From nobody Wed Feb 11 00:59:49 2026 Delivered-To: importer@patchew.org Authentication-Results: mx.zohomail.com; spf=pass (zohomail.com: domain of gnu.org designates 209.51.188.17 as permitted sender) smtp.mailfrom=qemu-devel-bounces+importer=patchew.org@nongnu.org Return-Path: Received: from lists.gnu.org (lists.gnu.org [209.51.188.17]) by mx.zohomail.com with SMTPS id 1763781662792942.1915923910798; Fri, 21 Nov 2025 19:21:02 -0800 (PST) Received: from localhost ([::1] helo=lists1p.gnu.org) by lists.gnu.org with esmtp (Exim 4.90_1) (envelope-from ) id 1vMcxW-0002d8-De; Fri, 21 Nov 2025 21:02:43 -0500 Received: from eggs.gnu.org ([2001:470:142:3::10]) by lists.gnu.org with esmtps (TLS1.2:ECDHE_RSA_AES_256_GCM_SHA384:256) (Exim 4.90_1) (envelope-from ) id 1vMc3c-0002li-BU; Fri, 21 Nov 2025 20:04:56 -0500 Received: from isrv.corpit.ru ([212.248.84.144]) by eggs.gnu.org with esmtps (TLS1.2:ECDHE_RSA_AES_256_GCM_SHA384:256) (Exim 4.90_1) (envelope-from ) id 1vMc1Z-0002f2-Q9; Fri, 21 Nov 2025 20:04:52 -0500 Received: from tsrv.corpit.ru (tsrv.tls.msk.ru [192.168.177.2]) by isrv.corpit.ru (Postfix) with ESMTP id EFDD516CA61; Fri, 21 Nov 2025 21:44:24 +0300 (MSK) Received: from think4mjt.tls.msk.ru (mjtthink.wg.tls.msk.ru [192.168.177.146]) by tsrv.corpit.ru (Postfix) with ESMTP id A60C9321C9D; Fri, 21 Nov 2025 21:44:33 +0300 (MSK) From: Michael Tokarev To: qemu-devel@nongnu.org Cc: qemu-stable@nongnu.org, Xiaoyao Li , Stefano Garzarella , David Hildenbrand , Peter Xu , Michael Tokarev Subject: [Stable-10.0.7 38/81] hostmem/shm: Allow shm memory backend serve as shared memory for coco-VMs Date: Fri, 21 Nov 2025 21:43:37 +0300 Message-ID: <20251121184424.1137669-38-mjt@tls.msk.ru> X-Mailer: git-send-email 2.47.3 In-Reply-To: References: MIME-Version: 1.0 Content-Transfer-Encoding: quoted-printable Received-SPF: pass (zohomail.com: domain of gnu.org designates 209.51.188.17 as permitted sender) client-ip=209.51.188.17; envelope-from=qemu-devel-bounces+importer=patchew.org@nongnu.org; helo=lists.gnu.org; Received-SPF: pass client-ip=212.248.84.144; envelope-from=mjt@tls.msk.ru; helo=isrv.corpit.ru X-BeenThere: qemu-devel@nongnu.org X-Mailman-Version: 2.1.29 Precedence: list List-Id: List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Errors-To: qemu-devel-bounces+importer=patchew.org@nongnu.org Sender: qemu-devel-bounces+importer=patchew.org@nongnu.org X-ZM-MESSAGEID: 1763781665336018900 Content-Type: text/plain; charset="utf-8" From: Xiaoyao Li shm can surely serve as the shared memory for coco-VMs. But currently it doesn't check the backend->guest_memfd to pass down the RAM_GUEST_MEMFD flag. It leads to failure when creating coco-VMs (e.g., TDX guest) which require private mmeory. Set and pass down RAM_GUEST_MEMFD when backend->guest_memfd is true, to allow shm memory backend serve as shared memory for coco-VMs. Cc: Stefano Garzarella Cc: qemu-stable Signed-off-by: Xiaoyao Li Acked-by: David Hildenbrand Acked-by: Stefano Garzarella Link: https://lore.kernel.org/r/20250721065220.895606-1-xiaoyao.li@intel.com Signed-off-by: Peter Xu (cherry picked from commit 75e2cb144191ecdbba87cfea3608cdc0664c8142) Signed-off-by: Michael Tokarev diff --git a/backends/hostmem-shm.c b/backends/hostmem-shm.c index f67ad2740b..befa0020b7 100644 --- a/backends/hostmem-shm.c +++ b/backends/hostmem-shm.c @@ -54,6 +54,7 @@ have_fd: /* Let's do the same as memory-backend-ram,share=3Don would do. */ ram_flags =3D RAM_SHARED; ram_flags |=3D backend->reserve ? 0 : RAM_NORESERVE; + ram_flags |=3D backend->guest_memfd ? RAM_GUEST_MEMFD : 0; =20 return memory_region_init_ram_from_fd(&backend->mr, OBJECT(backend), backend_name, backend->size, --=20 2.47.3