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 75A28C433EF for ; Wed, 6 Jul 2022 15:39:40 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S233399AbiGFPji (ORCPT ); Wed, 6 Jul 2022 11:39:38 -0400 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:57146 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S234682AbiGFPhn (ORCPT ); Wed, 6 Jul 2022 11:37:43 -0400 Received: from ams.source.kernel.org (ams.source.kernel.org [IPv6:2604:1380:4601:e00::1]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id 3E45229806; Wed, 6 Jul 2022 08:34:14 -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 ams.source.kernel.org (Postfix) with ESMTPS id DA6D6B81D97; Wed, 6 Jul 2022 15:34:12 +0000 (UTC) Received: by smtp.kernel.org (Postfix) with ESMTPSA id B1A1AC385A5; Wed, 6 Jul 2022 15:34:10 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=k20201202; t=1657121651; bh=KtcIH+E3c9VLP7E/93kgfkyPI4Y4Eqggbw0U3c+oQjc=; h=From:To:Cc:Subject:Date:In-Reply-To:References:From; b=QUEPFA1ecu6tzN5W0ylPYRMXmwq2wrBy0sI/G8FWhrXDfM2mccmZfMfITFQjBtU8V piSUZt5jm+C9BPn6/ZUPqYuA5ySZ65Bw/8T4z+scrbB4aWRw4comTwfoHOJ+qZ6ERm Yp0e2gPPVjidvWI4X8dCarEyZQHSqUeLuy0FpQcCrDD2HA5kF2373MeX7cnQF/B1Si h3mA9R/56QNshkUSykdPSPe2WIffH99Bw87h9yh4m9Qv9wx5pWgOG6/Jk9fWRRIyAd qMNIId8b/w/NUsQ6gEFkr5TKIUcBXfOvTp8KKCq6QW+Rs7EDVaWaTzW1xlJsgcGGie naW8ZJ6siWPug== 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 4.9 2/5] virtio_mmio: Restore guest page size on resume Date: Wed, 6 Jul 2022 11:34:04 -0400 Message-Id: <20220706153407.1598915-2-sashal@kernel.org> X-Mailer: git-send-email 2.35.1 In-Reply-To: <20220706153407.1598915-1-sashal@kernel.org> References: <20220706153407.1598915-1-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 d69f0c5135ff..413f6af4d132 100644 --- a/drivers/virtio/virtio_mmio.c +++ b/drivers/virtio/virtio_mmio.c @@ -502,6 +502,9 @@ 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