On 2/3/24 00:06, Timur Tabi wrote:
Nouveau manages GSP-RM DMA buffers with nvkm_gsp_mem objects. Several of
these buffers are never dealloced. Some of them can be deallocated
right after GSP-RM is initialized, but the rest need to stay until the
driver unloads.
Also futher bullet-proof these objects by poisoning the buffer and
clearing the nvkm_gsp_mem object when it is deallocated. Poisoning
the buffer should trigger an error (or crash) from GSP-RM if it tries
to access the buffer after we've deallocated it, because we were wrong
about when it is safe to deallocate.
Finally, change the mem->size field to a size_t because that's the same
type that dma_alloc_coherent expects.
Fixes: 176fdcbddfd2 ("drm/nouveau/gsp/r535: add support for booting GSP-RM")
Signed-off-by: Timur Tabi <ttabi@xxxxxxxxxx>
Series applied to drm-misc-fixes, thanks!
---
v3: use size_t
v2: add buffer poisoning
.../gpu/drm/nouveau/include/nvkm/subdev/gsp.h | 2 +-
.../gpu/drm/nouveau/nvkm/subdev/gsp/r535.c | 59 ++++++++++++-------
2 files changed, 39 insertions(+), 22 deletions(-)
diff --git a/drivers/gpu/drm/nouveau/include/nvkm/subdev/gsp.h b/drivers/gpu/drm/nouveau/include/nvkm/subdev/gsp.h
index 5c6b8536e31c..3fbc57b16a05 100644
--- a/drivers/gpu/drm/nouveau/include/nvkm/subdev/gsp.h
+++ b/drivers/gpu/drm/nouveau/include/nvkm/subdev/gsp.h
@@ -9,7 +9,7 @@
#define GSP_PAGE_SIZE BIT(GSP_PAGE_SHIFT)
struct nvkm_gsp_mem {
- u32 size;
+ size_t size;
void *data;
dma_addr_t addr;
};
diff --git a/drivers/gpu/drm/nouveau/nvkm/subdev/gsp/r535.c b/drivers/gpu/drm/nouveau/nvkm/subdev/gsp/r535.c
index 17fc429ee50b..a9030eb83b4d 100644
--- a/drivers/gpu/drm/nouveau/nvkm/subdev/gsp/r535.c
+++ b/drivers/gpu/drm/nouveau/nvkm/subdev/gsp/r535.c
@@ -999,6 +999,32 @@ r535_gsp_rpc_get_gsp_static_info(struct nvkm_gsp *gsp)
return 0;
}
+static void
+nvkm_gsp_mem_dtor(struct nvkm_gsp *gsp, struct nvkm_gsp_mem *mem)
+{
+ if (mem->data) {
+ /*
+ * Poison the buffer to catch any unexpected access from
+ * GSP-RM if the buffer was prematurely freed.
+ */
+ memset(mem->data, 0xFF, mem->size);
+
+ dma_free_coherent(gsp->subdev.device->dev, mem->size, mem->data, mem->addr);
+ memset(mem, 0, sizeof(*mem));
+ }
+}
+
+static int
+nvkm_gsp_mem_ctor(struct nvkm_gsp *gsp, size_t size, struct nvkm_gsp_mem *mem)
+{
+ mem->size = size;
+ mem->data = dma_alloc_coherent(gsp->subdev.device->dev, size, &mem->addr, GFP_KERNEL);
+ if (WARN_ON(!mem->data))
+ return -ENOMEM;
+
+ return 0;
+}
+
static int
r535_gsp_postinit(struct nvkm_gsp *gsp)
{
@@ -1026,6 +1052,13 @@ r535_gsp_postinit(struct nvkm_gsp *gsp)
nvkm_inth_allow(&gsp->subdev.inth);
nvkm_wr32(device, 0x110004, 0x00000040);
+
+ /* Release the DMA buffers that were needed only for boot and init */
+ nvkm_gsp_mem_dtor(gsp, &gsp->boot.fw);
+ nvkm_gsp_mem_dtor(gsp, &gsp->libos);
+ nvkm_gsp_mem_dtor(gsp, &gsp->rmargs);
+ nvkm_gsp_mem_dtor(gsp, &gsp->wpr_meta);
+
return ret;
}
@@ -1760,27 +1793,6 @@ r535_gsp_msg_run_cpu_sequencer(void *priv, u32 fn, void *repv, u32 repc)
return 0;
}
-static void
-nvkm_gsp_mem_dtor(struct nvkm_gsp *gsp, struct nvkm_gsp_mem *mem)
-{
- if (mem->data) {
- dma_free_coherent(gsp->subdev.device->dev, mem->size, mem->data, mem->addr);
- mem->data = NULL;
- }
-}
-
-static int
-nvkm_gsp_mem_ctor(struct nvkm_gsp *gsp, u32 size, struct nvkm_gsp_mem *mem)
-{
- mem->size = size;
- mem->data = dma_alloc_coherent(gsp->subdev.device->dev, size, &mem->addr, GFP_KERNEL);
- if (WARN_ON(!mem->data))
- return -ENOMEM;
-
- return 0;
-}
-
-
static int
r535_gsp_booter_unload(struct nvkm_gsp *gsp, u32 mbox0, u32 mbox1)
{
@@ -2378,6 +2390,11 @@ r535_gsp_dtor(struct nvkm_gsp *gsp)
mutex_destroy(&gsp->cmdq.mutex);
r535_gsp_dtor_fws(gsp);
+
+ nvkm_gsp_mem_dtor(gsp, &gsp->shm.mem);
+ nvkm_gsp_mem_dtor(gsp, &gsp->loginit);
+ nvkm_gsp_mem_dtor(gsp, &gsp->logintr);
+ nvkm_gsp_mem_dtor(gsp, &gsp->logrm);
}
int
