From patchwork Thu Sep 14 01:55:04 2023 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Sean Christopherson X-Patchwork-Id: 13384013 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 61A1EEE0216 for ; Thu, 14 Sep 2023 01:55:55 +0000 (UTC) Received: by kanga.kvack.org (Postfix) id 88C216B0289; Wed, 13 Sep 2023 21:55:51 -0400 (EDT) Received: by kanga.kvack.org (Postfix, from userid 40) id 8387B6B028F; Wed, 13 Sep 2023 21:55:51 -0400 (EDT) X-Delivered-To: int-list-linux-mm@kvack.org Received: by kanga.kvack.org (Postfix, from userid 63042) id 68E476B0297; Wed, 13 Sep 2023 21:55:51 -0400 (EDT) X-Delivered-To: linux-mm@kvack.org Received: from relay.hostedemail.com (smtprelay0017.hostedemail.com [216.40.44.17]) by kanga.kvack.org (Postfix) with ESMTP id 4FA766B0289 for ; Wed, 13 Sep 2023 21:55:51 -0400 (EDT) Received: from smtpin02.hostedemail.com (a10.router.float.18 [10.200.18.1]) by unirelay02.hostedemail.com (Postfix) with ESMTP id 25238120EF6 for ; Thu, 14 Sep 2023 01:55:51 +0000 (UTC) X-FDA: 81233536902.02.5432784 Received: from mail-yw1-f202.google.com (mail-yw1-f202.google.com [209.85.128.202]) by imf21.hostedemail.com (Postfix) with ESMTP id 568281C0002 for ; Thu, 14 Sep 2023 01:55:49 +0000 (UTC) Authentication-Results: imf21.hostedemail.com; dkim=pass header.d=google.com header.s=20230601 header.b=AAa40jtb; spf=pass (imf21.hostedemail.com: domain of 3JGgCZQYKCC0bNJWSLPXXPUN.LXVURWdg-VVTeJLT.XaP@flex--seanjc.bounces.google.com designates 209.85.128.202 as permitted sender) smtp.mailfrom=3JGgCZQYKCC0bNJWSLPXXPUN.LXVURWdg-VVTeJLT.XaP@flex--seanjc.bounces.google.com; dmarc=pass (policy=reject) header.from=google.com ARC-Seal: i=1; s=arc-20220608; d=hostedemail.com; t=1694656549; a=rsa-sha256; cv=none; b=dM5d5ohBL8ZTFcs7rzEqB4NhlD2XESA4doDvjHuVn6+xRF+qtUXuzya4UvjGxCPUi40hpS Bkgt1dlfLPUR+skJF/Wm0CsiEdC7hyEX4nmve/dwukk105XJF2jZbLez2Lk0BokHXZ/G5w TdX9+ew1SPTnthqnl2U9AqLh2XOaI3o= ARC-Authentication-Results: i=1; imf21.hostedemail.com; dkim=pass header.d=google.com header.s=20230601 header.b=AAa40jtb; spf=pass (imf21.hostedemail.com: domain of 3JGgCZQYKCC0bNJWSLPXXPUN.LXVURWdg-VVTeJLT.XaP@flex--seanjc.bounces.google.com designates 209.85.128.202 as permitted sender) smtp.mailfrom=3JGgCZQYKCC0bNJWSLPXXPUN.LXVURWdg-VVTeJLT.XaP@flex--seanjc.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=1694656549; h=from:from:sender:reply-to: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=BhxGep0GRUEwAUAzFvnYRN6yWfiwAK/IRlQcI8pBhpQ=; b=lQAvpHPUMufXjOQeYxCWnD5M10fNTIwOOCKSlXWdKNx+q1S8LVMINn8QIL2Bs5/fdjzZZ0 ZHFyc78CUF/sfRF9oOFOzfXLl3JvBdX6godfvMf+cSbLnXuYs1MtFmFVKDvK8V6xXhcIt5 gXtBRR619waryysIfc8Gi5D8LgkpkXc= Received: by mail-yw1-f202.google.com with SMTP id 00721157ae682-59b56dab74bso6570407b3.2 for ; Wed, 13 Sep 2023 18:55:49 -0700 (PDT) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=google.com; s=20230601; t=1694656548; x=1695261348; darn=kvack.org; h=cc:to:from:subject:message-id:references:mime-version:in-reply-to :date:reply-to:from:to:cc:subject:date:message-id:reply-to; bh=BhxGep0GRUEwAUAzFvnYRN6yWfiwAK/IRlQcI8pBhpQ=; b=AAa40jtb0aSHjCvdffJkQL0wAExm3+HyzUq7UOcxEItWrPJfF3uZ0JpBSi/NPvO7kA ScMrD5bC331uFeIXrbuzS1SLYu/4LMU6zlk4fPAK4NNDsihmHgTZLXF4iKEvvnxvLZBY 7WzJn8npVvbTzqhJaTVnlPbVK9Uh1kaaIQak+f3KUKgeALwiiYaqohgG9s882XRmrjCm kA1UxXfXJW+L++A/7G4RE7KifKh66SukGcCQwULuFoBfiZuwBbHj8YN5bRPFYoyH7xkd g40+6GDWJC6aphU2k1MN9igwidFDlhLKe/rbMsk8bvz8SlrWR2uUG+M+nyWulWjs8jOj Rm/Q== X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20230601; t=1694656548; x=1695261348; h=cc:to:from:subject:message-id:references:mime-version:in-reply-to :date:reply-to:x-gm-message-state:from:to:cc:subject:date:message-id :reply-to; bh=BhxGep0GRUEwAUAzFvnYRN6yWfiwAK/IRlQcI8pBhpQ=; b=pEbF/VaSXFYv4eQVOgV/3gRiNBpWPnPdEOYNmtROjBdzpkkCCGvL7FoRWFdV1WYzlj zKuThYvR+bO/ZHqDlFEQnhB/yjLlojkIQdyUakjdcpRe/H4ttN7uNv37Vj5cQPq+4noo YEOcyKLwRUprdJMuXmBtt1MQ/JxZDH6n7eCqK5NiujHNGESdtXfAkLk8Qfl7JECx32Yb pEHwXGrTdYp/zOSVYckeGIHWXZa26z0WIhCzbqivyGPxncrLCpqbn+YcL099/2YjZjxY Xt1ah8Vdna5lvZDAvQ22HlNCbtzJuy3pXe4HkivDTIQ3OW9zkrc5iaWpZ8uA7jow3k/C x7vg== X-Gm-Message-State: AOJu0YwiWGtUSleKtbD5ViBQqqAk56/SsFFZhvOmuhlpTqyL8AU4As/K O/37U0Aa/9zyvS/JYWXX6ImeZzs/7RA= X-Google-Smtp-Source: AGHT+IFIu1rjOq9FW+JbDj5fY4BKSa/epsGGWccSSMIHRlmCarPy2ezJLxiJZod49VfvzwgQV9RD5huQPI8= X-Received: from zagreus.c.googlers.com ([fda3:e722:ac3:cc00:7f:e700:c0a8:5c37]) (user=seanjc job=sendgmr) by 2002:a25:4207:0:b0:d81:536d:2978 with SMTP id p7-20020a254207000000b00d81536d2978mr74175yba.2.1694656548405; Wed, 13 Sep 2023 18:55:48 -0700 (PDT) Reply-To: Sean Christopherson Date: Wed, 13 Sep 2023 18:55:04 -0700 In-Reply-To: <20230914015531.1419405-1-seanjc@google.com> Mime-Version: 1.0 References: <20230914015531.1419405-1-seanjc@google.com> X-Mailer: git-send-email 2.42.0.283.g2d96d420d3-goog Message-ID: <20230914015531.1419405-7-seanjc@google.com> Subject: [RFC PATCH v12 06/33] KVM: Introduce KVM_SET_USER_MEMORY_REGION2 From: Sean Christopherson To: Paolo Bonzini , Marc Zyngier , Oliver Upton , Huacai Chen , Michael Ellerman , Anup Patel , Paul Walmsley , Palmer Dabbelt , Albert Ou , Sean Christopherson , "Matthew Wilcox (Oracle)" , Andrew Morton , Paul Moore , James Morris , "Serge E. Hallyn" Cc: kvm@vger.kernel.org, linux-arm-kernel@lists.infradead.org, kvmarm@lists.linux.dev, linux-mips@vger.kernel.org, linuxppc-dev@lists.ozlabs.org, kvm-riscv@lists.infradead.org, linux-riscv@lists.infradead.org, linux-fsdevel@vger.kernel.org, linux-mm@kvack.org, linux-security-module@vger.kernel.org, linux-kernel@vger.kernel.org, Chao Peng , Fuad Tabba , Jarkko Sakkinen , Anish Moorthy , Yu Zhang , Isaku Yamahata , Xu Yilun , Vlastimil Babka , Vishal Annapurve , Ackerley Tng , Maciej Szmigiero , David Hildenbrand , Quentin Perret , Michael Roth , Wang , Liam Merwick , Isaku Yamahata , "Kirill A . Shutemov" X-Rspamd-Server: rspam08 X-Rspamd-Queue-Id: 568281C0002 X-Stat-Signature: yanac1ashiuasc4obonzeotah4bksdqp X-Rspam-User: X-HE-Tag: 1694656549-885707 X-HE-Meta: U2FsdGVkX1/9zjuLB7WC91g7XCsQvl1kxj55S4zhqzd1hvFz+sPafJ9MmlYK26w/pOkUG8WsQkGoy84Mmcq1WsDk0anzc7U3W+ko9yMmhYPR3RkBjo8buGSFdm1yDdNgtxbf7rpeO+GosqyTMn+909LqNHGaodLBu8bIlo9XwPU1LlfdJYfZVkZmgWRQrTtudifnjAmziLGWA2vyoVlE/2OpvftIYo5edQov/NoL8qsOKDwWebDX1cNDAPEaBvr0t8TiPu2f+wM0GTm2UiIb/Mib2ofyLF0K/3vnTMzGELohTImpK8QrzWdOJrwiuEXG1nUrMxqzlREc6tY7SBEaFeYH0RVzzTc9+vNl0EK5cNvQUcvy1sh20jluZQXUWKcfGnS0vK3bqpGjT9tmNeIwGy5gcGjIegZM0JXsrTMJLL98U2mRpFRdxZFV4BRZUeFBrEhz4Fv6IyAmVwE5t1cIbqlWsTX2psy2tWwS/tqzimS8a4TJLxH7kTXT2xIHmGI+M39g6X8AX9VFpMcLlHdgVlFFZeZefQMOJKbZOF+5hWIe/kBbEpxDLJjrKcF1p2BWUmeL6dSAHyqIeInNh5Ykk20rCpYE4oV/KqRPRZwlX4PW5ljyWokMEU5GZRKg2jD+eNm05sOkIpcRPoMyzxgjv1TMXxfygajU+PJ9yM0LF/Th5kA7lOO21FB/6D97IjOODpwVQz/CzmfLDLLDly7oiq1FunNkUslm6dJkOAg/5pRfwfG5JAwEoiWc6tnNwMpOErZAYwAUb9oUnC8T8sd9tIq8PoewFNnuCu++LZYjIBZm9vNejOaOWjcsPIp4QONW5qj2YelJzBIyqyskeErHtWXS1idZekxrDfER72W5PEkEX6x9e+C42DUNEydH4NTH+GoLE7r+XWFN/j2n4qOM63T56u8MIBnvBUEqj98FIiunpu8e8LRwGB7YR7MQTpRDc2XAUD8Ep+Maqz4tv7b uZPL0UFZ 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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: Introduce a "version 2" of KVM_SET_USER_MEMORY_REGION so that additional information can be supplied without setting userspace up to fail. The padding in the new kvm_userspace_memory_region2 structure will be used to pass a file descriptor in addition to the userspace_addr, i.e. allow userspace to point at a file descriptor and map memory into a guest that is NOT mapped into host userspace. Alternatively, KVM could simply add "struct kvm_userspace_memory_region2" without a new ioctl(), but as Paolo pointed out, adding a new ioctl() makes detection of bad flags a bit more robust, e.g. if the new fd field is guarded only by a flag and not a new ioctl(), then a userspace bug (setting a "bad" flag) would generate out-of-bounds access instead of an -EINVAL error. Cc: Jarkko Sakkinen Reviewed-by: Paolo Bonzini Signed-off-by: Sean Christopherson Reviewed-by: Xiaoyao Li --- arch/x86/kvm/x86.c | 2 +- include/linux/kvm_host.h | 4 ++-- include/uapi/linux/kvm.h | 13 +++++++++++++ virt/kvm/kvm_main.c | 38 ++++++++++++++++++++++++++++++-------- 4 files changed, 46 insertions(+), 11 deletions(-) diff --git a/arch/x86/kvm/x86.c b/arch/x86/kvm/x86.c index 6c9c81e82e65..8356907079e1 100644 --- a/arch/x86/kvm/x86.c +++ b/arch/x86/kvm/x86.c @@ -12447,7 +12447,7 @@ void __user * __x86_set_memory_region(struct kvm *kvm, int id, gpa_t gpa, } for (i = 0; i < KVM_ADDRESS_SPACE_NUM; i++) { - struct kvm_userspace_memory_region m; + struct kvm_userspace_memory_region2 m; m.slot = id | (i << 16); m.flags = 0; diff --git a/include/linux/kvm_host.h b/include/linux/kvm_host.h index 5faba69403ac..4e741ff27af3 100644 --- a/include/linux/kvm_host.h +++ b/include/linux/kvm_host.h @@ -1146,9 +1146,9 @@ enum kvm_mr_change { }; int kvm_set_memory_region(struct kvm *kvm, - const struct kvm_userspace_memory_region *mem); + const struct kvm_userspace_memory_region2 *mem); int __kvm_set_memory_region(struct kvm *kvm, - const struct kvm_userspace_memory_region *mem); + const struct kvm_userspace_memory_region2 *mem); void kvm_arch_free_memslot(struct kvm *kvm, struct kvm_memory_slot *slot); void kvm_arch_memslots_updated(struct kvm *kvm, u64 gen); int kvm_arch_prepare_memory_region(struct kvm *kvm, diff --git a/include/uapi/linux/kvm.h b/include/uapi/linux/kvm.h index 13065dd96132..bd1abe067f28 100644 --- a/include/uapi/linux/kvm.h +++ b/include/uapi/linux/kvm.h @@ -95,6 +95,16 @@ struct kvm_userspace_memory_region { __u64 userspace_addr; /* start of the userspace allocated memory */ }; +/* for KVM_SET_USER_MEMORY_REGION2 */ +struct kvm_userspace_memory_region2 { + __u32 slot; + __u32 flags; + __u64 guest_phys_addr; + __u64 memory_size; + __u64 userspace_addr; + __u64 pad[16]; +}; + /* * The bit 0 ~ bit 15 of kvm_userspace_memory_region::flags are visible for * userspace, other bits are reserved for kvm internal use which are defined @@ -1192,6 +1202,7 @@ struct kvm_ppc_resize_hpt { #define KVM_CAP_COUNTER_OFFSET 227 #define KVM_CAP_ARM_EAGER_SPLIT_CHUNK_SIZE 228 #define KVM_CAP_ARM_SUPPORTED_BLOCK_SIZES 229 +#define KVM_CAP_USER_MEMORY2 230 #ifdef KVM_CAP_IRQ_ROUTING @@ -1473,6 +1484,8 @@ struct kvm_vfio_spapr_tce { struct kvm_userspace_memory_region) #define KVM_SET_TSS_ADDR _IO(KVMIO, 0x47) #define KVM_SET_IDENTITY_MAP_ADDR _IOW(KVMIO, 0x48, __u64) +#define KVM_SET_USER_MEMORY_REGION2 _IOW(KVMIO, 0x49, \ + struct kvm_userspace_memory_region2) /* enable ucontrol for s390 */ struct kvm_s390_ucas_mapping { diff --git a/virt/kvm/kvm_main.c b/virt/kvm/kvm_main.c index 8d21757cd5e9..7c0e38752526 100644 --- a/virt/kvm/kvm_main.c +++ b/virt/kvm/kvm_main.c @@ -1571,7 +1571,7 @@ static void kvm_replace_memslot(struct kvm *kvm, } } -static int check_memory_region_flags(const struct kvm_userspace_memory_region *mem) +static int check_memory_region_flags(const struct kvm_userspace_memory_region2 *mem) { u32 valid_flags = KVM_MEM_LOG_DIRTY_PAGES; @@ -1973,7 +1973,7 @@ static bool kvm_check_memslot_overlap(struct kvm_memslots *slots, int id, * Must be called holding kvm->slots_lock for write. */ int __kvm_set_memory_region(struct kvm *kvm, - const struct kvm_userspace_memory_region *mem) + const struct kvm_userspace_memory_region2 *mem) { struct kvm_memory_slot *old, *new; struct kvm_memslots *slots; @@ -2077,7 +2077,7 @@ int __kvm_set_memory_region(struct kvm *kvm, EXPORT_SYMBOL_GPL(__kvm_set_memory_region); int kvm_set_memory_region(struct kvm *kvm, - const struct kvm_userspace_memory_region *mem) + const struct kvm_userspace_memory_region2 *mem) { int r; @@ -2089,7 +2089,7 @@ int kvm_set_memory_region(struct kvm *kvm, EXPORT_SYMBOL_GPL(kvm_set_memory_region); static int kvm_vm_ioctl_set_memory_region(struct kvm *kvm, - struct kvm_userspace_memory_region *mem) + struct kvm_userspace_memory_region2 *mem) { if ((u16)mem->slot >= KVM_USER_MEM_SLOTS) return -EINVAL; @@ -4559,6 +4559,7 @@ static int kvm_vm_ioctl_check_extension_generic(struct kvm *kvm, long arg) { switch (arg) { case KVM_CAP_USER_MEMORY: + case KVM_CAP_USER_MEMORY2: case KVM_CAP_DESTROY_MEMORY_REGION_WORKS: case KVM_CAP_JOIN_MEMORY_REGIONS_WORKS: case KVM_CAP_INTERNAL_ERROR_DATA: @@ -4814,6 +4815,14 @@ static int kvm_vm_ioctl_get_stats_fd(struct kvm *kvm) return fd; } +#define SANITY_CHECK_MEM_REGION_FIELD(field) \ +do { \ + BUILD_BUG_ON(offsetof(struct kvm_userspace_memory_region, field) != \ + offsetof(struct kvm_userspace_memory_region2, field)); \ + BUILD_BUG_ON(sizeof_field(struct kvm_userspace_memory_region, field) != \ + sizeof_field(struct kvm_userspace_memory_region2, field)); \ +} while (0) + static long kvm_vm_ioctl(struct file *filp, unsigned int ioctl, unsigned long arg) { @@ -4836,15 +4845,28 @@ static long kvm_vm_ioctl(struct file *filp, r = kvm_vm_ioctl_enable_cap_generic(kvm, &cap); break; } + case KVM_SET_USER_MEMORY_REGION2: case KVM_SET_USER_MEMORY_REGION: { - struct kvm_userspace_memory_region kvm_userspace_mem; + struct kvm_userspace_memory_region2 mem; + unsigned long size; + + if (ioctl == KVM_SET_USER_MEMORY_REGION) + size = sizeof(struct kvm_userspace_memory_region); + else + size = sizeof(struct kvm_userspace_memory_region2); + + /* Ensure the common parts of the two structs are identical. */ + SANITY_CHECK_MEM_REGION_FIELD(slot); + SANITY_CHECK_MEM_REGION_FIELD(flags); + SANITY_CHECK_MEM_REGION_FIELD(guest_phys_addr); + SANITY_CHECK_MEM_REGION_FIELD(memory_size); + SANITY_CHECK_MEM_REGION_FIELD(userspace_addr); r = -EFAULT; - if (copy_from_user(&kvm_userspace_mem, argp, - sizeof(kvm_userspace_mem))) + if (copy_from_user(&mem, argp, size)) goto out; - r = kvm_vm_ioctl_set_memory_region(kvm, &kvm_userspace_mem); + r = kvm_vm_ioctl_set_memory_region(kvm, &mem); break; } case KVM_GET_DIRTY_LOG: {