From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: from mail.openvz.org (mail.openvz.org [69.168.225.77]) by lore.virtuozzo.com (Postfix) with ESMTPS id 139BF811BB for ; Thu, 5 Nov 2026 17:52:43 +0000 (UTC) Received: from mail.openvz.org (localhost [127.0.0.1]) by mail.openvz.org (8.14.4/8.14.4) with ESMTP id 6A5HpNDJ007455; Thu, 5 Nov 2026 20:51:24 +0300 DKIM-Filter: OpenDKIM Filter v2.11.0 mail.openvz.org 6A5HpNDJ007455 Authentication-Results: mail.openvz.org; dkim=fail reason="signature verification failed" (2048-bit key) header.d=virtuozzo.com header.i=@virtuozzo.com header.b="FRaaVmG3" Received: from mail-wr1-f72.google.com (mail-wr1-f72.google.com [209.85.221.72]) by mail.openvz.org (8.14.4/8.14.4) with ESMTP id 6A5HpMoH007447 (version=TLSv1/SSLv3 cipher=AES128-GCM-SHA256 bits=128 verify=FAIL) for ; Thu, 5 Nov 2026 20:51:22 +0300 DKIM-Filter: OpenDKIM Filter v2.11.0 mail.openvz.org 6A5HpMoH007447 Received: by mail-wr1-f72.google.com with SMTP id ffacd0b85a97d-4925ef75fc4so181533f8f.1 for ; Thu, 05 Nov 2026 09:51:22 -0800 (PST) X-Gm-Message-State: APuU4Z8XUZZQIVlCZ7HNs3NP0G33VDoYTnE3Q5UJlxU6Fj/OXrR15IpX 4ln9okHld0s/WdsFynddqrorOs1W+IEzzymERAigNOT9mR52ibg6J+CaaU75bAWVDLuZxbVTmwb ZTETtuxDFa5ogNaykeBFi41hIb86ho7FvHM8tyqTUhUFWSyqfv5Tg8Q== X-Gm-Gg: AYBFou03x9blr65C+Jubf/5bvmHTFGMlypb10N2gRfvQkhFzZm+MB72SW/GJTNPiUqw I+iUgX8ksThfORLjI0xymB7fRPME/yrWlmjc9zlyTECJ+eKZViH1O3T3MW+Rrc5t8kEK2evvD+k tYKoX3qX4it/AgwKap7EcVhOvpJR2+sxu8N20u9V1JN2NJpKIsqEUE3xR6wlgXc+ytgTEwThUkp 5vCtnZo8I/OUGNn+aKlN9aDCk1nvVF2WOqaycTVgsJbgkh5MCD9SQMckvFXg1zTG/o4giWv0gSM 0r3hq3wKgs6tg2VznLq5CUyF2vNqAQXXe87aUBjeiDL5JvagMwXyNoPd9t3i2fypi5O4CbW9Ffd m7jEEyvLJmnBFCJZd X-Received: by 2002:a05:6000:4908:b0:48e:68d5:818d with SMTP id ffacd0b85a97d-49274bc8392mr672763f8f.16.1793901081928; Thu, 05 Nov 2026 09:51:21 -0800 (PST) X-Received: by 2002:a05:6000:4908:b0:48e:68d5:818d with SMTP id ffacd0b85a97d-49274bc8392mr672735f8f.16.1793901081509; Thu, 05 Nov 2026 09:51:21 -0800 (PST) ARC-Seal: i=1; a=rsa-sha256; t=1793901081; cv=none; d=google.com; s=arc-20260327; b=jh2XGueF61X0ESrENMc0ZdnFJYLu9cbmMkaKN8kb1zHm5bGLg7hSYHjQJgSGpSgtx+ fKxPprURAWDtfzTkhW4AQbEOT6vulgxxnAwtADQ9Uh77VW4YixnLd+uOQPik0gRvhG00 IVAFx4EM7J7i2qDaMxLPVUr5V574NZ9CO1v2YQw7ZO52Lv13UlxhnBU4CP4JHo1P0TWS si6n1byAHJH69oVhVj1VYSEp8DtBaPvdBTWMg6/Tx4aKz6WhnoAov7sA4K/OidT7SenY OUGWbgc7EwZnJzOYYvprHzdChBvZhNizsYIuChtmkYJFlLsWmyLKIzF92s65aSCyG+zL zjVA== ARC-Message-Signature: i=1; a=rsa-sha256; c=relaxed/relaxed; d=google.com; s=arc-20260327; h=message-id:date:references:in-reply-to:cc:to:from:subject :content-transfer-encoding:mime-version:dkim-signature; bh=W9CP+E5pz6coxr03uQKhIIKYziHow8xuPQPsg+PTRjw=; fh=5AmFLEo6nHxL6WDW39LXC01IwU+CKjcYMpOuqqVTSIM=; b=cQqofmS646YLFcI2cFbhKNbcnSPVyGrzcTZobzGbyH+8LoaGbUxv/Lscdul/txvpTp 9DrrYKvceVcRpBwyDYt8ZO2n6aslqVa5OZixsXYbjI/+5Y+C7X9twLOb3Bqx+s0c65l+ rUT+AwChr7z09bhPJdenqxEBnp2oXxnZPwy/VY3HanRsF0PfVPams2tLIdDxho5zHQlS NObiDaBPMMMnvKVMcoQ52j55/Z6Fu5ucyLuGY+4y3qUo8P4UlOMkjAOAkmNMFpqdbWR6 vzOSYv4A0823wqnlLKL8xtakaNWTbrLZv9Lr5jd6mJY04ULmNiYmYp56KRAKZ0HJr36A 1WDg==; dara=google.com ARC-Authentication-Results: i=1; mx.google.com; dkim=pass header.i=@virtuozzo.com header.s=relay header.b=FRaaVmG3; spf=pass (google.com: domain of khorenko@virtuozzo.com designates 130.117.225.111 as permitted sender) smtp.mailfrom=khorenko@virtuozzo.com; dmarc=pass (p=QUARANTINE sp=QUARANTINE dis=NONE) header.from=virtuozzo.com Received: from relay.virtuozzo.com (relay.virtuozzo.com. [130.117.225.111]) by mx.google.com with ESMTPS id ffacd0b85a97d-48feee31705si12045345f8f.264.2026.11.05.09.51.21 for (version=TLS1_3 cipher=TLS_AES_256_GCM_SHA384 bits=256/256); Thu, 05 Nov 2026 09:51:21 -0800 (PST) Received-SPF: pass (google.com: domain of khorenko@virtuozzo.com designates 130.117.225.111 as permitted sender) client-ip=130.117.225.111; Authentication-Results: mx.google.com; dkim=pass header.i=@virtuozzo.com header.s=relay header.b=FRaaVmG3; spf=pass (google.com: domain of khorenko@virtuozzo.com designates 130.117.225.111 as permitted sender) smtp.mailfrom=khorenko@virtuozzo.com; dmarc=pass (p=QUARANTINE sp=QUARANTINE dis=NONE) header.from=virtuozzo.com DKIM-Signature: v=1; a=rsa-sha256; q=dns/txt; c=relaxed/relaxed; d=virtuozzo.com; s=relay; h=Message-Id:Date:From:Subject:Content-Type: MIME-Version; bh=W9CP+E5pz6coxr03uQKhIIKYziHow8xuPQPsg+PTRjw=; b=FRaaVmG33/TN +v1XzNEXs5L3oCJ7E1oSNMv+nbN2JMULsSW46UJY0j7b1RKQ5jV9mXcVLsby+8e70eLik81q6xNA+ CdJFR6cvKfaC1PsiEYD5amVOcvtgf0InhcBQ2mbB5ZfeyAqno5vIRukpGe1SV3dmt7s5dWT/dSuCJ KYCPMxnwKY9GlOZrGTEiCTdoWvbBraDe+5MfxLCjVa01swqqMdhVYZ1KGkue9zsHr16kzmDvSWQQt 24nRtutZtBeoRYQJUJqx9UxAv2F6bnLyyMehJ7pJ+ZDjmQ1enJDIrVq/L49hpViG863OHpzqavoR1 q8T/U1pGtuTWY+WpTmJ0rA==; Received: from ch-demo-asa.virtuozzo.com ([130.117.225.8] helo=f0.sw.ru) by relay.virtuozzo.com with esmtp (Exim 4.96) (envelope-from ) id 1xP1YQ-0069n4-1Z; Thu, 05 Nov 2026 18:51:18 +0100 MIME-Version: 1.0 From: Konstantin Khorenko To: Andrey Drobyshev In-Reply-To: <20261105141759.750676-1-andrey.drobyshev@virtuozzo.com> References: <20261105141759.750676-1-andrey.drobyshev@virtuozzo.com> Date: Thu, 05 Nov 2026 18:51:18 +0100 Message-Id: <179390107828.2925323.247920460637301249.b4-review@b4> X-Mailer: b4 0.16.0 X-Developer-Signature: v=1; a=openpgp-sha256; l=1300; i=khorenko@virtuozzo.com; h=from:subject:message-id; bh=zmbUnxBKwbq6KoO7Icda/L2Asf/n75mKLU1rguz9qR4=; b=owEBbQKS/ZANAwAKAVGWCkf5YVwqAcsmYgBq7MIYg+lCebIErJe8hwfprHuAxP7CRMlzb3nB3 toBxgfhJlGJAjMEAAEKAB0WIQRWD23IPcXT0GO9CCxRlgpH+WFcKgUCauzCGAAKCRBRlgpH+WFc Kq7zD/9N5JxSPSTGsaQp24+0uKCT9HiSppAr9ZXH9VEBSFA5/7PuLAw2A8ur+S2HNQ9tKMvVlz2 Kj63TJ+xwVaHje1M/aSnRG1Rca4+mH51gje97kWiGJpqkn66/te/ykjRpK+KINSJ1FC36R+tISq hqqAA6lWk1UPGLsdNLlieZZx4BZbc/Aedv4+W+7NkDCtf9RjIolm/Sy75ewXUHQhE+pbRKBleIh CkxSw7xwxRj9tKqhSx/ueCKwerEEDYs4fKXPbj462siKHDlMbY+cErsuVZ8qJjhnOpajH74wezT e25/pQVPz4J4QEqjK9X9wcmmLQXaEE7LIGLXaFc55rQYuQTRp4/x0PjCm59xI6ZI0G5todWrm/n 10v0/vE5LjBbaaOFWJsCztsLY648Qgjp/nETlo6UKSvRPsKfgFMF1t1E7UIGafK11zFhQVyZhHC POBeE0bKk1N8vEI/96bH6LjHYHdhNRm1QAtpCHoP0rwd20lyMhLUnc8nE+lmooJ1jrxVLR6bnhr 3tUgb1g+Rz3QUXFDyu3Mp2QXouUYYSHsF5npaCWhGQ/IrxqjeH+gsXz3xtv2zkIgwG0vQ0aYLru 8Pr75d6Q1tUeOgx+cxgFDgDLW5Mo3R3IS8uYr1kyFpO7KOyl1ZmZl9jElNL/7cSxsBkk0MJDxwv HHMg5RBTLm/5gKA== X-Developer-Key: i=khorenko@virtuozzo.com; a=openpgp; fpr=560F6DC83DC5D3D063BD082C51960A47F9615C2A X-OZ-Fwd: true Cc: devel@openvz.org Subject: Re: [Devel] [PATCH hci-8.1 v3 0/1] vfio: kvm reference leak on live update X-BeenThere: devel@openvz.org X-Mailman-Version: 2.1.12 Precedence: list List-Id: OpenVZ development List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Content-Type: text/plain; charset="us-ascii" Content-Transfer-Encoding: 7bit Sender: devel-bounces@openvz.org Errors-To: devel-bounces@openvz.org Applying with these fixes on my side: - commit message: KVMGT reads device->kvm while the guest runs too, not only in open_device() and at close; - struct vfio_device comment: the flag is for a driver that uses device->kvm while the device is open, not only in open_device(); - the comments before the kvm get in vfio_df_group_open() and vfio_df_ioctl_bind_iommufd(): the pointer is saved only when the driver set needs_kvm_ref. On Thu, 5 Nov 2026 16:17:58 +0200, Andrey Drobyshev wrote: > Andrey Drobyshev (1): > vfio: take the kvm reference only for drivers that read device->kvm Thanks, the code is right, and the test with this patch alone answers the patch 2 question. The first two fixes undo a mistake of mine: item 1 of my v2 reply said "in open_device(), not after it". That holds for vfio_ap and zdev, but KVMGT also calls kvm_write_track_add_gfn() on device->kvm while the guest runs. Details are in the reply to the patch. For the mainline version (VSTOR-153437): all three drivers already take their own reference on the kvm in open_device(). So upstream may prefer the core to hold its reference only across open_device() and drop it right after, with no flag at all. Worth raising there. -- Konstantin Khorenko, Virtuozzo Linux Kernel Team _______________________________________________ Devel mailing list Devel@openvz.org https://lists.openvz.org/mailman/listinfo/devel