From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from smtp.kernel.org (aws-us-west-2-korg-mail-1.web.codeaurora.org [10.30.226.201]) (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 6DA3B25F99F; Wed, 29 Jul 2026 00:35:08 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.client-ip=10.30.226.201 ARC-Seal:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1785285308; cv=none; b=cl+XUalnbNX4ye66wes2MJjZgpurfVldImiS3NrnZ7AwS4mlvMl6jmPE+WiGENnim/UZ1EjuxRps/xiTVVCHm2nNqlxrXY0lpZeXuAtNfjX+u8YDxBigUUFiCNCInvcKdrsWCDaJID4akj4q/bbv6BqRRr4aInaUEnNoQvhj9sQ= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1785285308; c=relaxed/simple; bh=Rr+fXnWaxGybs+AWEondw/0B6Nh+LgNpDLrKdIyfAHw=; h=From:Date:Subject:MIME-Version:Content-Type:Message-Id:References: In-Reply-To:To:Cc; b=Vs1WjnPRGxfzPUfJl/Xp0srySTMn+SMEzG2a/S6FYiKTq5iRU7QB8rCUhrAw5onJcCWmukOtWsBx1oJ2R2VEqL0Hu5uyB2eLvhO0NmLNRdHQgD1nCMA406VR/bf6o/Vhz7N76u09zugig0JUuX2WsicnUJqpVsD/MA707A1wYeI= ARC-Authentication-Results:i=1; smtp.subspace.kernel.org; dkim=pass (2048-bit key) header.d=kernel.org header.i=@kernel.org header.b=gKKpH51S; arc=none smtp.client-ip=10.30.226.201 Authentication-Results: smtp.subspace.kernel.org; dkim=pass (2048-bit key) header.d=kernel.org header.i=@kernel.org header.b="gKKpH51S" Received: by smtp.kernel.org (Postfix) with ESMTPS id 2CE08C4AF1D; Wed, 29 Jul 2026 00:35:08 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=k20201202; t=1785285308; bh=Rr+fXnWaxGybs+AWEondw/0B6Nh+LgNpDLrKdIyfAHw=; h=From:Date:Subject:References:In-Reply-To:To:Cc:Reply-To:From; b=gKKpH51SjITRNdhUTuh3G3X0yqQwxAESgR7Ikwou3Nq7PBNWDsKLPHed1YxLUdXWi P5MsMkyClfkKfWFTpvxx+LewIEDMs5dwu+d421k1yGpJzE2tInf/gH79bQaZ3y1aFj uR5fLuKOB6Y7UOlTY20dZFfVnhrmHxPs6+u+QnNoeSBByz3Pkmdgg+21Bq1guMDs04 JKM4OAeVpxEgd14B3Xtw/K1ivPTstInsfubXTjMicqPx8vzQYaG/sPVaL4dou1twut 90gD1Dwl01f+Xo1YQL0YCu8K7Wma/xDg1n9m24N80dbpjvyD860nuwZPtzWB69cfhI E7j05/xWvUUcw== Received: from aws-us-west-2-korg-lkml-1.web.codeaurora.org (localhost.localdomain [127.0.0.1]) by smtp.lore.kernel.org (Postfix) with ESMTP id 059CDC53219; Wed, 29 Jul 2026 00:35:08 +0000 (UTC) From: Ackerley Tng via B4 Relay Date: Tue, 28 Jul 2026 17:35:04 -0700 Subject: [PATCH v9 05/41] KVM: Provide generic interface for checking memory private/shared status Precedence: bulk X-Mailing-List: linux-trace-kernel@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 Content-Type: text/plain; charset="utf-8" Content-Transfer-Encoding: 7bit Message-Id: <20260728-gmem-inplace-conversion-v9-5-35f9aec2aed2@google.com> References: <20260728-gmem-inplace-conversion-v9-0-35f9aec2aed2@google.com> In-Reply-To: <20260728-gmem-inplace-conversion-v9-0-35f9aec2aed2@google.com> To: 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 , John Hubbard , Peter Xu , Jason Gunthorpe , Vlastimil Babka , Baoquan He 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, Ackerley Tng , Xiaoyao Li X-Mailer: b4 0.14.3 X-Developer-Signature: v=1; a=ed25519-sha256; t=1785285305; l=3207; i=ackerleytng@google.com; s=20260225; h=from:subject:message-id; bh=lo4Gzy+LZN1Xb6HGgda47M2L38FFpVZSB/P8dGlPKnM=; b=iEl0F2TmAh0HZuon0fRMIFG6VBy/MiktRfz/Bj49faa9Dv9LwvJU/ac1q5NU5RtzUbPED6Mom CuTa53vGcDmDExd5Ne/IVQgruY+UWXcUTv6MotbNwwAV+nSViIoAe0o X-Developer-Key: i=ackerleytng@google.com; a=ed25519; pk=sAZDYXdm6Iz8FHitpHeFlCMXwabodTm7p8/3/8xUxuU= X-Endpoint-Received: by B4 Relay for ackerleytng@google.com/20260225 with auth_id=649 X-Original-From: Ackerley Tng Reply-To: ackerleytng@google.com From: Sean Christopherson Introduce a generic kvm_mem_is_private() interface using a static call to determine if a GFN is private. This allows the implementation for checking a GFN's private/shared status to be set at runtime. In preparation for choosing implementations between a guest_memfd lookup and the existing VM attribute lookup, rename the existing VM-attribute-based check to kvm_vm_mem_is_private to emphasize that it looks up VM attributes. Signed-off-by: Sean Christopherson Reviewed-by: Xiaoyao Li Reviewed-by: Fuad Tabba Tested-by: Shivank Garg Signed-off-by: Ackerley Tng --- include/linux/kvm_host.h | 14 ++++++++++++-- virt/kvm/kvm_main.c | 15 +++++++++++++++ 2 files changed, 27 insertions(+), 2 deletions(-) diff --git a/include/linux/kvm_host.h b/include/linux/kvm_host.h index 297cb06302223..438567e3fa6a1 100644 --- a/include/linux/kvm_host.h +++ b/include/linux/kvm_host.h @@ -2572,16 +2572,26 @@ bool kvm_arch_pre_set_vm_memory_attributes(struct kvm *kvm, bool kvm_arch_post_set_vm_memory_attributes(struct kvm *kvm, struct kvm_gfn_range *range); -static inline bool kvm_mem_is_private(struct kvm *kvm, gfn_t gfn) +static inline bool kvm_vm_mem_is_private(struct kvm *kvm, gfn_t gfn) { return kvm_get_vm_memory_attributes(kvm, gfn) & KVM_MEMORY_ATTRIBUTE_PRIVATE; } +#endif /* CONFIG_KVM_VM_MEMORY_ATTRIBUTES */ + +#ifdef kvm_arch_has_private_mem +typedef bool (kvm_mem_is_private_t)(struct kvm *kvm, gfn_t gfn); +DECLARE_STATIC_CALL(__kvm_mem_is_private, kvm_mem_is_private_t); + +static inline bool kvm_mem_is_private(struct kvm *kvm, gfn_t gfn) +{ + return static_call(__kvm_mem_is_private)(kvm, gfn); +} #else static inline bool kvm_mem_is_private(struct kvm *kvm, gfn_t gfn) { return false; } -#endif /* CONFIG_KVM_VM_MEMORY_ATTRIBUTES */ +#endif /* kvm_arch_has_private_mem */ #ifdef CONFIG_KVM_GUEST_MEMFD int kvm_gmem_get_pfn(struct kvm *kvm, struct kvm_memory_slot *slot, diff --git a/virt/kvm/kvm_main.c b/virt/kvm/kvm_main.c index 6f0bcab7a0ebc..80317d2c15d07 100644 --- a/virt/kvm/kvm_main.c +++ b/virt/kvm/kvm_main.c @@ -2627,6 +2627,20 @@ static int kvm_vm_ioctl_set_mem_attributes(struct kvm *kvm, } #endif /* CONFIG_KVM_VM_MEMORY_ATTRIBUTES */ +#ifdef kvm_arch_has_private_mem +DEFINE_STATIC_CALL_RET0(__kvm_mem_is_private, kvm_mem_is_private_t); +EXPORT_STATIC_CALL_GPL(__kvm_mem_is_private); + +static void kvm_init_memory_attributes(void) +{ +#ifdef CONFIG_KVM_VM_MEMORY_ATTRIBUTES + static_call_update(__kvm_mem_is_private, kvm_vm_mem_is_private); +#endif +} +#else +static void kvm_init_memory_attributes(void) { } +#endif + struct kvm_memory_slot *gfn_to_memslot(struct kvm *kvm, gfn_t gfn) { return __gfn_to_memslot(kvm_memslots(kvm), gfn); @@ -6539,6 +6553,7 @@ int kvm_init(unsigned vcpu_size, unsigned vcpu_align, struct module *module) kvm_preempt_ops.sched_in = kvm_sched_in; kvm_preempt_ops.sched_out = kvm_sched_out; + kvm_init_memory_attributes(); kvm_init_debug(); r = kvm_vfio_ops_init(); -- 2.55.0.508.g3f0d502094-goog