[PATCH] drm/xe: Assign ioctl xe file handler to vm in xe_vm_create

[Matthew Auld]

On 08/08/2025 15:44, Piórkowski, Piotr wrote:
> From: Piotr Piórkowski <piotr.piorkowski at intel.com>
> 
> In several code paths, such as xe_pt_create(), the vm->xef field is used
> to determine whether a VM originates from userspace or the kernel.
> 
> Previously, this handler was only assigned in xe_vm_create_ioctl(),
> after the VM was created by xe_vm_create(). However, xe_vm_create()
> triggers page table creation, and that function assumes vm->xef should
> be already set. This could lead to incorrect origin detection.
> 
> To fix this problem and ensure consistency in the initialization of
> the VM object, let's move the assignment of this handler to
> xe_vm_create.
> 
> Fixes: 7f387e6012b6 ("drm/xe: add XE_BO_FLAG_PINNED_LATE_RESTORE")
> Signed-off-by: Piotr Piórkowski <piotr.piorkowski at intel.com>
> Cc: Matthew Auld <matthew.auld at intel.com>
> ---
>   drivers/gpu/drm/xe/xe_migrate.c    | 2 +-
>   drivers/gpu/drm/xe/xe_pxp_submit.c | 2 +-
>   drivers/gpu/drm/xe/xe_vm.c         | 8 +++-----
>   drivers/gpu/drm/xe/xe_vm.h         | 2 +-
>   4 files changed, 6 insertions(+), 8 deletions(-)
> 
> diff --git a/drivers/gpu/drm/xe/xe_migrate.c b/drivers/gpu/drm/xe/xe_migrate.c
> index 4effe10d815b..990403ee3752 100644
> --- a/drivers/gpu/drm/xe/xe_migrate.c
> +++ b/drivers/gpu/drm/xe/xe_migrate.c
> @@ -411,7 +411,7 @@ int xe_migrate_init(struct xe_migrate *m)
>   
>   	/* Special layout, prepared below.. */
>   	vm = xe_vm_create(xe, XE_VM_FLAG_MIGRATION |
> -			  XE_VM_FLAG_SET_TILE_ID(tile));
> +			  XE_VM_FLAG_SET_TILE_ID(tile), NULL);
>   	if (IS_ERR(vm))
>   		return PTR_ERR(vm);
>   
> diff --git a/drivers/gpu/drm/xe/xe_pxp_submit.c b/drivers/gpu/drm/xe/xe_pxp_submit.c
> index d92ec0f515b0..ca95f2a4d4ef 100644
> --- a/drivers/gpu/drm/xe/xe_pxp_submit.c
> +++ b/drivers/gpu/drm/xe/xe_pxp_submit.c
> @@ -101,7 +101,7 @@ static int allocate_gsc_client_resources(struct xe_gt *gt,
>   	xe_assert(xe, hwe);
>   
>   	/* PXP instructions must be issued from PPGTT */
> -	vm = xe_vm_create(xe, XE_VM_FLAG_GSC);
> +	vm = xe_vm_create(xe, XE_VM_FLAG_GSC, NULL);
>   	if (IS_ERR(vm))
>   		return PTR_ERR(vm);
>   
> diff --git a/drivers/gpu/drm/xe/xe_vm.c b/drivers/gpu/drm/xe/xe_vm.c
> index 432ea325677d..26948eb6e283 100644
> --- a/drivers/gpu/drm/xe/xe_vm.c
> +++ b/drivers/gpu/drm/xe/xe_vm.c
> @@ -1640,7 +1640,7 @@ static void xe_vm_free_scratch(struct xe_vm *vm)
>   	}
>   }
>   
> -struct xe_vm *xe_vm_create(struct xe_device *xe, u32 flags)
> +struct xe_vm *xe_vm_create(struct xe_device *xe, u32 flags, struct xe_file *xef)
>   {
>   	struct drm_gem_object *vm_resv_obj;
>   	struct xe_vm *vm;
> @@ -1660,8 +1660,8 @@ struct xe_vm *xe_vm_create(struct xe_device *xe, u32 flags)
>   
>   	vm->xe = xe;
>   
> +	vm->xef = xe_file_get(xef);

I think some of the error paths in here also need adjusting to have the 
put(), like with err_no_resv etc. Othewise I think looks OK.

I guess optional, but we could now potentially also move usm.asid and 
the pt tracking thing, and make that conditional on xef.

>   	vm->size = 1ull << xe->info.va_bits;
> -
>   	vm->flags = flags;
>   
>   	/**
> @@ -2097,7 +2097,7 @@ int xe_vm_create_ioctl(struct drm_device *dev, void *data,
>   	if (args->flags & DRM_XE_VM_CREATE_FLAG_FAULT_MODE)
>   		flags |= XE_VM_FLAG_FAULT_MODE;
>   
> -	vm = xe_vm_create(xe, flags);
> +	vm = xe_vm_create(xe, flags, xef);
>   	if (IS_ERR(vm))
>   		return PTR_ERR(vm);
>   
> @@ -2113,8 +2113,6 @@ int xe_vm_create_ioctl(struct drm_device *dev, void *data,
>   		vm->usm.asid = asid;
>   	}
>   
> -	vm->xef = xe_file_get(xef);
> -
>   	/* Record BO memory for VM pagetable created against client */
>   	for_each_tile(tile, xe, id)
>   		if (vm->pt_root[id])
> diff --git a/drivers/gpu/drm/xe/xe_vm.h b/drivers/gpu/drm/xe/xe_vm.h
> index 3475a118f666..2f213737c7e5 100644
> --- a/drivers/gpu/drm/xe/xe_vm.h
> +++ b/drivers/gpu/drm/xe/xe_vm.h
> @@ -26,7 +26,7 @@ struct xe_sync_entry;
>   struct xe_svm_range;
>   struct drm_exec;
>   
> -struct xe_vm *xe_vm_create(struct xe_device *xe, u32 flags);
> +struct xe_vm *xe_vm_create(struct xe_device *xe, u32 flags, struct xe_file *xef);
>   
>   struct xe_vm *xe_vm_lookup(struct xe_file *xef, u32 id);
>   int xe_vma_cmp_vma_cb(const void *key, const struct rb_node *node);