Am 26.08.21 um 15:43 schrieb Andrey Grodzovsky:
Ping
Andrey
On 2021-08-25 11:36 a.m., Andrey Grodzovsky wrote:
On 2021-08-25 2:43 a.m., Christian König wrote:
Am 24.08.21 um 23:01 schrieb Andrey Grodzovsky:
Handle all DMA IOMMU group related dependencies before the
group is removed and we try to access it after free.
Signed-off-by: Andrey Grodzovsky <andrey.grodzovsky@xxxxxxx>
---
drivers/gpu/drm/amd/amdgpu/amdgpu_device.c | 2 +
drivers/gpu/drm/amd/amdgpu/amdgpu_ttm.c | 50
++++++++++++++++++++++
drivers/gpu/drm/amd/amdgpu/amdgpu_ttm.h | 1 +
3 files changed, 53 insertions(+)
diff --git a/drivers/gpu/drm/amd/amdgpu/amdgpu_device.c
b/drivers/gpu/drm/amd/amdgpu/amdgpu_device.c
index 0b5764aa98a4..288a465b8101 100644
--- a/drivers/gpu/drm/amd/amdgpu/amdgpu_device.c
+++ b/drivers/gpu/drm/amd/amdgpu/amdgpu_device.c
@@ -3860,6 +3860,8 @@ void amdgpu_device_fini_hw(struct
amdgpu_device *adev)
amdgpu_device_ip_fini_early(adev);
+ amdgpu_ttm_clear_dma_mappings(adev);
+
amdgpu_gart_dummy_page_fini(adev);
amdgpu_device_unmap_mmio(adev);
diff --git a/drivers/gpu/drm/amd/amdgpu/amdgpu_ttm.c
b/drivers/gpu/drm/amd/amdgpu/amdgpu_ttm.c
index 446943e32e3e..f73d807db3b0 100644
--- a/drivers/gpu/drm/amd/amdgpu/amdgpu_ttm.c
+++ b/drivers/gpu/drm/amd/amdgpu/amdgpu_ttm.c
@@ -64,6 +64,7 @@
static int amdgpu_ttm_backend_bind(struct ttm_device *bdev,
struct ttm_tt *ttm,
struct ttm_resource *bo_mem);
+
static void amdgpu_ttm_backend_unbind(struct ttm_device *bdev,
struct ttm_tt *ttm);
@@ -2293,6 +2294,55 @@ static ssize_t amdgpu_iomem_write(struct
file *f, const char __user *buf,
return result;
}
+void amdgpu_ttm_clear_dma_mappings(struct amdgpu_device *adev)
I strongly think that this function should be part of TTM. Something
like ttm_device_force_unpopulate.
Yes, this something I also wanted but see bellow
+{
+ struct ttm_device *bdev = &adev->mman.bdev;
+ struct ttm_resource_manager *man;
+ struct ttm_buffer_object *bo;
+ unsigned int i, j;
+
+ spin_lock(&bdev->lru_lock);
+ for (i = TTM_PL_SYSTEM; i < TTM_NUM_MEM_TYPES; ++i) {
+ man = ttm_manager_type(bdev, i);
+ if (!man || !man->use_tt)
+ continue;
+
+ while (!list_empty(&man->pinned)) {
+ bo = list_first_entry(&man->pinned, struct
ttm_buffer_object, lru);
+ /* Take ref against racing releases once lru_lock is
unlocked */
+ ttm_bo_get(bo);
+ list_del_init(&bo->lru);
+ spin_unlock(&bdev->lru_lock);
+
+ if (bo->ttm) {
+ amdgpu_ttm_backend_unbind(bo->bdev, bo->ttm);
amdgpu_ttm_backend_unbind is needed to be called separately from
ttm_tt_unpopulate to take care of code
flows that do dma mapping though the gart bind and not through
ttm_tt_populate, Since it's inside amdgpu
i had to place the entire function in amdgpu. Any suggestions ?
I think I've fixed exactly that just recently, see the patch here:
commit b7e8b086ffbc03b890ed22ae63ed5e5bd319d184
Author: Christian König <ckoenig.leichtzumerken@xxxxxxxxx>
Date: Wed Jul 28 15:05:49 2021 +0200
drm/amdgpu: unbind in amdgpu_ttm_tt_unpopulate
Doing this in amdgpu_ttm_backend_destroy() is to late.
It turned out that this is not a good idea at all because it leaves
pointers
to freed up system memory pages in the GART tables of the drivers.
But that probably hasn't showed up in amd-staging-drm-next yet.
Christian.
Andrey
+ ttm_tt_destroy_common(bo->bdev, bo->ttm);
Then you can also cleanly use ttm_tt_unpopulate here, cause this
will result in incorrect statistics inside TTM atm.
Regards,
Christian.
+ }
+
+ ttm_bo_put(bo);
+ spin_lock(&bdev->lru_lock);
+ }
+
+ for (j = 0; j < TTM_MAX_BO_PRIORITY; ++j) {
+ while (!list_empty(&man->lru[j])) {
+ bo = list_first_entry(&man->lru[j], struct
ttm_buffer_object, lru);
+ ttm_bo_get(bo);
+ list_del_init(&bo->lru);
+ spin_unlock(&bdev->lru_lock);
+
+ if (bo->ttm) {
+ amdgpu_ttm_backend_unbind(bo->bdev, bo->ttm);
+ ttm_tt_destroy_common(bo->bdev, bo->ttm);
+ }
+ ttm_bo_put(bo);
+ spin_lock(&bdev->lru_lock);
+ }
+ }
+ }
+ spin_unlock(&bdev->lru_lock);
+
+}
+
static const struct file_operations amdgpu_ttm_iomem_fops = {
.owner = THIS_MODULE,
.read = amdgpu_iomem_read,
diff --git a/drivers/gpu/drm/amd/amdgpu/amdgpu_ttm.h
b/drivers/gpu/drm/amd/amdgpu/amdgpu_ttm.h
index e69f3e8e06e5..02c8eac48a64 100644
--- a/drivers/gpu/drm/amd/amdgpu/amdgpu_ttm.h
+++ b/drivers/gpu/drm/amd/amdgpu/amdgpu_ttm.h
@@ -190,6 +190,7 @@ bool amdgpu_ttm_tt_is_readonly(struct ttm_tt
*ttm);
uint64_t amdgpu_ttm_tt_pde_flags(struct ttm_tt *ttm, struct
ttm_resource *mem);
uint64_t amdgpu_ttm_tt_pte_flags(struct amdgpu_device *adev,
struct ttm_tt *ttm,
struct ttm_resource *mem);
+void amdgpu_ttm_clear_dma_mappings(struct amdgpu_device *adev);
void amdgpu_ttm_debugfs_init(struct amdgpu_device *adev);
