Commit 4761791c authored by Shuicheng Lin's avatar Shuicheng Lin Committed by Matthew Brost
Browse files

drm/xe: Skip address copy for sync-only execs 



For parallel exec queues, xe_exec_ioctl() copied the batch buffer address
array from userspace without checking num_batch_buffer.
If user creates a sync-only exec that doesn't use the address field, the
exec will fail with -EFAULT.
Add num_batch_buffer check to skip the copy, and the exec could be executed
successfully.

Here is the sync-only exec:
struct drm_xe_exec exec = {
    .extensions = 0,
    .exec_queue_id = qid,
    .num_syncs = 1,
    .syncs = (uintptr_t)&sync,
    .address = 0,            /* ignored for sync-only */
    .num_batch_buffer = 0,   /* sync-only */
};

Fixes: dd08ebf6 ("drm/xe: Introduce a new DRM driver for Intel GPUs")
Cc: Matthew Brost <matthew.brost@intel.com>
Signed-off-by: default avatarShuicheng Lin <shuicheng.lin@intel.com>
Reviewed-by: default avatarMatthew Brost <matthew.brost@intel.com>
Signed-off-by: default avatarMatthew Brost <matthew.brost@intel.com>
Link: https://patch.msgid.link/20260122214053.3189366-2-shuicheng.lin@intel.com
parent 6ef02656

drivers/gpu/drm/xe/xe_exec.c

+3 −3
Original line number Diff line number Diff line
@@ -192,9 +192,9 @@ int xe_exec_ioctl(struct drm_device *dev, void *data, struct drm_file *file) 
		goto err_syncs;

	}



	if (xe_exec_queue_is_parallel(q)) {

		err = copy_from_user(addresses, addresses_user, sizeof(u64) *

				     q->width);

	if (args->num_batch_buffer && xe_exec_queue_is_parallel(q)) {

		err = copy_from_user(addresses, addresses_user,

				     sizeof(u64) * q->width);

		if (err) {

			err = -EFAULT;

			goto err_syncs;