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 C20631DEFE8; Sat, 23 May 2026 00:18:03 +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=1779495483; cv=none; b=gLQKYT7/p6JoB2zo87QimRflDLpHIob+uN8awDVvEN8uGYPTOmzQRGEWKWZnn2hkugnhiURwKOtHYO7rvx0p02FUVvYKkZDwnYXWASlajBdqNznRxwSyWf9tg5NDpl4OG+kBAR7+0M5xdbAk22CWN/vEPnkgB9yN4JKmXtlh8lk= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1779495483; c=relaxed/simple; bh=KRNbaEsSfNYktqK+TdhL9wK5NA+yc8w3OKg5NAanuCc=; h=From:Date:Subject:MIME-Version:Content-Type:Message-Id:References: In-Reply-To:To:Cc; b=dwYuz8lisTnt6LpwNam0rT3nsxgIXNvxgBiZUq7GFSBpdEXWfxnWK1Qgo6Ue0tK6iSg7BSIaUBi43XAvbBmK64FBKx6M36EiUZaJLKzMSmf5DrUb7/9Oa2nBh5AwZTC43VZoh47J4NZQTgbL1YDsbUpM3rGRGZT6AWtWl/9n6lY= ARC-Authentication-Results:i=1; smtp.subspace.kernel.org; dkim=pass (2048-bit key) header.d=kernel.org header.i=@kernel.org header.b=ssEnp+Vi; 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="ssEnp+Vi" Received: by smtp.kernel.org (Postfix) with ESMTPS id 9E8C9C4AF53; Sat, 23 May 2026 00:18:03 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=k20201202; t=1779495483; bh=KRNbaEsSfNYktqK+TdhL9wK5NA+yc8w3OKg5NAanuCc=; h=From:Date:Subject:References:In-Reply-To:To:Cc:Reply-To:From; b=ssEnp+Vid6mz9P8b14IeQGHzJPNYLG9B6D1pjL5rDmpdoqstNHSRrqVOf8zKhzvvc HafiNJwvOSPrnhcgyQL8y9PhJB6GaEAsMEy7TzTSk+EPxYaihGfhkw5+l2frfUrE0U bW4KhryqtChlkykApqLcl/1LQxioyO1Ys9jKEPRmoaOFWU6ii1UWLnJRF8CPPv4wZg 1P4bM9jlU12qlNXpGKW2EeBfp0p3I0toNHBJ0xHjbLu0vNJrVFF2npPKnAGOBzb116 OotgeEo1Pcjzf7t4u5tE4kbbLr3wQkhs2XD+PXWH3flHNZ/xLotIPmNHiJ6oczTqtq JoGA+9YGaRqBw== 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 8DBB4CD5BBD; Sat, 23 May 2026 00:18:03 +0000 (UTC) From: Ackerley Tng via B4 Relay Date: Fri, 22 May 2026 17:17:48 -0700 Subject: [PATCH v7 06/42] KVM: guest_memfd: Update kvm_gmem_populate() to use gmem attributes Precedence: bulk X-Mailing-List: linux-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: <20260522-gmem-inplace-conversion-v7-6-2f0fae496530@google.com> References: <20260522-gmem-inplace-conversion-v7-0-2f0fae496530@google.com> In-Reply-To: <20260522-gmem-inplace-conversion-v7-0-2f0fae496530@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, ira.weiny@intel.com, 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 , Baoquan He , Barry Song , Axel Rasmussen , Yuanchu Xie , Wei Xu , Youngjun Park , Qi Zheng , Shakeel Butt , Kiryl Shutsemau , 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, Ackerley Tng X-Mailer: b4 0.14.3 X-Developer-Signature: v=1; a=ed25519-sha256; t=1779495480; l=5845; i=ackerleytng@google.com; s=20260225; h=from:subject:message-id; bh=T09Pq5q0ZyF3JHYQzQ4Ky1UwiTvUdLqSOIHXfWHbSsE=; b=hPW4FLiUYOMXm2sa6dFvqWbQZ6f9551sdFzSpJa8eViKfRt/Fb9zxvr5r7yU1mHBr+rzE53FI v+4bSkxqzqQDiZ/n0DOXpdVDlKP+2AhaUIhoRZl9De/Tv9iHOgJimJ3 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: Ackerley Tng Update the guest_memfd populate() flow to pull memory attributes from the gmem instance instead of the VM when KVM is not configured to track shared/private status in the VM. Rename the per-VM API to make it clear that it retrieves per-VM attributes, i.e. is not suitable for use outside of flows that are specific to generic per-VM attributes. Co-developed-by: Sean Christopherson Signed-off-by: Sean Christopherson Reviewed-by: Fuad Tabba Signed-off-by: Ackerley Tng --- arch/x86/kvm/mmu/mmu.c | 2 +- include/linux/kvm_host.h | 14 +++++++++++++- virt/kvm/guest_memfd.c | 24 +++++++++++++++++++++--- virt/kvm/kvm_main.c | 8 +++----- 4 files changed, 38 insertions(+), 10 deletions(-) diff --git a/arch/x86/kvm/mmu/mmu.c b/arch/x86/kvm/mmu/mmu.c index b53a0c4b4dfca..3f70859232b07 100644 --- a/arch/x86/kvm/mmu/mmu.c +++ b/arch/x86/kvm/mmu/mmu.c @@ -8060,7 +8060,7 @@ static bool hugepage_has_attrs(struct kvm *kvm, struct kvm_memory_slot *slot, const unsigned long end = start + KVM_PAGES_PER_HPAGE(level); if (level == PG_LEVEL_2M) - return kvm_range_has_memory_attributes(kvm, start, end, ~0, attrs); + return kvm_range_has_vm_memory_attributes(kvm, start, end, ~0, attrs); for (gfn = start; gfn < end; gfn += KVM_PAGES_PER_HPAGE(level - 1)) { if (hugepage_test_mixed(slot, gfn, level - 1) || diff --git a/include/linux/kvm_host.h b/include/linux/kvm_host.h index 7de85474c75bd..3039b291e4b09 100644 --- a/include/linux/kvm_host.h +++ b/include/linux/kvm_host.h @@ -2549,12 +2549,24 @@ static inline bool kvm_mem_is_private(struct kvm *kvm, gfn_t gfn) #endif #ifdef CONFIG_KVM_VM_MEMORY_ATTRIBUTES -bool kvm_range_has_memory_attributes(struct kvm *kvm, gfn_t start, gfn_t end, +extern bool vm_memory_attributes; +bool kvm_range_has_vm_memory_attributes(struct kvm *kvm, gfn_t start, gfn_t end, unsigned long mask, unsigned long attrs); bool kvm_arch_pre_set_memory_attributes(struct kvm *kvm, struct kvm_gfn_range *range); bool kvm_arch_post_set_memory_attributes(struct kvm *kvm, struct kvm_gfn_range *range); +#else +#define vm_memory_attributes false +static inline bool kvm_range_has_vm_memory_attributes(struct kvm *kvm, + gfn_t start, gfn_t end, + unsigned long mask, + unsigned long attrs) +{ + WARN_ONCE(1, "Unexpected call to kvm_range_has_vm_memory_attributes()"); + + return false; +} #endif /* CONFIG_KVM_VM_MEMORY_ATTRIBUTES */ unsigned long kvm_gmem_get_memory_attributes(struct kvm *kvm, gfn_t gfn); diff --git a/virt/kvm/guest_memfd.c b/virt/kvm/guest_memfd.c index c55879e033d96..78e5435967341 100644 --- a/virt/kvm/guest_memfd.c +++ b/virt/kvm/guest_memfd.c @@ -930,12 +930,31 @@ int kvm_gmem_get_pfn(struct kvm *kvm, struct kvm_memory_slot *slot, EXPORT_SYMBOL_FOR_KVM_INTERNAL(kvm_gmem_get_pfn); #ifdef CONFIG_HAVE_KVM_ARCH_GMEM_POPULATE +static bool kvm_gmem_range_is_private(struct gmem_inode *gi, pgoff_t index, + size_t nr_pages, struct kvm *kvm, gfn_t gfn) +{ + pgoff_t end = index + nr_pages - 1; + void *entry; + + if (vm_memory_attributes) + return kvm_range_has_vm_memory_attributes(kvm, gfn, gfn + nr_pages, + KVM_MEMORY_ATTRIBUTE_PRIVATE, + KVM_MEMORY_ATTRIBUTE_PRIVATE); + + mt_for_each(&gi->attributes, entry, index, end) { + if (xa_to_value(entry) != KVM_MEMORY_ATTRIBUTE_PRIVATE) + return false; + } + + return true; +} static long __kvm_gmem_populate(struct kvm *kvm, struct kvm_memory_slot *slot, struct file *file, gfn_t gfn, struct page *src_page, kvm_gmem_populate_cb post_populate, void *opaque) { pgoff_t index = kvm_gmem_get_index(slot, gfn); + struct gmem_inode *gi; struct folio *folio; kvm_pfn_t pfn; int ret; @@ -950,9 +969,8 @@ static long __kvm_gmem_populate(struct kvm *kvm, struct kvm_memory_slot *slot, folio_unlock(folio); - if (!kvm_range_has_memory_attributes(kvm, gfn, gfn + 1, - KVM_MEMORY_ATTRIBUTE_PRIVATE, - KVM_MEMORY_ATTRIBUTE_PRIVATE)) { + gi = GMEM_I(file_inode(file)); + if (!kvm_gmem_range_is_private(gi, index, 1, kvm, gfn)) { ret = -EINVAL; goto out_put_folio; } diff --git a/virt/kvm/kvm_main.c b/virt/kvm/kvm_main.c index 4139e903f756a..0a4024948711a 100644 --- a/virt/kvm/kvm_main.c +++ b/virt/kvm/kvm_main.c @@ -103,9 +103,7 @@ module_param(allow_unsafe_mappings, bool, 0444); #ifdef CONFIG_KVM_MEMORY_ATTRIBUTES #ifdef CONFIG_KVM_VM_MEMORY_ATTRIBUTES -static bool vm_memory_attributes = true; -#else -#define vm_memory_attributes false +bool vm_memory_attributes = true; #endif DEFINE_STATIC_CALL_RET0(__kvm_get_memory_attributes, kvm_get_memory_attributes_t); EXPORT_SYMBOL_FOR_KVM_INTERNAL(STATIC_CALL_KEY(__kvm_get_memory_attributes)); @@ -2450,7 +2448,7 @@ static unsigned long kvm_get_vm_memory_attributes(struct kvm *kvm, gfn_t gfn) * Returns true if _all_ gfns in the range [@start, @end) have attributes * such that the bits in @mask match @attrs. */ -bool kvm_range_has_memory_attributes(struct kvm *kvm, gfn_t start, gfn_t end, +bool kvm_range_has_vm_memory_attributes(struct kvm *kvm, gfn_t start, gfn_t end, unsigned long mask, unsigned long attrs) { XA_STATE(xas, &kvm->mem_attr_array, start); @@ -2584,7 +2582,7 @@ static int kvm_vm_set_mem_attributes(struct kvm *kvm, gfn_t start, gfn_t end, mutex_lock(&kvm->slots_lock); /* Nothing to do if the entire range has the desired attributes. */ - if (kvm_range_has_memory_attributes(kvm, start, end, ~0, attributes)) + if (kvm_range_has_vm_memory_attributes(kvm, start, end, ~0, attributes)) goto out_unlock; /* -- 2.54.0.794.g4f17f83d09-goog