LinuxLists.cc - [PATCH] drm/virtio: fix memory leak of vbuf

2024-04-02 10:16:26

Subject: [PATCH] drm/virtio: fix memory leak of vbuf

Both virtio_gpu_queue_ctrl_buffer and virtio_gpu_queue_cursor use
virtqueue_add_sgs to upload the structure virtio_gpu_vbuffer * vbuf
to virtqueue. However, when virtqueue_add_sgs returns -EIO or -ENOMEM,
it means vbuf upload failed, and vbuf will not be able to be
free by virtio_gpu_dequeue_*_func, resulting in a continuous increase
in memory allocated to vgdev ->vbufs.

Therefore, when upload fails，vbuf needs to be free directly.

Signed-off-by: Weishi Li <[email protected]>
---
drivers/gpu/drm/virtio/virtgpu_vq.c | 14 +++++++++-----
1 file changed, 9 insertions(+), 5 deletions(-)

diff --git a/drivers/gpu/drm/virtio/virtgpu_vq.c b/drivers/gpu/drm/virtio/virtgpu_vq.c
index b1a00c0c25a7..26f2e45635c1 100644
--- a/drivers/gpu/drm/virtio/virtgpu_vq.c
+++ b/drivers/gpu/drm/virtio/virtgpu_vq.c
@@ -356,12 +356,14 @@ static int virtio_gpu_queue_ctrl_sgs(struct virtio_gpu_device *vgdev,

ret = virtqueue_add_sgs(vq, sgs, outcnt, incnt, vbuf, GFP_ATOMIC);
WARN_ON(ret);
+ if (ret < 0 && ret != -ENOSPC) {
+ free_vbuf(vgdev, vbuf);
+ } else {
+ vbuf->seqno = ++vgdev->ctrlq.seqno;
+ trace_virtio_gpu_cmd_queue(vq, virtio_gpu_vbuf_ctrl_hdr(vbuf), vbuf->seqno);

- vbuf->seqno = ++vgdev->ctrlq.seqno;
- trace_virtio_gpu_cmd_queue(vq, virtio_gpu_vbuf_ctrl_hdr(vbuf), vbuf->seqno);
-
- atomic_inc(&vgdev->pending_commands);
-
+ atomic_inc(&vgdev->pending_commands);
+ }
spin_unlock(&vgdev->ctrlq.qlock);

drm_dev_exit(idx);
@@ -469,6 +471,8 @@ static void virtio_gpu_queue_cursor(struct virtio_gpu_device *vgdev,
wait_event(vgdev->cursorq.ack_queue, vq->num_free >= outcnt);
spin_lock(&vgdev->cursorq.qlock);
goto retry;
+ else if (ret < 0) {
+ free_vbuf(vgdev, vbuf);
} else {
vbuf->seqno = ++vgdev->cursorq.seqno;
trace_virtio_gpu_cmd_queue(vq,
--
2.25.1

2024-04-29 03:10:37

by Weishi Li

[permalink] [raw]

Subject: [PATCH] [PATCH RESEND] drm/virtio: fix memory leak of vbuf

2024-04-29 06:25:20

by Markus Elfring

[permalink] [raw]

Subject: Re: [PATCH] drm/virtio: fix memory leak of vbuf

…
> Therefore, when upload fails，vbuf needs to be free directly.

Please choose a corresponding imperative wording for an improved change description.
https://git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux.git/tree/Documentation/process/submitting-patches.rst?h=v6.9-rc5#n94

Regards,
Markus

2024-04-30 21:35:11

by kernel test robot

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Subject: Re: [PATCH] [PATCH RESEND] drm/virtio: fix memory leak of vbuf

2024-04-30 22:51:27

by kernel test robot

[permalink] [raw]

Subject: Re: [PATCH] [PATCH RESEND] drm/virtio: fix memory leak of vbuf

Hi Weishi,

kernel test robot noticed the following build errors:

[auto build test ERROR on drm-misc/drm-misc-next]
[also build test ERROR on drm/drm-next drm-exynos/exynos-drm-next drm-intel/for-linux-next drm-intel/for-linux-next-fixes drm-tip/drm-tip linus/master v6.9-rc6 next-20240430]
[If your patch is applied to the wrong git tree, kindly drop us a note.
And when submitting patch, we suggest to use '--base' as documented in
https://git-scm.com/docs/git-format-patch#_base_tree_information]

url: https://github.com/intel-lab-lkp/linux/commits/Weishi-Li/drm-virtio-fix-memory-leak-of-vbuf/20240430-132447
base: git://anongit.freedesktop.org/drm/drm-misc drm-misc-next
patch link: https://lore.kernel.org/r/20240429030541.56702-1-liweishi%40kylinos.cn
patch subject: [PATCH] [PATCH RESEND] drm/virtio: fix memory leak of vbuf
config: hexagon-randconfig-001-20240501 (https://download.01.org/0day-ci/archive/20240501/[email protected]/config)
compiler: clang version 15.0.7 (https://github.com/llvm/llvm-project.git 8dfdcc7b7bf66834a761bd8de445840ef68e4d1a)
reproduce (this is a W=1 build): (https://download.01.org/0day-ci/archive/20240501/[email protected]/reproduce)

If you fix the issue in a separate patch/commit (i.e. not just a new version of
the same patch/commit), kindly add following tags
| Reported-by: kernel test robot <[email protected]>
| Closes: https://lore.kernel.org/oe-kbuild-all/[email protected]/

All errors (new ones prefixed by >>):

In file included from drivers/gpu/drm/virtio/virtgpu_vq.c:29:
In file included from include/linux/dma-mapping.h:11:
In file included from include/linux/scatterlist.h:9:
In file included from arch/hexagon/include/asm/io.h:328:
include/asm-generic/io.h:547:31: warning: performing pointer arithmetic on a null pointer has undefined behavior [-Wnull-pointer-arithmetic]
val = __raw_readb(PCI_IOBASE + addr);
~~~~~~~~~~ ^
include/asm-generic/io.h:560:61: warning: performing pointer arithmetic on a null pointer has undefined behavior [-Wnull-pointer-arithmetic]
val = __le16_to_cpu((__le16 __force)__raw_readw(PCI_IOBASE + addr));
~~~~~~~~~~ ^
include/uapi/linux/byteorder/little_endian.h:37:51: note: expanded from macro '__le16_to_cpu'
#define __le16_to_cpu(x) ((__force __u16)(__le16)(x))
^
In file included from drivers/gpu/drm/virtio/virtgpu_vq.c:29:
In file included from include/linux/dma-mapping.h:11:
In file included from include/linux/scatterlist.h:9:
In file included from arch/hexagon/include/asm/io.h:328:
include/asm-generic/io.h:573:61: warning: performing pointer arithmetic on a null pointer has undefined behavior [-Wnull-pointer-arithmetic]
val = __le32_to_cpu((__le32 __force)__raw_readl(PCI_IOBASE + addr));
~~~~~~~~~~ ^
include/uapi/linux/byteorder/little_endian.h:35:51: note: expanded from macro '__le32_to_cpu'
#define __le32_to_cpu(x) ((__force __u32)(__le32)(x))
^
In file included from drivers/gpu/drm/virtio/virtgpu_vq.c:29:
In file included from include/linux/dma-mapping.h:11:
In file included from include/linux/scatterlist.h:9:
In file included from arch/hexagon/include/asm/io.h:328:
include/asm-generic/io.h:584:33: warning: performing pointer arithmetic on a null pointer has undefined behavior [-Wnull-pointer-arithmetic]
__raw_writeb(value, PCI_IOBASE + addr);
~~~~~~~~~~ ^
include/asm-generic/io.h:594:59: warning: performing pointer arithmetic on a null pointer has undefined behavior [-Wnull-pointer-arithmetic]
__raw_writew((u16 __force)cpu_to_le16(value), PCI_IOBASE + addr);
~~~~~~~~~~ ^
include/asm-generic/io.h:604:59: warning: performing pointer arithmetic on a null pointer has undefined behavior [-Wnull-pointer-arithmetic]
__raw_writel((u32 __force)cpu_to_le32(value), PCI_IOBASE + addr);
~~~~~~~~~~ ^
drivers/gpu/drm/virtio/virtgpu_vq.c:474:2: error: expected expression
else if (ret < 0) {
^
>> drivers/gpu/drm/virtio/virtgpu_vq.c:503:1: error: function definition is not allowed here
{
^
drivers/gpu/drm/virtio/virtgpu_vq.c:523:1: error: function definition is not allowed here
{
^
drivers/gpu/drm/virtio/virtgpu_vq.c:534:1: error: function definition is not allowed here
{
^
drivers/gpu/drm/virtio/virtgpu_vq.c:556:1: error: function definition is not allowed here
{
^
drivers/gpu/drm/virtio/virtgpu_vq.c:580:1: error: function definition is not allowed here
{
^
drivers/gpu/drm/virtio/virtgpu_vq.c:604:1: error: function definition is not allowed here
{
^
drivers/gpu/drm/virtio/virtgpu_vq.c:635:1: error: function definition is not allowed here
{
^
drivers/gpu/drm/virtio/virtgpu_vq.c:654:1: error: function definition is not allowed here
{
^
drivers/gpu/drm/virtio/virtgpu_vq.c:683:1: error: function definition is not allowed here
{
^
drivers/gpu/drm/virtio/virtgpu_vq.c:704:1: error: function definition is not allowed here
{
^
drivers/gpu/drm/virtio/virtgpu_vq.c:729:1: error: function definition is not allowed here
{
^
drivers/gpu/drm/virtio/virtgpu_vq.c:741:1: error: function definition is not allowed here
{
^
drivers/gpu/drm/virtio/virtgpu_vq.c:767:1: error: function definition is not allowed here
{
^
drivers/gpu/drm/virtio/virtgpu_vq.c:790:1: error: function definition is not allowed here
{
^
drivers/gpu/drm/virtio/virtgpu_vq.c:815:1: error: function definition is not allowed here
{
^
drivers/gpu/drm/virtio/virtgpu_vq.c:889:1: error: function definition is not allowed here
{
^
drivers/gpu/drm/virtio/virtgpu_vq.c:919:1: error: function definition is not allowed here
{
^
drivers/gpu/drm/virtio/virtgpu_vq.c:936:1: error: function definition is not allowed here
{
^
fatal error: too many errors emitted, stopping now [-ferror-limit=]
6 warnings and 20 errors generated.

vim +503 drivers/gpu/drm/virtio/virtgpu_vq.c

dc5698e80cf724 Dave Airlie 2013-09-09 492
dc5698e80cf724 Dave Airlie 2013-09-09 493 /* just create gem objects for userspace and long lived objects,
5d883850dc23a5 Rodrigo Siqueira 2018-02-22 494 * just use dma_alloced pages for the queue objects?
5d883850dc23a5 Rodrigo Siqueira 2018-02-22 495 */
dc5698e80cf724 Dave Airlie 2013-09-09 496
dc5698e80cf724 Dave Airlie 2013-09-09 497 /* create a basic resource */
dc5698e80cf724 Dave Airlie 2013-09-09 498 void virtio_gpu_cmd_create_resource(struct virtio_gpu_device *vgdev,
23c897d72ca806 Gerd Hoffmann 2018-10-19 499 struct virtio_gpu_object *bo,
530b28426a94b8 Gerd Hoffmann 2019-03-18 500 struct virtio_gpu_object_params *params,
e2324300f427ff Gerd Hoffmann 2019-08-29 501 struct virtio_gpu_object_array *objs,
530b28426a94b8 Gerd Hoffmann 2019-03-18 502 struct virtio_gpu_fence *fence)
dc5698e80cf724 Dave Airlie 2013-09-09 @503 {
dc5698e80cf724 Dave Airlie 2013-09-09 504 struct virtio_gpu_resource_create_2d *cmd_p;
dc5698e80cf724 Dave Airlie 2013-09-09 505 struct virtio_gpu_vbuffer *vbuf;
dc5698e80cf724 Dave Airlie 2013-09-09 506
dc5698e80cf724 Dave Airlie 2013-09-09 507 cmd_p = virtio_gpu_alloc_cmd(vgdev, &vbuf, sizeof(*cmd_p));
dc5698e80cf724 Dave Airlie 2013-09-09 508 memset(cmd_p, 0, sizeof(*cmd_p));
e2324300f427ff Gerd Hoffmann 2019-08-29 509 vbuf->objs = objs;
dc5698e80cf724 Dave Airlie 2013-09-09 510
dc5698e80cf724 Dave Airlie 2013-09-09 511 cmd_p->hdr.type = cpu_to_le32(VIRTIO_GPU_CMD_RESOURCE_CREATE_2D);
724cfdfd667a28 Gerd Hoffmann 2018-10-19 512 cmd_p->resource_id = cpu_to_le32(bo->hw_res_handle);
f9659329f222a6 Gerd Hoffmann 2019-03-18 513 cmd_p->format = cpu_to_le32(params->format);
f9659329f222a6 Gerd Hoffmann 2019-03-18 514 cmd_p->width = cpu_to_le32(params->width);
f9659329f222a6 Gerd Hoffmann 2019-03-18 515 cmd_p->height = cpu_to_le32(params->height);
dc5698e80cf724 Dave Airlie 2013-09-09 516
e19d341174b679 Chia-I Wu 2020-02-05 517 virtio_gpu_queue_fenced_ctrl_buffer(vgdev, vbuf, fence);
23c897d72ca806 Gerd Hoffmann 2018-10-19 518 bo->created = true;
dc5698e80cf724 Dave Airlie 2013-09-09 519 }
dc5698e80cf724 Dave Airlie 2013-09-09 520

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