Re: [PATCH V1 19/20] accel/amdxdna: Add stub hwctx_config for AIE4

[sashiko-bot@kernel.org]

Thank you for your contribution! Sashiko AI review found 1 potential issue(s) to consider:
- [Medium] amdxdna: aie4_hwctx_config unconditionally returns success for unsupported types
--

commit 2fb62e44c1bbca14b0a25248c16851b8cb0c7aa6
Author: David Zhang <yidong.zhang@amd.com>

accel/amdxdna: Add stub hwctx_config for AIE4

XRT issues DRM_AMDXDNA_CONFIG_HWCTX during hardware context
initialization. If hwctx_config is NULL, the ioctl returns -EOPNOTSUPP,
causing userspace validation tests like GEMM to fail. Add a stub 
aie4_hwctx_config() returning 0 and wire it to aie4_vf_ops and
aie4_classic_ops.

> diff --git a/drivers/accel/amdxdna/aie4_pci.c b/drivers/accel/amdxdna/aie4_pci.c
> index 007b14be5245f..62ee7dfc7bd37 100644
> --- a/drivers/accel/amdxdna/aie4_pci.c
> +++ b/drivers/accel/amdxdna/aie4_pci.c
> @@ -1369,12 +1369,19 @@ const struct amdxdna_dev_ops aie4_pf_ops = {
>  	.runtime_suspend	= aie4_pf_runtime_suspend,
>  };
>  
> +static int aie4_hwctx_config(struct amdxdna_hwctx *hwctx, u32 type, u64 value,
> +			     void *buf, u32 size)
> +{
> +	return 0;
> +}

[Severity: Medium]
Does returning 0 unconditionally here falsely report success for unsupported
hardware context configuration commands?

If a userspace library like XRT calls the AMDXDNA_CONFIG_HWCTX ioctl with an
unsupported type (such as DRM_AMDXDNA_HWCTX_ASSIGN_DBG_BUF), returning 0
could cause userspace to assume the operation was successful. Could this
cause userspace to read uninitialized or garbage data from the buffer since
it relies on standard kernel error codes like -EOPNOTSUPP or -EINVAL to
detect hardware capabilities?

> +
>  const struct amdxdna_dev_ops aie4_vf_ops = {
>  	.init			= aie4_vf_init,
>  	.fini			= aie4_vf_fini,
>  	.debugfs_init		= aie4_debugfs_init,
>  	.hwctx_init		= aie4_hwctx_init,
>  	.hwctx_fini		= aie4_hwctx_fini,
> +	.hwctx_config		= aie4_hwctx_config,
>  	.cmd_submit		= aie4_cmd_submit,
>  	.cmd_wait		= aie4_cmd_wait,
>  	.get_aie_info		= aie4_get_info,

-- 
Sashiko AI review · https://sashiko.dev/#/patchset/20260930033233.1727265-1-yidong.zhang@amd.com?part=19