From nobody Tue Nov 26 14:22:22 2024 Delivered-To: importer@patchew.org Authentication-Results: mx.zohomail.com; dkim=pass; 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; dmarc=pass(p=none dis=none) header.from=redhat.com ARC-Seal: i=1; a=rsa-sha256; t=1706910894; cv=none; d=zohomail.com; s=zohoarc; b=cMXKh00Dt1lcD2i67SrdVWn4RNP9vbdXbxeLxBnNEfb/wOeiX+jD4fP0Y3/noN0GYq0vz220r00ODpLNqn/5lowb8mBXV/JzYwyiuNHaHwR3nsyxJtgeXzlo76DwJLW7C+JIOuqNPHK1Pte0sinnTUUPYTm0PX+LcEw1ta6EpGk= ARC-Message-Signature: i=1; a=rsa-sha256; c=relaxed/relaxed; d=zohomail.com; s=zohoarc; t=1706910894; h=Content-Transfer-Encoding:Cc:Cc:Date:Date:From:From:In-Reply-To:List-Subscribe:List-Post:List-Id:List-Archive:List-Help:List-Unsubscribe:MIME-Version:Message-ID:References:Sender:Subject:Subject:To:To:Message-Id:Reply-To; bh=OdNqjIdTvGgL2rzqx1u7F6VWnSUR37k3K9wxCLfN5WQ=; b=M6FuJHjdjiJZmBXfKy5dypvoAPVw58B2913Ya1bOzMf8lK4Qc+ex7poL0G1puQcLNHBDkBP4lk76BVz9oQUS4ZtcFK87ik31Q3wsYzyTxuwVmqC4Qc6oKxRN6omakvsWeN54Ov4aR7dBxHGaDY7jXFFrQmqPwVkplNEw+Tmf0II= ARC-Authentication-Results: i=1; mx.zohomail.com; dkim=pass; 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; dmarc=pass header.from= (p=none dis=none) Return-Path: Received: from lists.gnu.org (lists.gnu.org [209.51.188.17]) by mx.zohomail.com with SMTPS id 1706910894911804.2227062055362; Fri, 2 Feb 2024 13:54:54 -0800 (PST) Received: from localhost ([::1] helo=lists1p.gnu.org) by lists.gnu.org with esmtp (Exim 4.90_1) (envelope-from ) id 1rW1UM-0000CS-RB; Fri, 02 Feb 2024 16:54:22 -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 1rW1UJ-0008Oo-MK for qemu-devel@nongnu.org; Fri, 02 Feb 2024 16:54:19 -0500 Received: from us-smtp-delivery-124.mimecast.com ([170.10.129.124]) by eggs.gnu.org with esmtps (TLS1.2:ECDHE_RSA_AES_256_GCM_SHA384:256) (Exim 4.90_1) (envelope-from ) id 1rW1UI-0004vC-29 for qemu-devel@nongnu.org; Fri, 02 Feb 2024 16:54:19 -0500 Received: from mimecast-mx02.redhat.com (mx-ext.redhat.com [66.187.233.73]) by relay.mimecast.com with ESMTP with STARTTLS (version=TLSv1.3, cipher=TLS_AES_256_GCM_SHA384) id us-mta-227-M3N-RdjZOwGzC0RD1jkMuA-1; Fri, 02 Feb 2024 16:54:15 -0500 Received: from smtp.corp.redhat.com (int-mx06.intmail.prod.int.rdu2.redhat.com [10.11.54.6]) (using TLSv1.3 with cipher TLS_AES_256_GCM_SHA384 (256/256 bits) key-exchange X25519 server-signature RSA-PSS (2048 bits) server-digest SHA256) (No client certificate requested) by mimecast-mx02.redhat.com (Postfix) with ESMTPS id 651703C0ED44; Fri, 2 Feb 2024 21:54:15 +0000 (UTC) Received: from t14s.redhat.com (unknown [10.39.192.47]) by smtp.corp.redhat.com (Postfix) with ESMTP id 3CF402166B31; Fri, 2 Feb 2024 21:54:13 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=redhat.com; s=mimecast20190719; t=1706910857; h=from:from:reply-to:subject:subject:date:date:message-id:message-id: to:to:cc:cc:mime-version:mime-version: content-transfer-encoding:content-transfer-encoding: in-reply-to:in-reply-to:references:references; bh=OdNqjIdTvGgL2rzqx1u7F6VWnSUR37k3K9wxCLfN5WQ=; b=IECqDy7ZBCd0rH4inPNBo0aq04/X+IzsrFMqjVfPJgqTxswfw78Xmwr04bIwm4h+7giJ4d X9SeatH0WehLQ2Ld0knG0pla938hH8BCCc7TJoCKXflaSWn+ooXPX9t0EuKr/FQI27Mj3I EoVfzSuwqEsnzpeaLWp6FO7S0gixtE0= X-MC-Unique: M3N-RdjZOwGzC0RD1jkMuA-1 From: David Hildenbrand To: qemu-devel@nongnu.org Cc: David Hildenbrand , "Michael S . Tsirkin" , Jason Wang , Stefan Hajnoczi , Stefano Garzarella , Germano Veit Michel , Raphael Norwitz Subject: [PATCH v1 15/15] libvhost-user: Mark mmap'ed region memory as MADV_DONTDUMP Date: Fri, 2 Feb 2024 22:53:32 +0100 Message-ID: <20240202215332.118728-16-david@redhat.com> In-Reply-To: <20240202215332.118728-1-david@redhat.com> References: <20240202215332.118728-1-david@redhat.com> MIME-Version: 1.0 Content-Transfer-Encoding: quoted-printable X-Scanned-By: MIMEDefang 3.4.1 on 10.11.54.6 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=170.10.129.124; envelope-from=david@redhat.com; helo=us-smtp-delivery-124.mimecast.com X-Spam_score_int: -43 X-Spam_score: -4.4 X-Spam_bar: ---- X-Spam_report: (-4.4 / 5.0 requ) BAYES_00=-1.9, DKIMWL_WL_HIGH=-2.276, DKIM_SIGNED=0.1, DKIM_VALID=-0.1, DKIM_VALID_AU=-0.1, DKIM_VALID_EF=-0.1, RCVD_IN_DNSWL_NONE=-0.0001, RCVD_IN_MSPIKE_H2=-0.001, SPF_HELO_NONE=0.001, SPF_PASS=-0.001, T_SCC_BODY_TEXT_LINE=-0.01 autolearn=ham autolearn_force=no X-Spam_action: no action 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-ZohoMail-DKIM: pass (identity @redhat.com) X-ZM-MESSAGEID: 1706910896076100008 Content-Type: text/plain; charset="utf-8" We already use MADV_NORESERVE to deal with sparse memory regions. Let's also set madvise(MADV_DONTDUMP), otherwise a crash of the process can result in us allocating all memory in the mmap'ed region for dumping purposes. This change implies that the mmap'ed rings won't be included in a coredump. If ever required for debugging purposes, we could mark only the mapped rings MADV_DODUMP. Ignore errors during madvise() for now. Signed-off-by: David Hildenbrand Reviewed-by: Raphael Norwitz --- subprojects/libvhost-user/libvhost-user.c | 6 ++++++ 1 file changed, 6 insertions(+) diff --git a/subprojects/libvhost-user/libvhost-user.c b/subprojects/libvho= st-user/libvhost-user.c index 738e84ab63..26c289518c 100644 --- a/subprojects/libvhost-user/libvhost-user.c +++ b/subprojects/libvhost-user/libvhost-user.c @@ -458,6 +458,12 @@ _vu_add_mem_reg(VuDev *dev, VhostUserMemoryRegion *msg= _region, int fd) DPRINT(" mmap_addr: 0x%016"PRIx64"\n", (uint64_t)(uintptr_t)mmap_addr); =20 +#if defined(__linux__) + /* Don't include all guest memory in a coredump. */ + madvise(mmap_addr, msg_region->memory_size + mmap_offset, + MADV_DONTDUMP); +#endif + /* Shift all affected entries by 1 to open a hole at idx. */ r =3D &dev->regions[idx]; memmove(r + 1, r, sizeof(VuDevRegion) * (dev->nregions - idx)); --=20 2.43.0