1 Star 0 Fork 121

XuFei/src_openeuler_qemu

forked from src-openEuler/qemu 
加入 Gitee
与超过 1200万 开发者一起发现、参与优秀开源项目,私有仓库也完全免费 :)
免费加入
文件
该仓库未声明开源许可证文件(LICENSE),使用请关注具体项目描述及其代码上游依赖。
克隆/下载
virtio-bugfix-check-the-value-of-caches-before-acces.patch 1.39 KB
一键复制 编辑 原始数据 按行查看 历史
From 74ab61b4317f12b231fb2cbcd54a333a07efd678 Mon Sep 17 00:00:00 2001
From: Jinhua Cao <caojinhua1@huawei.com>
Date: Thu, 10 Feb 2022 14:37:52 +0800
Subject: [PATCH] virtio: bugfix: check the value of caches before accessing it
Vring caches may be NULL in check_vring_avail_num() if
virtio_reset() is called at the same time, such as when
the virtual machine starts.
So check it before accessing it in vring_avail_idx().
Signed-off-by: Jinhua Cao <caojinhua1@huawei.com>
---
hw/virtio/virtio.c | 11 +++++++++++
1 file changed, 11 insertions(+)
diff --git a/hw/virtio/virtio.c b/hw/virtio/virtio.c
index 9a2a83d507..b08fff9419 100644
--- a/hw/virtio/virtio.c
+++ b/hw/virtio/virtio.c
@@ -2863,8 +2863,19 @@ static const VMStateDescription vmstate_virtio = {
static void check_vring_avail_num(VirtIODevice *vdev, int index)
{
uint16_t nheads;
+ VRingMemoryRegionCaches *caches;
rcu_read_lock();
+ caches = qatomic_rcu_read(&vdev->vq[index].vring.caches);
+ if (caches == NULL) {
+ /*
+ * caches may be NULL if virtio_reset is called at the same time,
+ * such as when the virtual machine starts.
+ */
+ rcu_read_unlock();
+ return;
+ }
+
/* Check it isn't doing strange things with descriptor numbers. */
nheads = vring_avail_idx(&vdev->vq[index]) - vdev->vq[index].last_avail_idx;
if (nheads > vdev->vq[index].vring.num) {
--
2.27.0
马建仓 AI 助手
尝试更多
代码解读
代码找茬
代码优化
1
https://gitee.com/flyking001/src_openeuler_qemu.git
git@gitee.com:flyking001/src_openeuler_qemu.git
flyking001
src_openeuler_qemu
src_openeuler_qemu
master

搜索帮助