Re: [PATCH v2] HID: intel-ish-hid: ignore post-init ENUM_DEVICES from firmware

[srinivas pandruvada <srinivas.pandruvada@linux.intel.com>]

On Mon, 2026-07-20 at 23:26 +0530, Wahid7852 wrote:
> From: Wahid Khan <wahidzk0091@gmail.com>
> 
> Some ISH firmware versions (observed on Tiger Lake LP, 8086:a0fc,
> GUID {33AECD58-B679-4E54-9BD9-A04D34F0C226}) periodically re-send an
> unsolicited HOSTIF_DM_ENUM_DEVICES response roughly every 79 seconds.
> 
> The current guard collapses two distinct cases into one condition:
> 
>   if (!(response_flag) || init_done)  ->  bad packet + ish_hw_reset
> 
> This incorrectly treats a valid post-init firmware announcement as a
> corrupted packet, triggering an ISH soft-reset and a full ISHTP
> re-initialisation cycle on each occurrence (~1100 times per day on
> affected hardware).
> 
> Split the check: reject messages with no response flag as before, but
> simply discard valid ENUM_DEVICES messages that arrive after init is
> complete.
> 
> Signed-off-by: Wahid Khan <wahidzk0091@gmail.com>

    Acked-by: Srinivas Pandruvada <srinivas.pandruvada@linux.intel.com>


Lixu, please add your tested by. I think you already tested this.

Thanks,
Srinivas

> ---
> v2: added proper sign off
> 
>  drivers/hid/intel-ish-hid/ishtp-hid-client.c | 5 +++--
>  1 file changed, 3 insertions(+), 2 deletions(-)
> 
> diff --git a/drivers/hid/intel-ish-hid/ishtp-hid-client.c
> b/drivers/hid/intel-ish-hid/ishtp-hid-client.c
> index 6d64008f2..ec5e8afe7 100644
> --- a/drivers/hid/intel-ish-hid/ishtp-hid-client.c
> +++ b/drivers/hid/intel-ish-hid/ishtp-hid-client.c
> @@ -113,8 +113,7 @@ static void process_recv(struct ishtp_cl
> *hid_ishtp_cl, void *recv_buf,
> 
>  		switch (recv_msg->hdr.command & CMD_MASK) {
>  		case HOSTIF_DM_ENUM_DEVICES:
> -			if ((!(recv_msg->hdr.command & ~CMD_MASK) ||
> -					client_data->init_done)) {
> +			if (!(recv_msg->hdr.command & ~CMD_MASK)) {
>  				++client_data->bad_recv_cnt;
>  				report_bad_packet(hid_ishtp_cl,
> recv_msg,
>  						  cur_pos,
> @@ -122,6 +121,8 @@ static void process_recv(struct ishtp_cl
> *hid_ishtp_cl, void *recv_buf,
>  				ish_hw_reset(ishtp_get_ishtp_device(
> hid_ishtp_cl));
>  				break;
>  			}
> +			if (client_data->init_done)
> +				break;
>  			client_data->hid_dev_count = (unsigned
> int)*payload;
>  			if (!client_data->hid_devices)
>  				client_data->hid_devices =
> devm_kcalloc(
> --
> 2.54.0