Re: [PATCH] net: qrtr: resend HELLO on MHI resume

[Jeff Johnson]

On 9/15/2026 3:48 AM, Vlastimil Babka wrote:
> On 9/11/26 12:44, Manivannan Sadhasivam wrote:
>> On Wed, Sep 09, 2026 at 01:58:44PM +0800, Daniel J Blueman wrote:
>>> Since the MHI HELLO exchange was relocated, it is sent only at device
>>> registration. During a suspend-resume cycle, the firmware in WiFi
>>> cards such as WCN7850 indefinitely waits for another HELLO,
>>> triggering:
>>>
>>>   ath12k_wifi7_pci 0004:01:00.0: timeout while waiting for restart complete
>>>   ath12k_wifi7_pci 0004:01:00.0: failed to resume core: -110
>>>
>>> Fix this by triggering the handshake from resume_early in the MHI
>>> transport.
>>>
>>> Validated on Qualcomm X1E-801800 on Lenovo Slim 7x across 10
>>> suspend-resume cycles.
>>>
>>> Fixes: 544d85de4dc2 ("net: qrtr: Send HELLO message on endpoint register")
>>> Signed-off-by: Daniel J Blueman <daniel@xxxxxxxxx>
>>> ---
>>>  net/qrtr/af_qrtr.c | 13 +++++++++++++
>>>  net/qrtr/mhi.c     | 10 +++++++++-
>>>  net/qrtr/qrtr.h    |  2 ++
>>>  3 files changed, 24 insertions(+), 1 deletion(-)
>>>
>>> diff --git a/net/qrtr/af_qrtr.c b/net/qrtr/af_qrtr.c
>>> index 78347c937af7..2ffcfc2fdb4a 100644
>>> --- a/net/qrtr/af_qrtr.c
>>> +++ b/net/qrtr/af_qrtr.c
>>> @@ -623,6 +623,19 @@ static void qrtr_hello_work(struct work_struct *work)
>>>  	qrtr_port_put(ctrl);
>>>  }
>>>  
>>> +/* Trigger the HELLO handshake after the remote has been reset, eg on resume */
>>
>> Use proper kernel-doc please.
> 
> Please prioritize merging this sooner than later (it's a regression from
> 7.3-rc2 that would hit people if it made it to 7.3 final) even if it means
> fixing up non-critical aspects later, or by maintainer upon merging.

Concur. I recently fast-forwarded my ath tree and picked up the buggy commit,
so everyone using my tree is now affected.

And just want to point out that many of the function comments in this file do
not use kernel-doc format, so I would not consider that a blocker. But it also
would be trivial for the maintainer to add.

I've tested this on my HP ZBook 14 where I've replaced the OEM Wi-Fi adapter
with WCN7850...

Tested-by: Jeff Johnson <jeff.johnson@xxxxxxxxxxxxxxxx>

/jeff