From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from mail-pl1-f201.google.com (mail-pl1-f201.google.com [209.85.214.201]) (using TLSv1.2 with cipher ECDHE-RSA-AES128-GCM-SHA256 (128/128 bits)) (No client certificate requested) by smtp.subspace.kernel.org (Postfix) with ESMTPS id C55CB2C21D5 for ; Fri, 17 Oct 2025 20:12:57 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.client-ip=209.85.214.201 ARC-Seal:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1760731981; cv=none; b=o9jZ9/2PyT3vZ4DfA/vJotN5khtRlZuf5uLf31uZZNZ6Sib5iPWuUisbMleq24TszGhP29j06ucoURqH+pJp3i6bryHls2+ywGEdLoxnxAuBOCkjUFqGMvO/z3TY0fVahd41C2douIb/Wak9ZQbbD+oUj9g9To42RXcdEhh1tZo= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1760731981; c=relaxed/simple; bh=sZ5H+zHTHSNfIlVrFkaHh5egYLM8pq0dUeGZ7JIG6Xs=; h=Date:In-Reply-To:Mime-Version:References:Message-ID:Subject:From: To:Cc:Content-Type; b=iQ+KiNt4axW2cSyIgsrVa4qBI44Bd9sfX8R12fJ3jujBWrTtSaf3IPZspHZuRSY++KZeZ2YAeiP7mRoFuu+2XONDRqLpPKUe+iVmSPXm3JDG2dAt056CRg46fz9iOsyK5L/4yxWFCrFrliVljXJNj6AT+K6WJ/ftBtHQPaCRg0I= ARC-Authentication-Results:i=1; smtp.subspace.kernel.org; dmarc=pass (p=reject dis=none) header.from=google.com; spf=pass smtp.mailfrom=flex--ackerleytng.bounces.google.com; dkim=pass (2048-bit key) header.d=google.com header.i=@google.com header.b=lzpPKRcL; arc=none smtp.client-ip=209.85.214.201 Authentication-Results: smtp.subspace.kernel.org; dmarc=pass (p=reject dis=none) header.from=google.com Authentication-Results: smtp.subspace.kernel.org; spf=pass smtp.mailfrom=flex--ackerleytng.bounces.google.com Authentication-Results: smtp.subspace.kernel.org; dkim=pass (2048-bit key) header.d=google.com header.i=@google.com header.b="lzpPKRcL" Received: by mail-pl1-f201.google.com with SMTP id d9443c01a7336-290ab8f5af6so18803835ad.3 for ; Fri, 17 Oct 2025 13:12:57 -0700 (PDT) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=google.com; s=20230601; t=1760731976; x=1761336776; darn=vger.kernel.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=FZrm0bBpyP9vTvkArtXHnxbGIMZ4Py8QfqHZJRCW2ZI=; b=lzpPKRcLKn7MuY/GyTUjm6oTNcja3GssnL6Sh98JTFPltZzucgpH0dY5VkwRJUj6gi TLn3Ii7TG7q+u828a1Wtgr52vi99N3sAXJY4lWgT1leqduOKVwusPB/MMILeZE4PVoez gHO44Da4p87tdZ5gKksWgdRW3WyItgN114Aoyf2272EPxeZxQo9atCgzj1/YvxawGk9S Tzianva0MEecIaln4SE1oAzNBXjHjrKCf0I0D6olJbHsfiW2h4NGJHDbus7se7PWrRLw BId86jKshxiqeyH2ErnQP/su2BySWwejR+6GWCM+YDqUqIFFI7dbjlGGxqqyiHTsvpW5 ++zg== X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20230601; t=1760731976; x=1761336776; 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=FZrm0bBpyP9vTvkArtXHnxbGIMZ4Py8QfqHZJRCW2ZI=; b=lpoJD+T1ZbAh/oD00/k8vKCKwHOxru0uOHKbg40BN5PlwUjI8CKTxN5P1JUbID5YxI jZjnagrMETdQZ0q+/BWnDSwtEr65ul0OpdL8dWkrm8L0oxCNC2jjnh29UShRUa1mktlS UR8I4Kkcm9qpcy5hVf/CYo8J8mR14vC5HrsJAC4ZMGUhCtjH5KTDaiFpcLVCB9C6BrIm IVTIXRaYRs0Vbh4XO6ZSWgd8c8bJGT+FAwnhhJdDfDbZX5HRYRIfft5DqviVWYIOiaTX ekrAgb4ATYZ5f/r8WLpVwAyZ4RRi4bMj15sAh3jEWd+vlczBRiiLz/+uIisKld97nht4 dU/w== X-Forwarded-Encrypted: i=1; AJvYcCXpvLQJyWkWaTzuXcBy1peYxZ7iK7gHoXhtQ9eMuF6Ki5dLNLLj15qfZ4ER1rI1FEbn5dOH1Jc+SbyUcycgD+4eldo=@vger.kernel.org X-Gm-Message-State: AOJu0Yx8UuW0jN0Q824rFpl9ownG2EZ4hHjcK/w5pAsDym/DOMDPMR37 VvVCIZRdkDk/UWi8MJO+ctSfQpMByBaJViuyyTgDfAmEZyLR+DOTPoEmzScyzJhXsedTSOK4hMP ZNX/d0Q2HYQJAS1GIt0AiXiC0qg== X-Google-Smtp-Source: AGHT+IHeEcTma0Vf9iP7bayAuL5X24WwVW+rZLP1mtrjCO7SF8PjjpL45P1H1MJ3MINmLICN5Aa9w6/jdnFaODUMng== X-Received: from pleg12.prod.google.com ([2002:a17:902:e38c:b0:268:4e0:9c09]) (user=ackerleytng job=prod-delivery.src-stubby-dispatcher) by 2002:a17:902:ec83:b0:276:305b:14a7 with SMTP id d9443c01a7336-290ca30d76dmr61848425ad.33.1760731975492; Fri, 17 Oct 2025 13:12:55 -0700 (PDT) Date: Fri, 17 Oct 2025 13:11:57 -0700 In-Reply-To: Precedence: bulk X-Mailing-List: linux-trace-kernel@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: Mime-Version: 1.0 References: X-Mailer: git-send-email 2.51.0.858.gf9c4a03a3a-goog Message-ID: <727482ec42baa50cb1488ad89d02e732defda3db.1760731772.git.ackerleytng@google.com> Subject: [RFC PATCH v1 16/37] KVM: selftests: Add support for mmap() on guest_memfd in core library From: Ackerley Tng To: 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 Cc: ackerleytng@google.com, 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, jroedel@suse.de, 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, seanjc@google.com, shakeel.butt@linux.dev, shuah@kernel.org, steven.price@arm.com, steven.sistare@oracle.com, 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, wei.w.wang@intel.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, zhiquan1.li@intel.com Content-Type: text/plain; charset="UTF-8" From: Sean Christopherson Accept gmem_flags in vm_mem_add() to be able to create a guest_memfd within vm_mem_add(). When vm_mem_add() is used to set up a guest_memfd for a memslot, set up the provided (or created) gmem_fd as the fd for the user memory region. This makes it available to be mmap()-ed from just like fds from other memory sources. mmap() from guest_memfd using the provided gmem_flags and gmem_offset. Add a kvm_slot_to_fd() helper to provide convenient access to the file descriptor of a memslot. Update existing callers of vm_mem_add() to pass 0 for gmem_flags to preserve existing behavior. Signed-off-by: Sean Christopherson [For guest_memfds, mmap() using gmem_offset instead of 0 all the time.] Signed-off-by: Ackerley Tng --- tools/testing/selftests/kvm/include/kvm_util.h | 7 ++++++- tools/testing/selftests/kvm/lib/kvm_util.c | 18 ++++++++++-------- .../kvm/x86/private_mem_conversions_test.c | 2 +- 3 files changed, 17 insertions(+), 10 deletions(-) diff --git a/tools/testing/selftests/kvm/include/kvm_util.h b/tools/testing/selftests/kvm/include/kvm_util.h index 45159638d5dde..de8ae9be19067 100644 --- a/tools/testing/selftests/kvm/include/kvm_util.h +++ b/tools/testing/selftests/kvm/include/kvm_util.h @@ -678,7 +678,7 @@ void vm_userspace_mem_region_add(struct kvm_vm *vm, uint32_t flags); void vm_mem_add(struct kvm_vm *vm, enum vm_mem_backing_src_type src_type, uint64_t gpa, uint32_t slot, uint64_t npages, uint32_t flags, - int guest_memfd_fd, uint64_t guest_memfd_offset); + int gmem_fd, uint64_t gmem_offset, uint64_t gmem_flags); #ifndef vm_arch_has_protected_memory static inline bool vm_arch_has_protected_memory(struct kvm_vm *vm) @@ -711,6 +711,11 @@ void *addr_gva2hva(struct kvm_vm *vm, vm_vaddr_t gva); vm_paddr_t addr_hva2gpa(struct kvm_vm *vm, void *hva); void *addr_gpa2alias(struct kvm_vm *vm, vm_paddr_t gpa); +static inline int kvm_slot_to_fd(struct kvm_vm *vm, uint32_t slot) +{ + return memslot2region(vm, slot)->fd; +} + #ifndef vcpu_arch_put_guest #define vcpu_arch_put_guest(mem, val) do { (mem) = (val); } while (0) #endif diff --git a/tools/testing/selftests/kvm/lib/kvm_util.c b/tools/testing/selftests/kvm/lib/kvm_util.c index 8b714270cf381..19c0445c0b296 100644 --- a/tools/testing/selftests/kvm/lib/kvm_util.c +++ b/tools/testing/selftests/kvm/lib/kvm_util.c @@ -944,12 +944,13 @@ void vm_set_user_memory_region2(struct kvm_vm *vm, uint32_t slot, uint32_t flags /* FIXME: This thing needs to be ripped apart and rewritten. */ void vm_mem_add(struct kvm_vm *vm, enum vm_mem_backing_src_type src_type, uint64_t gpa, uint32_t slot, uint64_t npages, uint32_t flags, - int gmem_fd, uint64_t gmem_offset) + int gmem_fd, uint64_t gmem_offset, uint64_t gmem_flags) { int ret; struct userspace_mem_region *region; size_t backing_src_pagesz = get_backing_src_pagesz(src_type); size_t mem_size = npages * vm->page_size; + off_t mmap_offset; size_t alignment; TEST_REQUIRE_SET_USER_MEMORY_REGION2(); @@ -1028,8 +1029,6 @@ void vm_mem_add(struct kvm_vm *vm, enum vm_mem_backing_src_type src_type, if (flags & KVM_MEM_GUEST_MEMFD) { if (gmem_fd < 0) { - uint32_t gmem_flags = 0; - TEST_ASSERT(!gmem_offset, "Offset must be zero when creating new guest_memfd"); gmem_fd = vm_create_guest_memfd(vm, mem_size, gmem_flags); @@ -1050,13 +1049,16 @@ void vm_mem_add(struct kvm_vm *vm, enum vm_mem_backing_src_type src_type, } region->fd = -1; - if (backing_src_is_shared(src_type)) + if (flags & KVM_MEM_GUEST_MEMFD && gmem_flags & GUEST_MEMFD_FLAG_MMAP) + region->fd = kvm_dup(gmem_fd); + else if (backing_src_is_shared(src_type)) region->fd = kvm_memfd_alloc(region->mmap_size, src_type == VM_MEM_SRC_SHARED_HUGETLB); - region->mmap_start = kvm_mmap(region->mmap_size, PROT_READ | PROT_WRITE, - vm_mem_backing_src_alias(src_type)->flag, - region->fd); + mmap_offset = flags & KVM_MEM_GUEST_MEMFD ? gmem_offset : 0; + region->mmap_start = __kvm_mmap(region->mmap_size, PROT_READ | PROT_WRITE, + vm_mem_backing_src_alias(src_type)->flag, + region->fd, mmap_offset); TEST_ASSERT(!is_backing_src_hugetlb(src_type) || region->mmap_start == align_ptr_up(region->mmap_start, backing_src_pagesz), @@ -1117,7 +1119,7 @@ void vm_userspace_mem_region_add(struct kvm_vm *vm, uint64_t gpa, uint32_t slot, uint64_t npages, uint32_t flags) { - vm_mem_add(vm, src_type, gpa, slot, npages, flags, -1, 0); + vm_mem_add(vm, src_type, gpa, slot, npages, flags, -1, 0, 0); } /* diff --git a/tools/testing/selftests/kvm/x86/private_mem_conversions_test.c b/tools/testing/selftests/kvm/x86/private_mem_conversions_test.c index 1969f4ab9b280..41f6b38f04071 100644 --- a/tools/testing/selftests/kvm/x86/private_mem_conversions_test.c +++ b/tools/testing/selftests/kvm/x86/private_mem_conversions_test.c @@ -399,7 +399,7 @@ static void test_mem_conversions(enum vm_mem_backing_src_type src_type, uint32_t for (i = 0; i < nr_memslots; i++) vm_mem_add(vm, src_type, BASE_DATA_GPA + slot_size * i, BASE_DATA_SLOT + i, slot_size / vm->page_size, - KVM_MEM_GUEST_MEMFD, memfd, slot_size * i); + KVM_MEM_GUEST_MEMFD, memfd, slot_size * i, 0); for (i = 0; i < nr_vcpus; i++) { uint64_t gpa = BASE_DATA_GPA + i * per_cpu_size; -- 2.51.0.858.gf9c4a03a3a-goog