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 A3E503CA4A0; Tue, 28 Apr 2026 23:25:20 +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=1777418720; cv=none; b=hKlIP6z8l/bRgJt4uSJDY9PnMutbiE0beAayj6TNru1Jpc4zzBtxQ29HGi1jjf2fMtuqbCJA+/0LbQEDSMhQaImY21wzP0Jk+LNax8B+a/cxnzMmYBsdB9YSOWEYsxPUBw2OSUfVEM8Glq31Y4LT9mVWamyH7Z3MtbAR5Vka+pk= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1777418720; c=relaxed/simple; bh=wdLoj8HH8Ns1xI8zoSpP1xSUU4YJ7JLqU9N7Wg1Hrz0=; h=From:Date:Subject:MIME-Version:Content-Type:Message-Id:References: In-Reply-To:To:Cc; b=NqljaZHyg7fQ6h5MuMx9A6nEKBZjbzHkUkumxU1OPWQDQN5evcrYo2JfGIXAy8axdPSnnnQh1RFSr/I9WIowzAmQ/YYF5E1YDIHC47AanXcru95EeL3H1HLRaFMEyG+hWowGO4izTKdYVEbuK5uzu2YOrCnIeU9/Tt3ZyG0J8J8= ARC-Authentication-Results:i=1; smtp.subspace.kernel.org; dkim=pass (2048-bit key) header.d=kernel.org header.i=@kernel.org header.b=VVOYp38t; 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="VVOYp38t" Received: by smtp.kernel.org (Postfix) with ESMTPS id 7ED6AC2BCFA; Tue, 28 Apr 2026 23:25:20 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=k20201202; t=1777418720; bh=wdLoj8HH8Ns1xI8zoSpP1xSUU4YJ7JLqU9N7Wg1Hrz0=; h=From:Date:Subject:References:In-Reply-To:To:Cc:Reply-To:From; b=VVOYp38tDjUKY+lrdJC7aR7qz8kMFuqNZpBLzDkfG6IRhjfGsPWMpGGOHl4z77Rk6 J3sdvSPB7VUnU3vCX73wAaYDp8rsUodfc5LsB5r3/xVF35wBkBwJcdV/6FQupgtdBG 9Dn2XHEnTEfFJwAhaB20qXDXWUib5ZRhAtXzht1S8HQQj30ZPQ/K4MpmejzrX631UB e4zHW2BxJtZii/IbBildVt5eTcQYlE1nc+mchzY3WalFToQBLRkP/W8Y3S9eP+ToWv F5tQ9t/R1HNRc7sW2MSpPYUGLV787DrXs0Phn0kbDwl+pyRiUZzDhVf81fSZbuAebl ifs0Ft1NbLapg== 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 7229AFF8875; Tue, 28 Apr 2026 23:25:20 +0000 (UTC) From: Ackerley Tng via B4 Relay Date: Tue, 28 Apr 2026 16:25:34 -0700 Subject: [PATCH RFC v5 39/53] KVM: selftests: Test that truncation does not change shared/private 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: <20260428-gmem-inplace-conversion-v5-39-d8608ccfca22@google.com> References: <20260428-gmem-inplace-conversion-v5-0-d8608ccfca22@google.com> In-Reply-To: <20260428-gmem-inplace-conversion-v5-0-d8608ccfca22@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, 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=1777418714; l=1978; i=ackerleytng@google.com; s=20260225; h=from:subject:message-id; bh=Bf9VYURnTgb4TwvCJyU5mwma0raoYBRglUIu1BddfsA=; b=Sy3fBvTvGT1l7P1754XNGwhnHr5V9qJNv9e3LC5taI2eQg7S9WzmF2LhNSMc6bbYXC5UjP7XV g61CrfU/Av3A6d5LctiXFLDMlkZ9ifHKNPN3O6xFeLM86WNKXhjnss1 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 Add a test to verify that deallocating a page in a guest memfd region via fallocate() with FALLOC_FL_PUNCH_HOLE does not alter the shared or private status of the corresponding memory range. When a page backing a guest memfd mapping is deallocated, e.g., by punching a hole or truncating the file, and then subsequently faulted back in, the new page must inherit the correct shared/private status tracked by guest_memfd. Signed-off-by: Ackerley Tng Co-developed-by: Sean Christopherson Signed-off-by: Sean Christopherson --- .../selftests/kvm/x86/guest_memfd_conversions_test.c | 14 ++++++++++++++ 1 file changed, 14 insertions(+) diff --git a/tools/testing/selftests/kvm/x86/guest_memfd_conversions_test.c b/tools/testing/selftests/kvm/x86/guest_memfd_conversions_test.c index 2312592c4076b..8dfbf3630cec2 100644 --- a/tools/testing/selftests/kvm/x86/guest_memfd_conversions_test.c +++ b/tools/testing/selftests/kvm/x86/guest_memfd_conversions_test.c @@ -10,6 +10,7 @@ #include #include "kvm_util.h" +#include "kvm_syscalls.h" #include "kselftest_harness.h" #include "test_util.h" #include "ucall_common.h" @@ -320,6 +321,19 @@ GMEM_CONVERSION_MULTIPAGE_TEST_INIT_SHARED(unallocated_folios, 8) test_convert_to_shared(t, i, 'B', 'C', 'D'); } +/* Truncation should not affect shared/private status. */ +GMEM_CONVERSION_TEST_INIT_SHARED(truncate) +{ + host_do_rmw(t->mem, 0, 0, 'A'); + kvm_fallocate(t->gmem_fd, FALLOC_FL_KEEP_SIZE | FALLOC_FL_PUNCH_HOLE, 0, page_size); + host_do_rmw(t->mem, 0, 0, 'A'); + + test_convert_to_private(t, 0, 'A', 'B'); + + kvm_fallocate(t->gmem_fd, FALLOC_FL_KEEP_SIZE | FALLOC_FL_PUNCH_HOLE, 0, page_size); + test_private(t, 0, 0, 'A'); +} + int main(int argc, char *argv[]) { TEST_REQUIRE(kvm_check_cap(KVM_CAP_VM_TYPES) & BIT(KVM_X86_SW_PROTECTED_VM)); -- 2.54.0.545.g6539524ca2-goog