -0700 In-Reply-To: Mime-Version: 1.0 References: <8ee16fbf254115b0fd72cc2b5c06d2ccef66eca9.1760731772.git.ackerleytng@google.com> <2457cb3b-5dde-4ca1-b75d-174b5daee28a@arm.com> Message-ID: Subject: Re: [RFC PATCH v1 07/37] KVM: Introduce KVM_SET_MEMORY_ATTRIBUTES2 From: Ackerley Tng To: Sean Christopherson Cc: Steven Price , cgroups@vger.kernel.org, kvm@vger.kernel.org, linux-doc@vger.kernel.org, linux-fsdevel@vger.kernel.org, linux-kernel@vger.kernel.org, linux-kselftest@vger.kernel.org, linux-mm@kvack.org, linux-trace-kernel@vger.kernel.org, x86@kernel.org, akpm@linux-foundation.org, binbin.wu@linux.intel.com, bp@alien8.de, brauner@kernel.org, chao.p.peng@intel.com, chenhuacai@kernel.org, corbet@lwn.net, dave.hansen@intel.com, dave.hansen@linux.intel.com, david@redhat.com, dmatlack@google.com, erdemaktas@google.com, fan.du@intel.com, fvdl@google.com, haibo1.xu@intel.com, hannes@cmpxchg.org, hch@infradead.org, hpa@zytor.com, hughd@google.com, ira.weiny@intel.com, isaku.yamahata@intel.com, jack@suse.cz, james.morse@arm.com, jarkko@kernel.org, jgg@ziepe.ca, jgowans@amazon.com, jhubbard@nvidia.com, jthoughton@google.com, jun.miao@intel.com, kai.huang@intel.com, keirf@google.com, kent.overstreet@linux.dev, liam.merwick@oracle.com, maciej.wieczor-retman@intel.com, mail@maciej.szmigiero.name, maobibo@loongson.cn, mathieu.desnoyers@efficios.com, maz@kernel.org, mhiramat@kernel.org, mhocko@kernel.org, mic@digikod.net, michael.roth@amd.com, mingo@redhat.com, mlevitsk@redhat.com, mpe@ellerman.id.au, muchun.song@linux.dev, nikunj@amd.com, nsaenz@amazon.es, oliver.upton@linux.dev, palmer@dabbelt.com, pankaj.gupta@amd.com, paul.walmsley@sifive.com, pbonzini@redhat.com, peterx@redhat.com, pgonda@google.com, prsampat@amd.com, pvorel@suse.cz, qperret@google.com, richard.weiyang@gmail.com, rick.p.edgecombe@intel.com, rientjes@google.com, rostedt@goodmis.org, roypat@amazon.co.uk, rppt@kernel.org, shakeel.butt@linux.dev, shuah@kernel.org, suzuki.poulose@arm.com, tabba@google.com, tglx@linutronix.de, thomas.lendacky@amd.com, vannapurve@google.com, vbabka@suse.cz, viro@zeniv.linux.org.uk, vkuznets@redhat.com, will@kernel.org, willy@infradead.org, wyihan@google.com, xiaoyao.li@intel.com, yan.y.zhao@intel.com, yilun.xu@intel.com, yuzenghui@huawei.com Content-Type: text/plain; charset="UTF-8" X-Stat-Signature: fk99xg5emwe5g3xhk545zyirddd7kbgz X-Rspam-User: X-Rspamd-Server: rspam07 X-Rspamd-Queue-Id: D2245C0003 X-HE-Tag: 1761569339-336666 X-HE-Meta: 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 BwQD+AQH 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 X-Bogosity: Ham, tests=bogofilter, spamicity=0.000000, version=1.2.4 Sender: owner-linux-mm@kvack.org Precedence: bulk X-Loop: owner-majordomo@kvack.org List-ID: List-Subscribe: List-Unsubscribe: Sean Christopherson writes: > On Fri, Oct 24, 2025, Ackerley Tng wrote: >> Sean Christopherson writes: >> > @@ -486,6 +488,7 @@ struct kvm_vm *__vm_create(struct vm_shape shape, uint32_t nr_runnable_vcpus, >> > } >> > guest_rng = new_guest_random_state(guest_random_seed); >> > sync_global_to_guest(vm, guest_rng); >> > + sync_global_to_guest(vm, kvm_has_gmem_attributes); >> >> I ported this [1] except for syncing this value to the guest, because I >> think the guest shouldn't need to know this information, > > KVM selftests are about practically and testing, what information should or > shouldn't be available to a test from e.g. a safety perspective is completely > irrelevant. In fact, one of the biggest advantages of selftests over KUT is > that the guest side can know _exactly_ what's going on in the host. > > See the usage in 1850e3da4b03 ("KVM: selftests: Update private_mem_conversions_test > to mmap() guest_memfd") from: > > https://github.com/sean-jc/linux.git x86/gmem_inplace > >> the host should decide what to do. I think, if the guests really need to know >> this, the test itself can do the syncing. > > Why force tests to do extra work, and potentially introduce subtle bugs due to > state being stale? Adding it back. Thanks! This variable should be sync-able for TDX selftests as well since the value should be synced before the TD image is loaded.