Re: [PATCH] amdgpu: fixes memleak issue when init failed

From: Christian KÃnig
Date: Tue Apr 21 2020 - 09:03:36 EST


Am 21.04.20 um 14:09 schrieb èåå:
From: "Christian KÃnig" <christian.koenig@xxxxxxx>
Date: 2020-04-21 19:22:49
To: Bernard Zhao <bernard@xxxxxxxx>,Alex Deucher <alexander.deucher@xxxxxxx>,"David (ChunMing) Zhou" <David1.Zhou@xxxxxxx>,David Airlie <airlied@xxxxxxxx>,Daniel Vetter <daniel@xxxxxxxx>,Tom St Denis <tom.stdenis@xxxxxxx>,Ori Messinger <Ori.Messinger@xxxxxxx>,Sam Ravnborg <sam@xxxxxxxxxxxx>,amd-gfx@xxxxxxxxxxxxxxxxxxxxx,dri-devel@xxxxxxxxxxxxxxxxxxxxx,linux-kernel@xxxxxxxxxxxxxxx
Cc: opensource.kernel@xxxxxxxx
Subject: Re: [PATCH] amdgpu: fixes memleak issue when init failed>Am 21.04.20 um 13:17 schrieb Bernard Zhao:
VRAM manager and DRM MM when init failed, there is no operaction
to free kzalloc memory & remove device file.
This will lead to memleak & cause stability issue.
NAK, failure to create sysfs nodes are not critical.

Christian.

OK, get it.
By the way, should i modify this patch to just handle <kfree(mgr)> in error branch, or that it is also unnecessary?

What you can do is to drop the "return ret" if anything with the sysfs nodes goes wrong and instead print the error code.

It's really annoying that loading, unloading and loading the driver again sometimes fails because we have a bug in the sysfs files cleanup.

We certainly should fix those bugs as well, but they are just not critical for correct driver functionality.

Regards,
Christian.


Regards,
Bernard

Signed-off-by: Bernard Zhao <bernard@xxxxxxxx>
---
drivers/gpu/drm/amd/amdgpu/amdgpu_vram_mgr.c | 24 ++++++++++++++++----
1 file changed, 19 insertions(+), 5 deletions(-)

diff --git a/drivers/gpu/drm/amd/amdgpu/amdgpu_vram_mgr.c b/drivers/gpu/drm/amd/amdgpu/amdgpu_vram_mgr.c
index 82a3299e53c0..4c5fb153e6b4 100644
--- a/drivers/gpu/drm/amd/amdgpu/amdgpu_vram_mgr.c
+++ b/drivers/gpu/drm/amd/amdgpu/amdgpu_vram_mgr.c
@@ -175,30 +175,44 @@ static int amdgpu_vram_mgr_init(struct ttm_mem_type_manager *man,
ret = device_create_file(adev->dev, &dev_attr_mem_info_vram_total);
if (ret) {
DRM_ERROR("Failed to create device file mem_info_vram_total\n");
- return ret;
+ goto VRAM_TOTAL_FAIL;
}
ret = device_create_file(adev->dev, &dev_attr_mem_info_vis_vram_total);
if (ret) {
DRM_ERROR("Failed to create device file mem_info_vis_vram_total\n");
- return ret;
+ goto VIS_VRAM_TOTA_FAIL;
}
ret = device_create_file(adev->dev, &dev_attr_mem_info_vram_used);
if (ret) {
DRM_ERROR("Failed to create device file mem_info_vram_used\n");
- return ret;
+ goto VRAM_USED_FAIL;
}
ret = device_create_file(adev->dev, &dev_attr_mem_info_vis_vram_used);
if (ret) {
DRM_ERROR("Failed to create device file mem_info_vis_vram_used\n");
- return ret;
+ goto VIS_VRAM_USED_FAIL;
}
ret = device_create_file(adev->dev, &dev_attr_mem_info_vram_vendor);
if (ret) {
DRM_ERROR("Failed to create device file mem_info_vram_vendor\n");
- return ret;
+ goto VRAM_VERDOR_FAIL;
}
return 0;
+
+VRAM_VERDOR_FAIL:
+ device_remove_file(adev->dev, &dev_attr_mem_info_vis_vram_used);
+VIS_VRAM_USED_FAIL:
+ device_remove_file(adev->dev, &dev_attr_mem_info_vram_used);
+RVAM_USED_FAIL:
+ device_remove_file(adev->dev, &dev_attr_mem_info_vis_vram_total);
+VIS_VRAM_TOTA_FAIL:
+ device_remove_file(adev->dev, &dev_attr_mem_info_vram_total);
+VRAM_TOTAL_FAIL:
+ kfree(mgr);
+ man->priv = NULL;
+
+ return ret;
}
/**