From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: X-Google-Smtp-Source: AB8JxZrkSfUAsUq7MEw+fazSuqgmex4DqdpCp3Unnr3v1yf0ciNdLFlCMBTwWLLf47U+LFB4I3Ui ARC-Seal: i=1; a=rsa-sha256; t=1525116444; cv=none; d=google.com; s=arc-20160816; b=Z7Q29kmn0B5L8YwDLcxX0JYpVl025ig28HFabBY8e8rW9TniGwpJB0OdP+5VXg9DVV pdMRmfK3RSd+O+xXqRRpipDfAE3fao3CybDtb8l1pn1lXgaZUhArz/m7uVetYPSGst43 GzWfJPKAA4yDgG+0HEk6+MqHJg33tV7AEmIZq0k4yO4z6lbxh3TvyCtL4kt3KDhNj+4P TvpxESca+kOnFWyq1gupvqBimsRjePMoSjTQ8/yaBDOx2ZYPgrLGqLuncY9qdKdHResk vw8nbh33cI8KI+lXTLW4tQ/HcTH+4l0B1cnyiZOa8ca7JPIbSAXoyz56pMIzxrniw+BZ PH+g== ARC-Message-Signature: i=1; a=rsa-sha256; c=relaxed/relaxed; d=google.com; s=arc-20160816; h=mime-version:user-agent:references:in-reply-to:message-id:date :subject:cc:to:from:dmarc-filter:arc-authentication-results; bh=Fm+DabXkO1nPCnIcyxnDGnbgpMga76E7bpXJlS1AIKs=; b=EXboU6gF6bfCkdtm7i2sBQ+VUREshEb/u4+7iLvKpa8OYV25cNwcG4HavsERqWtLKS oMp0+zC2HyFfTcUfZ3LAplx2fOAUeLZ6LyumMwRITw6LbqvBcxvqzHHjG8aedokZ9WeZ NTrrw235HH79rBplB8yxJAsovzskL+GU7C7QfYyNL3NqdaUdtdjLykcyOtUfUXb/pNsH IHsdo1oIlKNPzHzjgxgzaYamL5qHaciZtvmDR/OAtd1TYsYbXyoKoYDXcfWHgTUyaI6w UVZAqJEUSAoVsAm5nXTVI0yIuUbkYK8TTWTuyveYCcnp4e6Xall54294daYoa5CCXBCY fVcg== ARC-Authentication-Results: i=1; mx.google.com; spf=pass (google.com: best guess record for domain of srs0=k66p=ht=linuxfoundation.org=gregkh@kernel.org designates 198.145.29.99 as permitted sender) smtp.mailfrom=SRS0=K66P=HT=linuxfoundation.org=gregkh@kernel.org Authentication-Results: mx.google.com; spf=pass (google.com: best guess record for domain of srs0=k66p=ht=linuxfoundation.org=gregkh@kernel.org designates 198.145.29.99 as permitted sender) smtp.mailfrom=SRS0=K66P=HT=linuxfoundation.org=gregkh@kernel.org DMARC-Filter: OpenDMARC Filter v1.3.2 mail.kernel.org 0579422DAC Authentication-Results: mail.kernel.org; dmarc=none (p=none dis=none) header.from=linuxfoundation.org Authentication-Results: mail.kernel.org; spf=fail smtp.mailfrom=gregkh@linuxfoundation.org From: Greg Kroah-Hartman To: linux-kernel@vger.kernel.org Cc: Greg Kroah-Hartman , stable@vger.kernel.org, Alain Magloire , Gerd Hoffmann , Dave Airlie , Sean Paul Subject: [PATCH 4.14 28/91] drm/virtio: fix vq wait_event condition Date: Mon, 30 Apr 2018 12:24:10 -0700 Message-Id: <20180430184005.658968269@linuxfoundation.org> X-Mailer: git-send-email 2.17.0 In-Reply-To: <20180430184004.216234025@linuxfoundation.org> References: <20180430184004.216234025@linuxfoundation.org> User-Agent: quilt/0.65 X-stable: review MIME-Version: 1.0 Content-Type: text/plain; charset=UTF-8 X-getmail-retrieved-from-mailbox: INBOX X-GMAIL-LABELS: =?utf-8?b?IlxcU2VudCI=?= X-GMAIL-THRID: =?utf-8?q?1599200400304649329?= X-GMAIL-MSGID: =?utf-8?q?1599200500756226485?= X-Mailing-List: linux-kernel@vger.kernel.org List-ID: 4.14-stable review patch. If anyone has any objections, please let me know. ------------------ From: Gerd Hoffmann commit d02d270014f70dcab0117776b81a37b6fca745ae upstream. Wait until we have enough space in the virt queue to actually queue up our request. Avoids the guest spinning in case we have a non-zero amount of free entries but not enough for the request. Cc: stable@vger.kernel.org Reported-by: Alain Magloire Signed-off-by: Gerd Hoffmann Reviewed-by: Dave Airlie Link: http://patchwork.freedesktop.org/patch/msgid/20180403095904.11152-1-kraxel@redhat.com Signed-off-by: Sean Paul Signed-off-by: Greg Kroah-Hartman --- drivers/gpu/drm/virtio/virtgpu_vq.c | 4 ++-- 1 file changed, 2 insertions(+), 2 deletions(-) --- a/drivers/gpu/drm/virtio/virtgpu_vq.c +++ b/drivers/gpu/drm/virtio/virtgpu_vq.c @@ -291,7 +291,7 @@ retry: ret = virtqueue_add_sgs(vq, sgs, outcnt, incnt, vbuf, GFP_ATOMIC); if (ret == -ENOSPC) { spin_unlock(&vgdev->ctrlq.qlock); - wait_event(vgdev->ctrlq.ack_queue, vq->num_free); + wait_event(vgdev->ctrlq.ack_queue, vq->num_free >= outcnt + incnt); spin_lock(&vgdev->ctrlq.qlock); goto retry; } else { @@ -366,7 +366,7 @@ retry: ret = virtqueue_add_sgs(vq, sgs, outcnt, 0, vbuf, GFP_ATOMIC); if (ret == -ENOSPC) { spin_unlock(&vgdev->cursorq.qlock); - wait_event(vgdev->cursorq.ack_queue, vq->num_free); + wait_event(vgdev->cursorq.ack_queue, vq->num_free >= outcnt); spin_lock(&vgdev->cursorq.qlock); goto retry; } else {