From patchwork Mon Mar 3 13:30:07 2025 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Nikita Kalyazin X-Patchwork-Id: 13998841 Received: from smtp-fw-9106.amazon.com (smtp-fw-9106.amazon.com [207.171.188.206]) (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 B72541F0E4F; Mon, 3 Mar 2025 13:30:38 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.client-ip=207.171.188.206 ARC-Seal: i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1741008640; cv=none; b=N9QzMbpi8elQ2P33FNtRqZyn3gIwt1RR0RrkmcfQMFErrd8qoVvVWUXkED4qwEM5kZlW//34INcejG1R3H29Ky9h7Wi51wTM4AUQ0XRTMsKNhljQo1ox5aSHKwSWDxS+T1v+jT1wqaAKN0tGzfydOkYyjlo4jGp+WC4w2Y1iRfs= ARC-Message-Signature: i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1741008640; c=relaxed/simple; bh=n+gAmjIUKvZXwsygtp1toh0bKCFMgv5xeKg/NqtjJj0=; h=From:To:CC:Subject:Date:Message-ID:In-Reply-To:References: MIME-Version:Content-Type; b=AIbmkx9Rm27AlQDzWN069zEbADKaMXr0rkkRqk3Lq59y6rwHHWivfKgZgdP5ofu76snNurbYnpHG/SpAW24YI19/VrdBQzgN2RuQobO8HA3IMPgz9vy1Xv+T0wWDxoU51RykWmfdbQj6tgHZSPTLbouPYUOfPH746oLrc1lG/G4= ARC-Authentication-Results: i=1; smtp.subspace.kernel.org; dmarc=pass (p=quarantine dis=none) header.from=amazon.com; spf=pass smtp.mailfrom=amazon.co.uk; dkim=pass (1024-bit key) header.d=amazon.com header.i=@amazon.com header.b=gorIPrQP; arc=none smtp.client-ip=207.171.188.206 Authentication-Results: smtp.subspace.kernel.org; dmarc=pass (p=quarantine dis=none) header.from=amazon.com Authentication-Results: smtp.subspace.kernel.org; spf=pass smtp.mailfrom=amazon.co.uk Authentication-Results: smtp.subspace.kernel.org; dkim=pass (1024-bit key) header.d=amazon.com header.i=@amazon.com header.b="gorIPrQP" DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=amazon.com; i=@amazon.com; q=dns/txt; s=amazon201209; t=1741008639; x=1772544639; h=from:to:cc:subject:date:message-id:in-reply-to: references:mime-version:content-transfer-encoding; bh=bUaunioKjZGZ2DQ4BkT3SKTdDYEcp1DDV2tTW0nbWvg=; b=gorIPrQPwRxmYY+/UV9nU64fuxRC7+9ByaJCqt2211kC0TpHdXmM6cHD 7VGhuqOgyjBcfsoQLGxuAkT1VIsC9is17yJotMRSF08vYTpNWNFhGCFqn RVUAnAntPEHDZAY2h+lYCOyNzXphiVaP+uKbi9xBLfLMl2EQjcu7S/7Nk 0=; X-IronPort-AV: E=Sophos;i="6.13,329,1732579200"; d="scan'208";a="803691335" Received: from pdx4-co-svc-p1-lb2-vlan2.amazon.com (HELO smtpout.prod.us-west-2.prod.farcaster.email.amazon.dev) ([10.25.36.210]) by smtp-border-fw-9106.sea19.amazon.com with ESMTP/TLS/ECDHE-RSA-AES256-GCM-SHA384; 03 Mar 2025 13:30:34 +0000 Received: from EX19MTAUWA002.ant.amazon.com [10.0.7.35:49609] by smtpin.naws.us-west-2.prod.farcaster.email.amazon.dev [10.0.21.102:2525] with esmtp (Farcaster) id 568d5078-4118-4f5e-91c9-1ef7962d1e6b; Mon, 3 Mar 2025 13:30:32 +0000 (UTC) X-Farcaster-Flow-ID: 568d5078-4118-4f5e-91c9-1ef7962d1e6b Received: from EX19D003UWB004.ant.amazon.com (10.13.138.24) by EX19MTAUWA002.ant.amazon.com (10.250.64.202) with Microsoft SMTP Server (version=TLS1_2, cipher=TLS_ECDHE_RSA_WITH_AES_128_CBC_SHA) id 15.2.1544.14; Mon, 3 Mar 2025 13:30:29 +0000 Received: from EX19MTAUWA001.ant.amazon.com (10.250.64.204) by EX19D003UWB004.ant.amazon.com (10.13.138.24) with Microsoft SMTP Server (version=TLS1_2, cipher=TLS_ECDHE_RSA_WITH_AES_128_CBC_SHA) id 15.2.1544.14; Mon, 3 Mar 2025 13:30:29 +0000 Received: from email-imr-corp-prod-pdx-all-2c-c4413280.us-west-2.amazon.com (10.25.36.214) by mail-relay.amazon.com (10.250.64.204) with Microsoft SMTP Server (version=TLS1_2, cipher=TLS_ECDHE_RSA_WITH_AES_128_CBC_SHA) id 15.2.1544.14 via Frontend Transport; Mon, 3 Mar 2025 13:30:29 +0000 Received: from dev-dsk-kalyazin-1a-a12e27e2.eu-west-1.amazon.com (dev-dsk-kalyazin-1a-a12e27e2.eu-west-1.amazon.com [172.19.103.116]) by email-imr-corp-prod-pdx-all-2c-c4413280.us-west-2.amazon.com (Postfix) with ESMTPS id C461CA039C; Mon, 3 Mar 2025 13:30:26 +0000 (UTC) From: Nikita Kalyazin To: , , CC: , , , , , , , , , , , , , , , , Subject: [RFC PATCH 1/5] KVM: guest_memfd: add kvm_gmem_vma_is_gmem Date: Mon, 3 Mar 2025 13:30:07 +0000 Message-ID: <20250303133011.44095-2-kalyazin@amazon.com> X-Mailer: git-send-email 2.47.1 In-Reply-To: <20250303133011.44095-1-kalyazin@amazon.com> References: <20250303133011.44095-1-kalyazin@amazon.com> Precedence: bulk X-Mailing-List: linux-kselftest@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 It will be used to distinguish the vma type in userfaultfd code. This likely needs to be done in the guestmem library. Signed-off-by: Nikita Kalyazin --- virt/kvm/guest_memfd.c | 5 +++++ virt/kvm/kvm_mm.h | 1 + 2 files changed, 6 insertions(+) diff --git a/virt/kvm/guest_memfd.c b/virt/kvm/guest_memfd.c index f93fe5835173..af825f7494ea 100644 --- a/virt/kvm/guest_memfd.c +++ b/virt/kvm/guest_memfd.c @@ -500,6 +500,11 @@ static ssize_t kvm_kmem_gmem_write(struct file *file, const char __user *buf, return ret && start == (*offset >> PAGE_SHIFT) ? ret : *offset - (start << PAGE_SHIFT); } + +bool kvm_gmem_vma_is_gmem(struct vm_area_struct *vma) +{ + return vma->vm_ops == &kvm_gmem_vm_ops; +} #endif /* CONFIG_KVM_GMEM_SHARED_MEM */ static struct file_operations kvm_gmem_fops = { diff --git a/virt/kvm/kvm_mm.h b/virt/kvm/kvm_mm.h index acef3f5c582a..09fcdf18a072 100644 --- a/virt/kvm/kvm_mm.h +++ b/virt/kvm/kvm_mm.h @@ -73,6 +73,7 @@ int kvm_gmem_create(struct kvm *kvm, struct kvm_create_guest_memfd *args); int kvm_gmem_bind(struct kvm *kvm, struct kvm_memory_slot *slot, unsigned int fd, loff_t offset); void kvm_gmem_unbind(struct kvm_memory_slot *slot); +bool kvm_gmem_vma_is_gmem(struct vm_area_struct *vma); #else static inline void kvm_gmem_init(struct module *module) { From patchwork Mon Mar 3 13:30:08 2025 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Nikita Kalyazin X-Patchwork-Id: 13998842 Received: from smtp-fw-6001.amazon.com (smtp-fw-6001.amazon.com [52.95.48.154]) (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 4DCFF213E88; Mon, 3 Mar 2025 13:30:49 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.client-ip=52.95.48.154 ARC-Seal: i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1741008652; cv=none; b=txl/TsypPzv5HcxiVFi32CLVXadnHJrP6sPl/pkTw/7W7/0nY3Gb4hTc9a1hh/4NlL/mGlbGjaiCaA3d9fbL3pIwnfEedat+7OSAUdbTxaP1blj6pfI/6EWqwF5oQwsOasyDq+g1WSUNX5jSis3W+RNDKnFLlE/EBcdeJP5HB2g= ARC-Message-Signature: i=1; a=rsa-sha256; d=subspace.kernel.org; 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Mon, 3 Mar 2025 13:30:42 +0000 Received: from EX19MTAUEA001.ant.amazon.com (10.252.134.203) by EX19D004EUA003.ant.amazon.com (10.252.50.230) with Microsoft SMTP Server (version=TLS1_2, cipher=TLS_ECDHE_RSA_WITH_AES_128_CBC_SHA) id 15.2.1544.14; Mon, 3 Mar 2025 13:30:41 +0000 Received: from email-imr-corp-prod-iad-1box-1a-9bbde7a3.us-east-1.amazon.com (10.43.8.2) by mail-relay.amazon.com (10.252.134.102) with Microsoft SMTP Server (version=TLS1_2, cipher=TLS_ECDHE_RSA_WITH_AES_128_CBC_SHA) id 15.2.1544.14 via Frontend Transport; Mon, 3 Mar 2025 13:30:41 +0000 Received: from dev-dsk-kalyazin-1a-a12e27e2.eu-west-1.amazon.com (dev-dsk-kalyazin-1a-a12e27e2.eu-west-1.amazon.com [172.19.103.116]) by email-imr-corp-prod-iad-1box-1a-9bbde7a3.us-east-1.amazon.com (Postfix) with ESMTPS id 3176540617; Mon, 3 Mar 2025 13:30:40 +0000 (UTC) From: Nikita Kalyazin To: , , CC: , , , , , , , , , , , , , , , , Subject: [RFC PATCH 2/5] KVM: guest_memfd: add support for uffd missing Date: Mon, 3 Mar 2025 13:30:08 +0000 Message-ID: <20250303133011.44095-3-kalyazin@amazon.com> X-Mailer: git-send-email 2.47.1 In-Reply-To: <20250303133011.44095-1-kalyazin@amazon.com> References: <20250303133011.44095-1-kalyazin@amazon.com> Precedence: bulk X-Mailing-List: linux-kselftest@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 Add support for sending a pagefault event if userfaultfd is registered. Only page missing event is currently supported. Signed-off-by: Nikita Kalyazin --- virt/kvm/guest_memfd.c | 12 +++++++++++- 1 file changed, 11 insertions(+), 1 deletion(-) diff --git a/virt/kvm/guest_memfd.c b/virt/kvm/guest_memfd.c index af825f7494ea..358c3776ed66 100644 --- a/virt/kvm/guest_memfd.c +++ b/virt/kvm/guest_memfd.c @@ -4,6 +4,9 @@ #include #include #include +#ifdef CONFIG_KVM_PRIVATE_MEM +#include +#endif /* CONFIG_KVM_PRIVATE_MEM */ #include "kvm_mm.h" @@ -332,9 +335,16 @@ static vm_fault_t kvm_gmem_fault(struct vm_fault *vmf) struct folio *folio; vm_fault_t ret = VM_FAULT_LOCKED; + folio = filemap_get_entry(inode->i_mapping, vmf->pgoff); + if (!folio && userfaultfd_missing(vmf->vma)) + return handle_userfault(vmf, VM_UFFD_MISSING); + if (folio) + folio_lock(folio); + filemap_invalidate_lock_shared(inode->i_mapping); - folio = kvm_gmem_get_folio(inode, vmf->pgoff); + if (!folio) + folio = kvm_gmem_get_folio(inode, vmf->pgoff); if (IS_ERR(folio)) { switch (PTR_ERR(folio)) { case -EAGAIN: From patchwork Mon Mar 3 13:30:09 2025 Content-Type: text/plain; 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Mon, 3 Mar 2025 13:30:54 +0000 Received: from EX19MTAUWC002.ant.amazon.com (10.250.64.143) by EX19D020UWC002.ant.amazon.com (10.13.138.147) with Microsoft SMTP Server (version=TLS1_2, cipher=TLS_ECDHE_RSA_WITH_AES_128_CBC_SHA) id 15.2.1544.14; Mon, 3 Mar 2025 13:30:54 +0000 Received: from email-imr-corp-prod-iad-all-1b-8410187a.us-east-1.amazon.com (10.25.36.210) by mail-relay.amazon.com (10.250.64.149) with Microsoft SMTP Server (version=TLS1_2, cipher=TLS_ECDHE_RSA_WITH_AES_128_CBC_SHA) id 15.2.1544.14 via Frontend Transport; Mon, 3 Mar 2025 13:30:54 +0000 Received: from dev-dsk-kalyazin-1a-a12e27e2.eu-west-1.amazon.com (dev-dsk-kalyazin-1a-a12e27e2.eu-west-1.amazon.com [172.19.103.116]) by email-imr-corp-prod-iad-all-1b-8410187a.us-east-1.amazon.com (Postfix) with ESMTPS id 77107406A9; Mon, 3 Mar 2025 13:30:52 +0000 (UTC) From: Nikita Kalyazin To: , , CC: , , , , , , , , , , , , , , , , Subject: [RFC PATCH 3/5] mm: userfaultfd: allow to register userfaultfd for guest_memfd Date: Mon, 3 Mar 2025 13:30:09 +0000 Message-ID: <20250303133011.44095-4-kalyazin@amazon.com> X-Mailer: git-send-email 2.47.1 In-Reply-To: <20250303133011.44095-1-kalyazin@amazon.com> References: <20250303133011.44095-1-kalyazin@amazon.com> Precedence: bulk X-Mailing-List: linux-kselftest@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 Signed-off-by: Nikita Kalyazin --- include/linux/userfaultfd_k.h | 9 +++++++++ 1 file changed, 9 insertions(+) diff --git a/include/linux/userfaultfd_k.h b/include/linux/userfaultfd_k.h index 75342022d144..440d38903359 100644 --- a/include/linux/userfaultfd_k.h +++ b/include/linux/userfaultfd_k.h @@ -20,6 +20,10 @@ #include #include +#ifdef CONFIG_KVM_PRIVATE_MEM +bool kvm_gmem_vma_is_gmem(struct vm_area_struct *vma); +#endif + /* The set of all possible UFFD-related VM flags. */ #define __VM_UFFD_FLAGS (VM_UFFD_MISSING | VM_UFFD_WP | VM_UFFD_MINOR) @@ -242,6 +246,11 @@ static inline bool vma_can_userfault(struct vm_area_struct *vma, return false; #endif +#ifdef CONFIG_KVM_PRIVATE_MEM + if (kvm_gmem_vma_is_gmem(vma)) + return true; +#endif + /* By default, allow any of anon|shmem|hugetlb */ return vma_is_anonymous(vma) || is_vm_hugetlb_page(vma) || vma_is_shmem(vma); From patchwork Mon Mar 3 13:30:10 2025 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Nikita Kalyazin X-Patchwork-Id: 13998844 Received: from smtp-fw-80008.amazon.com (smtp-fw-80008.amazon.com [99.78.197.219]) (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 50F80211491; Mon, 3 Mar 2025 13:31:20 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.client-ip=99.78.197.219 ARC-Seal: i=1; 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Mon, 3 Mar 2025 13:31:07 +0000 Received: from dev-dsk-kalyazin-1a-a12e27e2.eu-west-1.amazon.com (dev-dsk-kalyazin-1a-a12e27e2.eu-west-1.amazon.com [172.19.103.116]) by email-imr-corp-prod-pdx-all-2c-785684ef.us-west-2.amazon.com (Postfix) with ESMTPS id 27701A1025; Mon, 3 Mar 2025 13:31:05 +0000 (UTC) From: Nikita Kalyazin To: , , CC: , , , , , , , , , , , , , , , , Subject: [RFC PATCH 4/5] mm: userfaultfd: support continue for guest_memfd Date: Mon, 3 Mar 2025 13:30:10 +0000 Message-ID: <20250303133011.44095-5-kalyazin@amazon.com> X-Mailer: git-send-email 2.47.1 In-Reply-To: <20250303133011.44095-1-kalyazin@amazon.com> References: <20250303133011.44095-1-kalyazin@amazon.com> Precedence: bulk X-Mailing-List: linux-kselftest@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 When userspace receives a page missing event, it is supposed to populate the missing page in guest_memfd pagecache via the write syscall and unblock the faulting process via UFFDIO_CONTINUE. Signed-off-by: Nikita Kalyazin --- mm/userfaultfd.c | 23 ++++++++++++++++++++++- 1 file changed, 22 insertions(+), 1 deletion(-) diff --git a/mm/userfaultfd.c b/mm/userfaultfd.c index af3dfc3633db..aaff66a7f15b 100644 --- a/mm/userfaultfd.c +++ b/mm/userfaultfd.c @@ -19,6 +19,10 @@ #include #include "internal.h" +#ifdef CONFIG_KVM_PRIVATE_MEM +bool kvm_gmem_vma_is_gmem(struct vm_area_struct *vma); +#endif + static __always_inline bool validate_dst_vma(struct vm_area_struct *dst_vma, unsigned long dst_end) { @@ -391,6 +395,16 @@ static int mfill_atomic_pte_continue(pmd_t *dst_pmd, struct page *page; int ret; +#ifdef CONFIG_KVM_PRIVATE_MEM + if (kvm_gmem_vma_is_gmem(dst_vma)) { + ret = 0; + folio = filemap_get_entry(inode->i_mapping, pgoff); + if (IS_ERR(folio)) + ret = PTR_ERR(folio); + else + folio_lock(folio); + } else +#endif ret = shmem_get_folio(inode, pgoff, 0, &folio, SGP_NOALLOC); /* Our caller expects us to return -EFAULT if we failed to find folio */ if (ret == -ENOENT) @@ -769,9 +783,16 @@ static __always_inline ssize_t mfill_atomic(struct userfaultfd_ctx *ctx, return mfill_atomic_hugetlb(ctx, dst_vma, dst_start, src_start, len, flags); 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Mon, 3 Mar 2025 13:31:18 +0000 (UTC) From: Nikita Kalyazin To: , , CC: , , , , , , , , , , , , , , , , Subject: [RFC PATCH 5/5] KVM: selftests: add uffd missing test for guest_memfd Date: Mon, 3 Mar 2025 13:30:11 +0000 Message-ID: <20250303133011.44095-6-kalyazin@amazon.com> X-Mailer: git-send-email 2.47.1 In-Reply-To: <20250303133011.44095-1-kalyazin@amazon.com> References: <20250303133011.44095-1-kalyazin@amazon.com> Precedence: bulk X-Mailing-List: linux-kselftest@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 The test demonstrates how a page missing event can be resolved via write syscall followed by UFFDIO_CONTINUE ioctl. Signed-off-by: Nikita Kalyazin --- .../testing/selftests/kvm/guest_memfd_test.c | 88 +++++++++++++++++++ 1 file changed, 88 insertions(+) diff --git a/tools/testing/selftests/kvm/guest_memfd_test.c b/tools/testing/selftests/kvm/guest_memfd_test.c index b07221aa54c9..aea0e8627981 100644 --- a/tools/testing/selftests/kvm/guest_memfd_test.c +++ b/tools/testing/selftests/kvm/guest_memfd_test.c @@ -10,12 +10,16 @@ #include #include #include +#include #include #include +#include #include #include #include +#include +#include #include "kvm_util.h" #include "test_util.h" @@ -278,6 +282,88 @@ static void test_create_guest_memfd_multiple(struct kvm_vm *vm) close(fd1); } +struct fault_args { + char *addr; + volatile char value; +}; + +static void *fault_thread_fn(void *arg) +{ + struct fault_args *args = arg; + + /* Trigger page fault */ + args->value = *args->addr; + return NULL; +} + +static void test_uffd_missing(int fd, size_t page_size, size_t total_size) +{ + struct uffdio_register uffd_reg; + struct uffdio_continue uffd_cont; + struct uffd_msg msg; + struct fault_args args; + pthread_t fault_thread; + void *mem, *buf = NULL; + int uffd, ret; + off_t offset = page_size; + void *fault_addr; + + ret = posix_memalign(&buf, page_size, total_size); + TEST_ASSERT_EQ(ret, 0); + + uffd = syscall(__NR_userfaultfd, O_CLOEXEC); + TEST_ASSERT(uffd != -1, "userfaultfd creation should succeed"); + + struct uffdio_api uffdio_api = { + .api = UFFD_API, + .features = UFFD_FEATURE_MISSING_SHMEM, + }; + ret = ioctl(uffd, UFFDIO_API, &uffdio_api); + TEST_ASSERT(ret != -1, "ioctl(UFFDIO_API) should succeed"); + + mem = mmap(NULL, total_size, PROT_READ | PROT_WRITE, MAP_SHARED, fd, 0); + TEST_ASSERT(mem != MAP_FAILED, "mmap should succeed"); + + uffd_reg.range.start = (unsigned long)mem; + uffd_reg.range.len = total_size; + uffd_reg.mode = UFFDIO_REGISTER_MODE_MISSING; + ret = ioctl(uffd, UFFDIO_REGISTER, &uffd_reg); + TEST_ASSERT(ret != -1, "ioctl(UFFDIO_REGISTER) should succeed"); + + ret = fallocate(fd, FALLOC_FL_KEEP_SIZE | FALLOC_FL_PUNCH_HOLE, + offset, page_size); + TEST_ASSERT(!ret, "fallocate(PUNCH_HOLE) should succeed"); + + fault_addr = mem + offset; + args.addr = fault_addr; + + ret = pthread_create(&fault_thread, NULL, fault_thread_fn, &args); + TEST_ASSERT(ret == 0, "pthread_create should succeed"); + + ret = read(uffd, &msg, sizeof(msg)); + TEST_ASSERT(ret != -1, "read from userfaultfd should succeed"); + TEST_ASSERT(msg.event == UFFD_EVENT_PAGEFAULT, "event type should be pagefault"); + TEST_ASSERT((void *)(msg.arg.pagefault.address & ~(page_size - 1)) == fault_addr, + "pagefault should occur at expected address"); + + ret = pwrite(fd, buf + offset, page_size, offset); + TEST_ASSERT(ret == page_size, "write should succeed"); + + uffd_cont.range.start = (unsigned long)fault_addr; + uffd_cont.range.len = page_size; + uffd_cont.mode = 0; + ret = ioctl(uffd, UFFDIO_CONTINUE, &uffd_cont); + TEST_ASSERT(ret != -1, "ioctl(UFFDIO_CONTINUE) should succeed"); + + ret = pthread_join(fault_thread, NULL); + TEST_ASSERT(ret == 0, "pthread_join should succeed"); + + ret = munmap(mem, total_size); + TEST_ASSERT(!ret, "munmap should succeed"); + free(buf); + close(uffd); +} + unsigned long get_shared_type(void) { #ifdef __x86_64__ @@ -316,6 +402,8 @@ void test_vm_type(unsigned long type, bool is_shared) test_file_size(fd, page_size, total_size); test_fallocate(fd, page_size, total_size); test_invalid_punch_hole(fd, page_size, total_size); + if (is_shared) + test_uffd_missing(fd, page_size, total_size); close(fd); kvm_vm_release(vm);