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 DB4D1C433EF for ; Wed, 6 Jul 2022 15:37:06 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S234390AbiGFPhE (ORCPT ); Wed, 6 Jul 2022 11:37:04 -0400 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:46148 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S234192AbiGFPgH (ORCPT ); Wed, 6 Jul 2022 11:36:07 -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 EC7732A955; Wed, 6 Jul 2022 08:33:40 -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 004FD61FF9; Wed, 6 Jul 2022 15:33:40 +0000 (UTC) Received: by smtp.kernel.org (Postfix) with ESMTPSA id B772BC385A5; Wed, 6 Jul 2022 15:33:38 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=k20201202; t=1657121619; bh=mRSL+apNKrvio6NVOXKtCrU99U9hQ2heTqOSh0hWygI=; h=From:To:Cc:Subject:Date:In-Reply-To:References:From; b=s3cP/4gn6x9lcANWUUUOl89CWP4wdkqOU2WuYCW7wJR+d4k5PYvf7X/nVrueMkM/5 MZDneJXiaaBMIM+7cm+WhYX5i30k67jcMaFVWZq2Oip5/4UDf1RxuJerDUldZcmHH+ FIyxxII9nVRe0LL7Qecc3lcsx8w0WDsEJ6SzX8faknhnO/Hr79yWBkDQyItZLtLtbA 9zno4RVVFCSEeMO+IwSPcmMi8PGYOwbiSWehy/+JC4NOAGQlThTk8ObocynXtt8Ned wlikhSCbOCinNFCqiPnRS22Pdszo4EV7Vf/0b0qKnoT3gkNKc7RmYcI0ypZamPmbOW NZr1Y0J185WgA== From: Sasha Levin To: linux-kernel@vger.kernel.org, stable@vger.kernel.org Cc: Stephan Gerhold , "Michael S . Tsirkin" , Sasha Levin , jasowang@redhat.com, virtualization@lists.linux-foundation.org Subject: [PATCH AUTOSEL 4.19 2/8] virtio_mmio: Restore guest page size on resume Date: Wed, 6 Jul 2022 11:33:29 -0400 Message-Id: <20220706153335.1598699-2-sashal@kernel.org> X-Mailer: git-send-email 2.35.1 In-Reply-To: <20220706153335.1598699-1-sashal@kernel.org> References: <20220706153335.1598699-1-sashal@kernel.org> MIME-Version: 1.0 X-stable: review X-Patchwork-Hint: Ignore 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 79474bd0c52c..17cd682acc22 100644 --- a/drivers/virtio/virtio_mmio.c +++ b/drivers/virtio/virtio_mmio.c @@ -521,6 +521,9 @@ 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