Am 23.04.24 um 15:04 schrieb Philip Yang:
To test RDMA using dummy driver on the system without NIC/RDMA
device, the get/put dma pages pass in null device pointer, skip the
dma map/unmap resource and sg table to avoid null pointer access.
Well just to make it clear this patch is really a no-go for upstreaming.
The RDMA code isn't upstream as far as I know and doing this here is
really not a good idea even internally.
Regards,
Christian.
Signed-off-by: Philip Yang <Philip.Yang@xxxxxxx>
---
drivers/gpu/drm/amd/amdgpu/amdgpu_vram_mgr.c | 33 +++++++++++---------
1 file changed, 19 insertions(+), 14 deletions(-)
diff --git a/drivers/gpu/drm/amd/amdgpu/amdgpu_vram_mgr.c b/drivers/gpu/drm/amd/amdgpu/amdgpu_vram_mgr.c
index 6c7133bf51d8..101a85263b53 100644
--- a/drivers/gpu/drm/amd/amdgpu/amdgpu_vram_mgr.c
+++ b/drivers/gpu/drm/amd/amdgpu/amdgpu_vram_mgr.c
@@ -698,12 +698,15 @@ int amdgpu_vram_mgr_alloc_sgt(struct amdgpu_device *adev,
unsigned long size = min(cursor.size, MAX_SG_SEGMENT_SIZE);
dma_addr_t addr;
- addr = dma_map_resource(dev, phys, size, dir,
- DMA_ATTR_SKIP_CPU_SYNC);
- r = dma_mapping_error(dev, addr);
- if (r)
- goto error_unmap;
-
+ if (dev) {
+ addr = dma_map_resource(dev, phys, size, dir,
+ DMA_ATTR_SKIP_CPU_SYNC);
+ r = dma_mapping_error(dev, addr);
+ if (r)
+ goto error_unmap;
+ } else {
+ addr = phys;
+ }
sg_set_page(sg, NULL, size, 0);
sg_dma_address(sg) = addr;
sg_dma_len(sg) = size;
@@ -717,10 +720,10 @@ int amdgpu_vram_mgr_alloc_sgt(struct amdgpu_device *adev,
for_each_sgtable_sg((*sgt), sg, i) {
if (!sg->length)
continue;
-
- dma_unmap_resource(dev, sg->dma_address,
- sg->length, dir,
- DMA_ATTR_SKIP_CPU_SYNC);
+ if (dev)
+ dma_unmap_resource(dev, sg->dma_address,
+ sg->length, dir,
+ DMA_ATTR_SKIP_CPU_SYNC);
}
sg_free_table(*sgt);
@@ -745,10 +748,12 @@ void amdgpu_vram_mgr_free_sgt(struct device *dev,
struct scatterlist *sg;
int i;
- for_each_sgtable_sg(sgt, sg, i)
- dma_unmap_resource(dev, sg->dma_address,
- sg->length, dir,
- DMA_ATTR_SKIP_CPU_SYNC);
+ if (dev) {
+ for_each_sgtable_sg(sgt, sg, i)
+ dma_unmap_resource(dev, sg->dma_address,
+ sg->length, dir,
+ DMA_ATTR_SKIP_CPU_SYNC);
+ }
sg_free_table(sgt);
kfree(sgt);
}
