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]) by smtp.lore.kernel.org (Postfix) with ESMTP id E88FAC2D0CD for ; Wed, 21 May 2025 10:13:18 +0000 (UTC) Received: by kanga.kvack.org (Postfix) id 82F906B008C; Wed, 21 May 2025 06:13:18 -0400 (EDT) Received: by kanga.kvack.org (Postfix, from userid 40) id 805EC6B0092; Wed, 21 May 2025 06:13:18 -0400 (EDT) X-Delivered-To: int-list-linux-mm@kvack.org Received: by kanga.kvack.org (Postfix, from userid 63042) id 743A16B0093; Wed, 21 May 2025 06:13:18 -0400 (EDT) X-Delivered-To: linux-mm@kvack.org Received: from relay.hostedemail.com (smtprelay0010.hostedemail.com [216.40.44.10]) by kanga.kvack.org (Postfix) with ESMTP id 55E936B008C for ; Wed, 21 May 2025 06:13:18 -0400 (EDT) Received: from smtpin18.hostedemail.com (a10.router.float.18 [10.200.18.1]) by unirelay04.hostedemail.com (Postfix) with ESMTP id 021011A0EB6 for ; Wed, 21 May 2025 10:13:17 +0000 (UTC) X-FDA: 83466502476.18.3FFEE52 Received: from mail-qt1-f176.google.com (mail-qt1-f176.google.com [209.85.160.176]) by imf01.hostedemail.com (Postfix) with ESMTP id 368B34000A for ; Wed, 21 May 2025 10:13:16 +0000 (UTC) Authentication-Results: imf01.hostedemail.com; dkim=pass header.d=google.com header.s=20230601 header.b=RZ5IN8KP; spf=pass (imf01.hostedemail.com: domain of tabba@google.com designates 209.85.160.176 as permitted sender) smtp.mailfrom=tabba@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=1747822396; 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=d5QSndPkKAQ5vtrh+loQIW/5wevzzB6SrBoHRCKbDvk=; b=L3qsRsCBd0XPwk+3eiTYdhSHCnHC5a1rDKNz9GILsnWqM9fNepHPVLC9HqjbJKS3BN6SsI nGH58ZAERFSkpcgAawCJLuZPXCXST0AT01yBtP0IhFGcXauX29nlDGtkVopKkHb2JqKgq2 e6WDCu3pGtLVBwMWl8sgKBYlD/eeSKo= ARC-Seal: i=1; s=arc-20220608; d=hostedemail.com; t=1747822396; a=rsa-sha256; cv=none; b=Pxe4e5bRo0do3m2MwEcHOnfXK42y762bmVFZoURA6nRZ5E8PsnxVQeiDI6GiqU5t5bPu7T apKaoz1haXUXRY2UnhZRZb7Ud6r0whmmUqIKT0QpjdYvXhRwDdF08Ap2tBnTKSV+Uj3mi6 SjUEQpl1l8NzCnPtNh2pCrG4H57Z6Cw= ARC-Authentication-Results: i=1; imf01.hostedemail.com; dkim=pass header.d=google.com header.s=20230601 header.b=RZ5IN8KP; spf=pass (imf01.hostedemail.com: domain of tabba@google.com designates 209.85.160.176 as permitted sender) smtp.mailfrom=tabba@google.com; dmarc=pass (policy=reject) header.from=google.com Received: by mail-qt1-f176.google.com with SMTP id d75a77b69052e-47e9fea29easo1628241cf.1 for ; Wed, 21 May 2025 03:13:15 -0700 (PDT) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=google.com; s=20230601; t=1747822395; x=1748427195; darn=kvack.org; h=cc:to:subject:message-id:date:from:in-reply-to:references :mime-version:from:to:cc:subject:date:message-id:reply-to; bh=d5QSndPkKAQ5vtrh+loQIW/5wevzzB6SrBoHRCKbDvk=; b=RZ5IN8KP1Lakeda8YcsfJxSKUYAZG5wOHhPb9rWZMP8PtzfK/0zQXfDhgfx8c8uxQK ZMptPBYKMGtEjzTYrRB4900B19UAhzae4mzNhgDdLDA1Bx51WM7fOpDuxmW5p+an8b/p du6cVdFbA99xb/iz8mIqbmgkHpw1a707xgvJjbMcjWsXqQX454THBHLMxuPWkHgbVzuV VhML8NactikR6jVKcIWWTVl7ksk/1u+7mumIAC19xRWvXC000I8toMR6FKDMSSBnhQTj ybN+oc5wwJEOhAuKzgy3X6CmA5jYXgSxshUv3Lb1hwd+Dr1GaoYtx+rG5KHJlPmgm8uB eARQ== X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20230601; t=1747822395; x=1748427195; h=cc:to:subject:message-id:date:from:in-reply-to:references :mime-version:x-gm-message-state:from:to:cc:subject:date:message-id :reply-to; bh=d5QSndPkKAQ5vtrh+loQIW/5wevzzB6SrBoHRCKbDvk=; b=a2AK+J/kJEWpzKh/UTGDnpuaG9JHer1NFXV8FxCxKMk2jrxinupg+D3tAQGWRrP0to vKHWTArpqd2USDkDMFHmh/94xNGg5YvlM9U8Xm+zPBtM8nzi8gVZ6ASEwNTT0OqR8j+x 4RH30TUsaAo4ZDXSt/cf4gPFtC7Ex7J4QBQXdMbbINtDuT/gkXBxKrGANyPRTDSx7sZ+ hLYLOfNuHLr9vMQERwyOxeQaztfkdybZBIqtkVDvj7523QbV+fgrXo+pg0k+VpoPi8km cDMI0RX1QPa7RX9l1+GHQzzJpD0gwB4Yh5mjftGr0f84XkLeGuWkFpArtRAo+4gHNI/m eBNA== X-Forwarded-Encrypted: i=1; AJvYcCUl7vlN8IHD3zRxFiMKBuuV9ghRJq7tlCA2GTb1PUqQSPnXsoVHRKtA3c9iP+nH6vOPlzhxBNeu7Q==@kvack.org X-Gm-Message-State: AOJu0YzkT4p+eNo9Q/ip6frgrCLQk+48I5eUSZnf7Vi3JkmLcrNko9rf FZ6+R2OvmE/UfnDMvPKCrGErE57KWx0dyYJCd0OeJBMElIbgz5HMrljKEdogD7Av2gUHYcAXG1C 5VrzJGXED7JNf1VH2sqrci4O0OtpRZ0ZUZ00G0dlW X-Gm-Gg: ASbGnct2hptey6QBYYYB4G2OiLznPpacj+3aBqy0C001alqPlZ180Kwz35tU8uWXD3a zs+VXkWNeRjRgNyQkuBtp+68JLpcTtgJYzsDeVRw03T3GGhNvfgn+lDoFpti04RxST1y3MqG8wI xoA2OuNFFoHflmXdgzjo15S+M0I6WfzZmEE3tUPmMXJJWTq+re4JBEY0puT0als2evaT/MIxFD X-Google-Smtp-Source: AGHT+IFBSwGTdaQw/b8ps6ywr/tb178e/gz6GEZe1xfE1CXyjCsW9YbGLGngSw4suyfsuW4AGbCdMTzW2uSsF1TF0qk= X-Received: by 2002:a05:622a:1826:b0:494:af4b:59fd with SMTP id d75a77b69052e-49595d52c6emr16768151cf.18.1747822394826; Wed, 21 May 2025 03:13:14 -0700 (PDT) MIME-Version: 1.0 References: <20250513163438.3942405-1-tabba@google.com> <20250513163438.3942405-15-tabba@google.com> <2084504e-2a11-404a-bbe8-930384106f53@redhat.com> In-Reply-To: <2084504e-2a11-404a-bbe8-930384106f53@redhat.com> From: Fuad Tabba Date: Wed, 21 May 2025 11:12:37 +0100 X-Gm-Features: AX0GCFs6mm4R5LsozR4hLz8YIdTF39WQ3BoVlZqAx_u_jdRTh6jdrQkuKqVFCts Message-ID: Subject: Re: [PATCH v9 14/17] KVM: arm64: Enable mapping guest_memfd in arm64 To: David Hildenbrand Cc: kvm@vger.kernel.org, linux-arm-msm@vger.kernel.org, linux-mm@kvack.org, pbonzini@redhat.com, chenhuacai@kernel.org, mpe@ellerman.id.au, anup@brainfault.org, paul.walmsley@sifive.com, palmer@dabbelt.com, aou@eecs.berkeley.edu, seanjc@google.com, viro@zeniv.linux.org.uk, brauner@kernel.org, willy@infradead.org, akpm@linux-foundation.org, xiaoyao.li@intel.com, yilun.xu@intel.com, chao.p.peng@linux.intel.com, jarkko@kernel.org, amoorthy@google.com, dmatlack@google.com, isaku.yamahata@intel.com, mic@digikod.net, vbabka@suse.cz, vannapurve@google.com, ackerleytng@google.com, mail@maciej.szmigiero.name, michael.roth@amd.com, wei.w.wang@intel.com, liam.merwick@oracle.com, isaku.yamahata@gmail.com, kirill.shutemov@linux.intel.com, suzuki.poulose@arm.com, steven.price@arm.com, quic_eberman@quicinc.com, quic_mnalajal@quicinc.com, quic_tsoni@quicinc.com, quic_svaddagi@quicinc.com, quic_cvanscha@quicinc.com, quic_pderrin@quicinc.com, quic_pheragu@quicinc.com, catalin.marinas@arm.com, james.morse@arm.com, yuzenghui@huawei.com, oliver.upton@linux.dev, maz@kernel.org, will@kernel.org, qperret@google.com, keirf@google.com, roypat@amazon.co.uk, shuah@kernel.org, hch@infradead.org, jgg@nvidia.com, rientjes@google.com, jhubbard@nvidia.com, fvdl@google.com, hughd@google.com, jthoughton@google.com, peterx@redhat.com, pankaj.gupta@amd.com, ira.weiny@intel.com Content-Type: text/plain; charset="UTF-8" X-Stat-Signature: heu76tr3yqzkugqdfxie81nuimw76ig8 X-Rspamd-Queue-Id: 368B34000A X-Rspam-User: X-Rspamd-Server: rspam02 X-HE-Tag: 1747822396-890323 X-HE-Meta: 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 Rk4CTtIo MOgCX/TfA8ymRjKXWpBn9hCA8v4vOHuL7RHKXx45dx7OMAM4HZpb2SOdXWP5hL6qRde0BDHyLOBre8IAWH+zeid3trZKGE0++CUA12LvsBqOFmYyYpfPNwZGgzV5wpeOj9AWhC2mdA9h9gl+OqYYTPgm7BO68vjjI3DL4vIIkaIpXOOXiLXRzwLvGz5Ezapib88nuGUxeOHEjV3AH8AtXTgtsD1CloGOX8WZnsyFsSU9XInvmBGDpilqpXfLc1/CYxQ+DiK4UnGdJuc9NmpgUj9DIKtIyMqmJn1zWUk+nX6VM6VlRCzK5YPpNwMoBqfflrFE/uDCs31jjqjfW0CfV6wU0WoNx+jgnSYsVr54GX5GWg7iK2i5EDD8DFQBe0xKLT5h/h09CJA3lYVVP9W4SbZbWWWHo5A3TRrbc 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: Hi David, On Wed, 21 May 2025 at 09:05, David Hildenbrand wrote: > > On 13.05.25 18:34, Fuad Tabba wrote: > > Enable mapping guest_memfd in arm64. For now, it applies to all > > VMs in arm64 that use guest_memfd. In the future, new VM types > > can restrict this via kvm_arch_gmem_supports_shared_mem(). > > > > Signed-off-by: Fuad Tabba > > --- > > arch/arm64/include/asm/kvm_host.h | 10 ++++++++++ > > arch/arm64/kvm/Kconfig | 1 + > > 2 files changed, 11 insertions(+) > > > > diff --git a/arch/arm64/include/asm/kvm_host.h b/arch/arm64/include/asm/kvm_host.h > > index 08ba91e6fb03..2514779f5131 100644 > > --- a/arch/arm64/include/asm/kvm_host.h > > +++ b/arch/arm64/include/asm/kvm_host.h > > @@ -1593,4 +1593,14 @@ static inline bool kvm_arch_has_irq_bypass(void) > > return true; > > } > > > > +static inline bool kvm_arch_supports_gmem(struct kvm *kvm) > > +{ > > + return IS_ENABLED(CONFIG_KVM_GMEM); > > +} > > + > > +static inline bool kvm_arch_vm_supports_gmem_shared_mem(struct kvm *kvm) > > +{ > > + return IS_ENABLED(CONFIG_KVM_GMEM_SHARED_MEM); > > +} > > + > > #endif /* __ARM64_KVM_HOST_H__ */ > > diff --git a/arch/arm64/kvm/Kconfig b/arch/arm64/kvm/Kconfig > > index 096e45acadb2..8c1e1964b46a 100644 > > --- a/arch/arm64/kvm/Kconfig > > +++ b/arch/arm64/kvm/Kconfig > > @@ -38,6 +38,7 @@ menuconfig KVM > > select HAVE_KVM_VCPU_RUN_PID_CHANGE > > select SCHED_INFO > > select GUEST_PERF_EVENTS if PERF_EVENTS > > + select KVM_GMEM_SHARED_MEM > > help > > Support hosting virtualized guest machines. > > > > Do we have to reject somewhere if we are given a guest_memfd that was > *not* created using the SHARED flag? Or will existing checks already > reject that? We don't reject, but I don't think we need to. A user can create a guest_memfd that's private in arm64, it would just be useless. Cheers, /fuad > -- > Cheers, > > David / dhildenb >