Re: [PATCH v2] drm/i915/gem: Execbuffer objects must have struct pages.

[Nirmoy Das]

On 3/12/2024 3:55 PM, Jonathan Cavitt wrote:

We cannot write requests to objects without struct pages, so escape
early if the requests are bound to objects that lack them.

Signed-off-by: Jonathan Cavitt 
---

v2: s/vma-obj/vma->obj

  drivers/gpu/drm/i915/gem/i915_gem_execbuffer.c | 7 +++
  1 file changed, 7 insertions(+)

diff --git a/drivers/gpu/drm/i915/gem/i915_gem_execbuffer.c 
b/drivers/gpu/drm/i915/gem/i915_gem_execbuffer.c
index d3a771afb083e..adb4f9e78cb49 100644
--- a/drivers/gpu/drm/i915/gem/i915_gem_execbuffer.c
+++ b/drivers/gpu/drm/i915/gem/i915_gem_execbuffer.c
@@ -3313,6 +3313,13 @@ eb_requests_create(struct i915_execbuffer *eb, struct 
dma_fence *in_fence,
unsigned int i;
  
  	for_each_batch_create_order(eb, i) {

+   /* Do not write requests to objects without struct pages. */
+   if (eb->batches[i]->vma &&
+   !i915_gem_object_has_struct_page(eb->batches[i]->vma->obj)) 
{


As far as I understand, motivation of this patch is to avoid doing 
execbuf on dmabuf imported BO which are in error state of something. 
i915_gem_object_has_struct_page()  checks "obj->mem_flags & 
I915_BO_FLAG_STRUCT_PAGE" which is very i915 specific.


So I think this will not work and will cause regression in existing 
program which are trying to do the same with valid BO. Unfortunately I 
don't have any idea how to better detect that at this moment.



Regards,

Nirmoy


+   out_fence = ERR_PTR(-EINVAL);
+   return out_fence;
+   }
+
/* Allocate a request for this batch buffer nice and early. */
eb->requests[i] = i915_request_create(eb_find_context(eb, i));
if (IS_ERR(eb->requests[i])) {

Re: [PATCH v2] drm/i915/gem: Execbuffer objects must have struct pages.

[Andi Shyti]

Hi Jonathan,

On Tue, Mar 12, 2024 at 07:55:06AM -0700, Jonathan Cavitt wrote:
> We cannot write requests to objects without struct pages, so escape
> early if the requests are bound to objects that lack them.
> 
> Signed-off-by: Jonathan Cavitt 

is this a fix? Do you need

Fixes: 544460c33821 ("drm/i915: Multi-BB execbuf")
Cc: Matthew Brost 
Cc:  # v5.16+

?

Andi

> ---
> 
> v2: s/vma-obj/vma->obj
> 
>  drivers/gpu/drm/i915/gem/i915_gem_execbuffer.c | 7 +++
>  1 file changed, 7 insertions(+)
> 
> diff --git a/drivers/gpu/drm/i915/gem/i915_gem_execbuffer.c 
> b/drivers/gpu/drm/i915/gem/i915_gem_execbuffer.c
> index d3a771afb083e..adb4f9e78cb49 100644
> --- a/drivers/gpu/drm/i915/gem/i915_gem_execbuffer.c
> +++ b/drivers/gpu/drm/i915/gem/i915_gem_execbuffer.c
> @@ -3313,6 +3313,13 @@ eb_requests_create(struct i915_execbuffer *eb, struct 
> dma_fence *in_fence,
>   unsigned int i;
>  
>   for_each_batch_create_order(eb, i) {
> + /* Do not write requests to objects without struct pages. */
> + if (eb->batches[i]->vma &&
> + !i915_gem_object_has_struct_page(eb->batches[i]->vma->obj)) 
> {
> + out_fence = ERR_PTR(-EINVAL);
> + return out_fence;
> + }
> +
>   /* Allocate a request for this batch buffer nice and early. */
>   eb->requests[i] = i915_request_create(eb_find_context(eb, i));
>   if (IS_ERR(eb->requests[i])) {
> -- 
> 2.25.1

[PATCH v2] drm/i915/gem: Execbuffer objects must have struct pages.

[Jonathan Cavitt]

We cannot write requests to objects without struct pages, so escape
early if the requests are bound to objects that lack them.

Signed-off-by: Jonathan Cavitt 
---

v2: s/vma-obj/vma->obj

 drivers/gpu/drm/i915/gem/i915_gem_execbuffer.c | 7 +++
 1 file changed, 7 insertions(+)

diff --git a/drivers/gpu/drm/i915/gem/i915_gem_execbuffer.c 
b/drivers/gpu/drm/i915/gem/i915_gem_execbuffer.c
index d3a771afb083e..adb4f9e78cb49 100644
--- a/drivers/gpu/drm/i915/gem/i915_gem_execbuffer.c
+++ b/drivers/gpu/drm/i915/gem/i915_gem_execbuffer.c
@@ -3313,6 +3313,13 @@ eb_requests_create(struct i915_execbuffer *eb, struct 
dma_fence *in_fence,
unsigned int i;
 
for_each_batch_create_order(eb, i) {
+   /* Do not write requests to objects without struct pages. */
+   if (eb->batches[i]->vma &&
+   !i915_gem_object_has_struct_page(eb->batches[i]->vma->obj)) 
{
+   out_fence = ERR_PTR(-EINVAL);
+   return out_fence;
+   }
+
/* Allocate a request for this batch buffer nice and early. */
eb->requests[i] = i915_request_create(eb_find_context(eb, i));
if (IS_ERR(eb->requests[i])) {
-- 
2.25.1