On Mon, Oct 20, 2025 at 09:02:43PM +0100, Akash Goel wrote:
> This commit addresses a memleak issue of panthor_vma (or drm_gpuva)
> structure in Panthor driver, that can happen if the GPU page table
> update operation to map the pages fail.
> The issue is very unlikely to occur in practice.
>
> v2: Add panthor_vm_op_ctx_return_vma() helper (Boris)
>
> Fixes: 647810ec2476 ("drm/panthor: Add the MMU/VM logical block")
> Signed-off-by: Akash Goel <[email protected]>
Reviewed-by: Liviu Dudau <[email protected]>
Best regards,
Liviu
> ---
> drivers/gpu/drm/panthor/panthor_mmu.c | 16 +++++++++++++++-
> 1 file changed, 15 insertions(+), 1 deletion(-)
>
> diff --git a/drivers/gpu/drm/panthor/panthor_mmu.c
> b/drivers/gpu/drm/panthor/panthor_mmu.c
> index 6dec4354e378..63af8ee89b08 100644
> --- a/drivers/gpu/drm/panthor/panthor_mmu.c
> +++ b/drivers/gpu/drm/panthor/panthor_mmu.c
> @@ -1146,6 +1146,18 @@ static void panthor_vm_cleanup_op_ctx(struct
> panthor_vm_op_ctx *op_ctx,
> }
> }
>
> +static void
> +panthor_vm_op_ctx_return_vma(struct panthor_vm_op_ctx *op_ctx,
> + struct panthor_vma *vma)
> +{
> + for (u32 i = 0; i < ARRAY_SIZE(op_ctx->preallocated_vmas); i++) {
> + if (!op_ctx->preallocated_vmas[i]) {
> + op_ctx->preallocated_vmas[i] = vma;
> + return;
> + }
> + }
> +}
> +
> static struct panthor_vma *
> panthor_vm_op_ctx_get_vma(struct panthor_vm_op_ctx *op_ctx)
> {
> @@ -2081,8 +2093,10 @@ static int panthor_gpuva_sm_step_map(struct
> drm_gpuva_op *op, void *priv)
> ret = panthor_vm_map_pages(vm, op->map.va.addr,
> flags_to_prot(vma->flags),
> op_ctx->map.sgt, op->map.gem.offset,
> op->map.va.range);
> - if (ret)
> + if (ret) {
> + panthor_vm_op_ctx_return_vma(op_ctx, vma);
> return ret;
> + }
>
> /* Ref owned by the mapping now, clear the obj field so we don't
> release the
> * pinning/obj ref behind GPUVA's back.
> --
> 2.25.1
>
--
====================
| I would like to |
| fix the world, |
| but they're not |
| giving me the |
\ source code! /
---------------
¯\_(ツ)_/¯
