From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: X-Spam-Checker-Version: SpamAssassin 3.4.0 (2014-02-07) on aws-us-west-2-korg-lkml-1.web.codeaurora.org Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by smtp.lore.kernel.org (Postfix) with ESMTP id BB911C433EF for ; Tue, 19 Jul 2022 12:12:16 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S236172AbiGSMMO (ORCPT ); Tue, 19 Jul 2022 08:12:14 -0400 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:51594 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S238336AbiGSMKP (ORCPT ); Tue, 19 Jul 2022 08:10:15 -0400 Received: from dfw.source.kernel.org (dfw.source.kernel.org [IPv6:2604:1380:4641:c500::1]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id 0ABA1422C5; Tue, 19 Jul 2022 05:03:20 -0700 (PDT) Received: from smtp.kernel.org (relay.kernel.org [52.25.139.140]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by dfw.source.kernel.org (Postfix) with ESMTPS id 8559461632; Tue, 19 Jul 2022 12:03:19 +0000 (UTC) Received: by smtp.kernel.org (Postfix) with ESMTPSA id 6A4F8C341C6; Tue, 19 Jul 2022 12:03:18 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=linuxfoundation.org; s=korg; t=1658232198; bh=3Ebo41DSRWuzz7t4znUhen4wmpTzViKj875cur3+ojk=; h=From:To:Cc:Subject:Date:In-Reply-To:References:From; b=MHgmke3TpXuTQtzF5lZZJXNgce2ygm2GAk3gr4TK1U3WgXpQ6c7KSJzPnEvfC4hkR Fcb0xTKpN7UA8Po27XFvySKBq2e95UHdodXf+0BFSgYzjyRwaa6D7aRgn1Hx+UT/yB OvQAmA7Ju/G/tlIYSiQsuuKQgE6RqCxYVL0mERAU= From: Greg Kroah-Hartman To: linux-kernel@vger.kernel.org Cc: Greg Kroah-Hartman , stable@vger.kernel.org, Stephan Gerhold , "Michael S. Tsirkin" , Sasha Levin Subject: [PATCH 5.4 46/71] virtio_mmio: Restore guest page size on resume Date: Tue, 19 Jul 2022 13:54:09 +0200 Message-Id: <20220719114556.781198549@linuxfoundation.org> X-Mailer: git-send-email 2.37.1 In-Reply-To: <20220719114552.477018590@linuxfoundation.org> References: <20220719114552.477018590@linuxfoundation.org> User-Agent: quilt/0.66 MIME-Version: 1.0 Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 8bit Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org From: Stephan Gerhold [ Upstream commit e0c2ce8217955537dd5434baeba061f209797119 ] Virtio devices might lose their state when the VMM is restarted after a suspend to disk (hibernation) cycle. This means that the guest page size register must be restored for the virtio_mmio legacy interface, since otherwise the virtio queues are not functional. This is particularly problematic for QEMU that currently still defaults to using the legacy interface for virtio_mmio. Write the guest page size register again in virtio_mmio_restore() to make legacy virtio_mmio devices work correctly after hibernation. Signed-off-by: Stephan Gerhold Message-Id: <20220621110621.3638025-3-stephan.gerhold@kernkonzept.com> Signed-off-by: Michael S. Tsirkin Signed-off-by: Sasha Levin --- drivers/virtio/virtio_mmio.c | 3 +++ 1 file changed, 3 insertions(+) diff --git a/drivers/virtio/virtio_mmio.c b/drivers/virtio/virtio_mmio.c index 2a2d817caeff..e781e5e9215f 100644 --- a/drivers/virtio/virtio_mmio.c +++ b/drivers/virtio/virtio_mmio.c @@ -527,6 +527,9 @@ static int virtio_mmio_restore(struct device *dev) { struct virtio_mmio_device *vm_dev = dev_get_drvdata(dev); + if (vm_dev->version == 1) + writel(PAGE_SIZE, vm_dev->base + VIRTIO_MMIO_GUEST_PAGE_SIZE); + return virtio_device_restore(&vm_dev->vdev); } -- 2.35.1